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gpio-wm8994.c
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1 /*
2  * gpiolib support for Wolfson WM8994
3  *
4  * Copyright 2009 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <[email protected]>
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 #include <linux/regmap.h>
23 
24 #include <linux/mfd/wm8994/core.h>
25 #include <linux/mfd/wm8994/pdata.h>
26 #include <linux/mfd/wm8994/gpio.h>
27 #include <linux/mfd/wm8994/registers.h>
28 
29 struct wm8994_gpio {
30  struct wm8994 *wm8994;
31  struct gpio_chip gpio_chip;
32 };
33 
34 static inline struct wm8994_gpio *to_wm8994_gpio(struct gpio_chip *chip)
35 {
36  return container_of(chip, struct wm8994_gpio, gpio_chip);
37 }
38 
39 static int wm8994_gpio_request(struct gpio_chip *chip, unsigned offset)
40 {
41  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
42  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
43 
44  switch (wm8994->type) {
45  case WM8958:
46  switch (offset) {
47  case 1:
48  case 2:
49  case 3:
50  case 4:
51  case 6:
52  return -EINVAL;
53  }
54  break;
55  default:
56  break;
57  }
58 
59  return 0;
60 }
61 
62 static int wm8994_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
63 {
64  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
65  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
66 
67  return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
68  WM8994_GPN_DIR, WM8994_GPN_DIR);
69 }
70 
71 static int wm8994_gpio_get(struct gpio_chip *chip, unsigned offset)
72 {
73  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
74  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
75  int ret;
76 
77  ret = wm8994_reg_read(wm8994, WM8994_GPIO_1 + offset);
78  if (ret < 0)
79  return ret;
80 
81  if (ret & WM8994_GPN_LVL)
82  return 1;
83  else
84  return 0;
85 }
86 
87 static int wm8994_gpio_direction_out(struct gpio_chip *chip,
88  unsigned offset, int value)
89 {
90  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
91  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
92 
93  if (value)
94  value = WM8994_GPN_LVL;
95 
96  return wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset,
97  WM8994_GPN_DIR | WM8994_GPN_LVL, value);
98 }
99 
100 static void wm8994_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
101 {
102  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
103  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
104 
105  if (value)
106  value = WM8994_GPN_LVL;
107 
108  wm8994_set_bits(wm8994, WM8994_GPIO_1 + offset, WM8994_GPN_LVL, value);
109 }
110 
111 static int wm8994_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
112 {
113  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
114  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
115 
116  return regmap_irq_get_virq(wm8994->irq_data, offset);
117 }
118 
119 
120 #ifdef CONFIG_DEBUG_FS
121 static const char *wm8994_gpio_fn(u16 fn)
122 {
123  switch (fn) {
124  case WM8994_GP_FN_PIN_SPECIFIC:
125  return "pin-specific";
126  case WM8994_GP_FN_GPIO:
127  return "GPIO";
128  case WM8994_GP_FN_SDOUT:
129  return "SDOUT";
130  case WM8994_GP_FN_IRQ:
131  return "IRQ";
132  case WM8994_GP_FN_TEMPERATURE:
133  return "Temperature";
134  case WM8994_GP_FN_MICBIAS1_DET:
135  return "MICBIAS1 detect";
136  case WM8994_GP_FN_MICBIAS1_SHORT:
137  return "MICBIAS1 short";
138  case WM8994_GP_FN_MICBIAS2_DET:
139  return "MICBIAS2 detect";
140  case WM8994_GP_FN_MICBIAS2_SHORT:
141  return "MICBIAS2 short";
142  case WM8994_GP_FN_FLL1_LOCK:
143  return "FLL1 lock";
144  case WM8994_GP_FN_FLL2_LOCK:
145  return "FLL2 lock";
146  case WM8994_GP_FN_SRC1_LOCK:
147  return "SRC1 lock";
148  case WM8994_GP_FN_SRC2_LOCK:
149  return "SRC2 lock";
150  case WM8994_GP_FN_DRC1_ACT:
151  return "DRC1 activity";
152  case WM8994_GP_FN_DRC2_ACT:
153  return "DRC2 activity";
154  case WM8994_GP_FN_DRC3_ACT:
155  return "DRC3 activity";
156  case WM8994_GP_FN_WSEQ_STATUS:
157  return "Write sequencer";
158  case WM8994_GP_FN_FIFO_ERROR:
159  return "FIFO error";
160  case WM8994_GP_FN_OPCLK:
161  return "OPCLK";
162  case WM8994_GP_FN_THW:
163  return "Thermal warning";
164  case WM8994_GP_FN_DCS_DONE:
165  return "DC servo";
166  case WM8994_GP_FN_FLL1_OUT:
167  return "FLL1 output";
168  case WM8994_GP_FN_FLL2_OUT:
169  return "FLL1 output";
170  default:
171  return "Unknown";
172  }
173 }
174 
175 static void wm8994_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
176 {
177  struct wm8994_gpio *wm8994_gpio = to_wm8994_gpio(chip);
178  struct wm8994 *wm8994 = wm8994_gpio->wm8994;
179  int i;
180 
181  for (i = 0; i < chip->ngpio; i++) {
182  int gpio = i + chip->base;
183  int reg;
184  const char *label;
185 
186  /* We report the GPIO even if it's not requested since
187  * we're also reporting things like alternate
188  * functions which apply even when the GPIO is not in
189  * use as a GPIO.
