linux/drivers/video/backlight/locomolcd.c
Henrique de Moraes Holschuh 4437cd1e98 [PATCH] backlight: do not power off backlight when unregistering
ACPI drivers like ibm-acpi are moving to the backlight sysfs
infrastructure.  During ibm-acpi testing, I have noticed that
backlight_device_unregister() sets the display brightness and power to
zero.

This causes the display to be dimmed on ibm-acpi module removal.  It will
affect all other ACPI drivers that are being converted to use the backlight
class, as well.  It also affects a number of framebuffer devices that are
used on desktops and laptops which might also not want such behaviour.

Since working around this behaviour requires undesireable hacks, Richard
Purdie decided that we would be better off reverting the changes in the
sysfs class, and adding the code to dim and power off the backlight device
to the drivers that want it.  This patch is my attempt to do so.

Patch against latest linux-2.6.git.  Changes untested, as I lack the
required hardware.  Still, they are trivial enough that, apart from typos,
there is little chance of getting them wrong.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:29:07 -08:00

249 lines
6.2 KiB
C

/*
* Backlight control code for Sharp Zaurus SL-5500
*
* Copyright 2005 John Lenz <lenz@cs.wisc.edu>
* Maintainer: Pavel Machek <pavel@suse.cz> (unless John wants to :-)
* GPL v2
*
* This driver assumes single CPU. That's okay, because collie is
* slightly old hardware, and noone is going to retrofit second CPU to
* old PDA.
*/
/* LCD power functions */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <asm/hardware/locomo.h>
#include <asm/irq.h>
#include <asm/mach/sharpsl_param.h>
#include <asm/mach-types.h>
#include "../../../arch/arm/mach-sa1100/generic.h"
static struct backlight_device *locomolcd_bl_device;
static struct locomo_dev *locomolcd_dev;
static unsigned long locomolcd_flags;
#define LOCOMOLCD_SUSPENDED 0x01
static void locomolcd_on(int comadj)
{
locomo_gpio_set_dir(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHA_ON, 0);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHA_ON, 1);
mdelay(2);
locomo_gpio_set_dir(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHD_ON, 0);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHD_ON, 1);
mdelay(2);
locomo_m62332_senddata(locomolcd_dev, comadj, 0);
mdelay(5);
locomo_gpio_set_dir(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VEE_ON, 0);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VEE_ON, 1);
mdelay(10);
/* TFTCRST | CPSOUT=0 | CPSEN */
locomo_writel(0x01, locomolcd_dev->mapbase + LOCOMO_TC);
/* Set CPSD */
locomo_writel(6, locomolcd_dev->mapbase + LOCOMO_CPSD);
/* TFTCRST | CPSOUT=0 | CPSEN */
locomo_writel((0x04 | 0x01), locomolcd_dev->mapbase + LOCOMO_TC);
mdelay(10);
locomo_gpio_set_dir(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_MOD, 0);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_MOD, 1);
}
static void locomolcd_off(int comadj)
{
/* TFTCRST=1 | CPSOUT=1 | CPSEN = 0 */
locomo_writel(0x06, locomolcd_dev->mapbase + LOCOMO_TC);
mdelay(1);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHA_ON, 0);
mdelay(110);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VEE_ON, 0);
mdelay(700);
/* TFTCRST=0 | CPSOUT=0 | CPSEN = 0 */
locomo_writel(0, locomolcd_dev->mapbase + LOCOMO_TC);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_MOD, 0);
locomo_gpio_write(locomolcd_dev->dev.parent, LOCOMO_GPIO_LCD_VSHD_ON, 0);
}
void locomolcd_power(int on)
{
int comadj = sharpsl_param.comadj;
unsigned long flags;
local_irq_save(flags);
