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 inline struct arizona_gpio *to_arizona_gpio(struct gpio_chip *chip)
 32{
 33	return container_of(chip, struct arizona_gpio, gpio_chip);
 34}
 35
 36static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
 37{
 38	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
 39	struct arizona *arizona = arizona_gpio->arizona;
 40
 41	return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
 42				  ARIZONA_GPN_DIR, ARIZONA_GPN_DIR);
 43}
 44
 45static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
 46{
 47	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
 48	struct arizona *arizona = arizona_gpio->arizona;
 49	unsigned int val;
 50	int ret;
 51
 52	ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
 53	if (ret < 0)
 54		return ret;
 55
 56	if (val & ARIZONA_GPN_LVL)
 57		return 1;
 58	else
 59		return 0;
 60}
 61
 62static int arizona_gpio_direction_out(struct gpio_chip *chip,
 63				     unsigned offset, int value)
 64{
 65	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
 66	struct arizona *arizona = arizona_gpio->arizona;
 67
 68	if (value)
 69		value = ARIZONA_GPN_LVL;
 70
 71	return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
 72				  ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
 73}
 74
 75static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 76{
 77	struct arizona_gpio *arizona_gpio = to_arizona_gpio(chip);
 78	struct arizona *arizona = arizona_gpio->arizona;
 79
 80	if (value)
 81		value = ARIZONA_GPN_LVL;
 82
 83	regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
 84			   ARIZONA_GPN_LVL, value);
 85}
 86
 87static struct gpio_chip template_chip = {
 88	.label			= "arizona",
 89	.owner			= THIS_MODULE,
 90	.direction_input	= arizona_gpio_direction_in,
 91	.get			= arizona_gpio_get,
 92	.direction_output	= arizona_gpio_direction_out,
 93	.set			= arizona_gpio_set,
 94	.can_sleep		= true,
 95};
 96
 97static int arizona_gpio_probe(struct platform_device *pdev)
 98{
 99	struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
100	struct arizona_pdata *pdata = dev_get_platdata(arizona->dev);
101	struct arizona_gpio *arizona_gpio;
102	int ret;
103
104	arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
105				    GFP_KERNEL);
106	if (arizona_gpio == NULL)
107		return -ENOMEM;
108
109	arizona_gpio->arizona = arizona;
110	arizona_gpio->gpio_chip = template_chip;
111	arizona_gpio->gpio_chip.dev = &pdev->dev;
112#ifdef CONFIG_OF_GPIO
113	arizona_gpio->gpio_chip.of_node = arizona->dev->of_node;
114#endif
115
116	switch (arizona->type) {
117	case WM5102:
118	case WM5110:
119	case WM8997:
120		arizona_gpio->gpio_chip.ngpio = 5;
121		break;
122	default:
123		dev_err(&pdev->dev, "Unknown chip variant %d\n",
124			arizona->type);
125		return -EINVAL;
126	}
127
128	if (pdata && pdata->gpio_base)
129		arizona_gpio->gpio_chip.base = pdata->gpio_base;
130	else
131		arizona_gpio->gpio_chip.base = -1;
132
133	ret = gpiochip_add(&arizona_gpio->gpio_chip);
134	if (ret < 0) {
135		dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
136			ret);
137		goto err;
138	}
139
140	platform_set_drvdata(pdev, arizona_gpio);
141
142	return ret;
143
144err:
145	return ret;
146}
147
148static int arizona_gpio_remove(struct platform_device *pdev)
149{
150	struct arizona_gpio *arizona_gpio = platform_get_drvdata(pdev);
151
152	return gpiochip_remove(&arizona_gpio->gpio_chip);
153}
154
155static struct platform_driver arizona_gpio_driver = {
156	.driver.name	= "arizona-gpio",
157	.driver.owner	= THIS_MODULE,
158	.probe		= arizona_gpio_probe,
159	.remove		= arizona_gpio_remove,
160};
161
162module_platform_driver(arizona_gpio_driver);
163
164MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
165MODULE_DESCRIPTION("GPIO interface for Arizona devices");
166MODULE_LICENSE("GPL");
167MODULE_ALIAS("platform:arizona-gpio");