xref: /linux/drivers/leds/leds-max8997.c (revision 681e4a5e13c1c8315694eb4f44e0cdd84c9082d2)
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 
52 static void max8997_led_clear_mode(struct max8997_led *led,
53 			enum max8997_led_mode mode)
54 {
55 	struct i2c_client *client = led->iodev->i2c;
56 	u8 val = 0, mask = 0;
57 	int ret;
58 
59 	switch (mode) {
60 	case MAX8997_FLASH_MODE:
61 		mask = led->id ?
62 		      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
63 		break;
64 	case MAX8997_MOVIE_MODE:
65 		mask = led->id ?
66 		      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
67 		break;
68 	case MAX8997_FLASH_PIN_CONTROL_MODE:
69 		mask = led->id ?
70 		      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
71 		break;
72 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
73 		mask = led->id ?
74 		      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
75 		break;
76 	default:
77 		break;
78 	}
79 
80 	if (mask) {
81 		ret = max8997_update_reg(client,
82 				MAX8997_REG_LEN_CNTL, val, mask);
83 		if (ret)
84 			dev_err(led->iodev->dev,
85 				"failed to update register(%d)\n", ret);
86 	}
87 }
88 
89 static void max8997_led_set_mode(struct max8997_led *led,
90 			enum max8997_led_mode mode)
91 {
92 	int ret;
93 	struct i2c_client *client = led->iodev->i2c;
94 	u8 mask = 0;
95 
96 	/* First, clear the previous mode */
97 	max8997_led_clear_mode(led, led->led_mode);
98 
99 	switch (mode) {
100 	case MAX8997_FLASH_MODE:
101 		mask = led->id ?
102 		      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
103 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
104 		break;
105 	case MAX8997_MOVIE_MODE:
106 		mask = led->id ?
107 		      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
108 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
109 		break;
110 	case MAX8997_FLASH_PIN_CONTROL_MODE:
111 		mask = led->id ?
112 		      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
113 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
114 		break;
115 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
116 		mask = led->id ?
117 		      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
118 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
119 		break;
120 	default:
121 		led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
122 		break;
123 	}
124 
125 	if (mask) {
126 		ret = max8997_update_reg(client,
127 				MAX8997_REG_LEN_CNTL, mask, mask);
128 		if (ret)
129 			dev_err(led->iodev->dev,
130 				"failed to update register(%d)\n", ret);
131 	}
132 
133 	led->led_mode = mode;
134 }
135 
136 static void max8997_led_enable(struct max8997_led *led, bool enable)
137 {
138 	int ret;
139 	struct i2c_client *client = led->iodev->i2c;
140 	u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
141 
142 	if (led->enabled == enable)
143 		return;
144 
145 	val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
146 
147 	ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
148 	if (ret)
149 		dev_err(led->iodev->dev,
150 			"failed to update register(%d)\n", ret);
151 
152 	led->enabled = enable;
153 }
154 
155 static void max8997_led_set_current(struct max8997_led *led,
156 				enum led_brightness value)
157 {
158 	int ret;
159 	struct i2c_client *client = led->iodev->i2c;
160 	u8 val = 0, mask = 0, reg = 0;
161 
162 	switch (led->led_mode) {
163 	case MAX8997_FLASH_MODE:
164 	case MAX8997_FLASH_PIN_CONTROL_MODE:
165 		val = value << MAX8997_LED_FLASH_SHIFT;
166 		mask = MAX8997_LED_FLASH_CUR_MASK;
167 		reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
168 		break;
169 	case MAX8997_MOVIE_MODE:
170 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
171 		val = value << MAX8997_LED_MOVIE_SHIFT;
172 		mask = MAX8997_LED_MOVIE_CUR_MASK;
173 		reg = MAX8997_REG_MOVIE_CUR;
174 		break;
175 	default:
176 		break;
177 	}
178 
179 	if (mask) {
180 		ret = max8997_update_reg(client, reg, val, mask);
181 		if (ret)
182 			dev_err(led->iodev->dev,
183 				"failed to update register(%d)\n", ret);
184 	}
185 }
186 
187 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
188 				enum led_brightness value)
189 {
190 	struct max8997_led *led =
191 			container_of(led_cdev, struct max8997_led, cdev);
192 
193 	if (value) {
194 		max8997_led_set_current(led, value);
195 		max8997_led_enable(led, true);
196 	} else {
197 		max8997_led_set_current(led, value);
198 		max8997_led_enable(led, false);
199 	}
200 }
201 
202 static ssize_t max8997_led_show_mode(struct device *dev,
203 				struct device_attribute *attr, char *buf)
