linux/arch/ppc/platforms/pmac_backlight.c

203 lines
4.6 KiB
C

/*
* Miscellaneous procedures for dealing with the PowerMac hardware.
* Contains support for the backlight.
*
* Copyright (C) 2000 Benjamin Herrenschmidt
*
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/reboot.h>
#include <linux/nvram.h>
#include <linux/console.h>
#include <asm/sections.h>
#include <asm/ptrace.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/nvram.h>
#include <asm/backlight.h>
#include <linux/adb.h>
#include <linux/pmu.h>
static struct backlight_controller *backlighter;
static void* backlighter_data;
static int backlight_autosave;
static int backlight_level = BACKLIGHT_MAX;
static int backlight_enabled = 1;
static int backlight_req_level = -1;
static int backlight_req_enable = -1;
static void backlight_callback(void *);
static DECLARE_WORK(backlight_work, backlight_callback, NULL);
void __pmac register_backlight_controller(struct backlight_controller *ctrler,
void *data, char *type)
{
struct device_node* bk_node;
char *prop;
int valid = 0;
/* There's already a matching controller, bail out */
if (backlighter != NULL)
return;
bk_node = find_devices("backlight");
#ifdef CONFIG_ADB_PMU
/* Special case for the old PowerBook since I can't test on it */
backlight_autosave = machine_is_compatible("AAPL,3400/2400")
|| machine_is_compatible("AAPL,3500");
if ((backlight_autosave
|| machine_is_compatible("AAPL,PowerBook1998")
|| machine_is_compatible("PowerBook1,1"))
&& !strcmp(type, "pmu"))
valid = 1;
#endif
if (bk_node) {
prop = get_property(bk_node, "backlight-control", NULL);
if (prop && !strncmp(prop, type, strlen(type)))
valid = 1;
}
if (!valid)
return;
backlighter = ctrler;
backlighter_data = data;
if (bk_node && !backlight_autosave)
prop = get_property(bk_node, "bklt", NULL);
else
prop = NULL;
if (prop) {
backlight_level = ((*prop)+1) >> 1;
if (backlight_level > BACKLIGHT_MAX)
backlight_level = BACKLIGHT_MAX;
}
#ifdef CONFIG_ADB_PMU
if (backlight_autosave) {
struct adb_request req;
pmu_request(&req, NULL, 2, 0xd9, 0);
while (!req.complete)
pmu_poll();
backlight_level = req.reply[0] >> 4;
}
#endif
acquire_console_sem();
if (!backlighter->set_enable(1, backlight_level, data))
backlight_enabled = 1;
release_console_sem();
printk(KERN_INFO "Registered \"%s\" backlight controller,"
"level: %d/15\n", type, backlight_level);
}
EXPORT_SYMBOL(register_backlight_controller);
void __pmac unregister_backlight_controller(struct backlight_controller
*ctrler, void *data)
{
/* We keep the current backlight level (for now) */
if (ctrler == backlighter && data == backlighter_data)
backlighter = NULL;
}
EXPORT_SYMBOL(unregister_backlight_controller);
static int __pmac __set_backlight_enable(int enable)
{
int rc;
if (!backlighter)
return -ENODEV;
acquire_console_sem();
rc = backlighter->set_enable(enable, backlight_level,
backlighter_data);
if (!rc)
backlight_enabled = enable;
release_console_sem();
return rc;
}
int __pmac set_backlight_enable(int enable)
{
if (!backlighter)
return -ENODEV;
backlight_req_enable = enable;
schedule_work(&backlight_work);
return 0;
}
EXPORT_SYMBOL(set_backlight_enable);
int __pmac get_backlight_enable(void)
{
if (!backlighter)
return -ENODEV;
return backlight_enabled;
}
EXPORT_SYMBOL(get_backlight_enable);
static int __pmac __set_backlight_level(int level)
{
int rc = 0;
if (!backlighter)
return -ENODEV;
if (level < BACKLIGHT_MIN)
level = BACKLIGHT_OFF;
if (level > BACKLIGHT_MAX)
level = BACKLIGHT_MAX;
acquire_console_sem();
if (backlight_enabled)
rc = backlighter->set_level(level, backlighter_data);
if (!rc)
backlight_level = level;
release_console_sem();
if (!rc && !backlight_autosave) {
level <<=1;
if (level & 0x10)
level |= 0x01;
// -- todo: save to property "bklt"
}
return rc;
}
int __pmac set_backlight_level(int level)
{
if (!backlighter)
return -ENODEV;
backlight_req_level = level;
schedule_work(&backlight_work);
return 0;
}
EXPORT_SYMBOL(set_backlight_level);
int __pmac get_backlight_level(void)
{
if (!backlighter)
return -ENODEV;
return backlight_level;
}
EXPORT_SYMBOL(get_backlight_level);
static void backlight_callback(void *dummy)
{
int level, enable;
do {
level = backlight_req_level;
enable = backlight_req_enable;
mb();
if (level >= 0)
__set_backlight_level(level);
if (enable >= 0)
__set_backlight_enable(enable);
} while(cmpxchg(&backlight_req_level, level, -1) != level ||
cmpxchg(&backlight_req_enable, enable, -1) != enable);
}