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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * MCP2221A - Microchip USB to I2C Host Protocol Bridge
- *
- * Copyright (c) 2020, Rishi Gupta <[email protected]>
- *
- * Datasheet: https://ww1.microchip.com/downloads/en/DeviceDoc/20005565B.pdf
- */
- #include <linux/module.h>
- #include <linux/err.h>
- #include <linux/mutex.h>
- #include <linux/completion.h>
- #include <linux/delay.h>
- #include <linux/hid.h>
- #include <linux/hidraw.h>
- #include <linux/i2c.h>
- #include <linux/gpio/driver.h>
- #include "hid-ids.h"
- /* Commands codes in a raw output report */
- enum {
- MCP2221_I2C_WR_DATA = 0x90,
- MCP2221_I2C_WR_NO_STOP = 0x94,
- MCP2221_I2C_RD_DATA = 0x91,
- MCP2221_I2C_RD_RPT_START = 0x93,
- MCP2221_I2C_GET_DATA = 0x40,
- MCP2221_I2C_PARAM_OR_STATUS = 0x10,
- MCP2221_I2C_SET_SPEED = 0x20,
- MCP2221_I2C_CANCEL = 0x10,
- MCP2221_GPIO_SET = 0x50,
- MCP2221_GPIO_GET = 0x51,
- };
- /* Response codes in a raw input report */
- enum {
- MCP2221_SUCCESS = 0x00,
- MCP2221_I2C_ENG_BUSY = 0x01,
- MCP2221_I2C_START_TOUT = 0x12,
- MCP2221_I2C_STOP_TOUT = 0x62,
- MCP2221_I2C_WRADDRL_TOUT = 0x23,
- MCP2221_I2C_WRDATA_TOUT = 0x44,
- MCP2221_I2C_WRADDRL_NACK = 0x25,
- MCP2221_I2C_MASK_ADDR_NACK = 0x40,
- MCP2221_I2C_WRADDRL_SEND = 0x21,
- MCP2221_I2C_ADDR_NACK = 0x25,
- MCP2221_I2C_READ_COMPL = 0x55,
- MCP2221_ALT_F_NOT_GPIOV = 0xEE,
- MCP2221_ALT_F_NOT_GPIOD = 0xEF,
- };
- /* MCP GPIO direction encoding */
- enum {
- MCP2221_DIR_OUT = 0x00,
- MCP2221_DIR_IN = 0x01,
- };
- #define MCP_NGPIO 4
- /* MCP GPIO set command layout */
- struct mcp_set_gpio {
- u8 cmd;
- u8 dummy;
- struct {
- u8 change_value;
- u8 value;
- u8 change_direction;
- u8 direction;
- } gpio[MCP_NGPIO];
- } __packed;
- /* MCP GPIO get command layout */
- struct mcp_get_gpio {
- u8 cmd;
- u8 dummy;
- struct {
- u8 direction;
- u8 value;
- } gpio[MCP_NGPIO];
- } __packed;
- /*
- * There is no way to distinguish responses. Therefore next command
- * is sent only after response to previous has been received. Mutex
- * lock is used for this purpose mainly.
- */
- struct mcp2221 {
- struct hid_device *hdev;
- struct i2c_adapter adapter;
- struct mutex lock;
- struct completion wait_in_report;
- u8 *rxbuf;
- u8 txbuf[64];
- int rxbuf_idx;
- int status;
- u8 cur_i2c_clk_div;
- struct gpio_chip *gc;
- u8 gp_idx;
- u8 gpio_dir;
- };
- /*
- * Default i2c bus clock frequency 400 kHz. Modify this if you
- * want to set some other frequency (min 50 kHz - max 400 kHz).
- */
- static uint i2c_clk_freq = 400;
- /* Synchronously send output report to the device */
- static int mcp_send_report(struct mcp2221 *mcp,
- u8 *out_report, size_t len)
- {
- u8 *buf;
- int ret;
- buf = kmemdup(out_report, len, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- /* mcp2221 uses interrupt endpoint for out reports */
- ret = hid_hw_output_report(mcp->hdev, buf, len);
- kfree(buf);
- if (ret < 0)
- return ret;
- return 0;
- }
- /*
- * Send o/p report to the device and wait for i/p report to be
- * received from the device. If the device does not respond,
- * we timeout.
