android_kernel_samsung_sm8650-modules/focaltech_touch/focaltech_i2c.c

/*
 *
 * FocalTech TouchScreen driver.
 *
 * Copyright (c) 2012-2019, FocalTech Systems, Ltd., all rights reserved.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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.
 *
 */

/************************************************************************
*
* File Name: focaltech_i2c.c
*
* Author: Focaltech Driver Team
*
* Created: 2016-08-04
*
* Abstract: i2c communication with TP
*
* Version: v1.0
*
* Revision History:
*
************************************************************************/

/*****************************************************************************
* Included header files
*****************************************************************************/
#include "focaltech_core.h"
#include <linux/pm_runtime.h>

/*****************************************************************************
* Private constant and macro definitions using #define
*****************************************************************************/
#define I2C_RETRY_NUMBER                    3
#define I2C_BUF_LENGTH                      256

/*****************************************************************************
* Private enumerations, structures and unions using typedef
*****************************************************************************/

/*****************************************************************************
* Static variables
*****************************************************************************/
static struct fts_ts_data *ts_data;

/*****************************************************************************
* Global variable or extern global variabls/functions
*****************************************************************************/

/*****************************************************************************
* Static function prototypes
*****************************************************************************/

/*****************************************************************************
* functions body
*****************************************************************************/
static int fts_i2c_read(u8 *cmd, u32 cmdlen, u8 *data, u32 datalen)
{
	int ret = 0;
	int i = 0;
	struct i2c_msg msg_list[2];
	struct i2c_msg *msg = NULL;
	int msg_num = 0;

	/* must have data when read */
	if (!ts_data || !ts_data->client || !data || !datalen
		|| (datalen >= I2C_BUF_LENGTH) || (cmdlen >= I2C_BUF_LENGTH)) {
		FTS_ERROR("fts_data/client/cmdlen(%d)/data/datalen(%d) is invalid",
			cmdlen, datalen);
		return -EINVAL;
	}

	mutex_lock(&ts_data->bus_lock);
	memset(&msg_list[0], 0, sizeof(struct i2c_msg));
	memset(&msg_list[1], 0, sizeof(struct i2c_msg));
	memcpy(ts_data->bus_tx_buf, cmd, cmdlen);
	msg_list[0].addr = ts_data->client->addr;
	msg_list[0].flags = 0;
	msg_list[0].len = cmdlen;
	msg_list[0].buf = ts_data->bus_tx_buf;
	msg_list[1].addr = ts_data->client->addr;
	msg_list[1].flags = I2C_M_RD;
	msg_list[1].len = datalen;
	msg_list[1].buf = ts_data->bus_rx_buf;
	if (cmd && cmdlen) {
		msg = &msg_list[0];
		msg_num = 2;
	} else {
		msg = &msg_list[1];
		msg_num = 1;
	}

	for (i = 0; i < I2C_RETRY_NUMBER; i++) {
		ret = i2c_transfer(ts_data->client->adapter, msg, msg_num);
		if (ret < 0) {
#ifdef CONFIG_FTS_TRUSTED_TOUCH
#ifdef CONFIG_ARCH_QTI_VM
			if (atomic_read(&ts_data->trusted_touch_enabled) &&
					ret == -ECONNRESET) {
				pr_err("failed i2c read reacquiring session\n");
				pm_runtime_put_sync(
					ts_data->client->adapter->dev.parent);
				pm_runtime_get_sync(
					ts_data->client->adapter->dev.parent);
			}
#endif
#endif
			FTS_ERROR("i2c_transfer(read) fail,ret:%d", ret);
		} else {
			memcpy(data, ts_data->bus_rx_buf, datalen);
			break;
		}
	}

	if (ret < 0) {
#ifdef CONFIG_FTS_TRUSTED_TOUCH
#ifdef CONFIG_ARCH_QTI_VM
		pr_err("initiating abort due to i2c xfer failure\n");
		fts_ts_trusted_touch_tvm_i2c_failure_report(ts_data);
#endif
#endif
	}

	mutex_unlock(&ts_data->bus_lock);
	return ret;
}

static int fts_i2c_write(u8 *writebuf, u32 writelen)
{
	int ret = 0;
	int i = 0;
	struct i2c_msg msgs;

	if (!ts_data || !ts_data->client || !writebuf || !writelen
		|| (writelen >= I2C_BUF_LENGTH)) {
		FTS_ERROR("fts_data/client/data/datalen(%d) is invalid", writelen);
		return -EINVAL;
	}

