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
38struct 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
47static 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
97static 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
116static 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
148static 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
163static 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
196static 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
225static DEVICE_ATTR_RW(mode);
226
227static struct attribute *max8997_attrs[] = {
228	&dev_attr_mode.attr,
229	NULL
230};
231ATTRIBUTE_GROUPS(max8997);
232
233static 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
282static struct platform_driver max8997_led_driver = {
283	.driver = {
284		.name  = "max8997-led",
285	},
286	.probe  = max8997_led_probe,
287};
288
289module_platform_driver(max8997_led_driver);
290
291MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
292MODULE_DESCRIPTION("MAX8997 LED driver");
293MODULE_LICENSE("GPL");
294MODULE_ALIAS("platform:max8997-led");
295