diff options
Diffstat (limited to 'drivers/gpio/gpio-wm8994.c')
-rw-r--r-- | drivers/gpio/gpio-wm8994.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-wm8994.c b/drivers/gpio/gpio-wm8994.c new file mode 100644 index 00000000000..96198f3fab7 --- /dev/null +++ b/drivers/gpio/gpio-wm8994.c | |||
@@ -0,0 +1,242 @@ | |||
1 | /* | ||
2 | * gpiolib support for Wolfson WM8994 | ||
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/wm8994/core.h> | ||
24 | #include <linux/mfd/wm8994/pdata.h> | ||
25 | #include <linux/mfd/wm8994/gpio.h> | ||
26 | #include <linux/mfd/wm8994/registers.h> | ||
27 | |||
28 | struct wm8994_gpio { | ||
29 | struct wm8994 *wm8994; | ||
30 | struct gpio_chip gpio_chip; | ||
31 | }; | ||
32 | |||
33 | static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip) | ||
34 | { | ||
35 | return container_of(chip, struct wm8994_gpio, gpio_chip); | ||
36 | } | ||
37 | |||
38 | static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset) | ||
39 | { | ||
40 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
41 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
42 | |||
43 | switch (wm8994->type) { | ||
44 | case WM8958: | ||
45 | switch (offset) { | ||
46 | case 1: | ||
47 | case 2: | ||
48 | case 3: | ||
49 | case 4: | ||
50 | case 6: | ||
51 | return -EINVAL; | ||
52 | } | ||
53 | break; | ||
54 | default: | ||
55 | break; | ||
56 | } | ||
57 | |||
58 | return 0; | ||
59 | } | ||
60 | |||
61 | static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset) | ||
62 | { | ||
63 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
64 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
65 | |||
66 | return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, | ||
67 | WM8994_GPN_DIR, WM8994_GPN_DIR); | ||
68 | } | ||
69 | |||
70 | static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset) | ||
71 | { | ||
72 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
73 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
74 | int ret; | ||
75 | |||
76 | ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset); | ||
77 | if (ret < 0) | ||
78 | return ret; | ||
79 | |||
80 | if (ret & WM8994_GPN_LVL) | ||
81 | return 1; | ||
82 | else | ||
83 | return 0; | ||
84 | } | ||
85 | |||
86 | static int wm8994_gpio_direction_out(struct gpio_chip *chip, | ||
87 | unsigned offset, int value) | ||
88 | { | ||
89 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
90 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
91 | |||
92 | return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, | ||
93 | WM8994_GPN_DIR, 0); | ||
94 | } | ||
95 | |||
96 | static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value) | ||
97 | { | ||
98 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
99 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
100 | |||
101 | if (value) | ||
102 | value = WM8994_GPN_LVL; | ||
103 | |||
104 | wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value); | ||
105 | } | ||
106 | |||
107 | static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset) | ||
108 | { | ||
109 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
110 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
111 | |||
112 | if (!wm8994->irq_base) | ||
113 | return -EINVAL; | ||
114 | |||
115 | return wm8994->irq_base + offset; | ||
116 | } | ||
117 | |||
118 | |||
119 | #ifdef CONFIG_DEBUG_FS | ||
120 | static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) | ||
121 | { | ||
122 | struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip); | ||
123 | struct wm8994 *wm8994 = wm8994_gpio->wm8994; | ||
124 | int i; | ||
125 | |||
126 | for (i = 0; i < chip->ngpio; i++) { | ||
127 | int gpio = i + chip->base; | ||
128 | int reg; | ||
129 | const char *label; | ||
130 | |||
131 | /* We report the GPIO even if it's not requested since | ||
