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
wm8350_gpio_direction_in(struct gpio_chip * chip,unsigned offset)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
wm8350_gpio_get(struct gpio_chip * chip,unsigned offset)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
wm8350_gpio_set(struct gpio_chip * chip,unsigned offset,int value)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
wm8350_gpio_direction_out(struct gpio_chip * chip,unsigned offset,int value)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
wm8350_gpio_to_irq(struct gpio_chip * chip,unsigned offset)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 const 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
wm8350_gpio_probe(struct platform_device * pdev)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 = devm_gpiochip_add_data(&pdev->dev, &wm8350_gpio->gpio_chip,
129 wm8350_gpio);
130 if (ret < 0) {
131 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
132 return ret;
133 }
134
135 platform_set_drvdata(pdev, wm8350_gpio);
136
137 return ret;
138 }
139
140 static struct platform_driver wm8350_gpio_driver = {
141 .driver.name = "wm8350-gpio",
142 .probe = wm8350_gpio_probe,
143 };
144
wm8350_gpio_init(void)145 static int __init wm8350_gpio_init(void)
146 {
147 return platform_driver_register(&wm8350_gpio_driver);
148 }
149 subsys_initcall(wm8350_gpio_init);
150
wm8350_gpio_exit(void)151 static void __exit wm8350_gpio_exit(void)
152 {
153 platform_driver_unregister(&wm8350_gpio_driver);
154 }
155 module_exit(wm8350_gpio_exit);
156
157 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
158 MODULE_DESCRIPTION("GPIO interface for WM8350 PMICs");
159 MODULE_LICENSE("GPL");
160 MODULE_ALIAS("platform:wm8350-gpio");
161