arch/arm/mach-omap2/common-board-devices.c

   1 /*
   2  * common-board-devices.c
   3  *
   4  * Copyright (C) 2011 CompuLab, Ltd.
   5  * Author: Mike Rapoport <mike@compulab.co.il>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * version 2 as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  19  * 02110-1301 USA
  20  *
  21  */
  22
  23 #include <linux/gpio.h>
  24 #include <linux/spi/spi.h>
  25 #include <linux/spi/ads7846.h>
  26
  27 #include <linux/platform_data/spi-omap2-mcspi.h>
  28
  29 #include "common.h"
  30 #include "common-board-devices.h"
  31
  32 #if IS_ENABLED(CONFIG_TOUCHSCREEN_ADS7846)
  33 static struct omap2_mcspi_device_config ads7846_mcspi_config = {
  34         .turbo_mode     = 0,
  35 };
  36
  37 static struct ads7846_platform_data ads7846_config = {
  38         .x_max                  = 0x0fff,
  39         .y_max                  = 0x0fff,
  40         .x_plate_ohms           = 180,
  41         .pressure_max           = 255,
  42         .debounce_max           = 10,
  43         .debounce_tol           = 3,
  44         .debounce_rep           = 1,
  45         .gpio_pendown           = -EINVAL,
  46         .keep_vref_on           = 1,
  47 };
  48
  49 static struct spi_board_info ads7846_spi_board_info __initdata = {
  50         .modalias               = "ads7846",
  51         .bus_num                = -EINVAL,
  52         .chip_select            = 0,
  53         .max_speed_hz           = 1500000,
  54         .controller_data        = &ads7846_mcspi_config,
  55         .irq                    = -EINVAL,
  56         .platform_data          = &ads7846_config,
  57 };
  58
  59 void __init omap_ads7846_init(int bus_num, int gpio_pendown, int gpio_debounce,
  60                               struct ads7846_platform_data *board_pdata)
  61 {
  62         struct spi_board_info *spi_bi = &ads7846_spi_board_info;
  63         int err;
  64
  65         /*
  66          * If a board defines get_pendown_state() function, request the pendown
  67          * GPIO and set the GPIO debounce time.
  68          * If a board does not define the get_pendown_state() function, then
  69          * the ads7846 driver will setup the pendown GPIO itself.
  70          */
  71         if (board_pdata && board_pdata->get_pendown_state) {
  72                 err = gpio_request_one(gpio_pendown, GPIOF_IN, "TSPenDown");
  73                 if (err) {
  74                         pr_err("Couldn't obtain gpio for TSPenDown: %d\n", err);
  75                         return;
  76                 }
  77
  78                 if (gpio_debounce)
  79                         gpio_set_debounce(gpio_pendown, gpio_debounce);
  80
  81                 gpio_export(gpio_pendown, 0);
  82         }
  83
  84         spi_bi->bus_num = bus_num;
  85         spi_bi->irq     = gpio_to_irq(gpio_pendown);
  86
  87         ads7846_config.gpio_pendown = gpio_pendown;
  88
  89         if (board_pdata) {
  90                 board_pdata->gpio_pendown = gpio_pendown;
  91                 board_pdata->gpio_pendown_debounce = gpio_debounce;
  92                 spi_bi->platform_data = board_pdata;
  93         }
  94
  95         spi_register_board_info(&ads7846_spi_board_info, 1);
  96 }
  97 #else
  98 void __init omap_ads7846_init(int bus_num, int gpio_pendown, int gpio_debounce,
  99                               struct ads7846_platform_data *board_pdata)
 100 {
 101 }
 102 #endif