- */
- static int mcp_send_data_req_status(struct mcp2221 *mcp,
- u8 *out_report, int len)
- {
- int ret;
- unsigned long t;
- reinit_completion(&mcp->wait_in_report);
- ret = mcp_send_report(mcp, out_report, len);
- if (ret)
- return ret;
- t = wait_for_completion_timeout(&mcp->wait_in_report,
- msecs_to_jiffies(4000));
- if (!t)
- return -ETIMEDOUT;
- return mcp->status;
- }
- /* Check pass/fail for actual communication with i2c slave */
- static int mcp_chk_last_cmd_status(struct mcp2221 *mcp)
- {
- memset(mcp->txbuf, 0, 8);
- mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
- return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
- }
- /* Cancels last command releasing i2c bus just in case occupied */
- static int mcp_cancel_last_cmd(struct mcp2221 *mcp)
- {
- memset(mcp->txbuf, 0, 8);
- mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
- mcp->txbuf[2] = MCP2221_I2C_CANCEL;
- return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
- }
- static int mcp_set_i2c_speed(struct mcp2221 *mcp)
- {
- int ret;
- memset(mcp->txbuf, 0, 8);
- mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
- mcp->txbuf[3] = MCP2221_I2C_SET_SPEED;
- mcp->txbuf[4] = mcp->cur_i2c_clk_div;
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 8);
- if (ret) {
- /* Small delay is needed here */
- usleep_range(980, 1000);
- mcp_cancel_last_cmd(mcp);
- }
- return 0;
- }
- /*
- * An output report can contain minimum 1 and maximum 60 user data
- * bytes. If the number of data bytes is more then 60, we send it
- * in chunks of 60 bytes. Last chunk may contain exactly 60 or less
- * bytes. Total number of bytes is informed in very first report to
- * mcp2221, from that point onwards it first collect all the data
- * from host and then send to i2c slave device.
- */
- static int mcp_i2c_write(struct mcp2221 *mcp,
- struct i2c_msg *msg, int type, u8 last_status)
- {
- int ret, len, idx, sent;
- idx = 0;
- sent = 0;
- if (msg->len < 60)
- len = msg->len;
- else
- len = 60;
- do {
- mcp->txbuf[0] = type;
- mcp->txbuf[1] = msg->len & 0xff;
- mcp->txbuf[2] = msg->len >> 8;
- mcp->txbuf[3] = (u8)(msg->addr << 1);
- memcpy(&mcp->txbuf[4], &msg->buf[idx], len);
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, len + 4);
- if (ret)
- return ret;
- usleep_range(980, 1000);
- if (last_status) {
- ret = mcp_chk_last_cmd_status(mcp);
- if (ret)
- return ret;
- }
- sent = sent + len;
- if (sent >= msg->len)
- break;
- idx = idx + len;
- if ((msg->len - sent) < 60)
- len = msg->len - sent;
- else
- len = 60;
- /*
- * Testing shows delay is needed between successive writes
- * otherwise next write fails on first-try from i2c core.
- * This value is obtained through automated stress testing.
- */
- usleep_range(980, 1000);
- } while (len > 0);
- return ret;
- }
- /*
- * Device reads all data (0 - 65535 bytes) from i2c slave device and
- * stores it in device itself. This data is read back from device to
- * host in multiples of 60 bytes using input reports.