	mutex_lock(&ts_data->bus_lock);
	memset(&msgs, 0, sizeof(struct i2c_msg));
	memcpy(ts_data->bus_tx_buf, writebuf, writelen);
	msgs.addr = ts_data->client->addr;
	msgs.flags = 0;
	msgs.len = writelen;
	msgs.buf = ts_data->bus_tx_buf;
	for (i = 0; i < I2C_RETRY_NUMBER; i++) {
		ret = i2c_transfer(ts_data->client->adapter, &msgs, 1);
		if (ret < 0) {
#ifdef CONFIG_FTS_TRUSTED_TOUCH
#ifdef CONFIG_ARCH_QTI_VM
			if (atomic_read(&ts_data->trusted_touch_enabled) &&
				ret == -ECONNRESET){
				pr_err("failed i2c write reacquiring session\n");
				pm_runtime_put_sync(
					ts_data->client->adapter->dev.parent);
				pm_runtime_get_sync(
					ts_data->client->adapter->dev.parent);
			}
#endif
#endif
			FTS_ERROR("i2c_transfer(write) fail,ret:%d", ret);
		} else {
			break;
		}
	}

	if (ret < 0) {
#ifdef CONFIG_FTS_TRUSTED_TOUCH
#ifdef CONFIG_ARCH_QTI_VM
		pr_err("initiating abort due to i2c xfer failure\n");
		fts_ts_trusted_touch_tvm_i2c_failure_report(ts_data);
#endif
#endif
	}
	mutex_unlock(&ts_data->bus_lock);
	return ret;
}

static int fts_i2c_init(struct fts_ts_data *ts_data)
{
	FTS_FUNC_ENTER();
	ts_data->bus_tx_buf = kzalloc(I2C_BUF_LENGTH, GFP_KERNEL);
	if (ts_data->bus_tx_buf == NULL) {
		FTS_ERROR("failed to allocate memory for bus_tx_buf");
		return -ENOMEM;
	}

	ts_data->bus_rx_buf = kzalloc(I2C_BUF_LENGTH, GFP_KERNEL);
	if (ts_data->bus_rx_buf == NULL) {
		FTS_ERROR("failed to allocate memory for bus_rx_buf");
		return -ENOMEM;
	}
	FTS_FUNC_EXIT();
	return 0;
}

static int fts_i2c_exit(struct fts_ts_data *ts_data)
{
	FTS_FUNC_ENTER();
	if (ts_data && ts_data->bus_tx_buf) {
		kfree(ts_data->bus_tx_buf);
		ts_data->bus_tx_buf = NULL;
	}

	if (ts_data && ts_data->bus_rx_buf) {
		kfree(ts_data->bus_rx_buf);
		ts_data->bus_rx_buf = NULL;
	}
	FTS_FUNC_EXIT();
	return 0;
}

/*****************************************************************************
 * Private constant and macro definitions using #define
 ****************************************************************************/
#define SPI_RETRY_NUMBER            3
#define CS_HIGH_DELAY               150 /* unit: us */
#define SPI_BUF_LENGTH              256

#define DATA_CRC_EN                 0x20
#define WRITE_CMD                   0x00
#define READ_CMD                    (0x80 | DATA_CRC_EN)

#define SPI_DUMMY_BYTE              3
#define SPI_HEADER_LENGTH           6   /*CRC*/

/*****************************************************************************
 * functions body
 ****************************************************************************/
/* spi interface */
static int fts_spi_transfer(u8 *tx_buf, u8 *rx_buf, u32 len)
{
	int ret = 0;
	struct spi_device *spi = fts_data->spi;
	struct spi_message msg;
	struct spi_transfer xfer = {
		.tx_buf = tx_buf,
		.rx_buf = rx_buf,
		.len    = len,
	};

	spi_message_init(&msg);
	spi_message_add_tail(&xfer, &msg);

	ret = spi_sync(spi, &msg);
	if (ret) {
		FTS_ERROR("spi_sync fail,ret:%d", ret);
		return ret;
	}

	return ret;
}

static void crckermit(u8 *data, u32 len, u16 *crc_out)
{
	u32 i = 0;
	u32 j = 0;
	u16 crc = 0xFFFF;

	for (i = 0; i < len; i++) {
		crc ^= data[i];
		for (j = 0; j < 8; j++) {
			if (crc & 0x01)
				crc = (crc >> 1) ^ 0x8408;
			else
				crc = (crc >> 1);
		}
	}

