Commit 6b7091e7 authored by Corentin Chary's avatar Corentin Chary Committed by Len Brown
Browse files

asus-laptop: add backlight support



Adds backlight support using backlight class. We now
change the brightness *and toggle the backlight !* via
/sys/class/backlight/asus-laptop/.

If the user switchs the backlight using the keyboard,
asus_hotk_notify looks for ATKD_LCD_OFF and ATKD_LCD_ON events,
and stores the right state into hotk->status and bd->props->power .

Signed-off-by: default avatarCorentin Chary <corentincj@iksaif.net>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 4564de17
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+1 −0
Original line number Diff line number Diff line
@@ -75,6 +75,7 @@ config ASUS_LAPTOP
        depends on ACPI
	depends on EXPERIMENTAL && !ACPI_ASUS
	depends on LEDS_CLASS
	depends on BACKLIGHT_CLASS_DEVICE
        ---help---
	  This is the new Linux driver for Asus laptops. It may also support some
	  MEDION, JVC or VICTOR laptops. It makes all the extra buttons generate
+182 −1
Original line number Diff line number Diff line
@@ -40,6 +40,8 @@
#include <linux/types.h>
#include <linux/err.h>
#include <linux/proc_fs.h>
#include <linux/backlight.h>
#include <linux/fb.h>
#include <linux/leds.h>
#include <linux/platform_device.h>
#include <acpi/acpi_drivers.h>
@@ -55,6 +57,14 @@
#define ASUS_HOTK_FILE          "asus-laptop"
#define ASUS_HOTK_PREFIX        "\\_SB.ATKD."

/*
 * Some events we use, same for all Asus
 */
#define ATKD_BR_UP       0x10
#define ATKD_BR_DOWN     0x20
#define ATKD_LCD_ON      0x33
#define ATKD_LCD_OFF     0x34

/*
 * Known bits returned by \_SB.ATKD.HWRS
 */
@@ -71,6 +81,7 @@
#define TLED_ON     0x08	//touchpad LED
#define RLED_ON     0x10        //Record LED
#define PLED_ON     0x20        //Phone LED
#define LCD_ON      0x40        //LCD backlight

#define ASUS_LOG    ASUS_HOTK_FILE ": "
#define ASUS_ERR    KERN_ERR    ASUS_LOG
@@ -101,6 +112,19 @@ ASUS_HANDLE(wl_switch, ASUS_HOTK_PREFIX "WLED");
ASUS_HANDLE(bt_switch, ASUS_HOTK_PREFIX "BLED");
ASUS_HANDLE(wireless_status, ASUS_HOTK_PREFIX "RSTS"); /* All new models */

/* Brightness */
ASUS_HANDLE(brightness_set, ASUS_HOTK_PREFIX "SPLV");
ASUS_HANDLE(brightness_get, ASUS_HOTK_PREFIX "GPLV");

/* Backlight */
ASUS_HANDLE(lcd_switch, "\\_SB.PCI0.SBRG.EC0._Q10", /* All new models */
	    "\\_SB.PCI0.ISA.EC0._Q10", /* A1x */
	    "\\_SB.PCI0.PX40.ECD0._Q10", /* L3C */
	    "\\_SB.PCI0.PX40.EC0.Q10", /* M1A */
	    "\\_SB.PCI0.LPCB.EC0._Q10", /* P30 */
	    "\\_SB.PCI0.PX40.Q10", /* S1x */
	    "\\Q10");  /* A2x, L2D, L3D, M2E */

/*
 * This is the main structure, we can use it to store anything interesting
 * about the hotk device
@@ -138,6 +162,21 @@ static struct acpi_driver asus_hotk_driver = {
		},
};

/* The backlight device /sys/class/backlight */
static struct backlight_device *asus_backlight_device;

/*
 * The backlight class declaration
 */
static int read_brightness(struct backlight_device *bd);
static int update_bl_status(struct backlight_device *bd);
static struct backlight_properties asusbl_data = {
	       .owner          = THIS_MODULE,
	       .get_brightness = read_brightness,
	       .update_status  = update_bl_status,
	       .max_brightness = 15,
};

/* These functions actually update the LED's, and are called from a
 * workqueue. By doing this as separate work rather than when the LED
 * subsystem asks, we avoid messing with the Asus ACPI stuff during a
@@ -253,6 +292,86 @@ ASUS_LED_HANDLER(pled, PLED_ON, 0);
ASUS_LED_HANDLER(rled, RLED_ON, 0);
ASUS_LED_HANDLER(tled, TLED_ON, 0);

static int get_lcd_state(void)
{
	return read_status(LCD_ON);
}

static int set_lcd_state(int value)
{
	int lcd = 0;
	acpi_status status = 0;

	lcd = value ? 1 : 0;

	if (lcd == get_lcd_state())
		return 0;

	if(lcd_switch_handle) {
		status = acpi_evaluate_object(lcd_switch_handle,
					      NULL, NULL, NULL);

