SmartAudio/lichee/linux-4.9/drivers/input/touchscreen/focaltech_touch/focaltech_i2c.c

/*
 *
 * FocalTech TouchScreen driver.
 *
 * Copyright (c) 2010-2017, 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: fupeipei
*
*   Created: 2016-08-04
*
*  Abstract: i2c communication with TP
*
*   Version: v1.0
*
* Revision History:
*        v1.0:
*            First release. By fupeipei 2016-08-04
************************************************************************/

/*****************************************************************************
* Included header files
*****************************************************************************/
#include "focaltech_core.h"

/*****************************************************************************
* Private constant and macro definitions using #define
*****************************************************************************/

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

/*****************************************************************************
* Static variables
*****************************************************************************/
static DEFINE_MUTEX(i2c_rw_access);

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

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

/*****************************************************************************
* functions body
*****************************************************************************/

/************************************************************************
* Name: fts_i2c_read
* Brief: i2c read
* Input: i2c info, write buf, write len, read buf, read len
* Output: get data in the 3rd buf
* Return: fail <0
***********************************************************************/
int fts_i2c_read(struct i2c_client *client, char *writebuf,int writelen, char *readbuf, int readlen)
{
    int ret;

    mutex_lock(&i2c_rw_access);

    if (readlen > 0)
    {
        if (writelen > 0)
        {
            struct i2c_msg msgs[] =
            {
                {
                    .addr = client->addr,
                    .flags = 0,
                    .len = writelen,
                    .buf = writebuf,
                },
                {
                    .addr = client->addr,
                    .flags = I2C_M_RD,
                    .len = readlen,
                    .buf = readbuf,
                },
            };
            ret = i2c_transfer(client->adapter, msgs, 2);
            if (ret < 0)
            {
                FTS_ERROR("[IIC]: i2c_transfer(write) error, ret=%d!!", ret);
            }
        }
        else
        {
            struct i2c_msg msgs[] =
            {
                {
                    .addr = client->addr,
                    .flags = I2C_M_RD,
                    .len = readlen,
                    .buf = readbuf,
                },
            };
            ret = i2c_transfer(client->adapter, msgs, 1);
            if (ret < 0)
            {
                FTS_ERROR("[IIC]: i2c_transfer(read) error, ret=%d!!", ret);
            }
        }
    }

    mutex_unlock(&i2c_rw_access);
    return ret;
}

/************************************************************************
* Name: fts_i2c_write
* Brief: i2c write
* Input: i2c info, write buf, write len
* Output: no
* Return: fail <0
***********************************************************************/
int fts_i2c_write(struct i2c_client *client, char *writebuf, int writelen)
{
    int ret = 0;

    mutex_lock(&i2c_rw_access);
    if (writelen > 0)
    {
        struct i2c_msg msgs[] =
        {
            {
                .addr = client->addr,
                .flags = 0,
                .len = writelen,
                .buf = writebuf,
            },
        };
        ret = i2c_transfer(client->adapter, msgs, 1);
        if (ret < 0)
        {
            FTS_ERROR("%s: i2c_transfer(write) error, ret=%d", __func__, ret);
        }
    }
    mutex_unlock(&i2c_rw_access);

    return ret;
}

/************************************************************************
* Name: fts_i2c_write_reg
* Brief: write register
* Input: i2c info, reg address, reg value
* Output: no
* Return: fail <0
***********************************************************************/
int fts_i2c_write_reg(struct i2c_client *client, u8 regaddr, u8 regvalue)
{
    u8 buf[2] = {0};

    buf[0] = regaddr;
    buf[1] = regvalue;
    return fts_i2c_write(client, buf, sizeof(buf));
}

/************************************************************************
* Name: fts_i2c_read_reg
* Brief: read register
* Input: i2c info, reg address, reg value
* Output: get reg value
* Return: fail <0
***********************************************************************/
int fts_i2c_read_reg(struct i2c_client *client, u8 regaddr, u8 *regvalue)
{
    return fts_i2c_read(client, &regaddr, 1, regvalue, 1);
}

/************************************************************************
* Name: fts_i2c_init
* Brief: fts i2c init
* Input:
* Output:
* Return:
***********************************************************************/
int fts_i2c_init(void)
{
    FTS_FUNC_ENTER();

    FTS_FUNC_EXIT();
    return 0;
}
/************************************************************************
* Name: fts_i2c_exit
* Brief: fts i2c exit
* Input:
* Output:
* Return:
***********************************************************************/
int fts_i2c_exit(void)
{
    FTS_FUNC_ENTER();

    FTS_FUNC_EXIT();
    return 0;
}