backlight: add driver for DA9052/53 PMIC v1
[~shefty/rdma-dev.git] / drivers / video / backlight / da9052_bl.c
1 /*
2  * Backlight 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
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  */
14
15 #include <linux/backlight.h>
16 #include <linux/delay.h>
17 #include <linux/fb.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20
21 #include <linux/mfd/da9052/da9052.h>
22 #include <linux/mfd/da9052/reg.h>
23
24 #define DA9052_MAX_BRIGHTNESS           0xFF
25
26 enum {
27         DA9052_WLEDS_OFF,
28         DA9052_WLEDS_ON,
29 };
30
31 enum {
32         DA9052_TYPE_WLED1,
33         DA9052_TYPE_WLED2,
34         DA9052_TYPE_WLED3,
35 };
36
37 static unsigned char wled_bank[] = {
38         DA9052_LED1_CONF_REG,
39         DA9052_LED2_CONF_REG,
40         DA9052_LED3_CONF_REG,
41 };
42
43 struct da9052_bl {
44         struct da9052 *da9052;
45         uint brightness;
46         uint state;
47         uint led_reg;
48 };
49
50 static int da9052_adjust_wled_brightness(struct da9052_bl *wleds)
51 {
52         unsigned char boost_en;
53         unsigned char i_sink;
54         int ret;
55
56         boost_en = 0x3F;
57         i_sink = 0xFF;
58         if (wleds->state == DA9052_WLEDS_OFF) {
59                 boost_en = 0x00;
60                 i_sink = 0x00;
61         }
62
63         ret = da9052_reg_write(wleds->da9052, DA9052_BOOST_REG, boost_en);
64         if (ret < 0)
65                 return ret;
66
67         ret = da9052_reg_write(wleds->da9052, DA9052_LED_CONT_REG, i_sink);
68         if (ret < 0)
69                 return ret;
70
71         ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 0x0);
72         if (ret < 0)
73                 return ret;
74
75         msleep(10);
76
77         if (wleds->brightness) {
78                 ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg],
79                                        wleds->brightness);
80                 if (ret < 0)
81                         return ret;
82         }
83
84         return 0;
85 }
86
87 static int da9052_backlight_update_status(struct backlight_device *bl)
88 {
89         int brightness = bl->props.brightness;
90         struct da9052_bl *wleds = bl_get_data(bl);
91
92         wleds->brightness = brightness;
93         wleds->state = DA9052_WLEDS_ON;
94
95         return da9052_adjust_wled_brightness(wleds);
96 }
97
98 static int da9052_backlight_get_brightness(struct backlight_device *bl)
99 {
100         struct da9052_bl *wleds = bl_get_data(bl);
101
102         return wleds->brightness;
103 }
104
105 static const struct backlight_ops da9052_backlight_ops = {
106         .update_status = da9052_backlight_update_status,
107         .get_brightness = da9052_backlight_get_brightness,
108 };
109
110 static int da9052_backlight_probe(struct platform_device *pdev)
111 {
112         struct backlight_device *bl;
113         struct backlight_properties props;
114         struct da9052_bl *wleds;
115
116         wleds = devm_kzalloc(&pdev->dev, sizeof(struct da9052_bl), GFP_KERNEL);
117         if (!wleds)
118                 return -ENOMEM;
119
120         wleds->da9052 = dev_get_drvdata(pdev->dev.parent);
121         wleds->brightness = 0;
122         wleds->led_reg = platform_get_device_id(pdev)->driver_data;
123         wleds->state = DA9052_WLEDS_OFF;
124
125         props.type = BACKLIGHT_RAW;
126         props.max_brightness = DA9052_MAX_BRIGHTNESS;
127
128         bl = backlight_device_register(pdev->name, wleds->da9052->dev, wleds,
129                                        &da9052_backlight_ops, &props);
130         if (IS_ERR(bl)) {
131                 dev_err(&pdev->dev, "Failed to register backlight\n");
132                 devm_kfree(&pdev->dev, wleds);
133                 return PTR_ERR(bl);
134         }
135
136         bl->props.max_brightness = DA9052_MAX_BRIGHTNESS;
137         bl->props.brightness = 0;
138         platform_set_drvdata(pdev, bl);
139
140         return da9052_adjust_wled_brightness(wleds);
141 }
142
143 static int da9052_backlight_remove(struct platform_device *pdev)
144 {
145         struct backlight_device *bl = platform_get_drvdata(pdev);
146         struct da9052_bl *wleds = bl_get_data(bl);
147
148         wleds->brightness = 0;
149         wleds->state = DA9052_WLEDS_OFF;
150         da9052_adjust_wled_brightness(wleds);
151         backlight_device_unregister(bl);
152         devm_kfree(&pdev->dev, wleds);
153
154         return 0;
155 }
156
157 static struct platform_device_id da9052_wled_ids[] = {
158         {
159                 .name           = "da9052-wled1",
160                 .driver_data    = DA9052_TYPE_WLED1,
161         },
162         {
163                 .name           = "da9052-wled2",
164                 .driver_data    = DA9052_TYPE_WLED2,
165         },
166         {
167                 .name           = "da9052-wled3",
168                 .driver_data    = DA9052_TYPE_WLED3,
169         },
170 };
171
172 static struct platform_driver da9052_wled_driver = {
173         .probe          = da9052_backlight_probe,
174         .remove         = da9052_backlight_remove,
175         .id_table       = da9052_wled_ids,
176         .driver = {
177                 .name   = "da9052-wled",
178                 .owner  = THIS_MODULE,
179         },
180 };
181
182 module_platform_driver(da9052_wled_driver);
183
184 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
185 MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC");
186 MODULE_LICENSE("GPL");
187 MODULE_ALIAS("platform:da9052-backlight");