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
43struct 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
52static 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
102static 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
121static 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
153static 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
168static 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
201static 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
230static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
231
232static struct attribute *max8997_attrs[] = {
233	&dev_attr_mode.attr,
234	NULL
235};
236ATTRIBUTE_GROUPS(max8997);
237
238static 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
294static 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
303static 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
311module_platform_driver(max8997_led_driver);
312
313MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
314MODULE_DESCRIPTION("MAX8997 LED driver");
315MODULE_LICENSE("GPL");
316MODULE_ALIAS("platform:max8997-led");
317