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 	ssize_t ret = 0;
209 
210 	mutex_lock(&led->mutex);
211 
212 	switch (led->led_mode) {
213 	case MAX8997_FLASH_MODE:
214 		ret += sprintf(buf, "FLASH\n");
215 		break;
216 	case MAX8997_MOVIE_MODE:
217 		ret += sprintf(buf, "MOVIE\n");
218 		break;
219 	case MAX8997_FLASH_PIN_CONTROL_MODE:
220 		ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
221 		break;
222 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
223 		ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
224 		break;
225 	default:
226 		ret += sprintf(buf, "NONE\n");
227 		break;
228 	}
229 
230 	mutex_unlock(&led->mutex);
231 
232 	return ret;
233 }
234 
235 static ssize_t max8997_led_store_mode(struct device *dev,
236 				struct device_attribute *attr,
237 				const char *buf, size_t size)
238 {
239 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
240 	struct max8997_led *led =
241 			container_of(led_cdev, struct max8997_led, cdev);
242 	enum max8997_led_mode mode;
243 
244 	mutex_lock(&led->mutex);
245 
246 	if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
247 		mode = MAX8997_FLASH_PIN_CONTROL_MODE;
248 	else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
249 		mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
250 	else if (!strncmp(buf, "FLASH", 5))
251 		mode = MAX8997_FLASH_MODE;
252 	else if (!strncmp(buf, "MOVIE", 5))
253 		mode = MAX8997_MOVIE_MODE;
254 	else
255 		mode = MAX8997_NONE;
256 
257 	max8997_led_set_mode(led, mode);
258 
259 	mutex_unlock(&led->mutex);
260 
261 	return size;
262 }
263 
264 static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
265 
266 static int __devinit max8997_led_probe(struct platform_device *pdev)
267 {
268 	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
269 	struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
270 	struct max8997_led *led;
271 	char name[20];
272 	int ret = 0;
273 
274 	if (pdata == NULL) {
275 		dev_err(&pdev->dev, "no platform data\n");
276 		return -ENODEV;
277 	}
278 
279 	led = kzalloc(sizeof(*led), GFP_KERNEL);
280 	if (led == NULL) {
281 		ret = -ENOMEM;
282 		goto err_mem;
283 	}
284 
285 	led->id = pdev->id;
286 	snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
287 
288 	led->cdev.name = name;
289 	led->cdev.brightness_set = max8997_led_brightness_set;
290 	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
291 	led->cdev.brightness = 0;
292 	led->iodev = iodev;
293 
294 	/* initialize mode and brightness according to platform_data */
295 	if (pdata->led_pdata) {
296 		u8 mode = 0, brightness = 0;
297 
298 		mode = pdata->led_pdata->mode[led->id];
299 		brightness = pdata->led_pdata->brightness[led->id];
300 
301 		max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
302 
303 		if (brightness > led->cdev.max_brightness)
304 			brightness = led->cdev.max_brightness;
305 		max8997_led_set_current(led, brightness);
306 		led->cdev.brightness = brightness;
307 	} else {
308 		max8997_led_set_mode(led, MAX8997_NONE);
309 		max8997_led_set_current(led, 0);
310 	}
311 
312 	mutex_init(&led->mutex);
313 
314 	platform_set_drvdata(pdev, led);
315 
316 	ret = led_classdev_register(&pdev->dev, &led->cdev);
317 	if (ret < 0)
318 		goto err_led;
319 
320 	ret = device_create_file(led->cdev.dev, &dev_attr_mode);
321 	if (ret != 0) {
322 		dev_err(&pdev->dev,
323 			"failed to create file: %d\n", ret);
324 		goto err_file;
325 	}
326 
327 	return 0;
328 
329 err_file:
330 	led_classdev_unregister(&led->cdev);
331 err_led:
332 	kfree(led);
333 err_mem:
334 	return ret;
335 }
336 
337 static int __devexit max8997_led_remove(struct platform_device *pdev)
338 {
339 	struct max8997_led *led = platform_get_drvdata(pdev);
340 
341 	device_remove_file(led->cdev.dev, &dev_attr_mode);
342 	led_classdev_unregister(&led->cdev);
343 	kfree(led);
344 
345 	return 0;
346 }
347 
348 static struct platform_driver max8997_led_driver = {
349 	.driver = {
350 		.name  = "max8997-led",
351 		.owner = THIS_MODULE,
352 	},
353 	.probe  = max8997_led_probe,
354 	.remove = __devexit_p(max8997_led_remove),
355 };
356 
357 static int __init max8997_led_init(void)
358 {
359 	return platform_driver_register(&max8997_led_driver);
360 }
361 module_init(max8997_led_init);
362 
363 static void __exit max8997_led_exit(void)
364 {
365 	platform_driver_unregister(&max8997_led_driver);
366 }
367 module_exit(max8997_led_exit);
368 
369 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
370 MODULE_DESCRIPTION("MAX8997 LED driver");
371 MODULE_LICENSE("GPL");
372 MODULE_ALIAS("platform:max8997-led");
373