xref: /linux/drivers/gpio/gpio-wm8350.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * gpiolib support for Wolfson WM835x PMICs
3  *
4  * Copyright 2009 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/mfd/core.h>
20 #include <linux/platform_device.h>
21 #include <linux/seq_file.h>
22 
23 #include <linux/mfd/wm8350/core.h>
24 #include <linux/mfd/wm8350/gpio.h>
25 
26 struct wm8350_gpio_data {
27 	struct wm8350 *wm8350;
28 	struct gpio_chip gpio_chip;
29 };
30 
31 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
32 {
33 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
34 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
35 
36 	return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
37 			       1 << offset);
38 }
39 
40 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
41 {
42 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
43 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
44 	int ret;
45 
46 	ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
47 	if (ret < 0)
48 		return ret;
49 
50 	if (ret & (1 << offset))
51 		return 1;
52 	else
53 		return 0;
54 }
55 
56 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
57 {
58 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
59 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
60 
61 	if (value)
62 		wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
63 	else
64 		wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
65 }
66 
67 static int wm8350_gpio_direction_out(struct gpio_chip *chip,
68 				     unsigned offset, int value)
69 {
70 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
71 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
72 	int ret;
73 
74 	ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
75 				1 << offset);
76 	if (ret < 0)
77 		return ret;
78 
79 	/* Don't have an atomic direction/value setup */
80 	wm8350_gpio_set(chip, offset, value);
81 
82 	return 0;
83 }
84 
85 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
86 {
87 	struct wm8350_gpio_data *wm8350_gpio = gpiochip_get_data(chip);
88 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
89 
90 	if (!wm8350->irq_base)
91 		return -EINVAL;
92 
93 	return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
94 }
95 
96 static struct gpio_chip template_chip = {
97 	.label			= "wm8350",
98 	.owner			= THIS_MODULE,
99 	.direction_input	= wm8350_gpio_direction_in,
100 	.get			= wm8350_gpio_get,
101 	.direction_output	= wm8350_gpio_direction_out,
102 	.set			= wm8350_gpio_set,
103 	.to_irq			= wm8350_gpio_to_irq,
104 	.can_sleep		= true,
105 };
106 
107 static int wm8350_gpio_probe(struct platform_device *pdev)
108 {
109 	struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
110 	struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
111 	struct wm8350_gpio_data *wm8350_gpio;
112 	int ret;
113 
114 	wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
115 				   GFP_KERNEL);
116 	if (wm8350_gpio == NULL)
117 		return -ENOMEM;
118 
119 	wm8350_gpio->wm8350 = wm8350;
120 	wm8350_gpio->gpio_chip = template_chip;
121 	wm8350_gpio->gpio_chip.ngpio = 13;
122 	wm8350_gpio->gpio_chip.parent = &pdev->dev;
123 	if (pdata && pdata->gpio_base)
124 		wm8350_gpio->gpio_chip.base = pdata->gpio_base;
125 	else
126 		wm8350_gpio->gpio_chip.base = -1;
127 
128 	ret = gpiochip_add_data(&wm8350_gpio->gpio_chip, wm8350_gpio);
129 	if (ret < 0) {
130 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
131 		return ret;
132 	}
133 
134 	platform_set_drvdata(pdev, wm8350_gpio);
135 
136 	return ret;
137 }
138 
139 static int wm8350_gpio_remove(struct platform_device *pdev)
140 {
141 	struct wm8350_gpio_data *wm8350_gpio = platform_get_drvdata(pdev);
142 
143 	gpiochip_remove(&wm8350_gpio->gpio_chip);
144 	return 0;
145 }
146 
147 static struct platform_driver wm8350_gpio_driver = {
148 	.driver.name	= "wm8350-gpio",
149 	.driver.owner	= THIS_MODULE,
150 	.probe		= wm8350_gpio_probe,
151 	.remove		= wm8350_gpio_remove,
152 };
153 
154 static int __init wm8350_gpio_init(void)
155 {
156 	return platform_driver_register(&wm8350_gpio_driver);
157 }
158 subsys_initcall(wm8350_gpio_init);
159 
160 static void __exit wm8350_gpio_exit(void)
161 {
162 	platform_driver_unregister(&wm8350_gpio_driver);
163 }
164 module_exit(wm8350_gpio_exit);
165 
166 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
167 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
168 MODULE_LICENSE("GPL");
169 MODULE_ALIAS("platform:wm8350-gpio");
170