diff options
Diffstat (limited to 'drivers/video/backlight/corgi_bl.c')
| -rw-r--r-- | drivers/video/backlight/corgi_bl.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/video/backlight/corgi_bl.c b/drivers/video/backlight/corgi_bl.c new file mode 100644 index 000000000000..3c026b036c86 --- /dev/null +++ b/drivers/video/backlight/corgi_bl.c @@ -0,0 +1,198 @@ +/* + * Backlight Driver for Sharp Corgi + * + * Copyright (c) 2004-2005 Richard Purdie + * + * Based on Sharp's 2.4 Backlight Driver + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/spinlock.h> +#include <linux/fb.h> +#include <linux/backlight.h> + +#include <asm/arch-pxa/corgi.h> +#include <asm/hardware/scoop.h> + +#define CORGI_MAX_INTENSITY 0x3e +#define CORGI_DEFAULT_INTENSITY 0x1f +#define CORGI_LIMIT_MASK 0x0b + +static int corgibl_powermode = FB_BLANK_UNBLANK; +static int current_intensity = 0; +static int corgibl_limit = 0; +static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED; + +static void corgibl_send_intensity(int intensity) +{ + unsigned long flags; + void (*corgi_kick_batt)(void); + + if (corgibl_powermode != FB_BLANK_UNBLANK) { + intensity = 0; + } else { + if (corgibl_limit) + intensity &= CORGI_LIMIT_MASK; + } + + /* Skip 0x20 as it will blank the display */ + if (intensity >= 0x20) + intensity++; + + spin_lock_irqsave(&bl_lock, flags); + /* Bits 0-4 are accessed via the SSP interface */ + corgi_ssp_blduty_set(intensity & 0x1f); + /* Bit 5 is via SCOOP */ + if (intensity & 0x0020) + set_scoop_gpio(&corgiscoop_device.dev, CORGI_SCP_BACKLIGHT_CONT); + else + reset_scoop_gpio(&corgiscoop_device.dev, CORGI_SCP_BACKLIGHT_CONT); + spin_unlock_irqrestore(&bl_lock, flags); +} + +static void corgibl_blank(int blank) +{ + switch(blank) { + + case FB_BLANK_NORMAL: + case FB_BLANK_VSYNC_SUSPEND: + case FB_BLANK_HSYNC_SUSPEND: + case FB_BLANK_POWERDOWN: + if (corgibl_powermode == FB_BLANK_UNBLANK) { + corgibl_send_intensity(0); + corgibl_powermode = blank; + } + break; + case FB_BLANK_UNBLANK: + if (corgibl_powermode != FB_BLANK_UNBLANK) { + corgibl_powermode = blank; + corgibl_send_intensity(current_intensity); + } + break; + } +} + +#ifdef CONFIG_PM +static int corgibl_suspend(struct device *dev, u32 state, u32 level) +{ + if (level == SUSPEND_POWER_DOWN) + corgibl_blank(FB_BLANK_POWERDOWN); + return 0; +} + +static int corgibl_resume(struct device *dev, u32 level) +{ + if (level == RESUME_POWER_ON) + corgibl_blank(FB_BLANK_UNBLANK); + return 0; +} +#else +#define corgibl_suspend NULL +#define corgibl_resume NULL +#endif + + +static int corgibl_set_power(struct backlight_device *bd, int state) +{ + corgibl_blank(state); + return 0; +} + +static int corgibl_get_power(struct backlight_device *bd) +{ + return corgibl_powermode; +} + +static int corgibl_set_intensity(struct backlight_device *bd, int intensity) +{ + if (intensity > CORGI_MAX_INTENSITY) + intensity = CORGI_MAX_INTENSITY; + corgibl_send_intensity(intensity); + current_intensity=intensity; + return 0; +} + +static int corgibl_get_intensity(struct backlight_device *bd) +{ + return current_intensity; +} + +/* + * Called when the battery is low to limit the backlight intensity. + * If limit==0 clear any limit, otherwise limit the intensity + */ +void corgibl_limit_intensity(int limit) +{ + corgibl_limit = (limit ? 1 : 0); + corgibl_send_intensity(current_intensity); +} +EXPORT_SYMBOL(corgibl_limit_intensity); + + +static struct backlight_properties corgibl_data = { + .owner = THIS_MODULE, + .get_power = corgibl_get_power, + .set_power = corgibl_set_power, + .max_brightness = CORGI_MAX_INTENSITY, + .get_brightness = corgibl_get_intensity, + .set_brightness = corgibl_set_intensity, +}; + +static struct backlight_device *corgi_backlight_device; + +static int __init corgibl_probe(struct device *dev) +{ + corgi_backlight_device = backlight_device_register ("corgi-bl", + NULL, &corgibl_data); + if (IS_ERR (corgi_backlight_device)) + return PTR_ERR (corgi_backlight_device); + + corgibl_set_intensity(NULL, CORGI_DEFAULT_INTENSITY); + + printk("Corgi Backlight Driver Initialized.\n"); + return 0; +} + +static int corgibl_remove(struct device *dev) +{ + backlight_device_unregister(corgi_backlight_device); + + corgibl_set_intensity(NULL, 0); + + printk("Corgi Backlight Driver Unloaded\n"); + return 0; +} + +static struct device_driver corgibl_driver = { + .name = "corgi-bl", + .bus = &platform_bus_type, + .probe = corgibl_probe, + .remove = corgibl_remove, + .suspend = corgibl_suspend, + .resume = corgibl_resume, +}; + +static int __init corgibl_init(void) +{ + return driver_register(&corgibl_driver); +} + +static void __exit corgibl_exit(void) +{ + driver_unregister(&corgibl_driver); +} + +module_init(corgibl_init); +module_exit(corgibl_exit); + +MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>"); +MODULE_DESCRIPTION("Corgi Backlight Driver"); +MODULE_LICENSE("GPLv2"); |