drivers/input/touchscreen/tsc2005.c

   1 /*
   2  * TSC2005 touchscreen driver
   3  *
   4  * Copyright (C) 2006-2010 Nokia Corporation
   5  * Copyright (C) 2015 QWERTY Embedded Design
   6  * Copyright (C) 2015 EMAC Inc.
   7  *
   8  * Based on original tsc2005.c by Lauri Leukkunen <lauri.leukkunen@nokia.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18  * GNU General Public License for more details.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/input.h>
  23 #include <linux/spi/spi.h>
  24 #include <linux/regmap.h>
  25 #include "tsc200x-core.h"
  26
  27 static int tsc2005_cmd(struct device *dev, u8 cmd)
  28 {
  29         u8 tx = TSC200X_CMD | TSC200X_CMD_12BIT | cmd;
  30         struct spi_transfer xfer = {
  31                 .tx_buf         = &tx,
  32                 .len            = 1,
  33                 .bits_per_word  = 8,
  34         };
  35         struct spi_message msg;
  36         struct spi_device *spi = to_spi_device(dev);
  37         int error;
  38
  39         spi_message_init(&msg);
  40         spi_message_add_tail(&xfer, &msg);
  41
  42         error = spi_sync(spi, &msg);
  43         if (error) {
  44                 dev_err(dev, "%s: failed, command: %x, spi error: %d\n",
  45                         __func__, cmd, error);
  46                 return error;
  47         }
  48
  49         return 0;
  50 }
  51
  52 static int tsc2005_probe(struct spi_device *spi)
  53 {
  54         int error;
  55
  56         spi->mode = SPI_MODE_0;
  57         spi->bits_per_word = 8;
  58         if (!spi->max_speed_hz)
  59                 spi->max_speed_hz = TSC2005_SPI_MAX_SPEED_HZ;
  60
  61         error = spi_setup(spi);
  62         if (error)
  63                 return error;
  64
  65         return tsc200x_probe(&spi->dev, spi->irq, BUS_SPI,
  66                              devm_regmap_init_spi(spi, &tsc200x_regmap_config),
  67                              tsc2005_cmd);
  68 }
  69
  70 static int tsc2005_remove(struct spi_device *spi)
  71 {
  72         return tsc200x_remove(&spi->dev);
  73 }
  74
  75 static struct spi_driver tsc2005_driver = {
  76         .driver = {
  77                 .name   = "tsc2005",
  78                 .pm     = &tsc200x_pm_ops,
  79         },
  80         .probe  = tsc2005_probe,
  81         .remove = tsc2005_remove,
  82 };
  83 module_spi_driver(tsc2005_driver);
  84
  85 MODULE_AUTHOR("Michael Welling <mwelling@ieee.org>");
  86 MODULE_DESCRIPTION("TSC2005 Touchscreen Driver");
  87 MODULE_LICENSE("GPL");
  88 MODULE_ALIAS("spi:tsc2005");