drivers/input/touchscreen/cyttsp_i2c_common.c

   1 /*
   2  * cyttsp_i2c_common.c
   3  * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
   4  * For use with Cypress Txx3xx and Txx4xx parts.
   5  * Supported parts include:
   6  * CY8CTST341
   7  * CY8CTMA340
   8  * TMA4XX
   9  * TMA1036
  10  *
  11  * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
  12  * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * version 2, and only version 2, as published by the
  17  * Free Software Foundation.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * Contact Cypress Semiconductor at www.cypress.com <ttdrivers@cypress.com>
  25  *
  26  */
  27
  28 #include <linux/device.h>
  29 #include <linux/export.h>
  30 #include <linux/i2c.h>
  31 #include <linux/module.h>
  32 #include <linux/types.h>
  33
  34 #include "cyttsp4_core.h"
  35
  36 int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf,
  37                                       u16 addr, u8 length, void *values)
  38 {
  39         struct i2c_client *client = to_i2c_client(dev);
  40         u8 client_addr = client->addr | ((addr >> 8) & 0x1);
  41         u8 addr_lo = addr & 0xFF;
  42         struct i2c_msg msgs[] = {
  43                 {
  44                         .addr = client_addr,
  45                         .flags = 0,
  46                         .len = 1,
  47                         .buf = &addr_lo,
  48                 },
  49                 {
  50                         .addr = client_addr,
  51                         .flags = I2C_M_RD,
  52                         .len = length,
  53                         .buf = values,
  54                 },
  55         };
  56         int retval;
  57
  58         retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  59         if (retval < 0)
  60                 return retval;
  61
  62         return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
  63 }
  64 EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
  65
  66 int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
  67                                        u16 addr, u8 length, const void *values)
  68 {
  69         struct i2c_client *client = to_i2c_client(dev);
  70         u8 client_addr = client->addr | ((addr >> 8) & 0x1);
  71         u8 addr_lo = addr & 0xFF;
  72         struct i2c_msg msgs[] = {
  73                 {
  74                         .addr = client_addr,
  75                         .flags = 0,
  76                         .len = length + 1,
  77                         .buf = xfer_buf,
  78                 },
  79         };
  80         int retval;
  81
  82         xfer_buf[0] = addr_lo;
  83         memcpy(&xfer_buf[1], values, length);
  84
  85         retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  86         if (retval < 0)
  87                 return retval;
  88
  89         return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
  90 }
  91 EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
  92
  93
  94 MODULE_LICENSE("GPL");
  95 MODULE_AUTHOR("Cypress");