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 int cyttsp_i2c_read_block_data(struct device *dev, u8 *xfer_buf,
  35                                       u16 addr, u8 length, void *values)
  36 {
  37         struct i2c_client *client = to_i2c_client(dev);
  38         u8 client_addr = client->addr | ((addr >> 8) & 0x1);
  39         u8 addr_lo = addr & 0xFF;
  40         struct i2c_msg msgs[] = {
  41                 {
  42                         .addr = client_addr,
  43                         .flags = 0,
  44                         .len = 1,
  45                         .buf = &addr_lo,
  46                 },
  47                 {
  48                         .addr = client_addr,
  49                         .flags = I2C_M_RD,
  50                         .len = length,
  51                         .buf = values,
  52                 },
  53         };
  54         int retval;
  55
  56         retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  57         if (retval < 0)
  58                 return retval;
  59
  60         return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
  61 }
  62 EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
  63
  64 int cyttsp_i2c_write_block_data(struct device *dev, u8 *xfer_buf,
  65                                        u16 addr, u8 length, const void *values)
  66 {
  67         struct i2c_client *client = to_i2c_client(dev);
  68         u8 client_addr = client->addr | ((addr >> 8) & 0x1);
  69         u8 addr_lo = addr & 0xFF;
  70         struct i2c_msg msgs[] = {
  71                 {
  72                         .addr = client_addr,
  73                         .flags = 0,
  74                         .len = length + 1,
  75                         .buf = xfer_buf,
  76                 },
  77         };
  78         int retval;
  79
  80         xfer_buf[0] = addr_lo;
  81         memcpy(&xfer_buf[1], values, length);
  82
  83         retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  84         if (retval < 0)
  85                 return retval;
  86
  87         return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
  88 }
  89 EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
  90
  91
  92 MODULE_LICENSE("GPL");
  93 MODULE_AUTHOR("Cypress");