Staging: mei: move the mei code out of staging

It's been cleaned up, and there's nothing else left to do, so move it
out of staging into drivers/misc/ where all can use it now.

Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Oren Weil <oren.jer.weil@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/Kconfig

@@ -0,0 +1,28 @@
+config INTEL_MEI
+	tristate "Intel Management Engine Interface (Intel MEI)"
+	depends on X86 && PCI && EXPERIMENTAL && WATCHDOG_CORE
+	help
+	  The Intel Management Engine (Intel ME) provides Manageability,
+	  Security and Media services for system containing Intel chipsets.
+	  if selected /dev/mei misc device will be created.
+
+	  Supported Chipsets are:
+	  7 Series Chipset Family
+	  6 Series Chipset Family
+	  5 Series Chipset Family
+	  4 Series Chipset Family
+	  Mobile 4 Series Chipset Family
+	  ICH9
+	  82946GZ/GL
+	  82G35 Express
+	  82Q963/Q965
+	  82P965/G965
+	  Mobile PM965/GM965
+	  Mobile GME965/GLE960
+	  82Q35 Express
+	  82G33/G31/P35/P31 Express
+	  82Q33 Express
+	  82X38/X48 Express
+
+	  For more information see
+	  <http://software.intel.com/en-us/manageability/>

drivers/misc/mei/Makefile

@@ -0,0 +1,11 @@
+#
+# Makefile - Intel Management Engine Interface (Intel MEI) Linux driver
+# Copyright (c) 2010-2011, Intel Corporation.
+#
+obj-$(CONFIG_INTEL_MEI) += mei.o
+mei-objs := init.o
+mei-objs += interrupt.o
+mei-objs += interface.o
+mei-objs += iorw.o
+mei-objs += main.o
+mei-objs += wd.o

drivers/misc/mei/TODO

@@ -0,0 +1,10 @@
+TODO:
+	- Cleanup and split the timer function
+Upon Unstaging:
+	- move mei.h to include/linux/mei.h
+	- Documentation/ioctl/ioctl-number.txt
+	- move mei.txt under Documentation/mei/
+	- move mei-amt-version.c under Documentation/mei
+	- add hostprogs-y for mei-amt-version.c
+	- drop mei_version.h
+	- Updated MAINTAINERS

drivers/misc/mei/hw.h

@@ -0,0 +1,332 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#ifndef _MEI_HW_TYPES_H_
+#define _MEI_HW_TYPES_H_
+
+#include <linux/uuid.h>
+
+/*
+ * Timeouts
+ */
+#define MEI_INTEROP_TIMEOUT    (HZ * 7)
+#define MEI_CONNECT_TIMEOUT		3	/* at least 2 seconds */
+
+#define CONNECT_TIMEOUT        15	/* HPS definition */
+#define INIT_CLIENTS_TIMEOUT   15	/* HPS definition */
+
+#define IAMTHIF_STALL_TIMER		12	/* seconds */
+#define IAMTHIF_READ_TIMER		10000	/* ms */
+
+/*
+ * Internal Clients Number
+ */
+#define MEI_WD_HOST_CLIENT_ID          1
+#define MEI_IAMTHIF_HOST_CLIENT_ID     2
+
+/*
+ * MEI device IDs
+ */
+#define    MEI_DEV_ID_82946GZ	0x2974  /* 82946GZ/GL */
+#define    MEI_DEV_ID_82G35	0x2984  /* 82G35 Express */
+#define    MEI_DEV_ID_82Q965	0x2994  /* 82Q963/Q965 */
+#define    MEI_DEV_ID_82G965	0x29A4  /* 82P965/G965 */
+
+#define    MEI_DEV_ID_82GM965	0x2A04  /* Mobile PM965/GM965 */
+#define    MEI_DEV_ID_82GME965	0x2A14  /* Mobile GME965/GLE960 */
+
+#define    MEI_DEV_ID_ICH9_82Q35 0x29B4  /* 82Q35 Express */
+#define    MEI_DEV_ID_ICH9_82G33 0x29C4  /* 82G33/G31/P35/P31 Express */
+#define    MEI_DEV_ID_ICH9_82Q33 0x29D4  /* 82Q33 Express */
+#define    MEI_DEV_ID_ICH9_82X38 0x29E4  /* 82X38/X48 Express */
+#define    MEI_DEV_ID_ICH9_3200  0x29F4  /* 3200/3210 Server */
+
+#define    MEI_DEV_ID_ICH9_6	0x28B4  /* Bearlake */
+#define    MEI_DEV_ID_ICH9_7	0x28C4  /* Bearlake */
+#define    MEI_DEV_ID_ICH9_8	0x28D4  /* Bearlake */
+#define    MEI_DEV_ID_ICH9_9    0x28E4  /* Bearlake */
+#define    MEI_DEV_ID_ICH9_10	0x28F4  /* Bearlake */
+
+#define    MEI_DEV_ID_ICH9M_1	0x2A44  /* Cantiga */
+#define    MEI_DEV_ID_ICH9M_2	0x2A54  /* Cantiga */
+#define    MEI_DEV_ID_ICH9M_3	0x2A64  /* Cantiga */
+#define    MEI_DEV_ID_ICH9M_4	0x2A74  /* Cantiga */
+
+#define    MEI_DEV_ID_ICH10_1	0x2E04  /* Eaglelake */
+#define    MEI_DEV_ID_ICH10_2	0x2E14  /* Eaglelake */
+#define    MEI_DEV_ID_ICH10_3	0x2E24  /* Eaglelake */
+#define    MEI_DEV_ID_ICH10_4	0x2E34  /* Eaglelake */
+
+#define    MEI_DEV_ID_IBXPK_1	0x3B64  /* Calpella */
+#define    MEI_DEV_ID_IBXPK_2	0x3B65  /* Calpella */
+
+#define    MEI_DEV_ID_CPT_1	0x1C3A    /* Cougerpoint */
+#define    MEI_DEV_ID_PBG_1	0x1D3A    /* PBG */
+
+#define    MEI_DEV_ID_PPT_1	0x1E3A    /* Pantherpoint PPT */
+#define    MEI_DEV_ID_PPT_2	0x1CBA    /* Pantherpoint PPT */
+#define    MEI_DEV_ID_PPT_3	0x1DBA    /* Pantherpoint PPT */
+
+
+/*
+ * MEI HW Section
+ */
+
+/* MEI registers */
+/* H_CB_WW - Host Circular Buffer (CB) Write Window register */
+#define H_CB_WW    0
+/* H_CSR - Host Control Status register */
+#define H_CSR      4
+/* ME_CB_RW - ME Circular Buffer Read Window register (read only) */
+#define ME_CB_RW   8
+/* ME_CSR_HA - ME Control Status Host Access register (read only) */
+#define ME_CSR_HA  0xC
+
+
+/* register bits of H_CSR (Host Control Status register) */
+/* Host Circular Buffer Depth - maximum number of 32-bit entries in CB */
+#define H_CBD             0xFF000000
+/* Host Circular Buffer Write Pointer */
+#define H_CBWP            0x00FF0000
+/* Host Circular Buffer Read Pointer */
+#define H_CBRP            0x0000FF00
+/* Host Reset */
+#define H_RST             0x00000010
+/* Host Ready */
+#define H_RDY             0x00000008
+/* Host Interrupt Generate */
+#define H_IG              0x00000004
+/* Host Interrupt Status */
+#define H_IS              0x00000002
+/* Host Interrupt Enable */
+#define H_IE              0x00000001
+
+
+/* register bits of ME_CSR_HA (ME Control Status Host Access register) */
+/* ME CB (Circular Buffer) Depth HRA (Host Read Access) - host read only
+access to ME_CBD */
+#define ME_CBD_HRA        0xFF000000
+/* ME CB Write Pointer HRA - host read only access to ME_CBWP */
+#define ME_CBWP_HRA       0x00FF0000
+/* ME CB Read Pointer HRA - host read only access to ME_CBRP */
+#define ME_CBRP_HRA       0x0000FF00
+/* ME Reset HRA - host read only access to ME_RST */
+#define ME_RST_HRA        0x00000010
+/* ME Ready HRA - host read only access to ME_RDY */
+#define ME_RDY_HRA        0x00000008
+/* ME Interrupt Generate HRA - host read only access to ME_IG */
+#define ME_IG_HRA         0x00000004
+/* ME Interrupt Status HRA - host read only access to ME_IS */
+#define ME_IS_HRA         0x00000002
+/* ME Interrupt Enable HRA - host read only access to ME_IE */
+#define ME_IE_HRA         0x00000001
+
+/*
+ * MEI Version
+ */
+#define HBM_MINOR_VERSION                   0
+#define HBM_MAJOR_VERSION                   1
+#define HBM_TIMEOUT                         1	/* 1 second */
+
+/* Host bus message command opcode */
+#define MEI_HBM_CMD_OP_MSK                  0x7f
+/* Host bus message command RESPONSE */
+#define MEI_HBM_CMD_RES_MSK                 0x80
+
+/*
+ * MEI Bus Message Command IDs
+ */
+#define HOST_START_REQ_CMD                  0x01
+#define HOST_START_RES_CMD                  0x81
+
+#define HOST_STOP_REQ_CMD                   0x02
+#define HOST_STOP_RES_CMD                   0x82
+
+#define ME_STOP_REQ_CMD                     0x03
+
+#define HOST_ENUM_REQ_CMD                   0x04
+#define HOST_ENUM_RES_CMD                   0x84
+
+#define HOST_CLIENT_PROPERTIES_REQ_CMD      0x05
+#define HOST_CLIENT_PROPERTIES_RES_CMD      0x85
+
+#define CLIENT_CONNECT_REQ_CMD              0x06
+#define CLIENT_CONNECT_RES_CMD              0x86
+
+#define CLIENT_DISCONNECT_REQ_CMD           0x07
+#define CLIENT_DISCONNECT_RES_CMD           0x87
+
+#define MEI_FLOW_CONTROL_CMD                0x08
+
+/*
+ * MEI Stop Reason
+ * used by hbm_host_stop_request.reason
+ */
+enum mei_stop_reason_types {
+	DRIVER_STOP_REQUEST = 0x00,
+	DEVICE_D1_ENTRY = 0x01,
+	DEVICE_D2_ENTRY = 0x02,
+	DEVICE_D3_ENTRY = 0x03,
+	SYSTEM_S1_ENTRY = 0x04,
+	SYSTEM_S2_ENTRY = 0x05,
+	SYSTEM_S3_ENTRY = 0x06,
+	SYSTEM_S4_ENTRY = 0x07,
+	SYSTEM_S5_ENTRY = 0x08
+};
+
+/*
+ * Client Connect Status
+ * used by hbm_client_connect_response.status
+ */
+enum client_connect_status_types {
+	CCS_SUCCESS = 0x00,
+	CCS_NOT_FOUND = 0x01,
+	CCS_ALREADY_STARTED = 0x02,
+	CCS_OUT_OF_RESOURCES = 0x03,
+	CCS_MESSAGE_SMALL = 0x04
+};
+
+/*
+ * Client Disconnect Status
+ */
+enum client_disconnect_status_types {
+	CDS_SUCCESS = 0x00
+};
+
+/*
+ *  MEI BUS Interface Section
+ */
+struct mei_msg_hdr {
+	u32 me_addr:8;
+	u32 host_addr:8;
+	u32 length:9;
+	u32 reserved:6;
+	u32 msg_complete:1;
+} __packed;
+
+
+struct mei_bus_message {
+	u8 hbm_cmd;
+	u8 data[0];
+} __packed;
+
+struct hbm_version {
+	u8 minor_version;
+	u8 major_version;
+} __packed;
+
+struct hbm_host_version_request {
+	u8 hbm_cmd;
+	u8 reserved;
+	struct hbm_version host_version;
+} __packed;
+
+struct hbm_host_version_response {
+	u8 hbm_cmd;
+	u8 host_version_supported;
+	struct hbm_version me_max_version;
+} __packed;
+
+struct hbm_host_stop_request {
+	u8 hbm_cmd;
+	u8 reason;
+	u8 reserved[2];
+} __packed;
+
+struct hbm_host_stop_response {
+	u8 hbm_cmd;
+	u8 reserved[3];
+} __packed;
+
+struct hbm_me_stop_request {
+	u8 hbm_cmd;
+	u8 reason;
+	u8 reserved[2];
+} __packed;
+
+struct hbm_host_enum_request {
+	u8 hbm_cmd;
+	u8 reserved[3];
+} __packed;
+
+struct hbm_host_enum_response {
+	u8 hbm_cmd;
+	u8 reserved[3];
+	u8 valid_addresses[32];
+} __packed;
+
+struct mei_client_properties {
+	uuid_le protocol_name;
+	u8 protocol_version;
+	u8 max_number_of_connections;
+	u8 fixed_address;
+	u8 single_recv_buf;
+	u32 max_msg_length;
+} __packed;
+
+struct hbm_props_request {
+	u8 hbm_cmd;
+	u8 address;
+	u8 reserved[2];
+} __packed;
+
+
+struct hbm_props_response {
+	u8 hbm_cmd;
+	u8 address;
+	u8 status;
+	u8 reserved[1];
+	struct mei_client_properties client_properties;
+} __packed;
+
+struct hbm_client_connect_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved;
+} __packed;
+
+struct hbm_client_connect_response {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 status;
+} __packed;
+
+struct hbm_client_disconnect_request {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved[1];
+} __packed;
+
+#define MEI_FC_MESSAGE_RESERVED_LENGTH           5
+
+struct hbm_flow_control {
+	u8 hbm_cmd;
+	u8 me_addr;
+	u8 host_addr;
+	u8 reserved[MEI_FC_MESSAGE_RESERVED_LENGTH];
+} __packed;
+
+struct mei_me_client {
+	struct mei_client_properties props;
+	u8 client_id;
+	u8 mei_flow_ctrl_creds;
+} __packed;
+
+
+#endif

