Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6] / drivers / video / backlight / omap1_bl.c
1 /*
2  * Backlight driver for OMAP based boards.
3  *
4  * Copyright (c) 2006 Andrzej Zaborowski  <balrog@zabor.org>
5  *
6  * This package is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This package is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this package; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  */
20
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/platform_device.h>
25 #include <linux/fb.h>
26 #include <linux/backlight.h>
27
28 #include <mach/hardware.h>
29 #include <mach/board.h>
30 #include <mach/mux.h>
31
32 #define OMAPBL_MAX_INTENSITY            0xff
33
34 struct omap_backlight {
35         int powermode;
36         int current_intensity;
37
38         struct device *dev;
39         struct omap_backlight_config *pdata;
40 };
41
42 static void inline omapbl_send_intensity(int intensity)
43 {
44         omap_writeb(intensity, OMAP_PWL_ENABLE);
45 }
46
47 static void inline omapbl_send_enable(int enable)
48 {
49         omap_writeb(enable, OMAP_PWL_CLK_ENABLE);
50 }
51
52 static void omapbl_blank(struct omap_backlight *bl, int mode)
53 {
54         if (bl->pdata->set_power)
55                 bl->pdata->set_power(bl->dev, mode);
56
57         switch (mode) {
58         case FB_BLANK_NORMAL:
59         case FB_BLANK_VSYNC_SUSPEND:
60         case FB_BLANK_HSYNC_SUSPEND:
61         case FB_BLANK_POWERDOWN:
62                 omapbl_send_intensity(0);
63                 omapbl_send_enable(0);
64                 break;
65
66         case FB_BLANK_UNBLANK:
67                 omapbl_send_intensity(bl->current_intensity);
68                 omapbl_send_enable(1);
69                 break;
70         }
71 }
72
73 #ifdef CONFIG_PM
74 static int omapbl_suspend(struct platform_device *pdev, pm_message_t state)
75 {
76         struct backlight_device *dev = platform_get_drvdata(pdev);
77         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
78
79         omapbl_blank(bl, FB_BLANK_POWERDOWN);
80         return 0;
81 }
82
83 static int omapbl_resume(struct platform_device *pdev)
84 {
85         struct backlight_device *dev = platform_get_drvdata(pdev);
86         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
87
88         omapbl_blank(bl, bl->powermode);
89         return 0;
90 }
91 #else
92 #define omapbl_suspend  NULL
93 #define omapbl_resume   NULL
94 #endif
95
96 static int omapbl_set_power(struct backlight_device *dev, int state)
97 {
98         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
99
100         omapbl_blank(bl, state);
101         bl->powermode = state;
102
103         return 0;
104 }
105
106 static int omapbl_update_status(struct backlight_device *dev)
107 {
108         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
109
110         if (bl->current_intensity != dev->props.brightness) {
111                 if (bl->powermode == FB_BLANK_UNBLANK)
112                         omapbl_send_intensity(dev->props.brightness);
113                 bl->current_intensity = dev->props.brightness;
114         }
115
116         if (dev->props.fb_blank != bl->powermode)
117                 omapbl_set_power(dev, dev->props.fb_blank);
118
119         return 0;
120 }
121
122 static int omapbl_get_intensity(struct backlight_device *dev)
123 {
124         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
125         return bl->current_intensity;
126 }
127
128 static struct backlight_ops omapbl_ops = {
129         .get_brightness = omapbl_get_intensity,
130         .update_status  = omapbl_update_status,
131 };
132
133 static int omapbl_probe(struct platform_device *pdev)
134 {
135         struct backlight_device *dev;
136         struct omap_backlight *bl;
137         struct omap_backlight_config *pdata = pdev->dev.platform_data;
138
139         if (!pdata)
140                 return -ENXIO;
141
142         omapbl_ops.check_fb = pdata->check_fb;
143
144         bl = kzalloc(sizeof(struct omap_backlight), GFP_KERNEL);
145         if (unlikely(!bl))
146                 return -ENOMEM;
147
148         dev = backlight_device_register("omap-bl", &pdev->dev, bl, &omapbl_ops);
149         if (IS_ERR(dev)) {
150                 kfree(bl);
151                 return PTR_ERR(dev);
152         }
153
154         bl->powermode = FB_BLANK_POWERDOWN;
155         bl->current_intensity = 0;
156
157         bl->pdata = pdata;
158         bl->dev = &pdev->dev;
159
160         platform_set_drvdata(pdev, dev);
161
162         omap_cfg_reg(PWL);      /* Conflicts with UART3 */
163
164         dev->props.fb_blank = FB_BLANK_UNBLANK;
165         dev->props.max_brightness = OMAPBL_MAX_INTENSITY;
166         dev->props.brightness = pdata->default_intensity;
167         omapbl_update_status(dev);
168
169         printk(KERN_INFO "OMAP LCD backlight initialised\n");
170
171         return 0;
172 }
173
174 static int omapbl_remove(struct platform_device *pdev)
175 {
176         struct backlight_device *dev = platform_get_drvdata(pdev);
177         struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
178
179         backlight_device_unregister(dev);
180         kfree(bl);
181
182         return 0;
183 }
184
185 static struct platform_driver omapbl_driver = {
186         .probe          = omapbl_probe,
187         .remove         = omapbl_remove,
188         .suspend        = omapbl_suspend,
189         .resume         = omapbl_resume,
190         .driver         = {
191                 .name   = "omap-bl",
192         },
193 };
194
195 static int __init omapbl_init(void)
196 {
197         return platform_driver_register(&omapbl_driver);
198 }
199
200 static void __exit omapbl_exit(void)
201 {
202         platform_driver_unregister(&omapbl_driver);
203 }
204
205 module_init(omapbl_init);
206 module_exit(omapbl_exit);
207
208 MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>");
209 MODULE_DESCRIPTION("OMAP LCD Backlight driver");
210 MODULE_LICENSE("GPL");