xref: /openbmc/linux/drivers/leds/leds-max8997.c (revision e6e8c82b)
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/leds.h>
17 #include <linux/mfd/max8997.h>
18 #include <linux/mfd/max8997-private.h>
19 #include <linux/platform_device.h>
20 
21 #define MAX8997_LED_FLASH_SHIFT			3
22 #define MAX8997_LED_FLASH_CUR_MASK		0xf8
23 #define MAX8997_LED_MOVIE_SHIFT			4
24 #define MAX8997_LED_MOVIE_CUR_MASK		0xf0
25 
26 #define MAX8997_LED_FLASH_MAX_BRIGHTNESS	0x1f
27 #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS	0xf
28 #define MAX8997_LED_NONE_MAX_BRIGHTNESS		0
29 
30 #define MAX8997_LED0_FLASH_MASK			0x1
31 #define MAX8997_LED0_FLASH_PIN_MASK		0x5
32 #define MAX8997_LED0_MOVIE_MASK			0x8
33 #define MAX8997_LED0_MOVIE_PIN_MASK		0x28
34 
35 #define MAX8997_LED1_FLASH_MASK			0x2
36 #define MAX8997_LED1_FLASH_PIN_MASK		0x6
37 #define MAX8997_LED1_MOVIE_MASK			0x10
38 #define MAX8997_LED1_MOVIE_PIN_MASK		0x30
39 
40 #define MAX8997_LED_BOOST_ENABLE_MASK		(1 << 6)
41 
42 struct max8997_led {
43 	struct max8997_dev *iodev;
44 	struct led_classdev cdev;
45 	bool enabled;
46 	int id;
47 	enum max8997_led_mode led_mode;
48 	struct mutex mutex;
49 };
50 
51 static void max8997_led_set_mode(struct max8997_led *led,
52 			enum max8997_led_mode mode)
53 {
54 	int ret;
55 	struct i2c_client *client = led->iodev->i2c;
56 	u8 mask = 0, val;
57 
58 	switch (mode) {
59 	case MAX8997_FLASH_MODE:
60 		mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
61 		val = led->id ?
62 		      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
63 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
64 		break;
65 	case MAX8997_MOVIE_MODE:
66 		mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
67 		val = led->id ?
68 		      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
69 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
70 		break;
71 	case MAX8997_FLASH_PIN_CONTROL_MODE:
72 		mask = MAX8997_LED1_FLASH_PIN_MASK |
73 		       MAX8997_LED0_FLASH_PIN_MASK;
74 		val = led->id ?
75 		      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
76 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
77 		break;
78 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
79 		mask = MAX8997_LED1_MOVIE_PIN_MASK |
80 		       MAX8997_LED0_MOVIE_PIN_MASK;
81 		val = led->id ?
82 		      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
83 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
84 		break;
85 	default:
86 		led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
87 		break;
88 	}
89 
90 	if (mask) {
91 		ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
92 					 mask);
93 		if (ret)
94 			dev_err(led->iodev->dev,
95 				"failed to update register(%d)\n", ret);
96 	}
97 
98 	led->led_mode = mode;
99 }
100 
101 static void max8997_led_enable(struct max8997_led *led, bool enable)
102 {
103 	int ret;
104 	struct i2c_client *client = led->iodev->i2c;
105 	u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
106 
107 	if (led->enabled == enable)
108 		return;
109 
110 	val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
111 
112 	ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
113 	if (ret)
114 		dev_err(led->iodev->dev,
115 			"failed to update register(%d)\n", ret);
116 
117 	led->enabled = enable;
118 }
119 
120 static void max8997_led_set_current(struct max8997_led *led,
121 				enum led_brightness value)
122 {
123 	int ret;
124 	struct i2c_client *client = led->iodev->i2c;
125 	u8 val = 0, mask = 0, reg = 0;
126 
127 	switch (led->led_mode) {
128 	case MAX8997_FLASH_MODE:
129 	case MAX8997_FLASH_PIN_CONTROL_MODE:
130 		val = value << MAX8997_LED_FLASH_SHIFT;
131 		mask = MAX8997_LED_FLASH_CUR_MASK;
132 		reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
133 		break;
134 	case MAX8997_MOVIE_MODE:
135 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
136 		val = value << MAX8997_LED_MOVIE_SHIFT;
137 		mask = MAX8997_LED_MOVIE_CUR_MASK;
138 		reg = MAX8997_REG_MOVIE_CUR;
139 		break;
140 	default:
141 		break;
142 	}
143 
144 	if (mask) {
145 		ret = max8997_update_reg(client, reg, val, mask);
146 		if (ret)
147 			dev_err(led->iodev->dev,
148 				"failed to update register(%d)\n", ret);
149 	}
150 }
151 
152 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