drivers/misc/mei/init.c

@@ -0,0 +1,735 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/delay.h>
+
+#include "mei_dev.h"
+#include "hw.h"
+#include "interface.h"
+#include "mei.h"
+
+const uuid_le mei_amthi_guid  = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d, 0xac,
+						0xa8, 0x46, 0xe0, 0xff, 0x65,
+						0x81, 0x4c);
+
+/**
+ * mei_io_list_init - Sets up a queue list.
+ *
+ * @list: An instance io list structure
+ * @dev: the device structure
+ */
+void mei_io_list_init(struct mei_io_list *list)
+{
+	/* initialize our queue list */
+	INIT_LIST_HEAD(&list->mei_cb.cb_list);
+}
+
+/**
+ * mei_io_list_flush - removes list entry belonging to cl.
+ *
+ * @list:  An instance of our list structure
+ * @cl: private data of the file object
+ */
+void mei_io_list_flush(struct mei_io_list *list, struct mei_cl *cl)
+{
+	struct mei_cl_cb *pos;
+	struct mei_cl_cb *next;
+
+	list_for_each_entry_safe(pos, next, &list->mei_cb.cb_list, cb_list) {
+		if (pos->file_private) {
+			struct mei_cl *cl_tmp;
+			cl_tmp = (struct mei_cl *)pos->file_private;
+			if (mei_cl_cmp_id(cl, cl_tmp))
+				list_del(&pos->cb_list);
+		}
+	}
+}
+/**
+ * mei_cl_flush_queues - flushes queue lists belonging to cl.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ */
+int mei_cl_flush_queues(struct mei_cl *cl)
+{
+	if (!cl || !cl->dev)
+		return -EINVAL;
+
+	dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
+	mei_io_list_flush(&cl->dev->read_list, cl);
+	mei_io_list_flush(&cl->dev->write_list, cl);
+	mei_io_list_flush(&cl->dev->write_waiting_list, cl);
+	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
+	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
+	mei_io_list_flush(&cl->dev->amthi_cmd_list, cl);
+	mei_io_list_flush(&cl->dev->amthi_read_complete_list, cl);
+	return 0;
+}
+
+
+
+/**
+ * mei_reset_iamthif_params - initializes mei device iamthif
+ *
+ * @dev: the device structure
+ */
+static void mei_reset_iamthif_params(struct mei_device *dev)
+{
+	/* reset iamthif parameters. */
+	dev->iamthif_current_cb = NULL;
+	dev->iamthif_msg_buf_size = 0;
+	dev->iamthif_msg_buf_index = 0;
+	dev->iamthif_canceled = false;
+	dev->iamthif_ioctl = false;
+	dev->iamthif_state = MEI_IAMTHIF_IDLE;
+	dev->iamthif_timer = 0;
+}
+
+/**
+ * init_mei_device - allocates and initializes the mei device structure
+ *
+ * @pdev: The pci device structure
+ *
+ * returns The mei_device_device pointer on success, NULL on failure.
+ */
+struct mei_device *mei_device_init(struct pci_dev *pdev)
+{
+	struct mei_device *dev;
+
+	dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	/* setup our list array */
+	INIT_LIST_HEAD(&dev->file_list);
+	INIT_LIST_HEAD(&dev->wd_cl.link);
+	INIT_LIST_HEAD(&dev->iamthif_cl.link);
+	mutex_init(&dev->device_lock);
+	init_waitqueue_head(&dev->wait_recvd_msg);
+	init_waitqueue_head(&dev->wait_stop_wd);
+	dev->mei_state = MEI_INITIALIZING;
+	dev->iamthif_state = MEI_IAMTHIF_IDLE;
+	dev->wd_interface_reg = false;
+
+
+	mei_io_list_init(&dev->read_list);
+	mei_io_list_init(&dev->write_list);
+	mei_io_list_init(&dev->write_waiting_list);
+	mei_io_list_init(&dev->ctrl_wr_list);
+	mei_io_list_init(&dev->ctrl_rd_list);
+	mei_io_list_init(&dev->amthi_cmd_list);
+	mei_io_list_init(&dev->amthi_read_complete_list);
+	dev->pdev = pdev;
+	return dev;
+}
+
+/**
+ * mei_hw_init - initializes host and fw to start work.
+ *
+ * @dev: the device structure
+ *
+ * returns 0 on success, <0 on failure.
+ */
+int mei_hw_init(struct mei_device *dev)
+{
+	int err = 0;
+	int ret;
+
+	mutex_lock(&dev->device_lock);
+
+	dev->host_hw_state = mei_hcsr_read(dev);
+	dev->me_hw_state = mei_mecsr_read(dev);
+	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
+	    dev->host_hw_state, dev->me_hw_state);
+
+	/* acknowledge interrupt and stop interupts */
+	if ((dev->host_hw_state & H_IS) == H_IS)
+		mei_reg_write(dev, H_CSR, dev->host_hw_state);
+
+	dev->recvd_msg = false;
+	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
+
+	mei_reset(dev, 1);
+
+	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
+	    dev->host_hw_state, dev->me_hw_state);
+
+	/* wait for ME to turn on ME_RDY */
+	if (!dev->recvd_msg) {
+		mutex_unlock(&dev->device_lock);
+		err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
+			dev->recvd_msg, MEI_INTEROP_TIMEOUT);
+		mutex_lock(&dev->device_lock);
+	}
+
+	if (err <= 0 && !dev->recvd_msg) {
+		dev->mei_state = MEI_DISABLED;
+		dev_dbg(&dev->pdev->dev,
+			"wait_event_interruptible_timeout failed"
+			"on wait for ME to turn on ME_RDY.\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
+	      ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
+		dev->mei_state = MEI_DISABLED;
+		dev_dbg(&dev->pdev->dev,
+			"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
+			dev->host_hw_state, dev->me_hw_state);
+
+		if (!(dev->host_hw_state & H_RDY))
+			dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
+
+		if (!(dev->me_hw_state & ME_RDY_HRA))
+			dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
+
+		dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (dev->version.major_version != HBM_MAJOR_VERSION ||
+	    dev->version.minor_version != HBM_MINOR_VERSION) {
+		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	dev->recvd_msg = false;
+	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
+	    dev->host_hw_state, dev->me_hw_state);
+	dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
+	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
+	dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
+	ret = 0;
+
+out:
+	mutex_unlock(&dev->device_lock);
+	return ret;
+}
+
+/**
+ * mei_hw_reset - resets fw via mei csr register.
+ *
+ * @dev: the device structure
+ * @interrupts_enabled: if interrupt should be enabled after reset.
+ */
+static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
+{
+	dev->host_hw_state |= (H_RST | H_IG);
+
+	if (interrupts_enabled)
+		mei_enable_interrupts(dev);
+	else
+		mei_disable_interrupts(dev);
+}
+
+/**
+ * mei_reset - resets host and fw.
+ *
+ * @dev: the device structure
+ * @interrupts_enabled: if interrupt should be enabled after reset.
+ */
+void mei_reset(struct mei_device *dev, int interrupts_enabled)
+{
+	struct mei_cl *cl_pos = NULL;
+	struct mei_cl *cl_next = NULL;
+	struct mei_cl_cb *cb_pos = NULL;
+	struct mei_cl_cb *cb_next = NULL;
+	bool unexpected;
+
+	if (dev->mei_state == MEI_RECOVERING_FROM_RESET) {
+		dev->need_reset = true;
+		return;
+	}
+
+	unexpected = (dev->mei_state != MEI_INITIALIZING &&
+			dev->mei_state != MEI_DISABLED &&
+			dev->mei_state != MEI_POWER_DOWN &&
+			dev->mei_state != MEI_POWER_UP);
+
+	dev->host_hw_state = mei_hcsr_read(dev);
+
+	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
+	    dev->host_hw_state);
+
+	mei_hw_reset(dev, interrupts_enabled);
+
+	dev->host_hw_state &= ~H_RST;
+	dev->host_hw_state |= H_IG;
+
+	mei_hcsr_set(dev);
+
+	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
+	    dev->host_hw_state);
+
+	dev->need_reset = false;
+
+	if (dev->mei_state != MEI_INITIALIZING) {
+		if (dev->mei_state != MEI_DISABLED &&
+		    dev->mei_state != MEI_POWER_DOWN)
+			dev->mei_state = MEI_RESETING;
+
+		list_for_each_entry_safe(cl_pos,
+				cl_next, &dev->file_list, link) {
+			cl_pos->state = MEI_FILE_DISCONNECTED;
+			cl_pos->mei_flow_ctrl_creds = 0;
+			cl_pos->read_cb = NULL;
+			cl_pos->timer_count = 0;
+		}
+		/* remove entry if already in list */
+		dev_dbg(&dev->pdev->dev, "list del iamthif and wd file list.\n");
+		mei_remove_client_from_file_list(dev,
+				dev->wd_cl.host_client_id);
+
+		mei_remove_client_from_file_list(dev,
+				dev->iamthif_cl.host_client_id);
+
+		mei_reset_iamthif_params(dev);
+		dev->wd_due_counter = 0;
+		dev->extra_write_index = 0;
+	}
+
+	dev->me_clients_num = 0;
+	dev->rd_msg_hdr = 0;
+	dev->stop = false;
+	dev->wd_pending = false;
+
+	/* update the state of the registers after reset */
+	dev->host_hw_state = mei_hcsr_read(dev);
+	dev->me_hw_state = mei_mecsr_read(dev);
+
+	dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
+	    dev->host_hw_state, dev->me_hw_state);
+
+	if (unexpected)
+		dev_warn(&dev->pdev->dev, "unexpected reset.\n");
+
+	/* Wake up all readings so they can be interrupted */
+	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
+		if (waitqueue_active(&cl_pos->rx_wait)) {
+			dev_dbg(&dev->pdev->dev, "Waking up client!\n");
+			wake_up_interruptible(&cl_pos->rx_wait);
+		}
+	}
+	/* remove all waiting requests */
+	list_for_each_entry_safe(cb_pos, cb_next,
+			&dev->write_list.mei_cb.cb_list, cb_list) {
+		list_del(&cb_pos->cb_list);
+		mei_free_cb_private(cb_pos);
+	}
+}
+
+
+
+/**
+ * host_start_message - mei host sends start message.
+ *
+ * @dev: the device structure
+ *
+ * returns none.
+ */
+void mei_host_start_message(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct hbm_host_version_request *host_start_req;
+
+	/* host start message */
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	mei_hdr->host_addr = 0;
+	mei_hdr->me_addr = 0;
+	mei_hdr->length = sizeof(struct hbm_host_version_request);
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	host_start_req =
+	    (struct hbm_host_version_request *) &dev->wr_msg_buf[1];
+	memset(host_start_req, 0, sizeof(struct hbm_host_version_request));
+	host_start_req->hbm_cmd = HOST_START_REQ_CMD;
+	host_start_req->host_version.major_version = HBM_MAJOR_VERSION;
+	host_start_req->host_version.minor_version = HBM_MINOR_VERSION;
+	dev->recvd_msg = false;
+	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_start_req,
+				       mei_hdr->length)) {
+		dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
+		dev->mei_state = MEI_RESETING;
+		mei_reset(dev, 1);
+	}
+	dev->init_clients_state = MEI_START_MESSAGE;
+	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
+	return ;
+}
+
+/**
+ * host_enum_clients_message - host sends enumeration client request message.
+ *
+ * @dev: the device structure
+ *
+ * returns none.
+ */
+void mei_host_enum_clients_message(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct hbm_host_enum_request *host_enum_req;
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	/* enumerate clients */
+	mei_hdr->host_addr = 0;
+	mei_hdr->me_addr = 0;
+	mei_hdr->length = sizeof(struct hbm_host_enum_request);
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	host_enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
+	memset(host_enum_req, 0, sizeof(struct hbm_host_enum_request));
+	host_enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
+	if (mei_write_message(dev, mei_hdr, (unsigned char *)host_enum_req,
+				mei_hdr->length)) {
+		dev->mei_state = MEI_RESETING;
+		dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
+		mei_reset(dev, 1);
+	}
+	dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
+	dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
+	return;
+}
+
+
+/**
+ * allocate_me_clients_storage - allocates storage for me clients
+ *
+ * @dev: the device structure
+ *
+ * returns none.
+ */
+void mei_allocate_me_clients_storage(struct mei_device *dev)
+{
+	struct mei_me_client *clients;
+	int b;
+
+	/* count how many ME clients we have */
+	for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
+		dev->me_clients_num++;
+
+	if (dev->me_clients_num <= 0)
+		return ;
+
+
+	if (dev->me_clients != NULL) {
+		kfree(dev->me_clients);
+		dev->me_clients = NULL;
+	}
+	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
+		dev->me_clients_num * sizeof(struct mei_me_client));
+	/* allocate storage for ME clients representation */
+	clients = kcalloc(dev->me_clients_num,
+			sizeof(struct mei_me_client), GFP_KERNEL);
+	if (!clients) {
+		dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
+		dev->mei_state = MEI_RESETING;
+		mei_reset(dev, 1);
+		return ;
+	}
+	dev->me_clients = clients;
+	return ;
+}
+/**
+ * host_client_properties - reads properties for client
+ *
+ * @dev: the device structure
+ *
+ * returns:
+ * 	< 0 - Error.
+ *  = 0 - no more clients.
+ *  = 1 - still have clients to send properties request.
+ */
+int mei_host_client_properties(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_header;
+	struct hbm_props_request *host_cli_req;
+	int b;
+	u8 client_num = dev->me_client_presentation_num;
+
+	b = dev->me_client_index;
+	b = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, b);
+	if (b < MEI_CLIENTS_MAX) {
+		dev->me_clients[client_num].client_id = b;
+		dev->me_clients[client_num].mei_flow_ctrl_creds = 0;
+		mei_header = (struct mei_msg_hdr *)&dev->wr_msg_buf[0];
+		mei_header->host_addr = 0;
+		mei_header->me_addr = 0;
+		mei_header->length = sizeof(struct hbm_props_request);
+		mei_header->msg_complete = 1;
+		mei_header->reserved = 0;
+
+		host_cli_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];
+
+		memset(host_cli_req, 0, sizeof(struct hbm_props_request));
+
+		host_cli_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
+		host_cli_req->address = b;
+
+		if (mei_write_message(dev, mei_header,
+				(unsigned char *)host_cli_req,
+				mei_header->length)) {
+			dev->mei_state = MEI_RESETING;
+			dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
+			mei_reset(dev, 1);
+			return -EIO;
+		}
+
+		dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
+		dev->me_client_index = b;
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * mei_init_file_private - initializes private file structure.
+ *
+ * @priv: private file structure to be initialized
+ * @file: the file structure
+ */
+void mei_cl_init(struct mei_cl *priv, struct mei_device *dev)
+{
+	memset(priv, 0, sizeof(struct mei_cl));
+	init_waitqueue_head(&priv->wait);
+	init_waitqueue_head(&priv->rx_wait);
+	init_waitqueue_head(&priv->tx_wait);
+	INIT_LIST_HEAD(&priv->link);
+	priv->reading_state = MEI_IDLE;
+	priv->writing_state = MEI_IDLE;
+	priv->dev = dev;
+}
+
+int mei_find_me_client_index(const struct mei_device *dev, uuid_le cuuid)
+{
+	int i, res = -1;
+
+	for (i = 0; i < dev->me_clients_num; ++i)
+		if (uuid_le_cmp(cuuid,
+				dev->me_clients[i].props.protocol_name) == 0) {
+			res = i;
+			break;
+		}
+
+	return res;
+}
+
+
+/**
+ * mei_find_me_client_update_filext - searches for ME client guid
+ *                       sets client_id in mei_file_private if found
+ * @dev: the device structure
+ * @priv: private file structure to set client_id in
+ * @cguid: searched guid of ME client
+ * @client_id: id of host client to be set in file private structure
+ *
+ * returns ME client index
+ */
+u8 mei_find_me_client_update_filext(struct mei_device *dev, struct mei_cl *priv,
+				const uuid_le *cguid, u8 client_id)
+{
+	int i;
+
+	if (!dev || !priv || !cguid)
+		return 0;
+
+	/* check for valid client id */
+	i = mei_find_me_client_index(dev, *cguid);
+	if (i >= 0) {
+		priv->me_client_id = dev->me_clients[i].client_id;
+		priv->state = MEI_FILE_CONNECTING;
+		priv->host_client_id = client_id;
+
+		list_add_tail(&priv->link, &dev->file_list);
+		return (u8)i;
+	}
+
+	return 0;
+}
+
+/**
+ * host_init_iamthif - mei initialization iamthif client.
+ *
+ * @dev: the device structure
+ *
+ */
+void mei_host_init_iamthif(struct mei_device *dev)
+{
+	u8 i;
+	unsigned char *msg_buf;
+
+	mei_cl_init(&dev->iamthif_cl, dev);
+	dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
+
+	/* find ME amthi client */
+	i = mei_find_me_client_update_filext(dev, &dev->iamthif_cl,
+			    &mei_amthi_guid, MEI_IAMTHIF_HOST_CLIENT_ID);
+	if (dev->iamthif_cl.state != MEI_FILE_CONNECTING) {
+		dev_dbg(&dev->pdev->dev, "failed to find iamthif client.\n");
+		return;
+	}
+
+	/* Assign iamthif_mtu to the value received from ME  */
+
+	dev->iamthif_mtu = dev->me_clients[i].props.max_msg_length;
+	dev_dbg(&dev->pdev->dev, "IAMTHIF_MTU = %d\n",
+			dev->me_clients[i].props.max_msg_length);
+
+	kfree(dev->iamthif_msg_buf);
+	dev->iamthif_msg_buf = NULL;
+
+	/* allocate storage for ME message buffer */
+	msg_buf = kcalloc(dev->iamthif_mtu,
+			sizeof(unsigned char), GFP_KERNEL);
+	if (!msg_buf) {
+		dev_dbg(&dev->pdev->dev, "memory allocation for ME message buffer failed.\n");
+		return;
+	}
+
+	dev->iamthif_msg_buf = msg_buf;
+
+	if (mei_connect(dev, &dev->iamthif_cl)) {
+		dev_dbg(&dev->pdev->dev, "Failed to connect to AMTHI client\n");
+		dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
+		dev->iamthif_cl.host_client_id = 0;
+	} else {
+		dev->iamthif_cl.timer_count = CONNECT_TIMEOUT;
+	}
+}
+
+/**
+ * mei_alloc_file_private - allocates a private file structure and sets it up.
+ * @file: the file structure
+ *
+ * returns  The allocated file or NULL on failure
+ */
+struct mei_cl *mei_cl_allocate(struct mei_device *dev)
+{
+	struct mei_cl *cl;
+
+	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
+	if (!cl)
+		return NULL;
+
+	mei_cl_init(cl, dev);
+
+	return cl;
+}
+
+
+
+/**
+ * mei_disconnect_host_client - sends disconnect message to fw from host client.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * returns 0 on success, <0 on failure.
+ */
+int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
+{
+	int rets, err;
+	long timeout = 15;	/* 15 seconds */
+	struct mei_cl_cb *cb;
+
+	if (!dev || !cl)
+		return -ENODEV;
+
+	if (cl->state != MEI_FILE_DISCONNECTING)
+		return 0;
+
+	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+	if (!cb)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&cb->cb_list);
+	cb->file_private = cl;
+	cb->major_file_operations = MEI_CLOSE;
+	if (dev->mei_host_buffer_is_empty) {
+		dev->mei_host_buffer_is_empty = false;
+		if (mei_disconnect(dev, cl)) {
+			rets = -ENODEV;
+			dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
+			goto free;
+		}
+		mdelay(10); /* Wait for hardware disconnection ready */
+		list_add_tail(&cb->cb_list, &dev->ctrl_rd_list.mei_cb.cb_list);
+	} else {
+		dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
+		list_add_tail(&cb->cb_list,
+				&dev->ctrl_wr_list.mei_cb.cb_list);
+	}
+	mutex_unlock(&dev->device_lock);
+
+	err = wait_event_timeout(dev->wait_recvd_msg,
+		 (MEI_FILE_DISCONNECTED == cl->state),
+		 timeout * HZ);
+
+	mutex_lock(&dev->device_lock);
+	if (MEI_FILE_DISCONNECTED == cl->state) {
+		rets = 0;
+		dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
+	} else {
+		rets = -ENODEV;
+		if (MEI_FILE_DISCONNECTED != cl->state)
+			dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");
+
+		if (err)
+			dev_dbg(&dev->pdev->dev,
+					"wait failed disconnect err=%08x\n",
+					err);
+
+		dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
+	}
+
+	mei_io_list_flush(&dev->ctrl_rd_list, cl);
+	mei_io_list_flush(&dev->ctrl_wr_list, cl);
+free:
+	mei_free_cb_private(cb);
+	return rets;
+}
+
+/**
+ * mei_remove_client_from_file_list -
+ *	removes file private data from device file list
+ *
+ * @dev: the device structure
+ * @host_client_id: host client id to be removed
+ */
+void mei_remove_client_from_file_list(struct mei_device *dev,
+				       u8 host_client_id)
+{
+	struct mei_cl *cl_pos = NULL;
+	struct mei_cl *cl_next = NULL;
+	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
+		if (host_client_id == cl_pos->host_client_id) {
+			dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
+					cl_pos->host_client_id,
+					cl_pos->me_client_id);
+			list_del_init(&cl_pos->link);
+			break;
+		}
+	}
+}