190  */
191  label = gpiochip_is_requested(chip, i);
192  if (!label)
193  label = "Unrequested";
194 
195  seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
196 
197  reg = wm8994_reg_read(wm8994, WM8994_GPIO_1 + i);
198  if (reg < 0) {
199  dev_err(wm8994->dev,
200  "GPIO control %d read failed: %d\n",
201  gpio, reg);
202  seq_printf(s, "\n");
203  continue;
204  }
205 
206  if (reg & WM8994_GPN_DIR)
207  seq_printf(s, "in ");
208  else
209  seq_printf(s, "out ");
210 
211  if (reg & WM8994_GPN_PU)
212  seq_printf(s, "pull up ");
213 
214  if (reg & WM8994_GPN_PD)
215  seq_printf(s, "pull down ");
216 
217  if (reg & WM8994_GPN_POL)
218  seq_printf(s, "inverted ");
219  else
220  seq_printf(s, "noninverted ");
221 
222  if (reg & WM8994_GPN_OP_CFG)
223  seq_printf(s, "open drain ");
224  else
225  seq_printf(s, "CMOS ");
226 
227  seq_printf(s, "%s (%x)\n",
228  wm8994_gpio_fn(reg & WM8994_GPN_FN_MASK), reg);
229  }
230 }
231 #else
232 #define wm8994_gpio_dbg_show NULL
233 #endif
234 
235 static struct gpio_chip template_chip = {
236  .label = "wm8994",
237  .owner = THIS_MODULE,
238  .request = wm8994_gpio_request,
239  .direction_input = wm8994_gpio_direction_in,
240  .get = wm8994_gpio_get,
241  .direction_output = wm8994_gpio_direction_out,
242  .set = wm8994_gpio_set,
243  .to_irq = wm8994_gpio_to_irq,
244  .dbg_show = wm8994_gpio_dbg_show,
245  .can_sleep = 1,
246 };
247 
248 static int __devinit wm8994_gpio_probe(struct platform_device *pdev)
249 {
250  struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
251  struct wm8994_pdata *pdata = wm8994->dev->platform_data;
252  struct wm8994_gpio *wm8994_gpio;
253  int ret;
254 
255  wm8994_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm8994_gpio),
256  GFP_KERNEL);
257  if (wm8994_gpio == NULL)
258  return -ENOMEM;
259 
260  wm8994_gpio->wm8994 = wm8994;
261  wm8994_gpio->gpio_chip = template_chip;
262  wm8994_gpio->gpio_chip.ngpio = WM8994_GPIO_MAX;
263  wm8994_gpio->gpio_chip.dev = &pdev->dev;
264  if (pdata && pdata->gpio_base)
265  wm8994_gpio->gpio_chip.base = pdata->gpio_base;
266  else
267  wm8994_gpio->gpio_chip.base = -1;
268 
269  ret = gpiochip_add(&wm8994_gpio->gpio_chip);
270  if (ret < 0) {
271  dev_err(&pdev->dev, "Could not register gpiochip, %d\n",
272  ret);
273  goto err;
274  }
275 
276  platform_set_drvdata(pdev, wm8994_gpio);
277 
278  return ret;
279 
280 err:
281  return ret;
282 }
283 
284 static int __devexit wm8994_gpio_remove(struct platform_device *pdev)
285 {
286  struct wm8994_gpio *wm8994_gpio = platform_get_drvdata(pdev);
287 
288  return gpiochip_remove(&wm8994_gpio->gpio_chip);
289 }
290 
291 static struct platform_driver wm8994_gpio_driver = {
292  .driver.name = "wm8994-gpio",
293  .driver.owner = THIS_MODULE,
294  .probe = wm8994_gpio_probe,
295  .remove = __devexit_p(wm8994_gpio_remove),
296 };
297 
298 static int __init wm8994_gpio_init(void)
299 {
300  return platform_driver_register(&wm8994_gpio_driver);
301 }
302 subsys_initcall(wm8994_gpio_init);
303 
304 static void __exit wm8994_gpio_exit(void)
305 {
306  platform_driver_unregister(&wm8994_gpio_driver);
307 }
308 module_exit(wm8994_gpio_exit);
309 
310 MODULE_AUTHOR("Mark Brown <[email protected]>");
311 MODULE_DESCRIPTION("GPIO interface for WM8994");
312 MODULE_LICENSE("GPL");
313 MODULE_ALIAS("platform:wm8994-gpio");
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