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/input.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/spi/spi.h>
  25 #include <linux/regmap.h>
  26 #include "tsc200x-core.h"
  27
  28 static const struct input_id tsc2005_input_id = {
  29         .bustype = BUS_SPI,
  30         .product = 2005,
  31 };
  32
  33 static int tsc2005_cmd(struct device *dev, u8 cmd)
  34 {
  35         u8 tx = TSC200X_CMD | TSC200X_CMD_12BIT | cmd;
  36         struct spi_transfer xfer = {
  37                 .tx_buf         = &tx,
  38                 .len            = 1,
  39                 .bits_per_word  = 8,
  40         };
  41         struct spi_message msg;
  42         struct spi_device *spi = to_spi_device(dev);
  43         int error;
  44
  45         spi_message_init(&msg);
  46         spi_message_add_tail(&xfer, &msg);
  47
  48         error = spi_sync(spi, &msg);
  49         if (error) {
  50                 dev_err(dev, "%s: failed, command: %x, spi error: %d\n",
  51                         __func__, cmd, error);
  52                 return error;
  53         }
  54
  55         return 0;
  56 }
  57
  58 static int tsc2005_probe(struct spi_device *spi)
  59 {
  60         int error;
  61
  62         spi->mode = SPI_MODE_0;
  63         spi->bits_per_word = 8;
  64         if (!spi->max_speed_hz)
  65                 spi->max_speed_hz = TSC2005_SPI_MAX_SPEED_HZ;
  66
  67         error = spi_setup(spi);
  68         if (error)
  69                 return error;
  70
  71         return tsc200x_probe(&spi->dev, spi->irq, &tsc2005_input_id,
  72                              devm_regmap_init_spi(spi, &tsc200x_regmap_config),
  73                              tsc2005_cmd);
  74 }
  75
  76 static int tsc2005_remove(struct spi_device *spi)
  77 {
  78         return tsc200x_remove(&spi->dev);
  79 }
  80
  81 #ifdef CONFIG_OF
  82 static const struct of_device_id tsc2005_of_match[] = {
  83         { .compatible = "ti,tsc2005" },
  84         { /* sentinel */ }
  85 };
  86 MODULE_DEVICE_TABLE(of, tsc2005_of_match);
  87 #endif
  88
  89 static struct spi_driver tsc2005_driver = {
  90         .driver = {
  91                 .name   = "tsc2005",
  92                 .of_match_table = of_match_ptr(tsc2005_of_match),
  93                 .pm     = &tsc200x_pm_ops,
  94         },
  95         .probe  = tsc2005_probe,
  96         .remove = tsc2005_remove,
  97 };
  98 module_spi_driver(tsc2005_driver);
  99
 100 MODULE_AUTHOR("Michael Welling <mwelling@ieee.org>");
 101 MODULE_DESCRIPTION("TSC2005 Touchscreen Driver");
 102 MODULE_LICENSE("GPL");
 103 MODULE_ALIAS("spi:tsc2005");