- */
- static int mcp_i2c_smbus_read(struct mcp2221 *mcp,
- struct i2c_msg *msg, int type, u16 smbus_addr,
- u8 smbus_len, u8 *smbus_buf)
- {
- int ret;
- u16 total_len;
- mcp->txbuf[0] = type;
- if (msg) {
- mcp->txbuf[1] = msg->len & 0xff;
- mcp->txbuf[2] = msg->len >> 8;
- mcp->txbuf[3] = (u8)(msg->addr << 1);
- total_len = msg->len;
- mcp->rxbuf = msg->buf;
- } else {
- mcp->txbuf[1] = smbus_len;
- mcp->txbuf[2] = 0;
- mcp->txbuf[3] = (u8)(smbus_addr << 1);
- total_len = smbus_len;
- mcp->rxbuf = smbus_buf;
- }
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 4);
- if (ret)
- return ret;
- mcp->rxbuf_idx = 0;
- do {
- memset(mcp->txbuf, 0, 4);
- mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
- if (ret)
- return ret;
- ret = mcp_chk_last_cmd_status(mcp);
- if (ret)
- return ret;
- usleep_range(980, 1000);
- } while (mcp->rxbuf_idx < total_len);
- return ret;
- }
- static int mcp_i2c_xfer(struct i2c_adapter *adapter,
- struct i2c_msg msgs[], int num)
- {
- int ret;
- struct mcp2221 *mcp = i2c_get_adapdata(adapter);
- hid_hw_power(mcp->hdev, PM_HINT_FULLON);
- mutex_lock(&mcp->lock);
- /* Setting speed before every transaction is required for mcp2221 */
- ret = mcp_set_i2c_speed(mcp);
- if (ret)
- goto exit;
- if (num == 1) {
- if (msgs->flags & I2C_M_RD) {
- ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA,
- 0, 0, NULL);
- } else {
- ret = mcp_i2c_write(mcp, msgs, MCP2221_I2C_WR_DATA, 1);
- }
- if (ret)
- goto exit;
- ret = num;
- } else if (num == 2) {
- /* Ex transaction; send reg address and read its contents */
- if (msgs[0].addr == msgs[1].addr &&
- !(msgs[0].flags & I2C_M_RD) &&
- (msgs[1].flags & I2C_M_RD)) {
- ret = mcp_i2c_write(mcp, &msgs[0],
- MCP2221_I2C_WR_NO_STOP, 0);
- if (ret)
- goto exit;
- ret = mcp_i2c_smbus_read(mcp, &msgs[1],
- MCP2221_I2C_RD_RPT_START,
- 0, 0, NULL);
- if (ret)
- goto exit;
- ret = num;
- } else {
- dev_err(&adapter->dev,
- "unsupported multi-msg i2c transaction\n");
- ret = -EOPNOTSUPP;
- }
- } else {
- dev_err(&adapter->dev,
- "unsupported multi-msg i2c transaction\n");
- ret = -EOPNOTSUPP;
- }
- exit:
- hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
- mutex_unlock(&mcp->lock);
- return ret;
- }
- static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr,
- u8 command, u8 *buf, u8 len, int type,
- u8 last_status)
- {
- int data_len, ret;
- mcp->txbuf[0] = type;
- mcp->txbuf[1] = len + 1; /* 1 is due to command byte itself */
- mcp->txbuf[2] = 0;
- mcp->txbuf[3] = (u8)(addr << 1);
- mcp->txbuf[4] = command;
- switch (len) {
- case 0:
- data_len = 5;
- break;
- case 1:
- mcp->txbuf[5] = buf[0];
- data_len = 6;
- break;
- case 2:
- mcp->txbuf[5] = buf[0];
- mcp->txbuf[6] = buf[1];
- data_len = 7;
- break;
- default:
- if (len > I2C_SMBUS_BLOCK_MAX)
- return -EINVAL;
- memcpy(&mcp->txbuf[5], buf, len);
- data_len = len + 5;
- }
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, data_len);
- if (ret)
- return ret;
- if (last_status) {
- usleep_range(980, 1000);
- ret = mcp_chk_last_cmd_status(mcp);
- if (ret)
- return ret;
- }
- return ret;
- }
- static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
- unsigned short flags, char read_write,
- u8 command, int size,
- union i2c_smbus_data *data)
- {
- int ret;
- struct mcp2221 *mcp = i2c_get_adapdata(adapter);