	*crc_out = crc;
}

static int rdata_check(u8 *rdata, u32 rlen)
{
	u16 crc_calc = 0;
	u16 crc_read = 0;

	crckermit(rdata, rlen - 2, &crc_calc);
	crc_read = (u16)(rdata[rlen - 1] << 8) + rdata[rlen - 2];
	if (crc_calc != crc_read)
		return -EIO;

	return 0;
}

static int fts_spi_write(u8 *writebuf, u32 writelen)
{
	int ret = 0;
	int i = 0;
	struct fts_ts_data *ts_data = fts_data;
	u8 *txbuf = NULL;
	u8 *rxbuf = NULL;
	u32 txlen = 0;
	u32 txlen_need = writelen + SPI_HEADER_LENGTH + ts_data->dummy_byte;
	u32 datalen = writelen - 1;

	if (!writebuf || !writelen) {
		FTS_ERROR("writebuf/len is invalid");
		return -EINVAL;
	}

	mutex_lock(&ts_data->bus_lock);
	if (txlen_need > SPI_BUF_LENGTH) {
		txbuf = kzalloc(txlen_need, GFP_KERNEL);
		if (txbuf == NULL) {
			FTS_ERROR("txbuf malloc fail");
			ret = -ENOMEM;
			goto err_write;
		}

		rxbuf = kzalloc(txlen_need, GFP_KERNEL);
		if (rxbuf == NULL) {
			FTS_ERROR("rxbuf malloc fail");
			ret = -ENOMEM;
			goto err_write;
		}
	} else {
		txbuf = ts_data->bus_tx_buf;
		rxbuf = ts_data->bus_rx_buf;
		memset(txbuf, 0x0, SPI_BUF_LENGTH);
		memset(rxbuf, 0x0, SPI_BUF_LENGTH);
	}

	txbuf[txlen++] = writebuf[0];
	txbuf[txlen++] = WRITE_CMD;
	txbuf[txlen++] = (datalen >> 8) & 0xFF;
	txbuf[txlen++] = datalen & 0xFF;
	if (datalen > 0) {
		txlen = txlen + SPI_DUMMY_BYTE;
		memcpy(&txbuf[txlen], &writebuf[1], datalen);
		txlen = txlen + datalen;
	}

	for (i = 0; i < SPI_RETRY_NUMBER; i++) {
		ret = fts_spi_transfer(txbuf, rxbuf, txlen);
		if ((ret == 0) && ((rxbuf[3] & 0xA0) == 0))
			break;

		FTS_DEBUG("data write(addr:%x),status:%x,retry:%d,ret:%d",
				writebuf[0], rxbuf[3], i, ret);
		ret = -EIO;
		udelay(CS_HIGH_DELAY);
	}

	if (ret < 0) {
		FTS_ERROR("data write(addr:%x) fail,status:%x,ret:%d",
				writebuf[0], rxbuf[3], ret);
	}

err_write:
	if (txlen_need > SPI_BUF_LENGTH) {
		kfree(txbuf);
		kfree(rxbuf);
	}

	udelay(CS_HIGH_DELAY);
	mutex_unlock(&ts_data->bus_lock);
	return ret;
}

static int fts_spi_read(u8 *cmd, u32 cmdlen, u8 *data, u32 datalen)
{
	int ret = 0;
	int i = 0;
	u8 *txbuf = NULL;
	u8 *rxbuf = NULL;
	u32 txlen = 0;
	u32 txlen_need = datalen + SPI_HEADER_LENGTH + ts_data->dummy_byte;
	u8 ctrl = READ_CMD;
	u32 dp = 0;

	if (!cmd || !cmdlen || !data || !datalen) {
		FTS_ERROR("cmd/cmdlen/data/datalen is invalid");
		return -EINVAL;
	}

	mutex_lock(&ts_data->bus_lock);
	if (txlen_need > SPI_BUF_LENGTH) {
		txbuf = kzalloc(txlen_need, GFP_KERNEL);
		if (txbuf == NULL) {
			FTS_ERROR("txbuf malloc fail");
			ret = -ENOMEM;
			goto err_read;
		}

		rxbuf = kzalloc(txlen_need, GFP_KERNEL);
		if (rxbuf == NULL) {
			FTS_ERROR("rxbuf malloc fail");
			ret = -ENOMEM;
			goto err_read;
		}
	} else {
		txbuf = ts_data->bus_tx_buf;
		rxbuf = ts_data->bus_rx_buf;
		memset(txbuf, 0x0, SPI_BUF_LENGTH);
		memset(rxbuf, 0x0, SPI_BUF_LENGTH);
	}