drivers/misc/mei/interface.c

@@ -0,0 +1,428 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#include <linux/pci.h>
+#include "mei_dev.h"
+#include "mei.h"
+#include "interface.h"
+
+
+
+/**
+ * mei_set_csr_register - writes H_CSR register to the mei device,
+ * and ignores the H_IS bit for it is write-one-to-zero.
+ *
+ * @dev: the device structure
+ */
+void mei_hcsr_set(struct mei_device *dev)
+{
+	if ((dev->host_hw_state & H_IS) == H_IS)
+		dev->host_hw_state &= ~H_IS;
+	mei_reg_write(dev, H_CSR, dev->host_hw_state);
+	dev->host_hw_state = mei_hcsr_read(dev);
+}
+
+/**
+ * mei_csr_enable_interrupts - enables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+void mei_enable_interrupts(struct mei_device *dev)
+{
+	dev->host_hw_state |= H_IE;
+	mei_hcsr_set(dev);
+}
+
+/**
+ * mei_csr_disable_interrupts - disables mei device interrupts
+ *
+ * @dev: the device structure
+ */
+void mei_disable_interrupts(struct mei_device *dev)
+{
+	dev->host_hw_state &= ~H_IE;
+	mei_hcsr_set(dev);
+}
+
+/**
+ * _host_get_filled_slots - gets number of device filled buffer slots
+ *
+ * @device: the device structure
+ *
+ * returns number of filled slots
+ */
+static unsigned char _host_get_filled_slots(const struct mei_device *dev)
+{
+	char read_ptr, write_ptr;
+
+	read_ptr = (char) ((dev->host_hw_state & H_CBRP) >> 8);
+	write_ptr = (char) ((dev->host_hw_state & H_CBWP) >> 16);
+
+	return (unsigned char) (write_ptr - read_ptr);
+}
+
+/**
+ * mei_host_buffer_is_empty - checks if host buffer is empty.
+ *
+ * @dev: the device structure
+ *
+ * returns 1 if empty, 0 - otherwise.
+ */
+int mei_host_buffer_is_empty(struct mei_device *dev)
+{
+	unsigned char filled_slots;
+
+	dev->host_hw_state = mei_hcsr_read(dev);
+	filled_slots = _host_get_filled_slots(dev);
+
+	if (filled_slots == 0)
+		return 1;
+
+	return 0;
+}
+
+/**
+ * mei_count_empty_write_slots - counts write empty slots.
+ *
+ * @dev: the device structure
+ *
+ * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise empty slots count
+ */
+int mei_count_empty_write_slots(struct mei_device *dev)
+{
+	unsigned char buffer_depth, filled_slots, empty_slots;
+
+	dev->host_hw_state = mei_hcsr_read(dev);
+	buffer_depth = (unsigned char) ((dev->host_hw_state & H_CBD) >> 24);
+	filled_slots = _host_get_filled_slots(dev);
+	empty_slots = buffer_depth - filled_slots;
+
+	/* check for overflow */
+	if (filled_slots > buffer_depth)
+		return -EOVERFLOW;
+
+	return empty_slots;
+}
+
+/**
+ * mei_write_message - writes a message to mei device.
+ *
+ * @dev: the device structure
+ * @header: header of message
+ * @write_buffer: message buffer will be written
+ * @write_length: message size will be written
+ *
+ * This function returns -EIO if write has failed
+ */
+int mei_write_message(struct mei_device *dev,
+		      struct mei_msg_hdr *header,
+		      unsigned char *write_buffer,
+		      unsigned long write_length)
+{
+	u32 temp_msg = 0;
+	unsigned long bytes_written = 0;
+	unsigned char buffer_depth, filled_slots, empty_slots;
+	unsigned long dw_to_write;
+
+	dev->host_hw_state = mei_hcsr_read(dev);
+
+	dev_dbg(&dev->pdev->dev,
+			"host_hw_state = 0x%08x.\n",
+			dev->host_hw_state);
+
+	dev_dbg(&dev->pdev->dev,
+			"mei_write_message header=%08x.\n",
+			*((u32 *) header));
+
+	buffer_depth = (unsigned char) ((dev->host_hw_state & H_CBD) >> 24);
+	filled_slots = _host_get_filled_slots(dev);
+	empty_slots = buffer_depth - filled_slots;
+	dev_dbg(&dev->pdev->dev,
+			"filled = %hu, empty = %hu.\n",
+			filled_slots, empty_slots);
+
+	dw_to_write = ((write_length + 3) / 4);
+
+	if (dw_to_write > empty_slots)
+		return -EIO;
+
+	mei_reg_write(dev, H_CB_WW, *((u32 *) header));
+
+	while (write_length >= 4) {
+		mei_reg_write(dev, H_CB_WW,
+				*(u32 *) (write_buffer + bytes_written));
+		bytes_written += 4;
+		write_length -= 4;
+	}
+
+	if (write_length > 0) {
+		memcpy(&temp_msg, &write_buffer[bytes_written], write_length);
+		mei_reg_write(dev, H_CB_WW, temp_msg);
+	}
+
+	dev->host_hw_state |= H_IG;
+	mei_hcsr_set(dev);
+	dev->me_hw_state = mei_mecsr_read(dev);
+	if ((dev->me_hw_state & ME_RDY_HRA) != ME_RDY_HRA)
+		return -EIO;
+
+	return 0;
+}
+
+/**
+ * mei_count_full_read_slots - counts read full slots.
+ *
+ * @dev: the device structure
+ *
+ * returns -1(ESLOTS_OVERFLOW) if overflow, otherwise filled slots count
+ */
+int mei_count_full_read_slots(struct mei_device *dev)
+{
+	char read_ptr, write_ptr;
+	unsigned char buffer_depth, filled_slots;
+
+	dev->me_hw_state = mei_mecsr_read(dev);
+	buffer_depth = (unsigned char)((dev->me_hw_state & ME_CBD_HRA) >> 24);
+	read_ptr = (char) ((dev->me_hw_state & ME_CBRP_HRA) >> 8);
+	write_ptr = (char) ((dev->me_hw_state & ME_CBWP_HRA) >> 16);
+	filled_slots = (unsigned char) (write_ptr - read_ptr);
+
+	/* check for overflow */
+	if (filled_slots > buffer_depth)
+		return -EOVERFLOW;
+
+	dev_dbg(&dev->pdev->dev, "filled_slots =%08x\n", filled_slots);
+	return (int)filled_slots;
+}
+
+/**
+ * mei_read_slots - reads a message from mei device.
+ *
+ * @dev: the device structure
+ * @buffer: message buffer will be written
+ * @buffer_length: message size will be read
+ */
+void mei_read_slots(struct mei_device *dev, unsigned char *buffer,
+		    unsigned long buffer_length)
+{
+	u32 *reg_buf = (u32 *)buffer;
+
+	for (; buffer_length >= sizeof(u32); buffer_length -= sizeof(u32))
+		*reg_buf++ = mei_mecbrw_read(dev);
+
+	if (buffer_length > 0) {
+		u32 reg = mei_mecbrw_read(dev);
+		memcpy(reg_buf, &reg, buffer_length);
+	}
+
+	dev->host_hw_state |= H_IG;
+	mei_hcsr_set(dev);
+}
+
+/**
+ * mei_flow_ctrl_creds - checks flow_control credentials.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * returns 1 if mei_flow_ctrl_creds >0, 0 - otherwise.
+ *	-ENOENT if mei_cl is not present
+ *	-EINVAL if single_recv_buf == 0
+ */
+int mei_flow_ctrl_creds(struct mei_device *dev, struct mei_cl *cl)
+{
+	int i;
+
+	if (!dev->me_clients_num)
+		return 0;
+
+	if (cl->mei_flow_ctrl_creds > 0)
+		return 1;
+
+	for (i = 0; i < dev->me_clients_num; i++) {
+		struct mei_me_client  *me_cl = &dev->me_clients[i];
+		if (me_cl->client_id == cl->me_client_id) {
+			if (me_cl->mei_flow_ctrl_creds) {
+				if (WARN_ON(me_cl->props.single_recv_buf == 0))
+					return -EINVAL;
+				return 1;
+			} else {
+				return 0;
+			}
+		}
+	}
+	return -ENOENT;
+}
+
+/**
+ * mei_flow_ctrl_reduce - reduces flow_control.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ * @returns
+ *	0 on success
+ *	-ENOENT when me client is not found
+ *	-EINVAL when ctrl credits are <= 0
+ */
+int mei_flow_ctrl_reduce(struct mei_device *dev, struct mei_cl *cl)
+{
+	int i;
+
+	if (!dev->me_clients_num)
+		return -ENOENT;
+
+	for (i = 0; i < dev->me_clients_num; i++) {
+		struct mei_me_client  *me_cl = &dev->me_clients[i];
+		if (me_cl->client_id == cl->me_client_id) {
+			if (me_cl->props.single_recv_buf != 0) {
+				if (WARN_ON(me_cl->mei_flow_ctrl_creds <= 0))
+					return -EINVAL;
+				dev->me_clients[i].mei_flow_ctrl_creds--;
+			} else {
+				if (WARN_ON(cl->mei_flow_ctrl_creds <= 0))
+					return -EINVAL;
+				cl->mei_flow_ctrl_creds--;
+			}
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+/**
+ * mei_send_flow_control - sends flow control to fw.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * This function returns -EIO on write failure
+ */
+int mei_send_flow_control(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct hbm_flow_control *mei_flow_control;
+
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	mei_hdr->host_addr = 0;
+	mei_hdr->me_addr = 0;
+	mei_hdr->length = sizeof(struct hbm_flow_control);
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	mei_flow_control = (struct hbm_flow_control *) &dev->wr_msg_buf[1];
+	memset(mei_flow_control, 0, sizeof(*mei_flow_control));
+	mei_flow_control->host_addr = cl->host_client_id;
+	mei_flow_control->me_addr = cl->me_client_id;
+	mei_flow_control->hbm_cmd = MEI_FLOW_CONTROL_CMD;
+	memset(mei_flow_control->reserved, 0,
+			sizeof(mei_flow_control->reserved));
+	dev_dbg(&dev->pdev->dev, "sending flow control host client = %d, ME client = %d\n",
+		cl->host_client_id, cl->me_client_id);
+
+	return mei_write_message(dev, mei_hdr,
+				(unsigned char *) mei_flow_control,
+				sizeof(struct hbm_flow_control));
+}
+
+/**
+ * mei_other_client_is_connecting - checks if other
+ *    client with the same client id is connected.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * returns 1 if other client is connected, 0 - otherwise.
+ */
+int mei_other_client_is_connecting(struct mei_device *dev,
+				struct mei_cl *cl)
+{
+	struct mei_cl *cl_pos = NULL;
+	struct mei_cl *cl_next = NULL;
+
+	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
+		if ((cl_pos->state == MEI_FILE_CONNECTING) &&
+			(cl_pos != cl) &&
+			cl->me_client_id == cl_pos->me_client_id)
+			return 1;
+
+	}
+	return 0;
+}
+
+/**
+ * mei_disconnect - sends disconnect message to fw.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * This function returns -EIO on write failure
+ */
+int mei_disconnect(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct hbm_client_disconnect_request *mei_cli_disconnect;
+
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	mei_hdr->host_addr = 0;
+	mei_hdr->me_addr = 0;
+	mei_hdr->length = sizeof(struct hbm_client_disconnect_request);
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	mei_cli_disconnect =
+	    (struct hbm_client_disconnect_request *) &dev->wr_msg_buf[1];
+	memset(mei_cli_disconnect, 0, sizeof(*mei_cli_disconnect));
+	mei_cli_disconnect->host_addr = cl->host_client_id;
+	mei_cli_disconnect->me_addr = cl->me_client_id;
+	mei_cli_disconnect->hbm_cmd = CLIENT_DISCONNECT_REQ_CMD;
+	mei_cli_disconnect->reserved[0] = 0;
+
+	return mei_write_message(dev, mei_hdr,
+				(unsigned char *) mei_cli_disconnect,
+				sizeof(struct hbm_client_disconnect_request));
+}
+
+/**
+ * mei_connect - sends connect message to fw.
+ *
+ * @dev: the device structure
+ * @cl: private data of the file object
+ *
+ * This function returns -EIO on write failure
+ */
+int mei_connect(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_msg_hdr *mei_hdr;
+	struct hbm_client_connect_request *mei_cli_connect;
+
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	mei_hdr->host_addr = 0;
+	mei_hdr->me_addr = 0;
+	mei_hdr->length = sizeof(struct hbm_client_connect_request);
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	mei_cli_connect =
+	    (struct hbm_client_connect_request *) &dev->wr_msg_buf[1];
+	mei_cli_connect->host_addr = cl->host_client_id;
+	mei_cli_connect->me_addr = cl->me_client_id;
+	mei_cli_connect->hbm_cmd = CLIENT_CONNECT_REQ_CMD;
+	mei_cli_connect->reserved = 0;
+
+	return mei_write_message(dev, mei_hdr,
+				(unsigned char *) mei_cli_connect,
+				sizeof(struct hbm_client_connect_request));
+}