- hid_hw_power(mcp->hdev, PM_HINT_FULLON);
- mutex_lock(&mcp->lock);
- ret = mcp_set_i2c_speed(mcp);
- if (ret)
- goto exit;
- switch (size) {
- case I2C_SMBUS_QUICK:
- if (read_write == I2C_SMBUS_READ)
- ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
- addr, 0, &data->byte);
- else
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_DATA, 1);
- break;
- case I2C_SMBUS_BYTE:
- if (read_write == I2C_SMBUS_READ)
- ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
- addr, 1, &data->byte);
- else
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_DATA, 1);
- break;
- case I2C_SMBUS_BYTE_DATA:
- if (read_write == I2C_SMBUS_READ) {
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_NO_STOP, 0);
- if (ret)
- goto exit;
- ret = mcp_i2c_smbus_read(mcp, NULL,
- MCP2221_I2C_RD_RPT_START,
- addr, 1, &data->byte);
- } else {
- ret = mcp_smbus_write(mcp, addr, command, &data->byte,
- 1, MCP2221_I2C_WR_DATA, 1);
- }
- break;
- case I2C_SMBUS_WORD_DATA:
- if (read_write == I2C_SMBUS_READ) {
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_NO_STOP, 0);
- if (ret)
- goto exit;
- ret = mcp_i2c_smbus_read(mcp, NULL,
- MCP2221_I2C_RD_RPT_START,
- addr, 2, (u8 *)&data->word);
- } else {
- ret = mcp_smbus_write(mcp, addr, command,
- (u8 *)&data->word, 2,
- MCP2221_I2C_WR_DATA, 1);
- }
- break;
- case I2C_SMBUS_BLOCK_DATA:
- if (read_write == I2C_SMBUS_READ) {
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_NO_STOP, 1);
- if (ret)
- goto exit;
- mcp->rxbuf_idx = 0;
- mcp->rxbuf = data->block;
- mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
- if (ret)
- goto exit;
- } else {
- if (!data->block[0]) {
- ret = -EINVAL;
- goto exit;
- }
- ret = mcp_smbus_write(mcp, addr, command, data->block,
- data->block[0] + 1,
- MCP2221_I2C_WR_DATA, 1);
- }
- break;
- case I2C_SMBUS_I2C_BLOCK_DATA:
- if (read_write == I2C_SMBUS_READ) {
- ret = mcp_smbus_write(mcp, addr, command, NULL,
- 0, MCP2221_I2C_WR_NO_STOP, 1);
- if (ret)
- goto exit;
- mcp->rxbuf_idx = 0;
- mcp->rxbuf = data->block;
- mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
- if (ret)
- goto exit;
- } else {
- if (!data->block[0]) {
- ret = -EINVAL;
- goto exit;
- }
- ret = mcp_smbus_write(mcp, addr, command,
- &data->block[1], data->block[0],
- MCP2221_I2C_WR_DATA, 1);
- }
- break;
- case I2C_SMBUS_PROC_CALL:
- ret = mcp_smbus_write(mcp, addr, command,
- (u8 *)&data->word,
- 2, MCP2221_I2C_WR_NO_STOP, 0);
- if (ret)
- goto exit;
- ret = mcp_i2c_smbus_read(mcp, NULL,
- MCP2221_I2C_RD_RPT_START,
- addr, 2, (u8 *)&data->word);
- break;
- case I2C_SMBUS_BLOCK_PROC_CALL:
- ret = mcp_smbus_write(mcp, addr, command, data->block,
- data->block[0] + 1,
- MCP2221_I2C_WR_NO_STOP, 0);
- if (ret)
- goto exit;
- ret = mcp_i2c_smbus_read(mcp, NULL,
- MCP2221_I2C_RD_RPT_START,
- addr, I2C_SMBUS_BLOCK_MAX,
- data->block);
- break;
- default:
- dev_err(&mcp->adapter.dev,
- "unsupported smbus transaction size:%d\n", size);
- ret = -EOPNOTSUPP;
- }
- exit:
- hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
- mutex_unlock(&mcp->lock);
- return ret;
- }
- static u32 mcp_i2c_func(struct i2c_adapter *adapter)
- {
- return I2C_FUNC_I2C |
- I2C_FUNC_SMBUS_READ_BLOCK_DATA |
- I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
- (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_PEC);
