Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 | /*
*
* Backlight driver for HP Jornada 700 series (710/720/728)
* Copyright (C) 2006-2009 Kristoffer Ericson <kristoffer.ericson@gmail.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 or any later version as published by the Free Software Foundation.
*
*/
#include <linux/backlight.h>
#include <linux/device.h>
#include <linux/fb.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <mach/jornada720.h>
#include <mach/hardware.h>
#include <video/s1d13xxxfb.h>
#define BL_MAX_BRIGHT 255
#define BL_DEF_BRIGHT 25
static int jornada_bl_get_brightness(struct backlight_device *bd)
{
int ret;
/* check if backlight is on */
if (!(PPSR & PPC_LDD1))
return 0;
jornada_ssp_start();
/* cmd should return txdummy */
ret = jornada_ssp_byte(GETBRIGHTNESS);
if (jornada_ssp_byte(GETBRIGHTNESS) != TXDUMMY) {
dev_err(&bd->dev, "get brightness timeout\n");
jornada_ssp_end();
return -ETIMEDOUT;
} else {
/* exchange txdummy for value */
ret = jornada_ssp_byte(TXDUMMY);
}
jornada_ssp_end();
return BL_MAX_BRIGHT - ret;
}
static int jornada_bl_update_status(struct backlight_device *bd)
{
int ret = 0;
jornada_ssp_start();
/* If backlight is off then really turn it off */
if ((bd->props.power != FB_BLANK_UNBLANK) || (bd->props.fb_blank != FB_BLANK_UNBLANK)) {
ret = jornada_ssp_byte(BRIGHTNESSOFF);
if (ret != TXDUMMY) {
dev_info(&bd->dev, "brightness off timeout\n");
/* turn off backlight */
PPSR &= ~PPC_LDD1;
PPDR |= PPC_LDD1;
ret = -ETIMEDOUT;
}
} else /* turn on backlight */
PPSR |= PPC_LDD1;
/* send command to our mcu */
if (jornada_ssp_byte(SETBRIGHTNESS) != TXDUMMY) {
dev_info(&bd->dev, "failed to set brightness\n");
ret = -ETIMEDOUT;
goto out;
}
/*
* at this point we expect that the mcu has accepted
* our command and is waiting for our new value
* please note that maximum brightness is 255,
* but due to physical layout it is equal to 0, so we simply
* invert the value (MAX VALUE - NEW VALUE).
*/
if (jornada_ssp_byte(BL_MAX_BRIGHT - bd->props.brightness)
!= TXDUMMY) {
dev_err(&bd->dev, "set brightness failed\n");
ret = -ETIMEDOUT;
}
/*
* If infact we get an TXDUMMY as output we are happy and dont
* make any further comments about it
*/
out:
jornada_ssp_end();
return ret;
}
static const struct backlight_ops jornada_bl_ops = {
.get_brightness = jornada_bl_get_brightness,
.update_status = jornada_bl_update_status,
.options = BL_CORE_SUSPENDRESUME,
};
static int jornada_bl_probe(struct platform_device *pdev)
{
struct backlight_properties props;
int ret;
struct backlight_device *bd;
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = BL_MAX_BRIGHT;
bd = backlight_device_register(S1D_DEVICENAME, &pdev->dev, NULL,
&jornada_bl_ops, &props);
if (IS_ERR(bd)) {
ret = PTR_ERR(bd);
dev_err(&pdev->dev, "failed to register device, err=%x\n", ret);
return ret;
}
bd->props.power = FB_BLANK_UNBLANK;
bd->props.brightness = BL_DEF_BRIGHT;
/*
* note. make sure max brightness is set otherwise
* you will get seemingly non-related errors when
* trying to change brightness
*/
jornada_bl_update_status(bd);
platform_set_drvdata(pdev, bd);
dev_info(&pdev->dev, "HP Jornada 700 series backlight driver\n");
return 0;
}
static int jornada_bl_remove(struct platform_device *pdev)
{
struct backlight_device *bd = platform_get_drvdata(pdev);
backlight_device_unregister(bd);
return 0;
}
static struct platform_driver jornada_bl_driver = {
.probe = jornada_bl_probe,
.remove = jornada_bl_remove,
.driver = {
.name = "jornada_bl",
},
};
module_platform_driver(jornada_bl_driver);
MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson>");
MODULE_DESCRIPTION("HP Jornada 710/720/728 Backlight driver");
MODULE_LICENSE("GPL");
|