drivers/misc/mei/interface.h

@@ -0,0 +1,75 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+
+
+#ifndef _MEI_INTERFACE_H_
+#define _MEI_INTERFACE_H_
+
+#include "mei.h"
+#include "mei_dev.h"
+
+
+#define AMT_WD_DEFAULT_TIMEOUT 120	/* seconds */
+#define AMT_WD_MIN_TIMEOUT 120	/* seconds */
+#define AMT_WD_MAX_TIMEOUT 65535	/* seconds */
+
+#define MEI_WATCHDOG_DATA_SIZE         16
+#define MEI_START_WD_DATA_SIZE         20
+#define MEI_WD_PARAMS_SIZE             4
+
+
+void mei_read_slots(struct mei_device *dev,
+		     unsigned char *buffer,
+		     unsigned long buffer_length);
+
+int mei_write_message(struct mei_device *dev,
+			     struct mei_msg_hdr *header,
+			     unsigned char *write_buffer,
+			     unsigned long write_length);
+
+int mei_host_buffer_is_empty(struct mei_device *dev);
+
+int mei_count_full_read_slots(struct mei_device *dev);
+
+int mei_count_empty_write_slots(struct mei_device *dev);
+
+int mei_flow_ctrl_creds(struct mei_device *dev, struct mei_cl *cl);
+
+int mei_wd_send(struct mei_device *dev);
+int mei_wd_stop(struct mei_device *dev, bool preserve);
+int mei_wd_host_init(struct mei_device *dev);
+/*
+ * mei_watchdog_register  - Registering watchdog interface
+ *   once we got connection to the WD Client
+ * @dev - mei device
+ */
+void mei_watchdog_register(struct mei_device *dev);
+/*
+ * mei_watchdog_unregister  - Unregistering watchdog interface
+ * @dev - mei device
+ */
+void mei_watchdog_unregister(struct mei_device *dev);
+
+int mei_flow_ctrl_reduce(struct mei_device *dev, struct mei_cl *cl);
+
+int mei_send_flow_control(struct mei_device *dev, struct mei_cl *cl);
+
+int mei_disconnect(struct mei_device *dev, struct mei_cl *cl);
+int mei_other_client_is_connecting(struct mei_device *dev, struct mei_cl *cl);
+int mei_connect(struct mei_device *dev, struct mei_cl *cl);
+
+#endif /* _MEI_INTERFACE_H_ */

