xref: /openbmc/linux/drivers/gpio/gpio-wm8350.c (revision 9cfc5c90)
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 inline struct wm8350_gpio_data *to_wm8350_gpio(struct gpio_chip *chip)
32 {
33 	return container_of(chip, struct wm8350_gpio_data, gpio_chip);
34 }
35 
36 static int wm8350_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
37 {
38 	struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip);
39 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
40 
41 	return wm8350_set_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
42 			       1 << offset);
43 }
44 
45 static int wm8350_gpio_get(struct gpio_chip *chip, unsigned offset)
46 {
47 	struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip);
48 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
49 	int ret;
50 
51 	ret = wm8350_reg_read(wm8350, WM8350_GPIO_LEVEL);
52 	if (ret < 0)
53 		return ret;
54 
55 	if (ret & (1 << offset))
56 		return 1;
57 	else
58 		return 0;
59 }
60 
61 static void wm8350_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
62 {
63 	struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip);
64 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
65 
66 	if (value)
67 		wm8350_set_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
68 	else
69 		wm8350_clear_bits(wm8350, WM8350_GPIO_LEVEL, 1 << offset);
70 }
71 
72 static int wm8350_gpio_direction_out(struct gpio_chip *chip,
73 				     unsigned offset, int value)
74 {
75 	struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip);
76 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
77 	int ret;
78 
79 	ret = wm8350_clear_bits(wm8350, WM8350_GPIO_CONFIGURATION_I_O,
80 				1 << offset);
81 	if (ret < 0)
82 		return ret;
83 
84 	/* Don't have an atomic direction/value setup */
85 	wm8350_gpio_set(chip, offset, value);
86 
87 	return 0;
88 }
89 
90 static int wm8350_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
91 {
92 	struct wm8350_gpio_data *wm8350_gpio = to_wm8350_gpio(chip);
93 	struct wm8350 *wm8350 = wm8350_gpio->wm8350;
94 
95 	if (!wm8350->irq_base)
96 		return -EINVAL;
97 
98 	return wm8350->irq_base + WM8350_IRQ_GPIO(offset);
99 }
100 
101 static struct gpio_chip template_chip = {
102 	.label			= "wm8350",
103 	.owner			= THIS_MODULE,
104 	.direction_input	= wm8350_gpio_direction_in,
105 	.get			= wm8350_gpio_get,
106 	.direction_output	= wm8350_gpio_direction_out,
107 	.set			= wm8350_gpio_set,
108 	.to_irq			= wm8350_gpio_to_irq,
109 	.can_sleep		= true,
110 };
111 
112 static int wm8350_gpio_probe(struct platform_device *pdev)
113 {
114 	struct wm8350 *wm8350 = dev_get_drvdata(pdev->dev.parent);
115 	struct wm8350_platform_data *pdata = dev_get_platdata(wm8350->dev);
116 	struct wm8350_gpio_data *wm8350_gpio;
117 	int ret;
118 
119 	wm8350_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8350_gpio),
120 				   GFP_KERNEL);
121 	if (wm8350_gpio == NULL)
122 		return -ENOMEM;
123 
124 	wm8350_gpio->wm8350 = wm8350;
125 	wm8350_gpio->gpio_chip = template_chip;
126 	wm8350_gpio->gpio_chip.ngpio = 13;
127 	wm8350_gpio->gpio_chip.dev = &pdev->dev;
128 	if (pdata && pdata->gpio_base)
129 		wm8350_gpio->gpio_chip.base = pdata->gpio_base;
130 	else
131 		wm8350_gpio->gpio_chip.base = -1;
132 
133 	ret = gpiochip_add(&wm8350_gpio->gpio_chip);
134 	if (ret < 0) {
135 		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
136 		return ret;
137 	}
138 
139 	platform_set_drvdata(pdev, wm8350_gpio);
140 
141 	return ret;
142 }
143 
144 static int wm8350_gpio_remove(struct platform_device *pdev)
145 {
146 	struct wm8350_gpio_data *wm8350_gpio = platform_get_drvdata(pdev);
147 
148 	gpiochip_remove(&wm8350_gpio->gpio_chip);
149 	return 0;
150 }
151 
152 static struct platform_driver wm8350_gpio_driver = {
153 	.driver.name	= "wm8350-gpio",
154 	.driver.owner	= THIS_MODULE,
155 	.probe		= wm8350_gpio_probe,
156 	.remove		= wm8350_gpio_remove,
157 };
158 
159 static int __init wm8350_gpio_init(void)
160 {
161 	return platform_driver_register(&wm8350_gpio_driver);
162 }
163 subsys_initcall(wm8350_gpio_init);
164 
165 static void __exit wm8350_gpio_exit(void)
166 {
167 	platform_driver_unregister(&wm8350_gpio_driver);
168 }
169 module_exit(wm8350_gpio_exit);
170 
171 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
172 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
173 MODULE_LICENSE("GPL");
174 MODULE_ALIAS("platform:wm8350-gpio");
175