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");