drivers/misc/mei/iorw.c

@@ -0,0 +1,590 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/aio.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ioctl.h>
+#include <linux/cdev.h>
+#include <linux/list.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/uuid.h>
+#include <linux/jiffies.h>
+#include <linux/uaccess.h>
+
+
+#include "mei_dev.h"
+#include "hw.h"
+#include "mei.h"
+#include "interface.h"
+
+
+
+/**
+ * mei_ioctl_connect_client - the connect to fw client IOCTL function
+ *
+ * @dev: the device structure
+ * @data: IOCTL connect data, input and output parameters
+ * @file: private data of the file object
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * returns 0 on success, <0 on failure.
+ */
+int mei_ioctl_connect_client(struct file *file,
+			struct mei_connect_client_data *data)
+{
+	struct mei_device *dev;
+	struct mei_cl_cb *cb;
+	struct mei_client *client;
+	struct mei_cl *cl;
+	struct mei_cl *cl_pos = NULL;
+	struct mei_cl *cl_next = NULL;
+	long timeout = CONNECT_TIMEOUT;
+	int i;
+	int err;
+	int rets;
+
+	cl = file->private_data;
+	if (WARN_ON(!cl || !cl->dev))
+		return -ENODEV;
+
+	dev = cl->dev;
+
+	dev_dbg(&dev->pdev->dev, "mei_ioctl_connect_client() Entry\n");
+
+
+	/* buffered ioctl cb */
+	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+	if (!cb) {
+		rets = -ENOMEM;
+		goto end;
+	}
+	INIT_LIST_HEAD(&cb->cb_list);
+
+	cb->major_file_operations = MEI_IOCTL;
+
+	if (dev->mei_state != MEI_ENABLED) {
+		rets = -ENODEV;
+		goto end;
+	}
+	if (cl->state != MEI_FILE_INITIALIZING &&
+	    cl->state != MEI_FILE_DISCONNECTED) {
+		rets = -EBUSY;
+		goto end;
+	}
+
+	/* find ME client we're trying to connect to */
+	i = mei_find_me_client_index(dev, data->in_client_uuid);
+	if (i >= 0 && !dev->me_clients[i].props.fixed_address) {
+		cl->me_client_id = dev->me_clients[i].client_id;
+		cl->state = MEI_FILE_CONNECTING;
+	}
+
+	dev_dbg(&dev->pdev->dev, "Connect to FW Client ID = %d\n",
+			cl->me_client_id);
+	dev_dbg(&dev->pdev->dev, "FW Client - Protocol Version = %d\n",
+			dev->me_clients[i].props.protocol_version);
+	dev_dbg(&dev->pdev->dev, "FW Client - Max Msg Len = %d\n",
+			dev->me_clients[i].props.max_msg_length);
+
+	/* if we're connecting to amthi client then we will use the
+	 * existing connection
+	 */
+	if (uuid_le_cmp(data->in_client_uuid, mei_amthi_guid) == 0) {
+		dev_dbg(&dev->pdev->dev, "FW Client is amthi\n");
+		if (dev->iamthif_cl.state != MEI_FILE_CONNECTED) {
+			rets = -ENODEV;
+			goto end;
+		}
+		clear_bit(cl->host_client_id, dev->host_clients_map);
+		list_for_each_entry_safe(cl_pos, cl_next,
+					 &dev->file_list, link) {
+			if (mei_cl_cmp_id(cl, cl_pos)) {
+				dev_dbg(&dev->pdev->dev,
+					"remove file private data node host"
+				    " client = %d, ME client = %d.\n",
+				    cl_pos->host_client_id,
+				    cl_pos->me_client_id);
+				list_del(&cl_pos->link);
+			}
+
+		}
+		dev_dbg(&dev->pdev->dev, "free file private data memory.\n");
+		kfree(cl);
+
+		cl = NULL;
+		file->private_data = &dev->iamthif_cl;
+
+		client = &data->out_client_properties;
+		client->max_msg_length =
+			dev->me_clients[i].props.max_msg_length;
+		client->protocol_version =
+			dev->me_clients[i].props.protocol_version;
+		rets = dev->iamthif_cl.status;
+
+		goto end;
+	}
+
+	if (cl->state != MEI_FILE_CONNECTING) {
+		rets = -ENODEV;
+		goto end;
+	}
+
+
+	/* prepare the output buffer */
+	client = &data->out_client_properties;
+	client->max_msg_length = dev->me_clients[i].props.max_msg_length;
+	client->protocol_version = dev->me_clients[i].props.protocol_version;
+	dev_dbg(&dev->pdev->dev, "Can connect?\n");
+	if (dev->mei_host_buffer_is_empty
+	    && !mei_other_client_is_connecting(dev, cl)) {
+		dev_dbg(&dev->pdev->dev, "Sending Connect Message\n");
+		dev->mei_host_buffer_is_empty = false;
+		if (mei_connect(dev, cl)) {
+			dev_dbg(&dev->pdev->dev, "Sending connect message - failed\n");
+			rets = -ENODEV;
+			goto end;
+		} else {
+			dev_dbg(&dev->pdev->dev, "Sending connect message - succeeded\n");
+			cl->timer_count = MEI_CONNECT_TIMEOUT;
+			cb->file_private = cl;
+			list_add_tail(&cb->cb_list,
+				      &dev->ctrl_rd_list.mei_cb.
+				      cb_list);
+		}
+
+
+	} else {
+		dev_dbg(&dev->pdev->dev, "Queuing the connect request due to device busy\n");
+		cb->file_private = cl;
+		dev_dbg(&dev->pdev->dev, "add connect cb to control write list.\n");
+		list_add_tail(&cb->cb_list,
+			      &dev->ctrl_wr_list.mei_cb.cb_list);
+	}
+	mutex_unlock(&dev->device_lock);
+	err = wait_event_timeout(dev->wait_recvd_msg,
+			(MEI_FILE_CONNECTED == cl->state ||
+			 MEI_FILE_DISCONNECTED == cl->state),
+			timeout * HZ);
+
+	mutex_lock(&dev->device_lock);
+	if (MEI_FILE_CONNECTED == cl->state) {
+		dev_dbg(&dev->pdev->dev, "successfully connected to FW client.\n");
+		rets = cl->status;
+		goto end;
+	} else {
+		dev_dbg(&dev->pdev->dev, "failed to connect to FW client.cl->state = %d.\n",
+		    cl->state);
+		if (!err) {
+			dev_dbg(&dev->pdev->dev,
+				"wait_event_interruptible_timeout failed on client"
+				" connect message fw response message.\n");
+		}
+		rets = -EFAULT;
+
+		mei_io_list_flush(&dev->ctrl_rd_list, cl);
+		mei_io_list_flush(&dev->ctrl_wr_list, cl);
+		goto end;
+	}
+	rets = 0;
+end:
+	dev_dbg(&dev->pdev->dev, "free connect cb memory.");
+	kfree(cb);
+	return rets;
+}
+
+/**
+ * find_amthi_read_list_entry - finds a amthilist entry for current file
+ *
+ * @dev: the device structure
+ * @file: pointer to file object
+ *
+ * returns   returned a list entry on success, NULL on failure.
+ */
+struct mei_cl_cb *find_amthi_read_list_entry(
+		struct mei_device *dev,
+		struct file *file)
+{
+	struct mei_cl *cl_temp;
+	struct mei_cl_cb *pos = NULL;
+	struct mei_cl_cb *next = NULL;
+
+	list_for_each_entry_safe(pos, next,
+	    &dev->amthi_read_complete_list.mei_cb.cb_list, cb_list) {
+		cl_temp = (struct mei_cl *)pos->file_private;
+		if (cl_temp && cl_temp == &dev->iamthif_cl &&
+			pos->file_object == file)
+			return pos;
+	}
+	return NULL;
+}
+
+/**
+ * amthi_read - read data from AMTHI client
+ *
+ * @dev: the device structure
+ * @if_num:  minor number
+ * @file: pointer to file object
+ * @*ubuf: pointer to user data in user space
+ * @length: data length to read
+ * @offset: data read offset
+ *
+ * Locking: called under "dev->device_lock" lock
+ *
+ * returns
+ *  returned data length on success,
+ *  zero if no data to read,
+ *  negative on failure.
+ */
+int amthi_read(struct mei_device *dev, struct file *file,
+	       char __user *ubuf, size_t length, loff_t *offset)
+{
+	int rets;
+	int wait_ret;
+	struct mei_cl_cb *cb = NULL;
+	struct mei_cl *cl = file->private_data;
+	unsigned long timeout;
+	int i;
+
+	/* Only Posible if we are in timeout */
+	if (!cl || cl != &dev->iamthif_cl) {
+		dev_dbg(&dev->pdev->dev, "bad file ext.\n");
+		return -ETIMEDOUT;
+	}
+
+	for (i = 0; i < dev->me_clients_num; i++) {
+		if (dev->me_clients[i].client_id ==
+		    dev->iamthif_cl.me_client_id)
+			break;
+	}
+
+	if (i == dev->me_clients_num) {
+		dev_dbg(&dev->pdev->dev, "amthi client not found.\n");
+		return -ENODEV;
+	}
+	if (WARN_ON(dev->me_clients[i].client_id != cl->me_client_id))
+		return -ENODEV;
+
+	dev_dbg(&dev->pdev->dev, "checking amthi data\n");
+	cb = find_amthi_read_list_entry(dev, file);
+
+	/* Check for if we can block or not*/
+	if (cb == NULL && file->f_flags & O_NONBLOCK)
+		return -EAGAIN;
+
+
+	dev_dbg(&dev->pdev->dev, "waiting for amthi data\n");
+	while (cb == NULL) {
+		/* unlock the Mutex */
+		mutex_unlock(&dev->device_lock);
+
+		wait_ret = wait_event_interruptible(dev->iamthif_cl.wait,
+			(cb = find_amthi_read_list_entry(dev, file)));
+
+		if (wait_ret)
+			return -ERESTARTSYS;
+
+		dev_dbg(&dev->pdev->dev, "woke up from sleep\n");
+
+		/* Locking again the Mutex */
+		mutex_lock(&dev->device_lock);
+	}
+
+
+	dev_dbg(&dev->pdev->dev, "Got amthi data\n");
+	dev->iamthif_timer = 0;
+
+	if (cb) {
+		timeout = cb->read_time +
+					msecs_to_jiffies(IAMTHIF_READ_TIMER);
+		dev_dbg(&dev->pdev->dev, "amthi timeout = %lud\n",
+				timeout);
+
+		if  (time_after(jiffies, timeout)) {
+			dev_dbg(&dev->pdev->dev, "amthi Time out\n");
+			/* 15 sec for the message has expired */
+			list_del(&cb->cb_list);
+			rets = -ETIMEDOUT;
+			goto free;
+		}
+	}
+	/* if the whole message will fit remove it from the list */
+	if (cb->information >= *offset && length >= (cb->information - *offset))
+		list_del(&cb->cb_list);
+	else if (cb->information > 0 && cb->information <= *offset) {
+		/* end of the message has been reached */
+		list_del(&cb->cb_list);
+		rets = 0;
+		goto free;
+	}
+		/* else means that not full buffer will be read and do not
+		 * remove message from deletion list
+		 */
+
+	dev_dbg(&dev->pdev->dev, "amthi cb->response_buffer size - %d\n",
+	    cb->response_buffer.size);
+	dev_dbg(&dev->pdev->dev, "amthi cb->information - %lu\n",
+	    cb->information);
+
+	/* length is being turncated to PAGE_SIZE, however,
+	 * the information may be longer */
+	length = min_t(size_t, length, (cb->information - *offset));
+
+	if (copy_to_user(ubuf, cb->response_buffer.data + *offset, length))
+		rets = -EFAULT;
+	else {
+		rets = length;
+		if ((*offset + length) < cb->information) {
+			*offset += length;
+			goto out;
+		}
+	}
+free:
+	dev_dbg(&dev->pdev->dev, "free amthi cb memory.\n");
+	*offset = 0;
+	mei_free_cb_private(cb);
+out:
+	return rets;
+}
+
+/**
+ * mei_start_read - the start read client message function.
+ *
+ * @dev: the device structure
+ * @if_num:  minor number
+ * @cl: private data of the file object
+ *
+ * returns 0 on success, <0 on failure.
+ */
+int mei_start_read(struct mei_device *dev, struct mei_cl *cl)
+{
+	struct mei_cl_cb *cb;
+	int rets = 0;
+	int i;
+
+	if (cl->state != MEI_FILE_CONNECTED)
+		return -ENODEV;
+
+	if (dev->mei_state != MEI_ENABLED)
+		return -ENODEV;
+
+	dev_dbg(&dev->pdev->dev, "check if read is pending.\n");
+	if (cl->read_pending || cl->read_cb) {
+		dev_dbg(&dev->pdev->dev, "read is pending.\n");
+		return -EBUSY;
+	}
+
+	cb = kzalloc(sizeof(struct mei_cl_cb), GFP_KERNEL);
+	if (!cb)
+		return -ENOMEM;
+
+	dev_dbg(&dev->pdev->dev, "allocation call back successful. host client = %d, ME client = %d\n",
+		cl->host_client_id, cl->me_client_id);
+
+	for (i = 0; i < dev->me_clients_num; i++) {
+		if (dev->me_clients[i].client_id == cl->me_client_id)
+			break;
+
+	}
+
+	if (WARN_ON(dev->me_clients[i].client_id != cl->me_client_id)) {
+		rets = -ENODEV;
+		goto unlock;
+	}
+
+	if (i == dev->me_clients_num) {
+		rets = -ENODEV;
+		goto unlock;
+	}
+
+	cb->response_buffer.size = dev->me_clients[i].props.max_msg_length;
+	cb->response_buffer.data =
+			kmalloc(cb->response_buffer.size, GFP_KERNEL);
+	if (!cb->response_buffer.data) {
+		rets = -ENOMEM;
+		goto unlock;
+	}
+	dev_dbg(&dev->pdev->dev, "allocation call back data success.\n");
+	cb->major_file_operations = MEI_READ;
+	/* make sure information is zero before we start */
+	cb->information = 0;
+	cb->file_private = (void *) cl;
+	cl->read_cb = cb;
+	if (dev->mei_host_buffer_is_empty) {
+		dev->mei_host_buffer_is_empty = false;
+		if (mei_send_flow_control(dev, cl)) {
+			rets = -ENODEV;
+			goto unlock;
+		}
+		list_add_tail(&cb->cb_list, &dev->read_list.mei_cb.cb_list);
+	} else {
+		list_add_tail(&cb->cb_list, &dev->ctrl_wr_list.mei_cb.cb_list);
+	}
+	return rets;
+unlock:
+	mei_free_cb_private(cb);
+	return rets;
+}
+
+/**
+ * amthi_write - write iamthif data to amthi client
+ *
+ * @dev: the device structure
+ * @cb: mei call back struct
+ *
+ * returns 0 on success, <0 on failure.
+ */
+int amthi_write(struct mei_device *dev, struct mei_cl_cb *cb)
+{
+	struct mei_msg_hdr mei_hdr;
+	int ret;
+
+	if (!dev || !cb)
+		return -ENODEV;
+
+	dev_dbg(&dev->pdev->dev, "write data to amthi client.\n");
+
+	dev->iamthif_state = MEI_IAMTHIF_WRITING;
+	dev->iamthif_current_cb = cb;
+	dev->iamthif_file_object = cb->file_object;
+	dev->iamthif_canceled = false;
+	dev->iamthif_ioctl = true;
+	dev->iamthif_msg_buf_size = cb->request_buffer.size;
+	memcpy(dev->iamthif_msg_buf, cb->request_buffer.data,
+	       cb->request_buffer.size);
+
+	ret = mei_flow_ctrl_creds(dev, &dev->iamthif_cl);
+	if (ret < 0)
+		return ret;
+
+	if (ret && dev->mei_host_buffer_is_empty) {
+		ret = 0;
+		dev->mei_host_buffer_is_empty = false;
+		if (cb->request_buffer.size >
+			(((dev->host_hw_state & H_CBD) >> 24) * sizeof(u32))
+				-sizeof(struct mei_msg_hdr)) {
+			mei_hdr.length =
+			    (((dev->host_hw_state & H_CBD) >> 24) *
+			    sizeof(u32)) - sizeof(struct mei_msg_hdr);
+			mei_hdr.msg_complete = 0;
+		} else {
+			mei_hdr.length = cb->request_buffer.size;
+			mei_hdr.msg_complete = 1;
+		}
+
+		mei_hdr.host_addr = dev->iamthif_cl.host_client_id;
+		mei_hdr.me_addr = dev->iamthif_cl.me_client_id;
+		mei_hdr.reserved = 0;
+		dev->iamthif_msg_buf_index += mei_hdr.length;
+		if (mei_write_message(dev, &mei_hdr,
+					(unsigned char *)(dev->iamthif_msg_buf),
+					mei_hdr.length))
+			return -ENODEV;
+
+		if (mei_hdr.msg_complete) {
+			if (mei_flow_ctrl_reduce(dev, &dev->iamthif_cl))
+				return -ENODEV;
+			dev->iamthif_flow_control_pending = true;
+			dev->iamthif_state = MEI_IAMTHIF_FLOW_CONTROL;
+			dev_dbg(&dev->pdev->dev, "add amthi cb to write waiting list\n");
+			dev->iamthif_current_cb = cb;
+			dev->iamthif_file_object = cb->file_object;
+			list_add_tail(&cb->cb_list,
+				      &dev->write_waiting_list.mei_cb.cb_list);
+		} else {
+			dev_dbg(&dev->pdev->dev, "message does not complete, "
+					"so add amthi cb to write list.\n");
+			list_add_tail(&cb->cb_list,
+				      &dev->write_list.mei_cb.cb_list);
+		}
+	} else {
+		if (!(dev->mei_host_buffer_is_empty))
+			dev_dbg(&dev->pdev->dev, "host buffer is not empty");
+
+		dev_dbg(&dev->pdev->dev, "No flow control credentials, "
+				"so add iamthif cb to write list.\n");
+		list_add_tail(&cb->cb_list, &dev->write_list.mei_cb.cb_list);
+	}
+	return 0;
+}
+
+/**
+ * iamthif_ioctl_send_msg - send cmd data to amthi client
+ *
+ * @dev: the device structure
+ *
+ * returns 0 on success, <0 on failure.
+ */
+void mei_run_next_iamthif_cmd(struct mei_device *dev)
+{
+	struct mei_cl *cl_tmp;
+	struct mei_cl_cb *pos = NULL;
+	struct mei_cl_cb *next = NULL;
+	int status;
+
+	if (!dev)
+		return;
+
+	dev->iamthif_msg_buf_size = 0;
+	dev->iamthif_msg_buf_index = 0;
+	dev->iamthif_canceled = false;
+	dev->iamthif_ioctl = true;
+	dev->iamthif_state = MEI_IAMTHIF_IDLE;
+	dev->iamthif_timer = 0;
+	dev->iamthif_file_object = NULL;
+
+	dev_dbg(&dev->pdev->dev, "complete amthi cmd_list cb.\n");
+
+	list_for_each_entry_safe(pos, next,
+			&dev->amthi_cmd_list.mei_cb.cb_list, cb_list) {
+		list_del(&pos->cb_list);
+		cl_tmp = (struct mei_cl *)pos->file_private;
+
+		if (cl_tmp && cl_tmp == &dev->iamthif_cl) {
+			status = amthi_write(dev, pos);
+			if (status) {
+				dev_dbg(&dev->pdev->dev,
+					"amthi write failed status = %d\n",
+						status);
+				return;
+			}
+			break;
+		}
+	}
+}
+
+/**
+ * mei_free_cb_private - free mei_cb_private related memory
+ *
+ * @cb: mei callback struct
+ */
+void mei_free_cb_private(struct mei_cl_cb *cb)
+{
+	if (cb == NULL)
+		return;
+
+	kfree(cb->request_buffer.data);
+	kfree(cb->response_buffer.data);
+	kfree(cb);
+}

