LXR linux/drivers/gpio/gpio-arizona.c

   1/*
   2 * gpiolib support for Wolfson Arizona class devices
   3 *
   4 * Copyright 2012 Wolfson Microelectronics PLC.
   5 *
   6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7 *
   8 *  This program is free software; you can redistribute  it and/or modify it
   9 *  under  the terms of  the GNU General  Public License as published by the
  10 *  Free Software Foundation;  either version 2 of the  License, or (at your
  11 *  option) any later version.
  12 *
  13 */
  14
  15#include <linux/kernel.h>
  16#include <linux/slab.h>
  17#include <linux/module.h>
  18#include <linux/gpio.h>
  19#include <linux/platform_device.h>
  20#include <linux/seq_file.h>
  21
  22#include <linux/mfd/arizona/core.h>
  23#include <linux/mfd/arizona/pdata.h>
  24#include <linux/mfd/arizona/registers.h>
  25
  26struct arizona_gpio {
  27        struct arizona *arizona;
  28        struct gpio_chip gpio_chip;
  29};
  30
  31static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
  32{
  33        struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
  34        struct arizona *arizona = arizona_gpio->arizona;
  35
  36        return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
  37                                  ARIZONA_GPN_DIR, ARIZONA_GPN_DIR);
  38}
  39
  40static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
  41{
  42        struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
  43        struct arizona *arizona = arizona_gpio->arizona;
  44        unsigned int val;
  45        int ret;
  46
  47        ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
  48        if (ret < 0)
  49                return ret;
  50
  51        if (val & ARIZONA_GPN_LVL)
  52                return 1;
  53        else
  54                return 0;
  55}
  56
  57static int arizona_gpio_direction_out(struct gpio_chip *chip,
  58                                     unsigned offset, int value)
  59{
  60        struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
  61        struct arizona *arizona = arizona_gpio->arizona;
  62
  63        if (value)
  64                value = ARIZONA_GPN_LVL;
  65
  66        return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
  67                                  ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
  68}
  69
  70static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
  71{
  72        struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
  73        struct arizona *arizona = arizona_gpio->arizona;
  74
  75        if (value)
  76                value = ARIZONA_GPN_LVL;
  77
  78        regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
  79                           ARIZONA_GPN_LVL, value);
  80}
  81
  82static struct gpio_chip template_chip = {
  83        .label                  = "arizona",
  84        .owner                  = THIS_MODULE,
  85        .direction_input        = arizona_gpio_direction_in,
  86        .get                    = arizona_gpio_get,
  87        .direction_output       = arizona_gpio_direction_out,
  88        .set                    = arizona_gpio_set,
  89        .can_sleep              = true,
  90};
  91
  92static int arizona_gpio_probe(struct platform_device *pdev)
  93{
  94        struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
  95        struct arizona_pdata *pdata = dev_get_platdata(arizona->dev);
  96        struct arizona_gpio *arizona_gpio;
  97        int ret;
  98
  99        arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
 100                                    GFP_KERNEL);
 101        if (!arizona_gpio)
 102                return -ENOMEM;
 103
 104        arizona_gpio->arizona = arizona;
 105        arizona_gpio->gpio_chip = template_chip;
 106        arizona_gpio->gpio_chip.parent = &pdev->dev;
 107#ifdef CONFIG_OF_GPIO
 108        arizona_gpio->gpio_chip.of_node = arizona->dev->of_node;
 109#endif
 110
 111        switch (arizona->type) {
 112        case WM5102:
 113        case WM5110:
 114        case WM8280:
 115        case WM8997:
 116        case WM8998:
 117        case WM1814:
 118                arizona_gpio->gpio_chip.ngpio = 5;
 119                break;
 120        case WM1831:
 121        case CS47L24:
 122                arizona_gpio->gpio_chip.ngpio = 2;
 123                break;
 124        default:
 125                dev_err(&pdev->dev, "Unknown chip variant %d\n",
 126                        arizona->type);
 127                return -EINVAL;
 128        }
 129
 130        if (pdata && pdata->gpio_base)
 131                arizona_gpio->gpio_chip.base = pdata->gpio_base;
 132        else
 133                arizona_gpio->gpio_chip.base = -1;
 134
 135        ret = devm_gpiochip_add_data(&pdev->dev, &arizona_gpio->gpio_chip,
 136                                     arizona_gpio);
 137        if (ret < 0) {
 138                dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
 139                        ret);
 140                goto err;
 141        }
 142
 143        platform_set_drvdata(pdev, arizona_gpio);
 144
 145        return ret;
 146
 147err:
 148        return ret;
 149}
 150
 151static struct platform_driver arizona_gpio_driver = {
 152        .driver.name    = "arizona-gpio",
 153        .probe          = arizona_gpio_probe,
 154};
 155
 156module_platform_driver(arizona_gpio_driver);
 157
 158MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 159MODULE_DESCRIPTION("GPIO interface for Arizona devices");
 160MODULE_LICENSE("GPL");
 161MODULE_ALIAS("platform:arizona-gpio");
 162