[PATCH] Add generic backlight support to toshiba_acpi driver

[PATCH] Add generic backlight support to toshiba_acpi driver

[Matthew Garrett]

The included patch adds support for interacting with the toshiba_acpi 
backlight control through the generic backlight interface 
(/sys/class/backlight).

ACPI folk: this gives us the benefit of a consistent interface to LCD 
brightness. Is it worth me converting the other drivers over?

Signed-Off-By: Matthew Garrett <mjg59@srcf.ucam.org>

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 5243f0c..69ed5c2 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -215,7 +215,7 @@ config ACPI_IBM
 
 config ACPI_TOSHIBA
 	tristate "Toshiba Laptop Extras"
-	depends on X86
+	depends on X86 && BACKLIGHT_DEVICE
 	default y
 	---help---
 	  This driver adds support for access to certain system settings
diff --git a/drivers/acpi/toshiba_acpi.c b/drivers/acpi/toshiba_acpi.c
index b2fa688..f263f62 100644
--- a/drivers/acpi/toshiba_acpi.c
+++ b/drivers/acpi/toshiba_acpi.c
@@ -60,6 +60,7 @@
 #include <linux/suspend.h>
 #include <linux/miscdevice.h>
 #include <linux/toshiba.h>
+#include <linux/backlight.h>
 #include <asm/io.h>
 #include <asm/uaccess.h>
 
@@ -117,6 +118,8 @@ MODULE_LICENSE("GPL");
 #define HCI_VIDEO_OUT_CRT		0x2
 #define HCI_VIDEO_OUT_TV		0x4
 
+static struct backlight_device *tosh_backlight_device;
+
 /* utility
  */
 
@@ -315,6 +318,19 @@ static char *read_lcd(char *p)
 	return p;
 }
 
+static int tosh_get_brightness(struct backlight_device *bd)
+{
+	int brightness;
+	u32 hci_result;
+
+	hci_read1(HCI_LCD_BRIGHTNESS, &brightness, &hci_result);
+	if (hci_result == HCI_SUCCESS) {
+		brightness = brightness >> HCI_LCD_BRIGHTNESS_SHIFT;
+		return brightness;
+	} else
+		return 0;
+}
+
 static unsigned long write_lcd(const char *buffer, unsigned long count)
 {
 	int value;
@@ -333,6 +349,22 @@ static unsigned long write_lcd(const cha
 	return count;
 }
 
+static int tosh_set_brightness(struct backlight_device *bd, int brightness)
+{
+	u32 hci_result;
+
+	if (brightness >= 0 && brightness < HCI_LCD_BRIGHTNESS_LEVELS) {
+		brightness= brightness << HCI_LCD_BRIGHTNESS_SHIFT;
+		hci_write1(HCI_LCD_BRIGHTNESS, brightness, &hci_result);
+		if (hci_result != HCI_SUCCESS)
+			return -EFAULT;
+	} else {
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static char *read_video(char *p)
 {
 	u32 hci_result;
@@ -588,6 +620,13 @@ static struct miscdevice tosh_device = {
 	&tosh_fops
 };
 
+static struct backlight_properties toshbl_data = {
+	.owner          = THIS_MODULE,
+	.get_brightness = tosh_get_brightness,
+	.set_brightness = tosh_set_brightness,
+	.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS,
+};
+
 static void
 setup_tosh_info(void)
 {
@@ -891,6 +930,12 @@ static int __init toshiba_acpi_init(void
 		}
 	}
 
+	tosh_backlight_device = backlight_device_register ("tosh-bl", NULL,
+							   &toshbl_data);
+
+	if (IS_ERR (tosh_backlight_device))
+		printk("Failed to register Toshiba backlight device\n");
+
 	return (ACPI_SUCCESS(status)) ? 0 : -ENODEV;
 }
 
@@ -909,6 +954,8 @@ static void __exit toshiba_acpi_exit(voi
 
 	old_driver_emulation_exit();
 
+	backlight_device_unregister(tosh_backlight_device);
+
 	printk(MY_INFO "Toshiba Laptop ACPI Extras unloaded\n");
 
 	return;

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] Add generic backlight support to toshiba_acpi driver

[Pavel Machek]

Hi!

> The included patch adds support for interacting with the toshiba_acpi 
> backlight control through the generic backlight interface 
> (/sys/class/backlight).
> 
> ACPI folk: this gives us the benefit of a consistent interface to LCD 
> brightness. Is it worth me converting the other drivers over?

Not sure if I'm ACPI folk but yes, consistent interface would be nice.

								Pavel

-- 
Web maintainer for suspend.sf.net (www.sf.net/projects/suspend) wanted...

Re: [PATCH] Add generic backlight support to toshiba_acpi driver

[Jan Engelhardt]

>> The included patch adds support for interacting with the toshiba_acpi 
>> backlight control through the generic backlight interface 
>> (/sys/class/backlight).
>> 
>> ACPI folk: this gives us the benefit of a consistent interface to LCD 
>> brightness. Is it worth me converting the other drivers over?
>
>Not sure if I'm ACPI folk but yes, consistent interface would be nice.
>
Note to self: Don't forget to change 2.6-sony-acpi?.diff from -mm to use 
this /sys/class/backlight instead of /proc/acpi/sony/brightness when it's 
ready.