	txbuf[txlen++] = cmd[0];
	txbuf[txlen++] = ctrl;
	txbuf[txlen++] = (datalen >> 8) & 0xFF;
	txbuf[txlen++] = datalen & 0xFF;
	dp = txlen + SPI_DUMMY_BYTE;
	txlen = dp + datalen;
	if (ctrl & DATA_CRC_EN)
		txlen = txlen + 2;

	for (i = 0; i < SPI_RETRY_NUMBER; i++) {
		ret = fts_spi_transfer(txbuf, rxbuf, txlen);
		if ((ret == 0) && ((rxbuf[3] & 0xA0) == 0)) {
			memcpy(data, &rxbuf[dp], datalen);
			/* crc check */
			if (ctrl & DATA_CRC_EN) {
				ret = rdata_check(&rxbuf[dp], txlen - dp);
				if (ret < 0) {
					FTS_DEBUG("data read(addr:%x) crc abnormal,retry:%d",
							cmd[0], i);
					udelay(CS_HIGH_DELAY);
					continue;
				}
			}
			break;
		}

		FTS_DEBUG("data read(addr:%x) status:%x,retry:%d,ret:%d",
				cmd[0], rxbuf[3], i, ret);
		ret = -EIO;
		udelay(CS_HIGH_DELAY);
	}

	if (ret < 0) {
		FTS_ERROR("data read(addr:%x) %s,status:%x,ret:%d", cmd[0],
				(i >= SPI_RETRY_NUMBER) ? "crc abnormal" : "fail",
				rxbuf[3], ret);
	}

err_read:
	if (txlen_need > SPI_BUF_LENGTH) {
		kfree(txbuf);
		kfree(rxbuf);
	}

	udelay(CS_HIGH_DELAY);
	mutex_unlock(&ts_data->bus_lock);
	return ret;
}

static int fts_spi_init(struct fts_ts_data *ts_data)
{
	FTS_FUNC_ENTER();
	ts_data->bus_tx_buf = kzalloc(SPI_BUF_LENGTH, GFP_KERNEL);
	if (ts_data->bus_tx_buf == NULL) {
		FTS_ERROR("failed to allocate memory for bus_tx_buf");
		return -ENOMEM;
	}

	ts_data->bus_rx_buf = kzalloc(SPI_BUF_LENGTH, GFP_KERNEL);
	if (ts_data->bus_rx_buf == NULL) {
		FTS_ERROR("failed to allocate memory for bus_rx_buf");
		return -ENOMEM;
	}

	ts_data->dummy_byte = SPI_DUMMY_BYTE;
	FTS_FUNC_EXIT();
	return 0;
}

static int fts_spi_exit(struct fts_ts_data *ts_data)
{
	FTS_FUNC_ENTER();
	if (ts_data && ts_data->bus_tx_buf) {
		kfree(ts_data->bus_tx_buf);
		ts_data->bus_tx_buf = NULL;
	}

	if (ts_data && ts_data->bus_rx_buf) {
		kfree(ts_data->bus_rx_buf);
		ts_data->bus_rx_buf = NULL;
	}
	FTS_FUNC_EXIT();
	return 0;
}

int fts_read(u8 *cmd, u32 cmdlen, u8 *data, u32 datalen)
{
	int ret = 0;

	if (ts_data->bus_type == BUS_TYPE_I2C)
		ret = fts_i2c_read(cmd, cmdlen, data, datalen);
	else
		ret = fts_spi_read(cmd, cmdlen, data, datalen);

	return ret;
}

int fts_write(u8 *writebuf, u32 writelen)
{
	int ret = 0;

	if (ts_data->bus_type == BUS_TYPE_I2C)
		ret = fts_i2c_write(writebuf, writelen);
	else
		ret = fts_spi_write(writebuf, writelen);

	return ret;
}

int fts_read_reg(u8 addr, u8 *value)
{
	return fts_read(&addr, 1, value, 1);
}

int fts_write_reg(u8 addr, u8 value)
{
	u8 buf[2] = { 0 };

	buf[0] = addr;
	buf[1] = value;
	return fts_write(buf, sizeof(buf));
}

int fts_bus_init(struct fts_ts_data *_ts_data)
{
	ts_data = _ts_data;

	if (ts_data->bus_type == BUS_TYPE_I2C)
		return fts_i2c_init(ts_data);

	return fts_spi_init(ts_data);
}

int fts_bus_exit(struct fts_ts_data *ts_data)
{
	if (ts_data->bus_type == BUS_TYPE_I2C)
		return fts_i2c_exit(ts_data);

	return fts_spi_exit(ts_data);
}