drivers/misc/mei/mei-amt-version.c

@@ -0,0 +1,481 @@
+/******************************************************************************
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Intel MEI Interface Header
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ *	Intel Corporation.
+ *	linux-mei@linux.intel.com
+ *	http://www.intel.com
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *****************************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <bits/wordsize.h>
+#include "mei.h"
+
+/*****************************************************************************
+ * Intel Management Engine Interface
+ *****************************************************************************/
+
+#define mei_msg(_me, fmt, ARGS...) do {         \
+	if (_me->verbose)                       \
+		fprintf(stderr, fmt, ##ARGS);	\
+} while (0)
+
+#define mei_err(_me, fmt, ARGS...) do {         \
+	fprintf(stderr, "Error: " fmt, ##ARGS); \
+} while (0)
+
+struct mei {
+	uuid_le guid;
+	bool initialized;
+	bool verbose;
+	unsigned int buf_size;
+	unsigned char prot_ver;
+	int fd;
+};
+
+static void mei_deinit(struct mei *cl)
+{
+	if (cl->fd != -1)
+		close(cl->fd);
+	cl->fd = -1;
+	cl->buf_size = 0;
+	cl->prot_ver = 0;
+	cl->initialized = false;
+}
+
+static bool mei_init(struct mei *me, const uuid_le *guid,
+		unsigned char req_protocol_version, bool verbose)
+{
+	int result;
+	struct mei_client *cl;
+	struct mei_connect_client_data data;
+
+	mei_deinit(me);
+
+	me->verbose = verbose;
+
+	me->fd = open("/dev/mei", O_RDWR);
+	if (me->fd == -1) {
+		mei_err(me, "Cannot establish a handle to the Intel MEI driver\n");
+		goto err;
+	}
+	memcpy(&me->guid, guid, sizeof(*guid));
+	memset(&data, 0, sizeof(data));
+	me->initialized = true;
+
+	memcpy(&data.in_client_uuid, &me->guid, sizeof(me->guid));
+	result = ioctl(me->fd, IOCTL_MEI_CONNECT_CLIENT, &data);
+	if (result) {
+		mei_err(me, "IOCTL_MEI_CONNECT_CLIENT receive message. err=%d\n", result);
+		goto err;
+	}
+	cl = &data.out_client_properties;
+	mei_msg(me, "max_message_length %d\n", cl->max_msg_length);
+	mei_msg(me, "protocol_version %d\n", cl->protocol_version);
+
+	if ((req_protocol_version > 0) &&
+	     (cl->protocol_version != req_protocol_version)) {
+		mei_err(me, "Intel MEI protocol version not supported\n");
+		goto err;
+	}
+
+	me->buf_size = cl->max_msg_length;
+	me->prot_ver = cl->protocol_version;
+
+	return true;
+err:
+	mei_deinit(me);
+	return false;
+}
+
+static ssize_t mei_recv_msg(struct mei *me, unsigned char *buffer,
+			ssize_t len, unsigned long timeout)
+{
+	ssize_t rc;
+
+	mei_msg(me, "call read length = %zd\n", len);
+
+	rc = read(me->fd, buffer, len);
+	if (rc < 0) {
+		mei_err(me, "read failed with status %zd %s\n",
+				rc, strerror(errno));
+		mei_deinit(me);
+	} else {
+		mei_msg(me, "read succeeded with result %zd\n", rc);
+	}
+	return rc;
+}
+
+static ssize_t mei_send_msg(struct mei *me, const unsigned char *buffer,
+			ssize_t len, unsigned long timeout)
+{
+	struct timeval tv;
+	ssize_t written;
+	ssize_t rc;
+	fd_set set;
+
+	tv.tv_sec = timeout / 1000;
+	tv.tv_usec = (timeout % 1000) * 1000000;
+
+	mei_msg(me, "call write length = %zd\n", len);
+
+	written = write(me->fd, buffer, len);
+	if (written < 0) {
+		rc = -errno;
+		mei_err(me, "write failed with status %zd %s\n",
+			written, strerror(errno));
+		goto out;
+	}
+
+	FD_ZERO(&set);
+	FD_SET(me->fd, &set);
+	rc = select(me->fd + 1 , &set, NULL, NULL, &tv);
+	if (rc > 0 && FD_ISSET(me->fd, &set)) {
+		mei_msg(me, "write success\n");
+	} else if (rc == 0) {
+		mei_err(me, "write failed on timeout with status\n");
+		goto out;
+	} else { /* rc < 0 */
+		mei_err(me, "write failed on select with status %zd\n", rc);
+		goto out;
+	}
+
+	rc = written;
+out:
+	if (rc < 0)
+		mei_deinit(me);
+
+	return rc;
+}
+
+/***************************************************************************
+ * Intel Advanced Management Technolgy ME Client
+ ***************************************************************************/
+
+#define AMT_MAJOR_VERSION 1
+#define AMT_MINOR_VERSION 1
+
+#define AMT_STATUS_SUCCESS                0x0
+#define AMT_STATUS_INTERNAL_ERROR         0x1
+#define AMT_STATUS_NOT_READY              0x2
+#define AMT_STATUS_INVALID_AMT_MODE       0x3
+#define AMT_STATUS_INVALID_MESSAGE_LENGTH 0x4
+
+#define AMT_STATUS_HOST_IF_EMPTY_RESPONSE  0x4000
+#define AMT_STATUS_SDK_RESOURCES      0x1004
+
+
+#define AMT_BIOS_VERSION_LEN   65
+#define AMT_VERSIONS_NUMBER    50
+#define AMT_UNICODE_STRING_LEN 20
+
+struct amt_unicode_string {
+	uint16_t length;
+	char string[AMT_UNICODE_STRING_LEN];
+} __attribute__((packed));
+
+struct amt_version_type {
+	struct amt_unicode_string description;
+	struct amt_unicode_string version;
+} __attribute__((packed));
+
+struct amt_version {
+	uint8_t major;
+	uint8_t minor;
+} __attribute__((packed));
+
+struct amt_code_versions {
+	uint8_t bios[AMT_BIOS_VERSION_LEN];
+	uint32_t count;
+	struct amt_version_type versions[AMT_VERSIONS_NUMBER];
+} __attribute__((packed));
+
+/***************************************************************************
+ * Intel Advanced Management Technolgy Host Interface
+ ***************************************************************************/
+
+struct amt_host_if_msg_header {
+	struct amt_version version;
+	uint16_t _reserved;
+	uint32_t command;
+	uint32_t length;
+} __attribute__((packed));
+
+struct amt_host_if_resp_header {
+	struct amt_host_if_msg_header header;
+	uint32_t status;
+	unsigned char data[0];
+} __attribute__((packed));
+
+const uuid_le MEI_IAMTHIF = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,  \
+				0xac, 0xa8, 0x46, 0xe0, 0xff, 0x65, 0x81, 0x4c);
+
+#define AMT_HOST_IF_CODE_VERSIONS_REQUEST  0x0400001A
+#define AMT_HOST_IF_CODE_VERSIONS_RESPONSE 0x0480001A
+
+const struct amt_host_if_msg_header CODE_VERSION_REQ = {
+	.version = {AMT_MAJOR_VERSION, AMT_MINOR_VERSION},
+	._reserved = 0,
+	.command = AMT_HOST_IF_CODE_VERSIONS_REQUEST,
+	.length = 0
+};
+
+
+struct amt_host_if {
+	struct mei mei_cl;
+	unsigned long send_timeout;
+	bool initialized;
+};
+
+
+static bool amt_host_if_init(struct amt_host_if *acmd,
+		      unsigned long send_timeout, bool verbose)
+{
+	acmd->send_timeout = (send_timeout) ? send_timeout : 20000;
+	acmd->initialized = mei_init(&acmd->mei_cl, &MEI_IAMTHIF, 0, verbose);
+	return acmd->initialized;
+}
+
+static void amt_host_if_deinit(struct amt_host_if *acmd)
+{
+	mei_deinit(&acmd->mei_cl);
+	acmd->initialized = false;
+}
+
+static uint32_t amt_verify_code_versions(const struct amt_host_if_resp_header *resp)
+{
+	uint32_t status = AMT_STATUS_SUCCESS;
+	struct amt_code_versions *code_ver;
+	size_t code_ver_len;
+	uint32_t ver_type_cnt;
+	uint32_t len;
+	uint32_t i;
+
+	code_ver = (struct amt_code_versions *)resp->data;
+	/* length - sizeof(status) */
+	code_ver_len = resp->header.length - sizeof(uint32_t);
+	ver_type_cnt = code_ver_len -
+			sizeof(code_ver->bios) -
+			sizeof(code_ver->count);
+	if (code_ver->count != ver_type_cnt / sizeof(struct amt_version_type)) {
+		status = AMT_STATUS_INTERNAL_ERROR;
+		goto out;
+	}
+
+	for (i = 0; i < code_ver->count; i++) {
+		len = code_ver->versions[i].description.length;
+
+		if (len > AMT_UNICODE_STRING_LEN) {
+			status = AMT_STATUS_INTERNAL_ERROR;
+			goto out;
+		}
+
+		len = code_ver->versions[i].version.length;
+		if (code_ver->versions[i].version.string[len] != '\0' ||
+		    len != strlen(code_ver->versions[i].version.string)) {
+			status = AMT_STATUS_INTERNAL_ERROR;
+			goto out;
+		}
+	}
+out:
+	return status;
+}
+
+static uint32_t amt_verify_response_header(uint32_t command,
+				const struct amt_host_if_msg_header *resp_hdr,
+				uint32_t response_size)
+{
+	if (response_size < sizeof(struct amt_host_if_resp_header)) {
+		return AMT_STATUS_INTERNAL_ERROR;
+	} else if (response_size != (resp_hdr->length +
+				sizeof(struct amt_host_if_msg_header))) {
+		return AMT_STATUS_INTERNAL_ERROR;
+	} else if (resp_hdr->command != command) {
+		return AMT_STATUS_INTERNAL_ERROR;
+	} else if (resp_hdr->_reserved != 0) {
+		return AMT_STATUS_INTERNAL_ERROR;
+	} else if (resp_hdr->version.major != AMT_MAJOR_VERSION ||
+		   resp_hdr->version.minor < AMT_MINOR_VERSION) {
+		return AMT_STATUS_INTERNAL_ERROR;
+	}
+	return AMT_STATUS_SUCCESS;
+}
+
+static uint32_t amt_host_if_call(struct amt_host_if *acmd,
+			const unsigned char *command, ssize_t command_sz,
+			uint8_t **read_buf, uint32_t rcmd,
+			unsigned int expected_sz)
+{
+	uint32_t in_buf_sz;
+	uint32_t out_buf_sz;
+	ssize_t written;
+	uint32_t status;
+	struct amt_host_if_resp_header *msg_hdr;
+
+	in_buf_sz = acmd->mei_cl.buf_size;
+	*read_buf = (uint8_t *)malloc(sizeof(uint8_t) * in_buf_sz);
+	if (*read_buf == NULL)
+		return AMT_STATUS_SDK_RESOURCES;
+	memset(*read_buf, 0, in_buf_sz);
+	msg_hdr = (struct amt_host_if_resp_header *)*read_buf;
+
+	written = mei_send_msg(&acmd->mei_cl,
+				command, command_sz, acmd->send_timeout);
+	if (written != command_sz)
+		return AMT_STATUS_INTERNAL_ERROR;
+
+	out_buf_sz = mei_recv_msg(&acmd->mei_cl, *read_buf, in_buf_sz, 2000);
+	if (out_buf_sz <= 0)
+		return AMT_STATUS_HOST_IF_EMPTY_RESPONSE;
+
+	status = msg_hdr->status;
+	if (status != AMT_STATUS_SUCCESS)
+		return status;
+
+	status = amt_verify_response_header(rcmd,
+				&msg_hdr->header, out_buf_sz);
+	if (status != AMT_STATUS_SUCCESS)
+		return status;
+
+	if (expected_sz && expected_sz != out_buf_sz)
+		return AMT_STATUS_INTERNAL_ERROR;
+
+	return AMT_STATUS_SUCCESS;
+}
+
+
+static uint32_t amt_get_code_versions(struct amt_host_if *cmd,
+			       struct amt_code_versions *versions)
+{
+	struct amt_host_if_resp_header *response = NULL;
+	uint32_t status;
+
+	status = amt_host_if_call(cmd,
+			(const unsigned char *)&CODE_VERSION_REQ,
+			sizeof(CODE_VERSION_REQ),
+			(uint8_t **)&response,
+			AMT_HOST_IF_CODE_VERSIONS_RESPONSE, 0);
+
+	if (status != AMT_STATUS_SUCCESS)
+		goto out;
+
+	status = amt_verify_code_versions(response);
+	if (status != AMT_STATUS_SUCCESS)
+		goto out;
+
+	memcpy(versions, response->data, sizeof(struct amt_code_versions));
+out:
+	if (response != NULL)
+		free(response);
+
+	return status;
+}
+
+/************************** end of amt_host_if_command ***********************/
+int main(int argc, char **argv)
+{
+	struct amt_code_versions ver;
+	struct amt_host_if acmd;
+	unsigned int i;
+	uint32_t status;
+	int ret;
+	bool verbose;
+
+	verbose = (argc > 1 && strcmp(argv[1], "-v") == 0);
+
+	if (!amt_host_if_init(&acmd, 5000, verbose)) {
+		ret = 1;
+		goto out;
+	}
+
+	status = amt_get_code_versions(&acmd, &ver);
+
+	amt_host_if_deinit(&acmd);
+
+	switch (status) {
+	case AMT_STATUS_HOST_IF_EMPTY_RESPONSE:
+		printf("Intel AMT: DISABLED\n");
+		ret = 0;
+		break;
+	case AMT_STATUS_SUCCESS:
+		printf("Intel AMT: ENABLED\n");
+		for (i = 0; i < ver.count; i++) {
+			printf("%s:\t%s\n", ver.versions[i].description.string,
+				ver.versions[i].version.string);
+		}
+		ret = 0;
+		break;
+	default:
+		printf("An error has occurred\n");
+		ret = 1;
+		break;
+	}
+
+out:
+	return ret;
+}

drivers/misc/mei/mei.h

@@ -0,0 +1,110 @@
+/******************************************************************************
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Intel MEI Interface Header
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ *	Intel Corporation.
+ *	linux-mei@linux.intel.com
+ *	http://www.intel.com
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2003 - 2012 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *****************************************************************************/
+
+#ifndef _LINUX_MEI_H
+#define _LINUX_MEI_H
+
+#include <linux/uuid.h>
+
+/*
+ * This IOCTL is used to associate the current file descriptor with a
+ * FW Client (given by UUID). This opens a communication channel
+ * between a host client and a FW client. From this point every read and write
+ * will communicate with the associated FW client.
+ * Only in close() (file_operation release()) the communication between
+ * the clients is disconnected
+ *
+ * The IOCTL argument is a struct with a union that contains
+ * the input parameter and the output parameter for this IOCTL.
+ *
+ * The input parameter is UUID of the FW Client.
+ * The output parameter is the properties of the FW client
+ * (FW protocol version and max message size).
+ *
+ */
+#define IOCTL_MEI_CONNECT_CLIENT \
+	_IOWR('H' , 0x01, struct mei_connect_client_data)
+
+/*
+ * Intel MEI client information struct
+ */
+struct mei_client {
+	__u32 max_msg_length;
+	__u8 protocol_version;
+	__u8 reserved[3];
+};
+
+/*
+ * IOCTL Connect Client Data structure
+ */
+struct mei_connect_client_data {
+	union {
+		uuid_le in_client_uuid;
+		struct mei_client out_client_properties;
+	};
+};
+
+#endif /* _LINUX_MEI_H  */