- }
- static const struct i2c_algorithm mcp_i2c_algo = {
- .master_xfer = mcp_i2c_xfer,
- .smbus_xfer = mcp_smbus_xfer,
- .functionality = mcp_i2c_func,
- };
- static int mcp_gpio_get(struct gpio_chip *gc,
- unsigned int offset)
- {
- int ret;
- struct mcp2221 *mcp = gpiochip_get_data(gc);
- mcp->txbuf[0] = MCP2221_GPIO_GET;
- mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset].value);
- mutex_lock(&mcp->lock);
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
- mutex_unlock(&mcp->lock);
- return ret;
- }
- static void mcp_gpio_set(struct gpio_chip *gc,
- unsigned int offset, int value)
- {
- struct mcp2221 *mcp = gpiochip_get_data(gc);
- memset(mcp->txbuf, 0, 18);
- mcp->txbuf[0] = MCP2221_GPIO_SET;
- mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].value);
- mcp->txbuf[mcp->gp_idx - 1] = 1;
- mcp->txbuf[mcp->gp_idx] = !!value;
- mutex_lock(&mcp->lock);
- mcp_send_data_req_status(mcp, mcp->txbuf, 18);
- mutex_unlock(&mcp->lock);
- }
- static int mcp_gpio_dir_set(struct mcp2221 *mcp,
- unsigned int offset, u8 val)
- {
- memset(mcp->txbuf, 0, 18);
- mcp->txbuf[0] = MCP2221_GPIO_SET;
- mcp->gp_idx = offsetof(struct mcp_set_gpio, gpio[offset].direction);
- mcp->txbuf[mcp->gp_idx - 1] = 1;
- mcp->txbuf[mcp->gp_idx] = val;
- return mcp_send_data_req_status(mcp, mcp->txbuf, 18);
- }
- static int mcp_gpio_direction_input(struct gpio_chip *gc,
- unsigned int offset)
- {
- int ret;
- struct mcp2221 *mcp = gpiochip_get_data(gc);
- mutex_lock(&mcp->lock);
- ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_IN);
- mutex_unlock(&mcp->lock);
- return ret;
- }
- static int mcp_gpio_direction_output(struct gpio_chip *gc,
- unsigned int offset, int value)
- {
- int ret;
- struct mcp2221 *mcp = gpiochip_get_data(gc);
- mutex_lock(&mcp->lock);
- ret = mcp_gpio_dir_set(mcp, offset, MCP2221_DIR_OUT);
- mutex_unlock(&mcp->lock);
- /* Can't configure as output, bailout early */
- if (ret)
- return ret;
- mcp_gpio_set(gc, offset, value);
- return 0;
- }
- static int mcp_gpio_get_direction(struct gpio_chip *gc,
- unsigned int offset)
- {
- int ret;
- struct mcp2221 *mcp = gpiochip_get_data(gc);
- mcp->txbuf[0] = MCP2221_GPIO_GET;
- mcp->gp_idx = offsetof(struct mcp_get_gpio, gpio[offset].direction);
- mutex_lock(&mcp->lock);
- ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
- mutex_unlock(&mcp->lock);
- if (ret)
- return ret;
- if (mcp->gpio_dir == MCP2221_DIR_IN)
- return GPIO_LINE_DIRECTION_IN;
- return GPIO_LINE_DIRECTION_OUT;
- }
- /* Gives current state of i2c engine inside mcp2221 */
- static int mcp_get_i2c_eng_state(struct mcp2221 *mcp,
- u8 *data, u8 idx)
- {
- int ret;
- switch (data[idx]) {
- case MCP2221_I2C_WRADDRL_NACK:
- case MCP2221_I2C_WRADDRL_SEND:
- ret = -ENXIO;
- break;
- case MCP2221_I2C_START_TOUT:
- case MCP2221_I2C_STOP_TOUT:
- case MCP2221_I2C_WRADDRL_TOUT:
- case MCP2221_I2C_WRDATA_TOUT:
- ret = -ETIMEDOUT;
- break;
- case MCP2221_I2C_ENG_BUSY:
- ret = -EAGAIN;
- break;
- case MCP2221_SUCCESS:
- ret = 0x00;
- break;
- default:
- ret = -EIO;
- }
- return ret;
- }
- /*
- * MCP2221 uses interrupt endpoint for input reports. This function
- * is called by HID layer when it receives i/p report from mcp2221,
- * which is actually a response to the previously sent command.