132 | * we're also reporting things like alternate | ||
133 | * functions which apply even when the GPIO is not in | ||
134 | * use as a GPIO. | ||
135 | */ | ||
136 | label = gpiochip_is_requested(chip, i); | ||
137 | if (!label) | ||
138 | label = "Unrequested"; | ||
139 | |||
140 | seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label); | ||
141 | |||
142 | reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i); | ||
143 | if (reg < 0) { | ||
144 | dev_err(wm8994->dev, | ||
145 | "GPIO control %d read failed: %d\n", | ||
146 | gpio, reg); | ||
147 | seq_printf(s, "\n"); | ||
148 | continue; | ||
149 | } | ||
150 | |||
151 | /* No decode yet; note that GPIO2 is special */ | ||
152 | seq_printf(s, "(%x)\n", reg); | ||
153 | } | ||
154 | } | ||
155 | #else | ||
156 | #define wm8994_gpio_dbg_show NULL | ||
157 | #endif | ||
158 | |||
159 | static struct gpio_chip template_chip = { | ||
160 | .label = "wm8994", | ||
161 | .owner = THIS_MODULE, | ||
162 | .request = wm8994_gpio_request, | ||
163 | .direction_input = wm8994_gpio_direction_in, | ||
164 | .get = wm8994_gpio_get, | ||
165 | .direction_output = wm8994_gpio_direction_out, | ||
166 | .set = wm8994_gpio_set, | ||
167 | .to_irq = wm8994_gpio_to_irq, | ||
168 | .dbg_show = wm8994_gpio_dbg_show, | ||
169 | .can_sleep = 1, | ||
170 | }; | ||
171 | |||
172 | static int __devinit wm8994_gpio_probe(struct platform_device *pdev) | ||
173 | { | ||
174 | struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); | ||
175 | struct wm8994_pdata *pdata = wm8994->dev->platform_data; | ||
176 | struct wm8994_gpio *wm8994_gpio; | ||
177 | int ret; | ||
178 | |||
179 | wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL); | ||
180 | if (wm8994_gpio == NULL) | ||
181 | return -ENOMEM; | ||
182 | |||
183 | wm8994_gpio->wm8994 = wm8994; | ||
184 | wm8994_gpio->gpio_chip = template_chip; | ||
185 | wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX; | ||
186 | wm8994_gpio->gpio_chip.dev = &pdev->dev; | ||
187 | if (pdata && pdata->gpio_base) | ||
188 | wm8994_gpio->gpio_chip.base = pdata->gpio_base; | ||
189 | else | ||
190 | wm8994_gpio->gpio_chip.base = -1; | ||
191 | |||
192 | ret = gpiochip_add(&wm8994_gpio->gpio_chip); | ||
193 | if (ret < 0) { | ||
194 | dev_err(&pdev->dev, "Could not register gpiochip, %d\n", | ||
195 | ret); | ||
196 | goto err; | ||
197 | } | ||
198 | |||
199 | platform_set_drvdata(pdev, wm8994_gpio); | ||
200 | |||
201 | return ret; | ||
202 | |||
203 | err: | ||
204 | kfree(wm8994_gpio); | ||
205 | return ret; | ||
206 | } | ||
207 | |||
208 | static int __devexit wm8994_gpio_remove(struct platform_device *pdev) | ||
209 | { | ||
210 | struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev); | ||
211 | int ret; | ||
212 | |||
213 | ret = gpiochip_remove(&wm8994_gpio->gpio_chip); | ||
214 | if (ret == 0) | ||
215 | kfree(wm8994_gpio); | ||
216 | |||
217 | return ret; | ||
218 | } | ||
219 | |||
220 | static struct platform_driver wm8994_gpio_driver = { | ||
221 | .driver.name = "wm8994-gpio", | ||
222 | .driver.owner = THIS_MODULE, | ||
223 | .probe = wm8994_gpio_probe, | ||
224 | .remove = __devexit_p(wm8994_gpio_remove), | ||
225 | }; | ||
226 | |||
227 | static int __init wm8994_gpio_init(void) | ||
228 | { | ||
229 | return platform_driver_register(&wm8994_gpio_driver); | ||
230 | } | ||
231 | subsys_initcall(wm8994_gpio_init); | ||
232 | |||
233 | static void __exit wm8994_gpio_exit(void) | ||
234 | { | ||
235 | platform_driver_unregister(&wm8994_gpio_driver); | ||
236 | } | ||
237 | module_exit(wm8994_gpio_exit); | ||
238 | |||
239 | MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); | ||
240 | MODULE_DESCRIPTION("GPIO interface for WM8994"); | ||
241 | MODULE_LICENSE("GPL"); | ||
242 | MODULE_ALIAS("platform:wm8994-gpio"); | ||