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