153 				enum led_brightness value)
154 {
155 	struct max8997_led *led =
156 			container_of(led_cdev, struct max8997_led, cdev);
157 
158 	if (value) {
159 		max8997_led_set_current(led, value);
160 		max8997_led_enable(led, true);
161 	} else {
162 		max8997_led_set_current(led, value);
163 		max8997_led_enable(led, false);
164 	}
165 }
166 
167 static ssize_t max8997_led_show_mode(struct device *dev,
168 				struct device_attribute *attr, char *buf)
169 {
170 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
171 	struct max8997_led *led =
172 			container_of(led_cdev, struct max8997_led, cdev);
173 	ssize_t ret = 0;
174 
175 	mutex_lock(&led->mutex);
176 
177 	switch (led->led_mode) {
178 	case MAX8997_FLASH_MODE:
179 		ret += sprintf(buf, "FLASH\n");
180 		break;
181 	case MAX8997_MOVIE_MODE:
182 		ret += sprintf(buf, "MOVIE\n");
183 		break;
184 	case MAX8997_FLASH_PIN_CONTROL_MODE:
185 		ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
186 		break;
187 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
188 		ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
189 		break;
190 	default:
191 		ret += sprintf(buf, "NONE\n");
192 		break;
193 	}
194 
195 	mutex_unlock(&led->mutex);
196 
197 	return ret;
198 }
199 
200 static ssize_t max8997_led_store_mode(struct device *dev,
201 				struct device_attribute *attr,
202 				const char *buf, size_t size)
203 {
204 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
205 	struct max8997_led *led =
206 			container_of(led_cdev, struct max8997_led, cdev);
207 	enum max8997_led_mode mode;
208 
209 	mutex_lock(&led->mutex);
210 
211 	if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
212 		mode = MAX8997_FLASH_PIN_CONTROL_MODE;
213 	else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
214 		mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
215 	else if (!strncmp(buf, "FLASH", 5))
216 		mode = MAX8997_FLASH_MODE;
217 	else if (!strncmp(buf, "MOVIE", 5))
218 		mode = MAX8997_MOVIE_MODE;
219 	else
220 		mode = MAX8997_NONE;
221 
222 	max8997_led_set_mode(led, mode);
223 
224 	mutex_unlock(&led->mutex);
225 
226 	return size;
227 }
228 
229 static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
230 
231 static struct attribute *max8997_attrs[] = {
232 	&dev_attr_mode.attr,
233 	NULL
234 };
235 ATTRIBUTE_GROUPS(max8997);
236 
237 static int max8997_led_probe(struct platform_device *pdev)
238 {
239 	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
240 	struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
241 	struct max8997_led *led;
242 	char name[20];
243 	int ret = 0;
244 
245 	if (pdata == NULL) {
246 		dev_err(&pdev->dev, "no platform data\n");
247 		return -ENODEV;
248 	}
249 
250 	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
251 	if (led == NULL)
252 		return -ENOMEM;
253 
254 	led->id = pdev->id;
255 	snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
256 
257 	led->cdev.name = name;
258 	led->cdev.brightness_set = max8997_led_brightness_set;
259 	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
260 	led->cdev.brightness = 0;
261 	led->cdev.groups = max8997_groups;
262 	led->iodev = iodev;
263 
264 	/* initialize mode and brightness according to platform_data */
265 	if (pdata->led_pdata) {
266 		u8 mode = 0, brightness = 0;
267 
268 		mode = pdata->led_pdata->mode[led->id];
269 		brightness = pdata->led_pdata->brightness[led->id];
270 
271 		max8997_led_set_mode(led, mode);
272 
273 		if (brightness > led->cdev.max_brightness)
274 			brightness = led->cdev.max_brightness;
275 		max8997_led_set_current(led, brightness);
276 		led->cdev.brightness = brightness;
277 	} else {
278 		max8997_led_set_mode(led, MAX8997_NONE);
279 		max8997_led_set_current(led, 0);
280 	}
281 
282 	mutex_init(&led->mutex);
283 
284 	ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
285 	if (ret < 0)
286 		return ret;
287 
288 	return 0;
289 }
290 
291 static struct platform_driver max8997_led_driver = {
292 	.driver = {
293 		.name  = "max8997-led",
294 	},
295 	.probe  = max8997_led_probe,
296 };
297 
298 module_platform_driver(max8997_led_driver);
299 
300 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
301 MODULE_DESCRIPTION("MAX8997 LED driver");
302 MODULE_LICENSE("GPL");
303 MODULE_ALIAS("platform:max8997-led");
304