1 /*
2 * leds-max8997.c - LED class driver for MAX8997 LEDs.
3 *
4 * Copyright (C) 2011 Samsung Electronics
5 * Donggeun Kim <dg77.kim@samsung.com>
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
max8997_led_set_mode(struct max8997_led * led,enum max8997_led_mode mode)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
max8997_led_enable(struct max8997_led * led,bool enable)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
max8997_led_set_current(struct max8997_led * led,enum led_brightness value)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
max8997_led_brightness_set(struct led_classdev * led_cdev,enum led_brightness value)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
max8997_led_show_mode(struct device * dev,struct device_attribute * attr,char * buf)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
max8997_led_store_mode(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)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 struct attribute *max8997_attrs[] = {
233 &dev_attr_mode.attr,
234 NULL
235 };
236 ATTRIBUTE_GROUPS(max8997);
237
max8997_led_probe(struct platform_device * pdev)238 static int max8997_led_probe(struct platform_device *pdev)
239 {
240 struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
241 struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
242 struct max8997_led *led;
243 char name[20];
244 int ret = 0;
245
246 if (pdata == NULL) {
247 dev_err(&pdev->dev, "no platform data\n");
248 return -ENODEV;
249 }
250
251 led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
252 if (led == NULL)
253 return -ENOMEM;
254
255 led->id = pdev->id;
256 snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
257
258 led->cdev.name = name;
259 led->cdev.brightness_set = max8997_led_brightness_set;
260 led->cdev.flags |= LED_CORE_SUSPENDRESUME;
261 led->cdev.brightness = 0;
262 led->cdev.groups = max8997_groups;
263 led->iodev = iodev;
264
265 /* initialize mode and brightness according to platform_data */
266 if (pdata->led_pdata) {
267 u8 mode = 0, brightness = 0;
268
269 mode = pdata->led_pdata->mode[led->id];
270 brightness = pdata->led_pdata->brightness[led->id];
271
272 max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
273
274 if (brightness > led->cdev.max_brightness)
275 brightness = led->cdev.max_brightness;
276 max8997_led_set_current(led, brightness);
277 led->cdev.brightness = brightness;
278 } else {
279 max8997_led_set_mode(led, MAX8997_NONE);
280 max8997_led_set_current(led, 0);
281 }
282
283 mutex_init(&led->mutex);
284
285 platform_set_drvdata(pdev, led);
286
287 ret = led_classdev_register(&pdev->dev, &led->cdev);
288 if (ret < 0)
289 return ret;
290
291 return 0;
292 }
293
max8997_led_remove(struct platform_device * pdev)294 static int max8997_led_remove(struct platform_device *pdev)
295 {
296 struct max8997_led *led = platform_get_drvdata(pdev);
297
298 led_classdev_unregister(&led->cdev);
299
300 return 0;
301 }
302
303 static struct platform_driver max8997_led_driver = {
304 .driver = {
305 .name = "max8997-led",
306 },
307 .probe = max8997_led_probe,
308 .remove = max8997_led_remove,
309 };
310
311 module_platform_driver(max8997_led_driver);
312
313 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
314 MODULE_DESCRIPTION("MAX8997 LED driver");
315 MODULE_LICENSE("GPL");
316 MODULE_ALIAS("platform:max8997-led");
317