		if (ACPI_FAILURE(status))
			printk(ASUS_WARNING "Error switching LCD\n");
	}

	write_status(NULL, lcd, LCD_ON, 0);
	return 0;
}

static void lcd_blank(int blank)
{
	struct backlight_device *bd = asus_backlight_device;

	if(bd) {
		down(&bd->sem);
		if(likely(bd->props)) {
			bd->props->power = blank;
			if(likely(bd->props->update_status))
			   bd->props->update_status(bd);
		}
		up(&bd->sem);
	}
}

static int read_brightness(struct backlight_device *bd)
{
	int value;

	if (!read_acpi_int(brightness_get_handle, NULL, &value, NULL))
		printk(ASUS_WARNING "Error reading brightness\n");

	return value;
}

static int set_brightness(struct backlight_device *bd, int value)
{
	int ret = 0;

	value = (0 < value) ? ((15 < value) ? 15 : value) : 0;
	/* 0 <= value <= 15 */

	if (!write_acpi_int(brightness_set_handle, NULL, value, NULL)) {
		printk(ASUS_WARNING "Error changing brightness\n");
		ret = -EIO;
	}

	return ret;
}

static int update_bl_status(struct backlight_device *bd)
{
	int rv;
	int value = bd->props->brightness;

	rv = set_brightness(bd, value);
	if(rv)
		return rv;

	value = (bd->props->power == FB_BLANK_UNBLANK) ? 1 : 0;
	return set_lcd_state(value);
}

/*
 * Platform device handlers
 */
@@ -378,6 +497,18 @@ static void asus_hotk_notify(acpi_handle handle, u32 event, void *data)
	if (!hotk)
		return;

	/*
	 * We need to tell the backlight device when the backlight power is
	 * switched
	 */
	if (event == ATKD_LCD_ON) {
		write_status(NULL, 1, LCD_ON, 0);
		lcd_blank(FB_BLANK_UNBLANK);
	} else if(event == ATKD_LCD_OFF) {
		write_status(NULL, 0, LCD_ON, 0);
		lcd_blank(FB_BLANK_POWERDOWN);
	}

	acpi_bus_generate_event(hotk->device, event,
				hotk->event_count[event % 128]++);

@@ -547,6 +678,11 @@ static int asus_hotk_get_info(void)

	ASUS_HANDLE_INIT(wireless_status);

	ASUS_HANDLE_INIT(brightness_set);
	ASUS_HANDLE_INIT(brightness_get);

	ASUS_HANDLE_INIT(lcd_switch);

	kfree(model);

	return AE_OK;
@@ -615,6 +751,9 @@ static int asus_hotk_add(struct acpi_device *device)
	write_status(bt_switch_handle, 1, BT_ON, 0);
	write_status(wl_switch_handle, 1, WL_ON, 0);

	/* LCD Backlight is on by default */
	write_status(NULL, 1, LCD_ON, 0);

      end:
	if (result) {
		kfree(hotk->name);
@@ -642,6 +781,12 @@ static int asus_hotk_remove(struct acpi_device *device, int type)
	return 0;
}

static void asus_backlight_exit(void)
{
	if(asus_backlight_device)
		backlight_device_unregister(asus_backlight_device);
}

#define  ASUS_LED_UNREGISTER(object)				\
	if(object##_led.class_dev				\
	   && !IS_ERR(object##_led.class_dev))			\
@@ -659,6 +804,7 @@ static void asus_led_exit(void)

static void __exit asus_laptop_exit(void)
{
	asus_backlight_exit();
	asus_led_exit();

	acpi_bus_unregister_driver(&asus_hotk_driver);
@@ -669,6 +815,34 @@ static void __exit asus_laptop_exit(void)
	kfree(asus_info);
}

static int asus_backlight_init(struct device * dev)
{
	struct backlight_device *bd;

	if(brightness_set_handle && lcd_switch_handle) {
		bd = backlight_device_register (ASUS_HOTK_FILE, dev,
						NULL, &asusbl_data);
		if (IS_ERR (bd)) {
			printk(ASUS_ERR
			       "Could not register asus backlight device\n");
			asus_backlight_device = NULL;
			return PTR_ERR(bd);
		}

		asus_backlight_device = bd;

		down(&bd->sem);
		if(likely(bd->props)) {
			bd->props->brightness = read_brightness(NULL);
			bd->props->power = FB_BLANK_UNBLANK;
			if(likely(bd->props->update_status))
			   bd->props->update_status(bd);
		}
		up(&bd->sem);
	}
	return 0;
}

static int asus_led_register(acpi_handle handle,
			     struct led_classdev * ldev,
			     struct device * dev)
@@ -739,6 +913,10 @@ static int __init asus_laptop_init(void)

	dev = acpi_get_physical_device(hotk->device->handle);

	result = asus_backlight_init(dev);
	if(result)
		goto fail_backlight;

	result = asus_led_init(dev);
	if(result)
		goto fail_led;
@@ -778,6 +956,9 @@ fail_platform_driver:
	asus_led_exit();

fail_led:
	asus_backlight_exit();

fail_backlight:

	return result;
}