2 * gpiolib support for Wolfson Arizona class devices
4 * Copyright 2012 Wolfson Microelectronics PLC.
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
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.
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/pm_runtime.h>
21 #include <linux/seq_file.h>
23 #include <linux/mfd/arizona/core.h>
24 #include <linux/mfd/arizona/pdata.h>
25 #include <linux/mfd/arizona/registers.h>
28 struct arizona *arizona;
29 struct gpio_chip gpio_chip;
32 static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
34 struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
35 struct arizona *arizona = arizona_gpio->arizona;
36 bool persistent = gpiochip_line_is_persistent(chip, offset);
40 ret = regmap_update_bits_check(arizona->regmap,
41 ARIZONA_GPIO1_CTRL + offset,
42 ARIZONA_GPN_DIR, ARIZONA_GPN_DIR,
47 if (change && persistent) {
48 pm_runtime_mark_last_busy(chip->parent);
49 pm_runtime_put_autosuspend(chip->parent);
55 static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
57 struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
58 struct arizona *arizona = arizona_gpio->arizona;
59 unsigned int reg, val;
62 reg = ARIZONA_GPIO1_CTRL + offset;
63 ret = regmap_read(arizona->regmap, reg, &val);
67 /* Resume to read actual registers for input pins */
68 if (val & ARIZONA_GPN_DIR) {
69 ret = pm_runtime_get_sync(chip->parent);
71 dev_err(chip->parent, "Failed to resume: %d\n", ret);
72 pm_runtime_put_autosuspend(chip->parent);
76 /* Register is cached, drop it to ensure a physical read */
77 ret = regcache_drop_region(arizona->regmap, reg, reg);
79 dev_err(chip->parent, "Failed to drop cache: %d\n",
81 pm_runtime_put_autosuspend(chip->parent);
85 ret = regmap_read(arizona->regmap, reg, &val);
87 pm_runtime_put_autosuspend(chip->parent);
91 pm_runtime_mark_last_busy(chip->parent);
92 pm_runtime_put_autosuspend(chip->parent);
95 if (val & ARIZONA_GPN_LVL)
101 static int arizona_gpio_direction_out(struct gpio_chip *chip,
102 unsigned offset, int value)
104 struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
105 struct arizona *arizona = arizona_gpio->arizona;
106 bool persistent = gpiochip_line_is_persistent(chip, offset);
110 ret = regmap_read(arizona->regmap, ARIZONA_GPIO1_CTRL + offset, &val);
114 if ((val & ARIZONA_GPN_DIR) && persistent) {
115 ret = pm_runtime_get_sync(chip->parent);
117 dev_err(chip->parent, "Failed to resume: %d\n", ret);
118 pm_runtime_put(chip->parent);
124 value = ARIZONA_GPN_LVL;
126 return regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
127 ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, value);
130 static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
132 struct arizona_gpio *arizona_gpio = gpiochip_get_data(chip);
133 struct arizona *arizona = arizona_gpio->arizona;
136 value = ARIZONA_GPN_LVL;
138 regmap_update_bits(arizona->regmap, ARIZONA_GPIO1_CTRL + offset,
139 ARIZONA_GPN_LVL, value);
142 static const struct gpio_chip template_chip = {
144 .owner = THIS_MODULE,
145 .direction_input = arizona_gpio_direction_in,
146 .get = arizona_gpio_get,
147 .direction_output = arizona_gpio_direction_out,
148 .set = arizona_gpio_set,
152 static int arizona_gpio_probe(struct platform_device *pdev)
154 struct arizona *arizona = dev_get_drvdata(pdev->dev.parent);
155 struct arizona_pdata *pdata = dev_get_platdata(arizona->dev);
156 struct arizona_gpio *arizona_gpio;
159 arizona_gpio = devm_kzalloc(&pdev->dev, sizeof(*arizona_gpio),
164 arizona_gpio->arizona = arizona;
165 arizona_gpio->gpio_chip = template_chip;
166 arizona_gpio->gpio_chip.parent = &pdev->dev;
167 #ifdef CONFIG_OF_GPIO
168 arizona_gpio->gpio_chip.of_node = arizona->dev->of_node;
171 switch (arizona->type) {
178 arizona_gpio->gpio_chip.ngpio = 5;
182 arizona_gpio->gpio_chip.ngpio = 2;
185 dev_err(&pdev->dev, "Unknown chip variant %d\n",
190 if (pdata && pdata->gpio_base)
191 arizona_gpio->gpio_chip.base = pdata->gpio_base;
193 arizona_gpio->gpio_chip.base = -1;
195 pm_runtime_enable(&pdev->dev);
197 ret = devm_gpiochip_add_data(&pdev->dev, &arizona_gpio->gpio_chip,
200 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
208 static struct platform_driver arizona_gpio_driver = {
209 .driver.name = "arizona-gpio",
210 .probe = arizona_gpio_probe,
213 module_platform_driver(arizona_gpio_driver);
215 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
216 MODULE_DESCRIPTION("GPIO interface for Arizona devices");
217 MODULE_LICENSE("GPL");
218 MODULE_ALIAS("platform:arizona-gpio");