LXR linux/drivers/input/touchscreen/cyttsp_i2c

   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
  36int 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}
  64EXPORT_SYMBOL_GPL(cyttsp_i2c_read_block_data);
  65
  66int 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}
  91EXPORT_SYMBOL_GPL(cyttsp_i2c_write_block_data);
  92
  93
  94MODULE_LICENSE("GPL");
  95MODULE_AUTHOR("Cypress");
  96