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leds-max8997.c
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1 /*
2  * leds-max8997.c - LED class driver for MAX8997 LEDs.
3  *
4  * Copyright (C) 2011 Samsung Electronics
5  * Donggeun Kim <[email protected]>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  */
12 
13 #include <linux/module.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/workqueue.h>
17 #include <linux/leds.h>
18 #include <linux/mfd/max8997.h>
19 #include <linux/mfd/max8997-private.h>
20 #include <linux/platform_device.h>
21 
22 #define MAX8997_LED_FLASH_SHIFT 3
23 #define MAX8997_LED_FLASH_CUR_MASK 0xf8
24 #define MAX8997_LED_MOVIE_SHIFT 4
25 #define MAX8997_LED_MOVIE_CUR_MASK 0xf0
26 
27 #define MAX8997_LED_FLASH_MAX_BRIGHTNESS 0x1f
28 #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS 0xf
29 #define MAX8997_LED_NONE_MAX_BRIGHTNESS 0
30 
31 #define MAX8997_LED0_FLASH_MASK 0x1
32 #define MAX8997_LED0_FLASH_PIN_MASK 0x5
33 #define MAX8997_LED0_MOVIE_MASK 0x8
34 #define MAX8997_LED0_MOVIE_PIN_MASK 0x28
35 
36 #define MAX8997_LED1_FLASH_MASK 0x2
37 #define MAX8997_LED1_FLASH_PIN_MASK 0x6
38 #define MAX8997_LED1_MOVIE_MASK 0x10
39 #define MAX8997_LED1_MOVIE_PIN_MASK 0x30
40 
41 #define MAX8997_LED_BOOST_ENABLE_MASK (1 << 6)
42 
43 struct max8997_led {
44  struct max8997_dev *iodev;
45  struct led_classdev cdev;
46  bool enabled;
47  int id;
48  enum max8997_led_mode led_mode;
49  struct mutex mutex;
50 };
51 
52 static void max8997_led_set_mode(struct max8997_led *led,
53  enum max8997_led_mode mode)
54 {
55  int ret;
56  struct i2c_client *client = led->iodev->i2c;
57  u8 mask = 0, val;
58 
59  switch (mode) {
60  case MAX8997_FLASH_MODE:
61  mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
62  val = led->id ?
63  MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
64  led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
65  break;
66  case MAX8997_MOVIE_MODE:
67  mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
68  val = led->id ?
69  MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
70  led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
71  break;
72  case MAX8997_FLASH_PIN_CONTROL_MODE:
73  mask = MAX8997_LED1_FLASH_PIN_MASK |
74  MAX8997_LED0_FLASH_PIN_MASK;
75  val = led->id ?
76  MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
77  led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
78  break;
79  case MAX8997_MOVIE_PIN_CONTROL_MODE:
80  mask = MAX8997_LED1_MOVIE_PIN_MASK |
81  MAX8997_LED0_MOVIE_PIN_MASK;
82  val = led->id ?
83  MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
84  led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
85  break;
86  default:
87  led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
88  break;
89  }
90 
91  if (mask) {
92  ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
93  mask);
94  if (ret)
95  dev_err(led->iodev->dev,
96  "failed to update register(%d)\n", ret);
97  }
98 
99  led->led_mode = mode;
100 }
101 
102 static void max8997_led_enable(struct max8997_led *led, bool enable)
103 {
104  int ret;
105  struct i2c_client *client = led->iodev->i2c;
106  u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
107 
108  if (led->enabled == enable)
109  return;
110 
111  val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
112 
113  ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
114  if (ret)
115  dev_err(led->iodev->dev,
116  "failed to update register(%d)\n", ret);
117 
118  led->enabled = enable;
119 }
120 
121 static void max8997_led_set_current(struct max8997_led *led,
122  enum led_brightness value)
123 {
124  int ret;
125  struct i2c_client *client = led->iodev->i2c;
126  u8 val = 0, mask = 0, reg = 0;
127 
128  switch (led->led_mode) {
129  case MAX8997_FLASH_MODE:
130  case MAX8997_FLASH_PIN_CONTROL_MODE:
131  val = value << MAX8997_LED_FLASH_SHIFT;
132  mask = MAX8997_LED_FLASH_CUR_MASK;
133  reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
134  break;
135  case MAX8997_MOVIE_MODE:
136  case MAX8997_MOVIE_PIN_CONTROL_MODE:
137  val = value << MAX8997_LED_MOVIE_SHIFT;
138  mask = MAX8997_LED_MOVIE_CUR_MASK;
139  reg = MAX8997_REG_MOVIE_CUR;
140  break;
141  default:
142  break;
143  }
144 
145  if (mask) {
146  ret = max8997_update_reg(client, reg, val, mask);
147  if (ret)
148  dev_err(led->iodev->dev,
149  "failed to update register(%d)\n", ret);
150  }
151 }
152 
153 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
154  enum led_brightness value)
155 {
156  struct max8997_led *led =
157  container_of(led_cdev, struct max8997_led, cdev);
158 
159  if (value) {
