[go: nahoru, domu]
1/*
2 * LED Driver for Dialog DA9052 PMICs.
3 *
4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
5 *
6 * Author: David Dajun Chen <dchen@diasemi.com>
7 *
8 *  This program is free software; you can redistribute  it and/or modify it
9 *  under  the terms of  the GNU General  Public License as published by the
10 *  Free Software Foundation;  either version 2 of the  License, or (at your
11 *  option) any later version.
12 *
13 */
14
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/platform_device.h>
18#include <linux/leds.h>
19#include <linux/workqueue.h>
20#include <linux/slab.h>
21
22#include <linux/mfd/da9052/reg.h>
23#include <linux/mfd/da9052/da9052.h>
24#include <linux/mfd/da9052/pdata.h>
25
26#define DA9052_OPENDRAIN_OUTPUT	2
27#define DA9052_SET_HIGH_LVL_OUTPUT	(1 << 3)
28#define DA9052_MASK_UPPER_NIBBLE	0xF0
29#define DA9052_MASK_LOWER_NIBBLE	0x0F
30#define DA9052_NIBBLE_SHIFT		4
31#define DA9052_MAX_BRIGHTNESS		0x5f
32
33struct da9052_led {
34	struct led_classdev cdev;
35	struct work_struct work;
36	struct da9052 *da9052;
37	unsigned char led_index;
38	unsigned char id;
39	int brightness;
40};
41
42static unsigned char led_reg[] = {
43	DA9052_LED_CONT_4_REG,
44	DA9052_LED_CONT_5_REG,
45};
46
47static int da9052_set_led_brightness(struct da9052_led *led)
48{
49	u8 val;
50	int error;
51
52	val = (led->brightness & 0x7f) | DA9052_LED_CONT_DIM;
53
54	error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
55	if (error < 0)
56		dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
57			error);
58	return error;
59}
60
61static void da9052_led_work(struct work_struct *work)
62{
63	struct da9052_led *led = container_of(work, struct da9052_led, work);
64
65	da9052_set_led_brightness(led);
66}
67
68static void da9052_led_set(struct led_classdev *led_cdev,
69			   enum led_brightness value)
70{
71	struct da9052_led *led;
72
73	led = container_of(led_cdev, struct da9052_led, cdev);
74	led->brightness = value;
75	schedule_work(&led->work);
76}
77
78static int da9052_configure_leds(struct da9052 *da9052)
79{
80	int error;
81	unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
82				       | DA9052_SET_HIGH_LVL_OUTPUT;
83
84	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
85				  DA9052_MASK_LOWER_NIBBLE,
86				  register_value);
87
88	if (error < 0) {
89		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
90			error);
91		return error;
92	}
93
94	error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
95				  DA9052_MASK_UPPER_NIBBLE,
96				  register_value << DA9052_NIBBLE_SHIFT);
97	if (error < 0)
98		dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
99			error);
100
101	return error;
102}
103
104static int da9052_led_probe(struct platform_device *pdev)
105{
106	struct da9052_pdata *pdata;
107	struct da9052 *da9052;
108	struct led_platform_data *pled;
109	struct da9052_led *led = NULL;
110	int error = -ENODEV;
111	int i;
112
113	da9052 = dev_get_drvdata(pdev->dev.parent);
114	pdata = dev_get_platdata(da9052->dev);
115	if (pdata == NULL) {
116		dev_err(&pdev->dev, "No platform data\n");
117		goto err;
118	}
119
120	pled = pdata->pled;
121	if (pled == NULL) {
122		dev_err(&pdev->dev, "No platform data for LED\n");
123		goto err;
124	}
125
126	led = devm_kzalloc(&pdev->dev,
127			   sizeof(struct da9052_led) * pled->num_leds,
128			   GFP_KERNEL);
129	if (!led) {
130		error = -ENOMEM;
131		goto err;
132	}
133
134	for (i = 0; i < pled->num_leds; i++) {
135		led[i].cdev.name = pled->leds[i].name;
136		led[i].cdev.brightness_set = da9052_led_set;
137		led[i].cdev.brightness = LED_OFF;
138		led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
139		led[i].brightness = LED_OFF;
140		led[i].led_index = pled->leds[i].flags;
141		led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
142		INIT_WORK(&led[i].work, da9052_led_work);
143
144		error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
145		if (error) {
146			dev_err(&pdev->dev, "Failed to register led %d\n",
147				led[i].led_index);
148			goto err_register;
149		}
150
151		error = da9052_set_led_brightness(&led[i]);
152		if (error) {
153			dev_err(&pdev->dev, "Unable to init led %d\n",
154				led[i].led_index);
155			continue;
156		}
157	}
158	error = da9052_configure_leds(led->da9052);
159	if (error) {
160		dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
161		goto err_register;
162	}
163
164	platform_set_drvdata(pdev, led);
165
166	return 0;
167
168err_register:
169	for (i = i - 1; i >= 0; i--) {
170		led_classdev_unregister(&led[i].cdev);
171		cancel_work_sync(&led[i].work);
172	}
173err:
174	return error;
175}
176
177static int da9052_led_remove(struct platform_device *pdev)
178{
179	struct da9052_led *led = platform_get_drvdata(pdev);
180	struct da9052_pdata *pdata;
181	struct da9052 *da9052;
182	struct led_platform_data *pled;
183	int i;
184
185	da9052 = dev_get_drvdata(pdev->dev.parent);
186	pdata = dev_get_platdata(da9052->dev);
187	pled = pdata->pled;
188
189	for (i = 0; i < pled->num_leds; i++) {
190		led[i].brightness = 0;
191		da9052_set_led_brightness(&led[i]);
192		led_classdev_unregister(&led[i].cdev);
193		cancel_work_sync(&led[i].work);
194	}
195
196	return 0;
197}
198
199static struct platform_driver da9052_led_driver = {
200	.driver		= {
201		.name	= "da9052-leds",
202		.owner	= THIS_MODULE,
203	},
204	.probe		= da9052_led_probe,
205	.remove		= da9052_led_remove,
206};
207
208module_platform_driver(da9052_led_driver);
209
210MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
211MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
212MODULE_LICENSE("GPL");
213