blob: 2ac9a16d3daa9723dd9f2c34b6d774c62392dd58 [file] [log] [blame]
Mark Brown2955c302010-01-29 18:20:30 +00001/*
2 * wm8994-gpio.c -- 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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090016#include <linux/slab.h>
Mark Brown2955c302010-01-29 18:20:30 +000017#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
28struct wm8994_gpio {
29 struct wm8994 *wm8994;
30 struct gpio_chip gpio_chip;
31};
32
33static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip)
34{
35 return container_of(chip, struct wm8994_gpio, gpio_chip);
36}
37
38static int wm8994_gpio_direction_in(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 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
44 WM8994_GPN_DIR, WM8994_GPN_DIR);
45}
46
47static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
48{
49 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
50 struct wm8994 *wm8994 = wm8994_gpio->wm8994;
51 int ret;
52
53 ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
54 if (ret < 0)
55 return ret;
56
57 if (ret & WM8994_GPN_LVL)
58 return 1;
59 else
60 return 0;
61}
62
63static int wm8994_gpio_direction_out(struct gpio_chip *chip,
64 unsigned offset, int value)
65{
66 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
67 struct wm8994 *wm8994 = wm8994_gpio->wm8994;
68
69 return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
70 WM8994_GPN_DIR, 0);
71}
72
73static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
74{
75 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
76 struct wm8994 *wm8994 = wm8994_gpio->wm8994;
77
78 if (value)
79 value = WM8994_GPN_LVL;
80
81 wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
82}
83
Mark Brownddf438c2010-04-02 14:51:59 +010084static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
85{
86 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
87 struct wm8994 *wm8994 = wm8994_gpio->wm8994;
88
89 if (!wm8994->irq_base)
90 return -EINVAL;
91
92 return wm8994->irq_base + offset;
93}
94
95
Mark Brown2955c302010-01-29 18:20:30 +000096#ifdef CONFIG_DEBUG_FS
97static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
98{
99 struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
100 struct wm8994 *wm8994 = wm8994_gpio->wm8994;
101 int i;
102
103 for (i = 0; i < chip->ngpio; i++) {
104 int gpio = i + chip->base;
105 int reg;
106 const char *label;
107
108 /* We report the GPIO even if it's not requested since
109 * we're also reporting things like alternate
110 * functions which apply even when the GPIO is not in
111 * use as a GPIO.
112 */
113 label = gpiochip_is_requested(chip, i);
114 if (!label)
115 label = "Unrequested";
116
117 seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
118
119 reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
120 if (reg < 0) {
121 dev_err(wm8994->dev,
122 "GPIO control %d read failed: %d\n",
123 gpio, reg);
124 seq_printf(s, "\n");
125 continue;
126 }
127
128 /* No decode yet; note that GPIO2 is special */
129 seq_printf(s, "(%x)\n", reg);
130 }
131}
132#else
133#define wm8994_gpio_dbg_show NULL
134#endif
135
136static struct gpio_chip template_chip = {
137 .label = "wm8994",
138 .owner = THIS_MODULE,
139 .direction_input = wm8994_gpio_direction_in,
140 .get = wm8994_gpio_get,
141 .direction_output = wm8994_gpio_direction_out,
142 .set = wm8994_gpio_set,
143 .dbg_show = wm8994_gpio_dbg_show,
144 .can_sleep = 1,
145};
146
147static int __devinit wm8994_gpio_probe(struct platform_device *pdev)
148{
149 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
150 struct wm8994_pdata *pdata = wm8994->dev->platform_data;
151 struct wm8994_gpio *wm8994_gpio;
152 int ret;
153
154 wm8994_gpio = kzalloc(sizeof(*wm8994_gpio), GFP_KERNEL);
155 if (wm8994_gpio == NULL)
156 return -ENOMEM;
157
158 wm8994_gpio->wm8994 = wm8994;
159 wm8994_gpio->gpio_chip = template_chip;
160 wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
161 wm8994_gpio->gpio_chip.dev = &pdev->dev;
162 if (pdata && pdata->gpio_base)
163 wm8994_gpio->gpio_chip.base = pdata->gpio_base;
164 else
165 wm8994_gpio->gpio_chip.base = -1;
166
167 ret = gpiochip_add(&wm8994_gpio->gpio_chip);
168 if (ret < 0) {
169 dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
170 ret);
171 goto err;
172 }
173
174 platform_set_drvdata(pdev, wm8994_gpio);
175
176 return ret;
177
178err:
179 kfree(wm8994_gpio);
180 return ret;
181}
182
183static int __devexit wm8994_gpio_remove(struct platform_device *pdev)
184{
185 struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev);
186 int ret;
187
188 ret = gpiochip_remove(&wm8994_gpio->gpio_chip);
189 if (ret == 0)
190 kfree(wm8994_gpio);
191
192 return ret;
193}
194
195static struct platform_driver wm8994_gpio_driver = {
196 .driver.name = "wm8994-gpio",
197 .driver.owner = THIS_MODULE,
198 .probe = wm8994_gpio_probe,
199 .remove = __devexit_p(wm8994_gpio_remove),
200};
201
202static int __init wm8994_gpio_init(void)
203{
204 return platform_driver_register(&wm8994_gpio_driver);
205}
206subsys_initcall(wm8994_gpio_init);
207
208static void __exit wm8994_gpio_exit(void)
209{
210 platform_driver_unregister(&wm8994_gpio_driver);
211}
212module_exit(wm8994_gpio_exit);
213
214MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
215MODULE_DESCRIPTION("GPIO interface for WM8994");
216MODULE_LICENSE("GPL");
217MODULE_ALIAS("platform:wm8994-gpio");