xref: /openbmc/linux/drivers/leds/leds-max8997.c (revision 57d91e03)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * leds-max8997.c - LED class driver for MAX8997 LEDs.
4  *
5  * Copyright (C) 2011 Samsung Electronics
6  * Donggeun Kim <dg77.kim@samsung.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/err.h>
11 #include <linux/slab.h>
12 #include <linux/leds.h>
13 #include <linux/mfd/max8997.h>
14 #include <linux/mfd/max8997-private.h>
15 #include <linux/platform_device.h>
16 
17 #define MAX8997_LED_FLASH_SHIFT			3
18 #define MAX8997_LED_FLASH_CUR_MASK		0xf8
19 #define MAX8997_LED_MOVIE_SHIFT			4
20 #define MAX8997_LED_MOVIE_CUR_MASK		0xf0
21 
22 #define MAX8997_LED_FLASH_MAX_BRIGHTNESS	0x1f
23 #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS	0xf
24 #define MAX8997_LED_NONE_MAX_BRIGHTNESS		0
25 
26 #define MAX8997_LED0_FLASH_MASK			0x1
27 #define MAX8997_LED0_FLASH_PIN_MASK		0x5
28 #define MAX8997_LED0_MOVIE_MASK			0x8
29 #define MAX8997_LED0_MOVIE_PIN_MASK		0x28
30 
31 #define MAX8997_LED1_FLASH_MASK			0x2
32 #define MAX8997_LED1_FLASH_PIN_MASK		0x6
33 #define MAX8997_LED1_MOVIE_MASK			0x10
34 #define MAX8997_LED1_MOVIE_PIN_MASK		0x30
35 
36 #define MAX8997_LED_BOOST_ENABLE_MASK		(1 << 6)
37 
38 struct max8997_led {
39 	struct max8997_dev *iodev;
40 	struct led_classdev cdev;
41 	bool enabled;
42 	int id;
43 	enum max8997_led_mode led_mode;
44 	struct mutex mutex;
45 };
46 
max8997_led_set_mode(struct max8997_led * led,enum max8997_led_mode mode)47 static void max8997_led_set_mode(struct max8997_led *led,
48 			enum max8997_led_mode mode)
49 {
50 	int ret;
51 	struct i2c_client *client = led->iodev->i2c;
52 	u8 mask = 0, val;
53 
54 	switch (mode) {
55 	case MAX8997_FLASH_MODE:
56 		mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
57 		val = led->id ?
58 		      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
59 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
60 		break;
61 	case MAX8997_MOVIE_MODE:
62 		mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
63 		val = led->id ?
64 		      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
65 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
66 		break;
67 	case MAX8997_FLASH_PIN_CONTROL_MODE:
68 		mask = MAX8997_LED1_FLASH_PIN_MASK |
69 		       MAX8997_LED0_FLASH_PIN_MASK;
70 		val = led->id ?
71 		      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
72 		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
73 		break;
74 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
75 		mask = MAX8997_LED1_MOVIE_PIN_MASK |
76 		       MAX8997_LED0_MOVIE_PIN_MASK;
77 		val = led->id ?
78 		      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
79 		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
80 		break;
81 	default:
82 		led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
83 		break;
84 	}
85 
86 	if (mask) {
87 		ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
88 					 mask);
89 		if (ret)
90 			dev_err(led->iodev->dev,
91 				"failed to update register(%d)\n", ret);
92 	}
93 
94 	led->led_mode = mode;
95 }
96 
max8997_led_enable(struct max8997_led * led,bool enable)97 static void max8997_led_enable(struct max8997_led *led, bool enable)
98 {
99 	int ret;
100 	struct i2c_client *client = led->iodev->i2c;
101 	u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
102 
103 	if (led->enabled == enable)
104 		return;
105 
106 	val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
107 
108 	ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
109 	if (ret)
110 		dev_err(led->iodev->dev,
111 			"failed to update register(%d)\n", ret);
112 
113 	led->enabled = enable;
114 }
115 
max8997_led_set_current(struct max8997_led * led,enum led_brightness value)116 static void max8997_led_set_current(struct max8997_led *led,
117 				enum led_brightness value)
118 {
119 	int ret;
120 	struct i2c_client *client = led->iodev->i2c;
121 	u8 val = 0, mask = 0, reg = 0;
122 
123 	switch (led->led_mode) {
124 	case MAX8997_FLASH_MODE:
125 	case MAX8997_FLASH_PIN_CONTROL_MODE:
126 		val = value << MAX8997_LED_FLASH_SHIFT;
127 		mask = MAX8997_LED_FLASH_CUR_MASK;
128 		reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
129 		break;
130 	case MAX8997_MOVIE_MODE:
131 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
132 		val = value << MAX8997_LED_MOVIE_SHIFT;
133 		mask = MAX8997_LED_MOVIE_CUR_MASK;
134 		reg = MAX8997_REG_MOVIE_CUR;
135 		break;
136 	default:
137 		break;
138 	}
139 
140 	if (mask) {
141 		ret = max8997_update_reg(client, reg, val, mask);
142 		if (ret)