if (!locomolcd_dev) {
local_irq_restore(flags);
return;
}
/* read comadj */
if (comadj == -1 && machine_is_collie())
comadj = 128;
if (comadj == -1 && machine_is_poodle())
comadj = 118;
if (on)
locomolcd_on(comadj);
else
locomolcd_off(comadj);
local_irq_restore(flags);
}
EXPORT_SYMBOL(locomolcd_power);
static int current_intensity;
static int locomolcd_set_intensity(struct backlight_device *bd)
{
int intensity = bd->props->brightness;
if (bd->props->power != FB_BLANK_UNBLANK)
intensity = 0;
if (bd->props->fb_blank != FB_BLANK_UNBLANK)
intensity = 0;
if (locomolcd_flags & LOCOMOLCD_SUSPENDED)
intensity = 0;
switch (intensity) {
/* AC and non-AC are handled differently, but produce same results in sharp code? */
case 0: locomo_frontlight_set(locomolcd_dev, 0, 0, 161); break;
case 1: locomo_frontlight_set(locomolcd_dev, 117, 0, 161); break;
case 2: locomo_frontlight_set(locomolcd_dev, 163, 0, 148); break;
case 3: locomo_frontlight_set(locomolcd_dev, 194, 0, 161); break;
case 4: locomo_frontlight_set(locomolcd_dev, 194, 1, 161); break;
default:
return -ENODEV;
}
current_intensity = intensity;
return 0;
}
static int locomolcd_get_intensity(struct backlight_device *bd)
{
return current_intensity;
}
static struct backlight_properties locomobl_data = {
.owner = THIS_MODULE,
.get_brightness = locomolcd_get_intensity,
.update_status = locomolcd_set_intensity,
.max_brightness = 4,
};
#ifdef CONFIG_PM
static int locomolcd_suspend(struct locomo_dev *dev, pm_message_t state)
{
locomolcd_flags |= LOCOMOLCD_SUSPENDED;
locomolcd_set_intensity(locomolcd_bl_device);
return 0;
}
static int locomolcd_resume(struct locomo_dev *dev)
{
locomolcd_flags &= ~LOCOMOLCD_SUSPENDED;
locomolcd_set_intensity(locomolcd_bl_device);
return 0;
}
#else
#define locomolcd_suspend NULL
#define locomolcd_resume NULL
#endif
static int locomolcd_probe(struct locomo_dev *ldev)
{
unsigned long flags;
local_irq_save(flags);
locomolcd_dev = ldev;
locomo_gpio_set_dir(ldev->dev.parent, LOCOMO_GPIO_FL_VR, 0);
/* the poodle_lcd_power function is called for the first time
* from fs_initcall, which is before locomo is activated.
* We need to recall poodle_lcd_power here*/
if (machine_is_poodle())
locomolcd_power(1);
local_irq_restore(flags);
locomolcd_bl_device = backlight_device_register("locomo-bl", NULL, &locomobl_data);
if (IS_ERR (locomolcd_bl_device))
return PTR_ERR (locomolcd_bl_device);
/* Set up frontlight so that screen is readable */
locomobl_data.brightness = 2;
locomolcd_set_intensity(locomolcd_bl_device);
return 0;
}
static int locomolcd_remove(struct locomo_dev *dev)
{
unsigned long flags;
locomobl_data.brightness = 0;
locomobl_data.power = 0;
locomolcd_set_intensity(locomolcd_bl_device);
backlight_device_unregister(locomolcd_bl_device);
local_irq_save(flags);
locomolcd_dev = NULL;
local_irq_restore(flags);
return 0;
}
static struct locomo_driver poodle_lcd_driver = {
.drv = {
.name = "locomo-backlight",
},
.devid = LOCOMO_DEVID_BACKLIGHT,
.probe = locomolcd_probe,
.remove = locomolcd_remove,
.suspend = locomolcd_suspend,
.resume = locomolcd_resume,
};
static int __init locomolcd_init(void)
{
int ret = locomo_driver_register(&poodle_lcd_driver);
if (ret)
return ret;
#ifdef CONFIG_SA1100_COLLIE
sa1100fb_lcd_power = locomolcd_power;
#endif
return 0;
}
static void __exit locomolcd_exit(void)
{
locomo_driver_unregister(&poodle_lcd_driver);
}
module_init(locomolcd_init);
module_exit(locomolcd_exit);
MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>, Pavel Machek <pavel@suse.cz>");
MODULE_DESCRIPTION("Collie LCD driver");
MODULE_LICENSE("GPL");