- *
- * MCP2221A firmware specific return codes are parsed and 0 or
- * appropriate negative error code is returned. Delayed response
- * results in timeout error and stray reponses results in -EIO.
- */
- static int mcp2221_raw_event(struct hid_device *hdev,
- struct hid_report *report, u8 *data, int size)
- {
- u8 *buf;
- struct mcp2221 *mcp = hid_get_drvdata(hdev);
- switch (data[0]) {
- case MCP2221_I2C_WR_DATA:
- case MCP2221_I2C_WR_NO_STOP:
- case MCP2221_I2C_RD_DATA:
- case MCP2221_I2C_RD_RPT_START:
- switch (data[1]) {
- case MCP2221_SUCCESS:
- mcp->status = 0;
- break;
- default:
- mcp->status = mcp_get_i2c_eng_state(mcp, data, 2);
- }
- complete(&mcp->wait_in_report);
- break;
- case MCP2221_I2C_PARAM_OR_STATUS:
- switch (data[1]) {
- case MCP2221_SUCCESS:
- if ((mcp->txbuf[3] == MCP2221_I2C_SET_SPEED) &&
- (data[3] != MCP2221_I2C_SET_SPEED)) {
- mcp->status = -EAGAIN;
- break;
- }
- if (data[20] & MCP2221_I2C_MASK_ADDR_NACK) {
- mcp->status = -ENXIO;
- break;
- }
- mcp->status = mcp_get_i2c_eng_state(mcp, data, 8);
- break;
- default:
- mcp->status = -EIO;
- }
- complete(&mcp->wait_in_report);
- break;
- case MCP2221_I2C_GET_DATA:
- switch (data[1]) {
- case MCP2221_SUCCESS:
- if (data[2] == MCP2221_I2C_ADDR_NACK) {
- mcp->status = -ENXIO;
- break;
- }
- if (!mcp_get_i2c_eng_state(mcp, data, 2)
- && (data[3] == 0)) {
- mcp->status = 0;
- break;
- }
- if (data[3] == 127) {
- mcp->status = -EIO;
- break;
- }
- if (data[2] == MCP2221_I2C_READ_COMPL) {
- buf = mcp->rxbuf;
- memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]);
- mcp->rxbuf_idx = mcp->rxbuf_idx + data[3];
- mcp->status = 0;
- break;
- }
- mcp->status = -EIO;
- break;
- default:
- mcp->status = -EIO;
- }
- complete(&mcp->wait_in_report);
- break;
- case MCP2221_GPIO_GET:
- switch (data[1]) {
- case MCP2221_SUCCESS:
- if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
- (data[mcp->gp_idx + 1] == MCP2221_ALT_F_NOT_GPIOD)) {
- mcp->status = -ENOENT;
- } else {
- mcp->status = !!data[mcp->gp_idx];
- mcp->gpio_dir = data[mcp->gp_idx + 1];
- }
- break;
- default:
- mcp->status = -EAGAIN;
- }
- complete(&mcp->wait_in_report);
- break;
- case MCP2221_GPIO_SET:
- switch (data[1]) {
- case MCP2221_SUCCESS:
- if ((data[mcp->gp_idx] == MCP2221_ALT_F_NOT_GPIOV) ||
- (data[mcp->gp_idx - 1] == MCP2221_ALT_F_NOT_GPIOV)) {
- mcp->status = -ENOENT;
- } else {
- mcp->status = 0;
- }
- break;
- default:
- mcp->status = -EAGAIN;
- }
- complete(&mcp->wait_in_report);
- break;
- default:
- mcp->status = -EIO;
- complete(&mcp->wait_in_report);
- }
- return 1;
- }
- static int mcp2221_probe(struct hid_device *hdev,
- const struct hid_device_id *id)
- {
- int ret;
- struct mcp2221 *mcp;
- mcp = devm_kzalloc(&hdev->dev, sizeof(*mcp), GFP_KERNEL);
- if (!mcp)
- return -ENOMEM;
- ret = hid_parse(hdev);
- if (ret) {
- hid_err(hdev, "can't parse reports\n");
- return ret;
- }
- /*
- * This driver uses the .raw_event callback and therefore does not need any
- * HID_CONNECT_xxx flags.