143 			dev_err(led->iodev->dev,
144 				"failed to update register(%d)\n", ret);
145 	}
146 }
147 
max8997_led_brightness_set(struct led_classdev * led_cdev,enum led_brightness value)148 static void max8997_led_brightness_set(struct led_classdev *led_cdev,
149 				enum led_brightness value)
150 {
151 	struct max8997_led *led =
152 			container_of(led_cdev, struct max8997_led, cdev);
153 
154 	if (value) {
155 		max8997_led_set_current(led, value);
156 		max8997_led_enable(led, true);
157 	} else {
158 		max8997_led_set_current(led, value);
159 		max8997_led_enable(led, false);
160 	}
161 }
162 
mode_show(struct device * dev,struct device_attribute * attr,char * buf)163 static ssize_t mode_show(struct device *dev,
164 			 struct device_attribute *attr, char *buf)
165 {
166 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
167 	struct max8997_led *led =
168 			container_of(led_cdev, struct max8997_led, cdev);
169 	ssize_t ret = 0;
170 
171 	mutex_lock(&led->mutex);
172 
173 	switch (led->led_mode) {
174 	case MAX8997_FLASH_MODE:
175 		ret += sprintf(buf, "FLASH\n");
176 		break;
177 	case MAX8997_MOVIE_MODE:
178 		ret += sprintf(buf, "MOVIE\n");
179 		break;
180 	case MAX8997_FLASH_PIN_CONTROL_MODE:
181 		ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
182 		break;
183 	case MAX8997_MOVIE_PIN_CONTROL_MODE:
184 		ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
185 		break;
186 	default:
187 		ret += sprintf(buf, "NONE\n");
188 		break;
189 	}
190 
191 	mutex_unlock(&led->mutex);
192 
193 	return ret;
194 }
195 
mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)196 static ssize_t mode_store(struct device *dev,
197 			  struct device_attribute *attr,
198 			  const char *buf, size_t size)
199 {
200 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
201 	struct max8997_led *led =
202 			container_of(led_cdev, struct max8997_led, cdev);
203 	enum max8997_led_mode mode;
204 
205 	mutex_lock(&led->mutex);
206 
207 	if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
208 		mode = MAX8997_FLASH_PIN_CONTROL_MODE;
209 	else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
210 		mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
211 	else if (!strncmp(buf, "FLASH", 5))
212 		mode = MAX8997_FLASH_MODE;
213 	else if (!strncmp(buf, "MOVIE", 5))
214 		mode = MAX8997_MOVIE_MODE;
215 	else
216 		mode = MAX8997_NONE;
217 
218 	max8997_led_set_mode(led, mode);
219 
220 	mutex_unlock(&led->mutex);
221 
222 	return size;
223 }
224 
225 static DEVICE_ATTR_RW(mode);
226 
227 static struct attribute *max8997_attrs[] = {
228 	&dev_attr_mode.attr,
229 	NULL
230 };
231 ATTRIBUTE_GROUPS(max8997);
232 
max8997_led_probe(struct platform_device * pdev)233 static int max8997_led_probe(struct platform_device *pdev)
234 {
235 	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
236 	struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
237 	struct max8997_led *led;
238 	char name[20];
239 	int ret = 0;
240 
241 	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
242 	if (led == NULL)
243 		return -ENOMEM;
244 
245 	led->id = pdev->id;
246 	snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
247 
248 	led->cdev.name = name;
249 	led->cdev.brightness_set = max8997_led_brightness_set;
250 	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
251 	led->cdev.brightness = 0;
252 	led->cdev.groups = max8997_groups;
253 	led->iodev = iodev;
254 
255 	/* initialize mode and brightness according to platform_data */
256 	if (pdata && pdata->led_pdata) {
257 		u8 mode = 0, brightness = 0;
258 
259 		mode = pdata->led_pdata->mode[led->id];
260 		brightness = pdata->led_pdata->brightness[led->id];
261 
262 		max8997_led_set_mode(led, mode);
263 
264 		if (brightness > led->cdev.max_brightness)
265 			brightness = led->cdev.max_brightness;
266 		max8997_led_set_current(led, brightness);
267 		led->cdev.brightness = brightness;
268 	} else {
269 		max8997_led_set_mode(led, MAX8997_NONE);
270 		max8997_led_set_current(led, 0);
271 	}
272 
273 	mutex_init(&led->mutex);
274 
275 	ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
276 	if (ret < 0)
277 		return ret;
278 
279 	return 0;
280 }
281 
282 static struct platform_driver max8997_led_driver = {
283 	.driver = {
284 		.name  = "max8997-led",
285 	},
286 	.probe  = max8997_led_probe,
287 };
288 
289 module_platform_driver(max8997_led_driver);
290 
291 MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
292 MODULE_DESCRIPTION("MAX8997 LED driver");
293 MODULE_LICENSE("GPL");
294 MODULE_ALIAS("platform:max8997-led");
295