drivers/misc/mei/mei.txt

@@ -0,0 +1,215 @@
+Intel(R) Management Engine Interface (Intel(R) MEI)
+=======================
+
+Introduction
+=======================
+
+The Intel Management Engine (Intel ME) is an isolated and protected computing
+resource (Co-processor) residing inside certain Intel chipsets. The Intel ME
+provides support for computer/IT management features. The feature set
+depends on the Intel chipset SKU.
+
+The Intel Management Engine Interface (Intel MEI, previously known as HECI)
+is the interface between the Host and Intel ME. This interface is exposed
+to the host as a PCI device. The Intel MEI Driver is in charge of the
+communication channel between a host application and the Intel ME feature.
+
+Each Intel ME feature (Intel ME Client) is addressed by a GUID/UUID and
+each client has its own protocol. The protocol is message-based with a
+header and payload up to 512 bytes.
+
+Prominent usage of the Intel ME Interface is to communicate with Intel(R)
+Active Management Technology (Intel AMT)implemented in firmware running on
+the Intel ME.
+
+Intel AMT provides the ability to manage a host remotely out-of-band (OOB)
+even when the operating system running on the host processor has crashed or
+is in a sleep state.
+
+Some examples of Intel AMT usage are:
+   - Monitoring hardware state and platform components
+   - Remote power off/on (useful for green computing or overnight IT
+     maintenance)
+   - OS updates
+   - Storage of useful platform information such as software assets
+   - Built-in hardware KVM
+   - Selective network isolation of Ethernet and IP protocol flows based
+     on policies set by a remote management console
+   - IDE device redirection from remote management console
+
+Intel AMT (OOB) communication is based on SOAP (deprecated
+starting with Release 6.0) over HTTP/S or WS-Management protocol over
+HTTP/S that are received from a remote management console application.
+
+For more information about Intel AMT:
+http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide
+
+Intel MEI Driver
+=======================
+
+The driver exposes a misc device called /dev/mei.
+
+An application maintains communication with an Intel ME feature while
+/dev/mei is open. The binding to a specific features is performed by calling
+MEI_CONNECT_CLIENT_IOCTL, which passes the desired UUID.
+The number of instances of an Intel ME feature that can be opened
+at the same time depends on the Intel ME feature, but most of the
+features allow only a single instance.
+
+The Intel AMT Host Interface (Intel AMTHI) feature supports multiple
+simultaneous user applications. Therefore, the Intel MEI driver handles
+this internally by maintaining request queues for the applications.
+
+The driver is oblivious to data that is passed between firmware feature
+and host application.
+
+Because some of the Intel ME features can change the system
+configuration, the driver by default allows only a privileged
+user to access it.
+
+A code snippet for an application communicating with
+Intel AMTHI client:
+	struct mei_connect_client_data data;
+	fd = open(MEI_DEVICE);
+
+	data.d.in_client_uuid = AMTHI_UUID;
+
+	ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &data);
+
+	printf("Ver=%d, MaxLen=%ld\n",
+			data.d.in_client_uuid.protocol_version,
+			data.d.in_client_uuid.max_msg_length);
+
+	[...]
+
+	write(fd, amthi_req_data, amthi_req_data_len);
+
+	[...]
+
+	read(fd, &amthi_res_data, amthi_res_data_len);
+
+	[...]
+	close(fd);
+
+IOCTL:
+======
+The Intel MEI Driver supports the following IOCTL command:
+	IOCTL_MEI_CONNECT_CLIENT	Connect to firmware Feature (client).
+
+	usage:
+		struct mei_connect_client_data clientData;
+		ioctl(fd, IOCTL_MEI_CONNECT_CLIENT, &clientData);
+
+	inputs:
+		mei_connect_client_data struct contain the following
+		input field:
+
+		in_client_uuid -	UUID of the FW Feature that needs
+					to connect to.
+	outputs:
+		out_client_properties - Client Properties: MTU and Protocol Version.
+
+	error returns:
+		EINVAL	Wrong IOCTL Number
+		ENODEV	Device or Connection is not initialized or ready.
+			(e.g. Wrong UUID)
+		ENOMEM	Unable to allocate memory to client internal data.
+		EFAULT	Fatal Error (e.g. Unable to access user input data)
+		EBUSY	Connection Already Open
+
+	Notes:
+        max_msg_length (MTU) in client properties describes the maximum
+        data that can be sent or received. (e.g. if MTU=2K, can send
+        requests up to bytes 2k and received responses upto 2k bytes).
+
+Intel ME Applications:
+==============
+
+1) Intel Local Management Service (Intel LMS)
+
+	Applications running locally on the platform communicate with Intel AMT Release
+	2.0 and later releases in the same way that network applications do via SOAP
+	over HTTP (deprecated starting with Release 6.0) or with WS-Management over
+	SOAP over HTTP. This means that some Intel AMT features can be accessed from a
+	local application using the same network interface as a remote application
+	communicating with Intel AMT over the network.
+
+	When a local application sends a message addressed to the local Intel AMT host
+	name, the Intel LMS, which listens for traffic directed to the host name,
+	intercepts the message and routes it to the Intel MEI.
+	For more information:
+	http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide
+	Under "About Intel AMT" => "Local Access"
+
+	For downloading Intel LMS:
+	http://software.intel.com/en-us/articles/download-the-latest-intel-amt-open-source-drivers/
+
+	The Intel LMS opens a connection using the Intel MEI driver to the Intel LMS
+	firmware feature using a defined UUID and then communicates with the feature
+	using a protocol called Intel AMT Port Forwarding Protocol(Intel APF protocol).
+	The protocol is used to maintain multiple sessions with Intel AMT from a
+	single application.
+
+	See the protocol specification in the Intel AMT Software Development Kit(SDK)
+	http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide
+	Under "SDK Resources" => "Intel(R) vPro(TM) Gateway(MPS)"
+	=> "Information for Intel(R) vPro(TM) Gateway Developers"
+	=> "Description of the Intel AMT Port Forwarding (APF)Protocol"
+
+  2) Intel AMT Remote configuration using a Local Agent
+	A Local Agent enables IT personnel to configure Intel AMT out-of-the-box
+	without requiring installing additional data to enable setup. The remote
+	configuration process may involve an ISV-developed remote configuration
+	agent that runs on the host.
+	For more information:
+	http://software.intel.com/sites/manageability/AMT_Implementation_and_Reference_Guide
+	Under "Setup and Configuration of Intel AMT" =>
+	"SDK Tools Supporting Setup and Configuration" =>
+	"Using the Local Agent Sample"
+
+	An open source Intel AMT configuration utility,	implementing a local agent
+	that accesses the Intel MEI driver, can be found here:
+	http://software.intel.com/en-us/articles/download-the-latest-intel-amt-open-source-drivers/
+
+
+Intel AMT OS Health Watchdog:
+=============================
+The Intel AMT Watchdog is an OS Health (Hang/Crash) watchdog.
+Whenever the OS hangs or crashes, Intel AMT will send an event
+to any subscriber to this event. This mechanism means that
+IT knows when a platform crashes even when there is a hard failure on the host.
+
+The Intel AMT Watchdog is composed of two parts:
+	1) Firmware feature - receives the heartbeats
+	   and sends an event when the heartbeats stop.
+	2) Intel MEI driver - connects to the watchdog feature, configures the
+	   watchdog and sends the heartbeats.
+
+The Intel MEI driver uses the kernel watchdog to configure the Intel AMT
+Watchdog and to send heartbeats to it. The default timeout of the
+watchdog is 120 seconds.
+
+If the Intel AMT Watchdog feature does not exist (i.e. the connection failed),
+the Intel MEI driver will disable the sending of heartbeats.
+
+Supported Chipsets:
+==================
+7 Series Chipset Family
+6 Series Chipset Family
+5 Series Chipset Family
+4 Series Chipset Family
+Mobile 4 Series Chipset Family
+ICH9
+82946GZ/GL
+82G35 Express
+82Q963/Q965
+82P965/G965
+Mobile PM965/GM965
+Mobile GME965/GLE960
+82Q35 Express
+82G33/G31/P35/P31 Express
+82Q33 Express
+82X38/X48 Express
+
+---
+linux-mei@linux.intel.com

drivers/misc/mei/mei_dev.h

@@ -0,0 +1,428 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+
+#ifndef _MEI_DEV_H_
+#define _MEI_DEV_H_
+
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include "mei.h"
+#include "hw.h"
+
+/*
+ * watch dog definition
+ */
+#define MEI_WATCHDOG_DATA_SIZE         16
+#define MEI_START_WD_DATA_SIZE         20
+#define MEI_WD_PARAMS_SIZE             4
+#define MEI_WD_STATE_INDEPENDENCE_MSG_SENT       (1 << 0)
+
+#define MEI_RD_MSG_BUF_SIZE           (128 * sizeof(u32))
+
+/*
+ * MEI PCI Device object
+ */
+extern struct pci_dev *mei_device;
+
+
+/*
+ * AMTHI Client UUID
+ */
+extern const uuid_le mei_amthi_guid;
+
+/*
+ * Watchdog Client UUID
+ */
+extern const uuid_le mei_wd_guid;
+
+/*
+ * Watchdog independence state message
+ */
+extern const u8 mei_wd_state_independence_msg[3][4];
+
+/*
+ * Number of File descriptors/handles
+ * that can be opened to the driver.
+ *
+ * Limit to 253: 255 Total Clients
+ * minus internal client for AMTHI
+ * minus internal client for Watchdog
+ */
+#define  MEI_MAX_OPEN_HANDLE_COUNT	253
+
+/*
+ * Number of Maximum MEI Clients
+ */
+#define MEI_CLIENTS_MAX 255
+
+/* File state */
+enum file_state {
+	MEI_FILE_INITIALIZING = 0,
+	MEI_FILE_CONNECTING,
+	MEI_FILE_CONNECTED,
+	MEI_FILE_DISCONNECTING,
+	MEI_FILE_DISCONNECTED
+};
+
+/* MEI device states */
+enum mei_states {
+	MEI_INITIALIZING = 0,
+	MEI_INIT_CLIENTS,
+	MEI_ENABLED,
+	MEI_RESETING,
+	MEI_DISABLED,
+	MEI_RECOVERING_FROM_RESET,
+	MEI_POWER_DOWN,
+	MEI_POWER_UP
+};
+
+/* init clients states*/
+enum mei_init_clients_states {
+	MEI_START_MESSAGE = 0,
+	MEI_ENUM_CLIENTS_MESSAGE,
+	MEI_CLIENT_PROPERTIES_MESSAGE
+};
+
+enum iamthif_states {
+	MEI_IAMTHIF_IDLE,
+	MEI_IAMTHIF_WRITING,
+	MEI_IAMTHIF_FLOW_CONTROL,
+	MEI_IAMTHIF_READING,
+	MEI_IAMTHIF_READ_COMPLETE
+};
+
+enum mei_file_transaction_states {
+	MEI_IDLE,
+	MEI_WRITING,
+	MEI_WRITE_COMPLETE,
+	MEI_FLOW_CONTROL,
+	MEI_READING,
+	MEI_READ_COMPLETE
+};
+
+/* MEI CB */
+enum mei_cb_major_types {
+	MEI_READ = 0,
+	MEI_WRITE,
+	MEI_IOCTL,
+	MEI_OPEN,
+	MEI_CLOSE
+};
+
+/*
+ * Intel MEI message data struct
+ */
+struct mei_message_data {
+	u32 size;
+	unsigned char *data;
+} __packed;
+
+
+struct mei_cl_cb {
+	struct list_head cb_list;
+	enum mei_cb_major_types major_file_operations;
+	void *file_private;
+	struct mei_message_data request_buffer;
+	struct mei_message_data response_buffer;
+	unsigned long information;
+	unsigned long read_time;
+	struct file *file_object;
+};
+
+/* MEI client instance carried as file->pirvate_data*/
+struct mei_cl {
+	struct list_head link;
+	struct mei_device *dev;
+	enum file_state state;
+	wait_queue_head_t tx_wait;
+	wait_queue_head_t rx_wait;
+	wait_queue_head_t wait;
+	int read_pending;
+	int status;
+	/* ID of client connected */
+	u8 host_client_id;
+	u8 me_client_id;
+	u8 mei_flow_ctrl_creds;
+	u8 timer_count;
+	enum mei_file_transaction_states reading_state;
+	enum mei_file_transaction_states writing_state;
+	int sm_state;
+	struct mei_cl_cb *read_cb;
+};
+
+struct mei_io_list {
+	struct mei_cl_cb mei_cb;
+};
+
+/* MEI private device struct */
+struct mei_device {
+	struct pci_dev *pdev;	/* pointer to pci device struct */
+	/*
+	 * lists of queues
+	 */
+	 /* array of pointers to aio lists */
+	struct mei_io_list read_list;		/* driver read queue */
+	struct mei_io_list write_list;		/* driver write queue */
+	struct mei_io_list write_waiting_list;	/* write waiting queue */
+	struct mei_io_list ctrl_wr_list;	/* managed write IOCTL list */
+	struct mei_io_list ctrl_rd_list;	/* managed read IOCTL list */
+	struct mei_io_list amthi_cmd_list;	/* amthi list for cmd waiting */
+
+	/* driver managed amthi list for reading completed amthi cmd data */
+	struct mei_io_list amthi_read_complete_list;
+	/*
+	 * list of files
+	 */
+	struct list_head file_list;
+	long open_handle_count;
+	/*
+	 * memory of device
+	 */
+	unsigned int mem_base;
+	unsigned int mem_length;
+	void __iomem *mem_addr;
+	/*
+	 * lock for the device
+	 */
+	struct mutex device_lock; /* device lock */
+	struct delayed_work timer_work;	/* MEI timer delayed work (timeouts) */
+	bool recvd_msg;
+	/*
+	 * hw states of host and fw(ME)
+	 */
+	u32 host_hw_state;
+	u32 me_hw_state;
+	/*
+	 * waiting queue for receive message from FW
+	 */
+	wait_queue_head_t wait_recvd_msg;
+	wait_queue_head_t wait_stop_wd;
+
+	/*
+	 * mei device  states
+	 */
+	enum mei_states mei_state;
+	enum mei_init_clients_states init_clients_state;
+	u16 init_clients_timer;
+	bool stop;
+	bool need_reset;
+
+	u32 extra_write_index;
+	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];	/* control messages */
+	u32 wr_msg_buf[128];	/* used for control messages */
+	u32 ext_msg_buf[8];	/* for control responses */
+	u32 rd_msg_hdr;
+
+	struct hbm_version version;
+
+	struct mei_me_client *me_clients; /* Note: memory has to be allocated */
+	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
+	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
+	u8 me_clients_num;
+	u8 me_client_presentation_num;
+	u8 me_client_index;
+	bool mei_host_buffer_is_empty;
+
+	struct mei_cl wd_cl;
+	bool wd_pending;
+	bool wd_stopped;
+	bool wd_bypass;	/* if false, don't refresh watchdog ME client */
+	u16 wd_timeout;	/* seconds ((wd_data[1] << 8) + wd_data[0]) */
+	u16 wd_due_counter;
+	unsigned char wd_data[MEI_START_WD_DATA_SIZE];
+
+
+
+	struct file *iamthif_file_object;
+	struct mei_cl iamthif_cl;
+	struct mei_cl_cb *iamthif_current_cb;
+	int iamthif_mtu;
+	unsigned long iamthif_timer;
+	u32 iamthif_stall_timer;
+	unsigned char *iamthif_msg_buf; /* Note: memory has to be allocated */
+	u32 iamthif_msg_buf_size;
+	u32 iamthif_msg_buf_index;
+	enum iamthif_states iamthif_state;
+	bool iamthif_flow_control_pending;
+	bool iamthif_ioctl;
+	bool iamthif_canceled;
+
+	bool wd_interface_reg;
+};
+
+
+/*
+ * mei init function prototypes
+ */
+struct mei_device *mei_device_init(struct pci_dev *pdev);
+void mei_reset(struct mei_device *dev, int interrupts);
+int mei_hw_init(struct mei_device *dev);
+int mei_task_initialize_clients(void *data);
+int mei_initialize_clients(struct mei_device *dev);
+int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl);
+void mei_remove_client_from_file_list(struct mei_device *dev, u8 host_client_id);
+void mei_host_init_iamthif(struct mei_device *dev);
+void mei_allocate_me_clients_storage(struct mei_device *dev);
+
+
+u8 mei_find_me_client_update_filext(struct mei_device *dev,
+				struct mei_cl *priv,
+				const uuid_le *cguid, u8 client_id);
+
+/*
+ * MEI IO List Functions
+ */
+void mei_io_list_init(struct mei_io_list *list);
+void mei_io_list_flush(struct mei_io_list *list, struct mei_cl *cl);
+
+/*
+ * MEI ME Client Functions
+ */
+
+struct mei_cl *mei_cl_allocate(struct mei_device *dev);
+void mei_cl_init(struct mei_cl *cl, struct mei_device *dev);
+int mei_cl_flush_queues(struct mei_cl *cl);
+/**
+ * mei_cl_cmp_id - tells if file private data have same id
+ *
+ * @fe1: private data of 1. file object
+ * @fe2: private data of 2. file object
+ *
+ * returns true  - if ids are the same and not NULL
+ */
+static inline bool mei_cl_cmp_id(const struct mei_cl *cl1,
+				const struct mei_cl *cl2)
+{
+	return cl1 && cl2 &&
+		(cl1->host_client_id == cl2->host_client_id) &&
+		(cl1->me_client_id == cl2->me_client_id);
+}
+
+
+
+/*
+ * MEI Host Client Functions
+ */
+void mei_host_start_message(struct mei_device *dev);
+void mei_host_enum_clients_message(struct mei_device *dev);
+int mei_host_client_properties(struct mei_device *dev);
+
+/*
+ *  MEI interrupt functions prototype
+ */
+irqreturn_t mei_interrupt_quick_handler(int irq, void *dev_id);
+irqreturn_t mei_interrupt_thread_handler(int irq, void *dev_id);
+void mei_timer(struct work_struct *work);
+
+/*
+ *  MEI input output function prototype
+ */
+int mei_ioctl_connect_client(struct file *file,
+			struct mei_connect_client_data *data);
+
+int mei_start_read(struct mei_device *dev, struct mei_cl *cl);
+
+int amthi_write(struct mei_device *dev, struct mei_cl_cb *priv_cb);
+
+int amthi_read(struct mei_device *dev, struct file *file,
+	      char __user *ubuf, size_t length, loff_t *offset);
+
+struct mei_cl_cb *find_amthi_read_list_entry(struct mei_device *dev,
+						struct file *file);
+
+void mei_run_next_iamthif_cmd(struct mei_device *dev);
+
+void mei_free_cb_private(struct mei_cl_cb *priv_cb);
+
+int mei_find_me_client_index(const struct mei_device *dev, uuid_le cuuid);
+
+/*
+ * Register Access Function
+ */
+
+/**
+ * mei_reg_read - Reads 32bit data from the mei device
+ *
+ * @dev: the device structure
+ * @offset: offset from which to read the data
+ *
+ * returns register value (u32)
+ */
+static inline u32 mei_reg_read(struct mei_device *dev, unsigned long offset)
+{
+	return ioread32(dev->mem_addr + offset);
+}
+
+/**
+ * mei_reg_write - Writes 32bit data to the mei device
+ *
+ * @dev: the device structure
+ * @offset: offset from which to write the data
+ * @value: register value to write (u32)
+ */
+static inline void mei_reg_write(struct mei_device *dev,
+				unsigned long offset, u32 value)
+{
+	iowrite32(value, dev->mem_addr + offset);
+}
+
+/**
+ * mei_hcsr_read - Reads 32bit data from the host CSR
+ *
+ * @dev: the device structure
+ *
+ * returns the byte read.
+ */
+static inline u32 mei_hcsr_read(struct mei_device *dev)
+{
+	return mei_reg_read(dev, H_CSR);
+}
+
+/**
+ * mei_mecsr_read - Reads 32bit data from the ME CSR
+ *
+ * @dev: the device structure
+ *
+ * returns ME_CSR_HA register value (u32)
+ */
+static inline u32 mei_mecsr_read(struct mei_device *dev)
+{
+	return mei_reg_read(dev, ME_CSR_HA);
+}
+
+/**
+ * get_me_cb_rw - Reads 32bit data from the mei ME_CB_RW register
+ *
+ * @dev: the device structure
+ *
+ * returns ME_CB_RW register value (u32)
+ */
+static inline u32 mei_mecbrw_read(struct mei_device *dev)
+{
+	return mei_reg_read(dev, ME_CB_RW);
+}
+
+
+/*
+ * mei interface function prototypes
+ */
+void mei_hcsr_set(struct mei_device *dev);
+void mei_csr_clear_his(struct mei_device *dev);
+
+void mei_enable_interrupts(struct mei_device *dev);
+void mei_disable_interrupts(struct mei_device *dev);
+
+#endif

