drivers/input/touchscreen/cyttsp_i2c.c

   1 /*
   2  * Source for:
   3  * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
   4  * For use with Cypress Txx3xx parts.
   5  * Supported parts include:
   6  * CY8CTST341
   7  * CY8CTMA340
   8  *
   9  * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
  10  * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * version 2, and only version 2, as published by the
  15  * Free Software Foundation.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  25  *
  26  * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
  27  *
  28  */
  29
  30 #include "cyttsp_core.h"
  31
  32 #include <linux/i2c.h>
  33 #include <linux/input.h>
  34
  35 #define CY_I2C_DATA_SIZE        128
  36
  37 static int cyttsp_i2c_read_block_data(struct cyttsp *ts,
  38                                       u8 addr, u8 length, void *values)
  39 {
  40         struct i2c_client *client = to_i2c_client(ts->dev);
  41         struct i2c_msg msgs[] = {
  42                 {
  43                         .addr = client->addr,
  44                         .flags = 0,
  45                         .len = 1,
  46                         .buf = &addr,
  47                 },
  48                 {
  49                         .addr = client->addr,
  50                         .flags = I2C_M_RD,
  51                         .len = length,
  52                         .buf = values,
  53                 },
  54         };
  55         int retval;
  56
  57         retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
  58         if (retval < 0)
  59                 return retval;
  60
  61         return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
  62 }
  63
  64 static int cyttsp_i2c_write_block_data(struct cyttsp *ts,
  65                                        u8 addr, u8 length, const void *values)
  66 {
  67         struct i2c_client *client = to_i2c_client(ts->dev);
  68         int retval;
  69
  70         ts->xfer_buf[0] = addr;
  71         memcpy(&ts->xfer_buf[1], values, length);
  72
  73         retval = i2c_master_send(client, ts->xfer_buf, length + 1);
  74
  75         return retval < 0 ? retval : 0;
  76 }
  77
  78 static const struct cyttsp_bus_ops cyttsp_i2c_bus_ops = {
  79         .bustype        = BUS_I2C,
  80         .write          = cyttsp_i2c_write_block_data,
  81         .read           = cyttsp_i2c_read_block_data,
  82 };
  83
  84 static int cyttsp_i2c_probe(struct i2c_client *client,
  85                                       const struct i2c_device_id *id)
  86 {
  87         struct cyttsp *ts;
  88
  89         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
  90                 dev_err(&client->dev, "I2C functionality not Supported\n");
  91                 return -EIO;
  92         }
  93
  94         ts = cyttsp_probe(&cyttsp_i2c_bus_ops, &client->dev, client->irq,
  95                           CY_I2C_DATA_SIZE);
  96
  97         if (IS_ERR(ts))
  98                 return PTR_ERR(ts);
  99
 100         i2c_set_clientdata(client, ts);
 101
 102         return 0;
 103 }
 104
 105 static int cyttsp_i2c_remove(struct i2c_client *client)
 106 {
 107         struct cyttsp *ts = i2c_get_clientdata(client);
 108
 109         cyttsp_remove(ts);
 110
 111         return 0;
 112 }
 113
 114 static const struct i2c_device_id cyttsp_i2c_id[] = {
 115         { CY_I2C_NAME, 0 },
 116         { }
 117 };
 118 MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id);
 119
 120 static struct i2c_driver cyttsp_i2c_driver = {
 121         .driver = {
 122                 .name   = CY_I2C_NAME,
 123                 .owner  = THIS_MODULE,
 124                 .pm     = &cyttsp_pm_ops,
 125         },
 126         .probe          = cyttsp_i2c_probe,
 127         .remove         = cyttsp_i2c_remove,
 128         .id_table       = cyttsp_i2c_id,
 129 };
 130
 131 module_i2c_driver(cyttsp_i2c_driver);
 132
 133 MODULE_LICENSE("GPL");
 134 MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
 135 MODULE_AUTHOR("Cypress");
 136 MODULE_ALIAS("i2c:cyttsp");