- */
- ret = hid_hw_start(hdev, 0);
- if (ret) {
- hid_err(hdev, "can't start hardware\n");
- return ret;
- }
- hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", hdev->version >> 8,
- hdev->version & 0xff, hdev->name, hdev->phys);
- ret = hid_hw_open(hdev);
- if (ret) {
- hid_err(hdev, "can't open device\n");
- goto err_hstop;
- }
- mutex_init(&mcp->lock);
- init_completion(&mcp->wait_in_report);
- hid_set_drvdata(hdev, mcp);
- mcp->hdev = hdev;
- /* Set I2C bus clock diviser */
- if (i2c_clk_freq > 400)
- i2c_clk_freq = 400;
- if (i2c_clk_freq < 50)
- i2c_clk_freq = 50;
- mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3;
- mcp->adapter.owner = THIS_MODULE;
- mcp->adapter.class = I2C_CLASS_HWMON;
- mcp->adapter.algo = &mcp_i2c_algo;
- mcp->adapter.retries = 1;
- mcp->adapter.dev.parent = &hdev->dev;
- snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
- "MCP2221 usb-i2c bridge");
- ret = i2c_add_adapter(&mcp->adapter);
- if (ret) {
- hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret);
- goto err_i2c;
- }
- i2c_set_adapdata(&mcp->adapter, mcp);
- /* Setup GPIO chip */
- mcp->gc = devm_kzalloc(&hdev->dev, sizeof(*mcp->gc), GFP_KERNEL);
- if (!mcp->gc) {
- ret = -ENOMEM;
- goto err_gc;
- }
- mcp->gc->label = "mcp2221_gpio";
- mcp->gc->direction_input = mcp_gpio_direction_input;
- mcp->gc->direction_output = mcp_gpio_direction_output;
- mcp->gc->get_direction = mcp_gpio_get_direction;
- mcp->gc->set = mcp_gpio_set;
- mcp->gc->get = mcp_gpio_get;
- mcp->gc->ngpio = MCP_NGPIO;
- mcp->gc->base = -1;
- mcp->gc->can_sleep = 1;
- mcp->gc->parent = &hdev->dev;
- ret = devm_gpiochip_add_data(&hdev->dev, mcp->gc, mcp);
- if (ret)
- goto err_gc;
- return 0;
- err_gc:
- i2c_del_adapter(&mcp->adapter);
- err_i2c:
- hid_hw_close(mcp->hdev);
- err_hstop:
- hid_hw_stop(mcp->hdev);
- return ret;
- }
- static void mcp2221_remove(struct hid_device *hdev)
- {
- struct mcp2221 *mcp = hid_get_drvdata(hdev);
- i2c_del_adapter(&mcp->adapter);
- hid_hw_close(mcp->hdev);
- hid_hw_stop(mcp->hdev);
- }
- static const struct hid_device_id mcp2221_devices[] = {
- { HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_MCP2221) },
- { }
- };
- MODULE_DEVICE_TABLE(hid, mcp2221_devices);
- static struct hid_driver mcp2221_driver = {
- .name = "mcp2221",
- .id_table = mcp2221_devices,
- .probe = mcp2221_probe,
- .remove = mcp2221_remove,
- .raw_event = mcp2221_raw_event,
- };
- /* Register with HID core */
- module_hid_driver(mcp2221_driver);
- MODULE_AUTHOR("Rishi Gupta <[email protected]>");
- MODULE_DESCRIPTION("MCP2221 Microchip HID USB to I2C master bridge");
- MODULE_LICENSE("GPL v2");
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