160  max8997_led_set_current(led, value);
161  max8997_led_enable(led, true);
162  } else {
163  max8997_led_set_current(led, value);
164  max8997_led_enable(led, false);
165  }
166 }
167 
168 static ssize_t max8997_led_show_mode(struct device *dev,
169  struct device_attribute *attr, char *buf)
170 {
171  struct led_classdev *led_cdev = dev_get_drvdata(dev);
172  struct max8997_led *led =
173  container_of(led_cdev, struct max8997_led, cdev);
174  ssize_t ret = 0;
175 
176  mutex_lock(&led->mutex);
177 
178  switch (led->led_mode) {
179  case MAX8997_FLASH_MODE:
180  ret += sprintf(buf, "FLASH\n");
181  break;
182  case MAX8997_MOVIE_MODE:
183  ret += sprintf(buf, "MOVIE\n");
184  break;
185  case MAX8997_FLASH_PIN_CONTROL_MODE:
186  ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
187  break;
188  case MAX8997_MOVIE_PIN_CONTROL_MODE:
189  ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
190  break;
191  default:
192  ret += sprintf(buf, "NONE\n");
193  break;
194  }
195 
196  mutex_unlock(&led->mutex);
197 
198  return ret;
199 }
200 
201 static ssize_t max8997_led_store_mode(struct device *dev,
202  struct device_attribute *attr,
203  const char *buf, size_t size)
204 {
205  struct led_classdev *led_cdev = dev_get_drvdata(dev);
206  struct max8997_led *led =
207  container_of(led_cdev, struct max8997_led, cdev);
208  enum max8997_led_mode mode;
209 
210  mutex_lock(&led->mutex);
211 
212  if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
213  mode = MAX8997_FLASH_PIN_CONTROL_MODE;
214  else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
215  mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
216  else if (!strncmp(buf, "FLASH", 5))
217  mode = MAX8997_FLASH_MODE;
218  else if (!strncmp(buf, "MOVIE", 5))
219  mode = MAX8997_MOVIE_MODE;
220  else
221  mode = MAX8997_NONE;
222 
223  max8997_led_set_mode(led, mode);
224 
225  mutex_unlock(&led->mutex);
226 
227  return size;
228 }
229 
230 static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
231 
232 static int __devinit max8997_led_probe(struct platform_device *pdev)
233 {
234  struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
235  struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
236  struct max8997_led *led;
237  char name[20];
238  int ret = 0;
239 
240  if (pdata == NULL) {
241  dev_err(&pdev->dev, "no platform data\n");
242  return -ENODEV;
243  }
244 
245  led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
246  if (led == NULL)
247  return -ENOMEM;
248 
249  led->id = pdev->id;
250  snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
251 
252  led->cdev.name = name;
253  led->cdev.brightness_set = max8997_led_brightness_set;
254  led->cdev.flags |= LED_CORE_SUSPENDRESUME;
255  led->cdev.brightness = 0;
256  led->iodev = iodev;
257 
258  /* initialize mode and brightness according to platform_data */
259  if (pdata->led_pdata) {
260  u8 mode = 0, brightness = 0;
261 
262  mode = pdata->led_pdata->mode[led->id];
263  brightness = pdata->led_pdata->brightness[led->id];
264 
265  max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
266 
267  if (brightness > led->cdev.max_brightness)
268  brightness = led->cdev.max_brightness;
269  max8997_led_set_current(led, brightness);
270  led->cdev.brightness = brightness;
271  } else {
272  max8997_led_set_mode(led, MAX8997_NONE);
273  max8997_led_set_current(led, 0);
274  }
275 
276  mutex_init(&led->mutex);
277 
278  platform_set_drvdata(pdev, led);
279 
280  ret = led_classdev_register(&pdev->dev, &led->cdev);
281  if (ret < 0)
282  return ret;
283 
284  ret = device_create_file(led->cdev.dev, &dev_attr_mode);
285  if (ret != 0) {
286  dev_err(&pdev->dev,
287  "failed to create file: %d\n", ret);
288  led_classdev_unregister(&led->cdev);
289  return ret;
290  }
291 
292  return 0;
293 }
294 
295 static int __devexit max8997_led_remove(struct platform_device *pdev)
296 {
297  struct max8997_led *led = platform_get_drvdata(pdev);
298 
299  device_remove_file(led->cdev.dev, &dev_attr_mode);
300  led_classdev_unregister(&led->cdev);
301 
302  return 0;
303 }
304 
305 static struct platform_driver max8997_led_driver = {
306  .driver = {
307  .name = "max8997-led",
308  .owner = THIS_MODULE,
309  },
310  .probe = max8997_led_probe,
311  .remove = __devexit_p(max8997_led_remove),
312 };
313 
314 module_platform_driver(max8997_led_driver);
315 
316 MODULE_AUTHOR("Donggeun Kim <[email protected]>");
317 MODULE_DESCRIPTION("MAX8997 LED driver");
318 MODULE_LICENSE("GPL");
319 MODULE_ALIAS("platform:max8997-led");
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