Jan Engelhardt
-- 

Re: [PATCH] Add generic backlight support to toshiba_acpi driver

[Matthew Garrett]

On Thu, Feb 09, 2006 at 05:47:49PM +0100, Jan Engelhardt wrote:

> Note to self: Don't forget to change 2.6-sony-acpi?.diff from -mm to use 
> this /sys/class/backlight instead of /proc/acpi/sony/brightness when it's 
> ready.

Ah, you're maintaining that now. Here you go (Stelian took a look and 
seemed happy with it - the /sys/class/backlight stuff is in mainstream)

diff --git a/drivers/acpi/sony_acpi.c b/drivers/acpi/sony_acpi.c
index 7636bba..6505b24 100644
--- a/drivers/acpi/sony_acpi.c
+++ b/drivers/acpi/sony_acpi.c
@@ -27,6 +27,8 @@
 #include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/types.h>
+#include <linux/backlight.h>
+#include <linux/err.h>
 #include <acpi/acpi_drivers.h>
 #include <acpi/acpi_bus.h>
 #include <asm/uaccess.h>
@@ -62,6 +64,8 @@ static struct acpi_driver sony_acpi_driv
 static acpi_handle sony_acpi_handle;
 static struct proc_dir_entry *sony_acpi_dir;
 
+static struct backlight_device *sony_backlight_device;
+
 static struct sony_acpi_value {
 	char			*name;	 /* name of the entry */
 	struct proc_dir_entry 	*proc;	 /* /proc entry */
@@ -258,6 +262,31 @@ static acpi_status sony_walk_callback(ac
 	return AE_OK;
 }
 
+static int sony_brightness_get(struct backlight_device *bd) 
+{
+	int value;
+
+	if (acpi_callgetfunc(sony_acpi_handle, "GBRT", &value))
+		return 0;
+
+	return value-1;
+}
+	
+
+static int sony_brightness_set(struct backlight_device *bd, int value) {
+	value &= 0x7;
+	value++;
+
+	return acpi_callsetfunc(sony_acpi_handle, "SBRT", value, NULL);
+}
+
+static struct backlight_properties sonybl_data = {
+	.owner          = THIS_MODULE,
+	.get_brightness = sony_brightness_get,
+	.set_brightness = sony_brightness_set,
+	.max_brightness = 7,
+};
+
 static int __init sony_acpi_add(struct acpi_device *device)
 {
 	acpi_status status;
@@ -378,12 +407,24 @@ static int __init sony_acpi_init(void)
 		remove_proc_entry("sony", acpi_root_dir);
 		return -ENODEV;
 	}
+
+	sony_backlight_device = backlight_device_register ("sony_bl", NULL,
+							   &sonybl_data);
+
+	if (IS_ERR (sony_backlight_device)) {
+		printk("Unable to register backlight\n");
+		acpi_bus_unregister_driver(&sony_acpi_driver);
+		remove_proc_entry("sony", acpi_root_dir);
+		return -ENODEV;
+	}
+
 	return 0;
 }
 
 
 static void __exit sony_acpi_exit(void)
 {
+	backlight_device_unregister(sony_backlight_device);
 	acpi_bus_unregister_driver(&sony_acpi_driver);
 	remove_proc_entry("sony", acpi_root_dir);
 }

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] Add generic backlight support to toshiba_acpi driver

[Jan Engelhardt]

>
>> Note to self: Don't forget to change 2.6-sony-acpi?.diff from -mm to use 
>> this /sys/class/backlight instead of /proc/acpi/sony/brightness when it's 
>> ready.
>
>Ah, you're maintaining that now. Here you go (Stelian took a look and 
>seemed happy with it - the /sys/class/backlight stuff is in mainstream)
>
Well, I am not. At least not-yet-officially. But since I happen to have 
that hardware, I use it. (And I even have to postpatch the SUSE KOTD ATM
to get there, heh, heh.)



Jan Engelhardt
-- 

Re: [PATCH] Add generic backlight support to toshiba_acpi driver

[Ben Slusky]

On Tue, 07 Feb 2006 13:34:56 +0000, Matthew Garrett wrote:
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -215,7 +215,7 @@ config ACPI_IBM
>  
>  config ACPI_TOSHIBA
>  	tristate "Toshiba Laptop Extras"
> -	depends on X86
> +	depends on X86 && BACKLIGHT_DEVICE
>  	default y
>  	---help---
>  	  This driver adds support for access to certain system settings

Might this work better:

	config ACPI_TOSHIBA
		depends on X86
		select BACKLIGHT_DEVICE

-
-Ben


-- 
Ben Slusky                  | It was only after their population
sluskyb@paranoiacs.org      | of 50 mysteriously shrank to eight
sluskyb@stwing.org          | that the other seven dwarfs began
PGP keyID ADA44B3B          | to suspect Hungry.