xref: /linux/drivers/leds/leds-max8997.c (revision 3821a065f5672c430a088ae68b4da2a2d2b34106)
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_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 struct attribute *max8997_attrs[] = {
233 	&dev_attr_mode.attr,
234 	NULL
235 };
236 ATTRIBUTE_GROUPS(max8997);
237 
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 
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