drivers/misc/mei/wd.c

@@ -0,0 +1,379 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2012, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/watchdog.h>
+
+#include "mei_dev.h"
+#include "hw.h"
+#include "interface.h"
+#include "mei.h"
+
+static const u8 mei_start_wd_params[] = { 0x02, 0x12, 0x13, 0x10 };
+static const u8 mei_stop_wd_params[] = { 0x02, 0x02, 0x14, 0x10 };
+
+const u8 mei_wd_state_independence_msg[3][4] = {
+	{0x05, 0x02, 0x51, 0x10},
+	{0x05, 0x02, 0x52, 0x10},
+	{0x07, 0x02, 0x01, 0x10}
+};
+
+/*
+ * AMT Watchdog Device
+ */
+#define INTEL_AMT_WATCHDOG_ID "INTCAMT"
+
+/* UUIDs for AMT F/W clients */
+const uuid_le mei_wd_guid = UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
+						0x9D, 0xA9, 0x15, 0x14, 0xCB,
+						0x32, 0xAB);
+
+static void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout)
+{
+	dev_dbg(&dev->pdev->dev, "wd: set timeout=%d.\n", timeout);
+	memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE);
+	memcpy(dev->wd_data + MEI_WD_PARAMS_SIZE, &timeout, sizeof(u16));
+}
+
+/**
+ * host_init_wd - mei initialization wd.
+ *
+ * @dev: the device structure
+ * returns -ENENT if wd client cannot be found
+ *         -EIO if write has failed
+ */
+int mei_wd_host_init(struct mei_device *dev)
+{
+	mei_cl_init(&dev->wd_cl, dev);
+
+	/* look for WD client and connect to it */
+	dev->wd_cl.state = MEI_FILE_DISCONNECTED;
+	dev->wd_timeout = AMT_WD_DEFAULT_TIMEOUT;
+
+	/* find ME WD client */
+	mei_find_me_client_update_filext(dev, &dev->wd_cl,
+				&mei_wd_guid, MEI_WD_HOST_CLIENT_ID);
+
+	dev_dbg(&dev->pdev->dev, "wd: check client\n");
+	if (MEI_FILE_CONNECTING != dev->wd_cl.state) {
+		dev_info(&dev->pdev->dev, "wd: failed to find the client\n");
+		return -ENOENT;
+	}
+
+	if (mei_connect(dev, &dev->wd_cl)) {
+		dev_err(&dev->pdev->dev, "wd: failed to connect to the client\n");
+		dev->wd_cl.state = MEI_FILE_DISCONNECTED;
+		dev->wd_cl.host_client_id = 0;
+		return -EIO;
+	}
+	dev->wd_cl.timer_count = CONNECT_TIMEOUT;
+
+	return 0;
+}
+
+/**
+ * mei_wd_send - sends watch dog message to fw.
+ *
+ * @dev: the device structure
+ *
+ * returns 0 if success,
+ *	-EIO when message send fails
+ *	-EINVAL when invalid message is to be sent
+ */
+int mei_wd_send(struct mei_device *dev)
+{
+	struct mei_msg_hdr *mei_hdr;
+
+	mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
+	mei_hdr->host_addr = dev->wd_cl.host_client_id;
+	mei_hdr->me_addr = dev->wd_cl.me_client_id;
+	mei_hdr->msg_complete = 1;
+	mei_hdr->reserved = 0;
+
+	if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE))
+		mei_hdr->length = MEI_START_WD_DATA_SIZE;
+	else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE))
+		mei_hdr->length = MEI_WD_PARAMS_SIZE;
+	else
+		return -EINVAL;
+
+	return mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length);
+}
+
+/**
+ * mei_wd_stop - sends watchdog stop message to fw.
+ *
+ * @dev: the device structure
+ * @preserve: indicate if to keep the timeout value
+ *
+ * returns 0 if success,
+ *	-EIO when message send fails
+ *	-EINVAL when invalid message is to be sent
+ */
+int mei_wd_stop(struct mei_device *dev, bool preserve)
+{
+	int ret;
+	u16 wd_timeout = dev->wd_timeout;
+
+	cancel_delayed_work(&dev->timer_work);
+	if (dev->wd_cl.state != MEI_FILE_CONNECTED || !dev->wd_timeout)
+		return 0;
+
+	dev->wd_timeout = 0;
+	dev->wd_due_counter = 0;
+	memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE);
+	dev->stop = true;
+
+	ret = mei_flow_ctrl_creds(dev, &dev->wd_cl);
+	if (ret < 0)
+		goto out;
+
+	if (ret && dev->mei_host_buffer_is_empty) {
+		ret = 0;
+		dev->mei_host_buffer_is_empty = false;
+
+		if (!mei_wd_send(dev)) {
+			ret = mei_flow_ctrl_reduce(dev, &dev->wd_cl);
+			if (ret)
+				goto out;
+		} else {
+			dev_err(&dev->pdev->dev, "wd: send stop failed\n");
+		}
+
+		dev->wd_pending = false;
+	} else {
+		dev->wd_pending = true;
+	}
+	dev->wd_stopped = false;
+	mutex_unlock(&dev->device_lock);
+
+	ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
+					dev->wd_stopped, 10 * HZ);
+	mutex_lock(&dev->device_lock);
+	if (dev->wd_stopped) {
+		dev_dbg(&dev->pdev->dev, "wd: stop completed ret=%d.\n", ret);
+		ret = 0;
+	} else {
+		if (!ret)
+			ret = -ETIMEDOUT;
+		dev_warn(&dev->pdev->dev,
+			"wd: stop failed to complete ret=%d.\n", ret);
+	}
+
+	if (preserve)
+		dev->wd_timeout = wd_timeout;
+
+out:
+	return ret;
+}
+
+/*
+ * mei_wd_ops_start - wd start command from the watchdog core.
+ *
+ * @wd_dev - watchdog device struct
+ *
+ * returns 0 if success, negative errno code for failure
+ */
+static int mei_wd_ops_start(struct watchdog_device *wd_dev)
+{
+	int err = -ENODEV;
+	struct mei_device *dev;
+
+	dev = pci_get_drvdata(mei_device);
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (dev->mei_state != MEI_ENABLED) {
+		dev_dbg(&dev->pdev->dev,
+			"wd: mei_state != MEI_ENABLED  mei_state = %d\n",
+			dev->mei_state);
+		goto end_unlock;
+	}
+
+	if (dev->wd_cl.state != MEI_FILE_CONNECTED)	{
+		dev_dbg(&dev->pdev->dev,
+			"MEI Driver is not connected to Watchdog Client\n");
+		goto end_unlock;
+	}
+
+	mei_wd_set_start_timeout(dev, dev->wd_timeout);
+
+	err = 0;
+end_unlock:
+	mutex_unlock(&dev->device_lock);
+	return err;
+}
+
+/*
+ * mei_wd_ops_stop -  wd stop command from the watchdog core.
+ *
+ * @wd_dev - watchdog device struct
+ *
+ * returns 0 if success, negative errno code for failure
+ */
+static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
+{
+	struct mei_device *dev;
+	dev = pci_get_drvdata(mei_device);
+
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+	mei_wd_stop(dev, false);
+	mutex_unlock(&dev->device_lock);
+
+	return 0;
+}
+
+/*
+ * mei_wd_ops_ping - wd ping command from the watchdog core.
+ *
+ * @wd_dev - watchdog device struct
+ *
+ * returns 0 if success, negative errno code for failure
+ */
+static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
+{
+	int ret = 0;
+	struct mei_device *dev;
+	dev = pci_get_drvdata(mei_device);
+
+	if (!dev)
+		return -ENODEV;
+
+	mutex_lock(&dev->device_lock);
+
+	if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
+		dev_err(&dev->pdev->dev, "wd: not connected.\n");
+		ret = -ENODEV;
+		goto end;
+	}
+
+	/* Check if we can send the ping to HW*/
+	if (dev->mei_host_buffer_is_empty &&
+		mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) {
+
+		dev->mei_host_buffer_is_empty = false;
+		dev_dbg(&dev->pdev->dev, "wd: sending ping\n");
+
+		if (mei_wd_send(dev)) {
+			dev_err(&dev->pdev->dev, "wd: send failed.\n");
+			ret = -EIO;
+			goto end;
+		}
+
+		if (mei_flow_ctrl_reduce(dev, &dev->wd_cl)) {
+			dev_err(&dev->pdev->dev,
+				"wd: mei_flow_ctrl_reduce() failed.\n");
+			ret = -EIO;
+			goto end;
+		}
+
+	} else {
+		dev->wd_pending = true;
+	}
+
+end:
+	mutex_unlock(&dev->device_lock);
+	return ret;
+}
+
+/*
+ * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
+ *
+ * @wd_dev - watchdog device struct
+ * @timeout - timeout value to set
+ *
+ * returns 0 if success, negative errno code for failure
+ */
+static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev, unsigned int timeout)
+{
+	struct mei_device *dev;
+	dev = pci_get_drvdata(mei_device);
+
+	if (!dev)
+		return -ENODEV;
+
+	/* Check Timeout value */
+	if (timeout < AMT_WD_MIN_TIMEOUT || timeout > AMT_WD_MAX_TIMEOUT)
+		return -EINVAL;
+
+	mutex_lock(&dev->device_lock);
+
+	dev->wd_timeout = timeout;
+	wd_dev->timeout = timeout;
+	mei_wd_set_start_timeout(dev, dev->wd_timeout);
+
+	mutex_unlock(&dev->device_lock);
+
+	return 0;
+}
+
+/*
+ * Watchdog Device structs
+ */
+static const struct watchdog_ops wd_ops = {
+		.owner = THIS_MODULE,
+		.start = mei_wd_ops_start,
+		.stop = mei_wd_ops_stop,
+		.ping = mei_wd_ops_ping,
+		.set_timeout = mei_wd_ops_set_timeout,
+};
+static const struct watchdog_info wd_info = {
+		.identity = INTEL_AMT_WATCHDOG_ID,
+		.options = WDIOF_KEEPALIVEPING,
+};
+
+static struct watchdog_device amt_wd_dev = {
+		.info = &wd_info,
+		.ops = &wd_ops,
+		.timeout = AMT_WD_DEFAULT_TIMEOUT,
+		.min_timeout = AMT_WD_MIN_TIMEOUT,
+		.max_timeout = AMT_WD_MAX_TIMEOUT,
+};
+
+
+void  mei_watchdog_register(struct mei_device *dev)
+{
+	dev_dbg(&dev->pdev->dev, "dev->wd_timeout =%d.\n", dev->wd_timeout);
+
+	dev->wd_due_counter = !!dev->wd_timeout;
+
+	if (watchdog_register_device(&amt_wd_dev)) {
+		dev_err(&dev->pdev->dev,
+			"wd: unable to register watchdog device.\n");
+		dev->wd_interface_reg = false;
+	} else {
+		dev_dbg(&dev->pdev->dev,
+			"wd: successfully register watchdog interface.\n");
+		dev->wd_interface_reg = true;
+	}
+}
+
+void mei_watchdog_unregister(struct mei_device *dev)
+{
+	if (dev->wd_interface_reg)
+		watchdog_unregister_device(&amt_wd_dev);
+	dev->wd_interface_reg = false;
+}
+