ACPI: asus_acpi: Add support for the generic backlight device

Add support for the generic backlight interface below /sys/class/backlight.
Keep the procfs brightness handling for backward compatibility.

[apw@shadowen.org: backlight users need to select BACKLIGHT_CLASS_DEVICE]

Signed-off-by: Holger Macht <hmacht@suse.de>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index bc58a3b18e06cf1ebfdd594f2eb670e144b12ade..9b64c4e6c63e23c96620b1ab79511004fa8e98fa 100644 (file)
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -172,6 +172,7 @@ config ACPI_NUMA
 config ACPI_ASUS
         tristate "ASUS/Medion Laptop Extras"
        depends on X86
+       select BACKLIGHT_CLASS_DEVICE
         ---help---
           This driver provides support for extra features of ACPI-compatible
           ASUS laptops. As some of Medion laptops are made by ASUS, it may also

diff --git a/drivers/acpi/asus_acpi.c b/drivers/acpi/asus_acpi.c
index c7ac9297a20499893da15a4f2c766285310d6f1b..bf7bc25e680efa6e53d863b26a51608f122cd8ea 100644 (file)
--- a/drivers/acpi/asus_acpi.c
+++ b/drivers/acpi/asus_acpi.c
@@ -35,6 +35,7 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/proc_fs.h>
+#include <linux/backlight.h>
 #include <acpi/acpi_drivers.h>
 #include <acpi/acpi_bus.h>
 #include <asm/uaccess.h>
@@ -402,6 +403,8 @@ static struct model_data model_conf[END_MODEL] = {
 /* procdir we use */
 static struct proc_dir_entry *asus_proc_dir;
 
+static struct backlight_device *asus_backlight_device;
+
 /*
  * This header is made available to allow proper configuration given model,
  * revision number , ... this info cannot go in struct asus_hotk because it is
@@ -779,7 +782,7 @@ proc_write_lcd(struct file *file, const char __user * buffer,
        return rv;
 }
 
-static int read_brightness(void)
+static int read_brightness(struct backlight_device *bd)
 {
        int value;
 
@@ -801,9 +804,10 @@ static int read_brightness(void)
 /*
  * Change the brightness level
  */
-static void set_brightness(int value)
+static int set_brightness(int value)
 {
        acpi_status status = 0;
+       int ret = 0;
 
        /* SPLV laptop */
        if (hotk->methods->brightness_set) {
@@ -811,11 +815,12 @@ static void set_brightness(int value)
                                    value, NULL))
                        printk(KERN_WARNING
                               "Asus ACPI: Error changing brightness\n");
-               return;
+                       ret = -EIO;
+               goto out;
        }
 
        /* No SPLV method if we are here, act as appropriate */
-       value -= read_brightness();
+       value -= read_brightness(NULL);
        while (value != 0) {
                status = acpi_evaluate_object(NULL, (value > 0) ?
                                              hotk->methods->brightness_up :
@@ -825,15 +830,22 @@ static void set_brightness(int value)
                if (ACPI_FAILURE(status))
                        printk(KERN_WARNING
                               "Asus ACPI: Error changing brightness\n");
+                       ret = -EIO;
        }
-       return;
+out:
+       return ret;
+}
+
+static int set_brightness_status(struct backlight_device *bd)
+{
+       return set_brightness(bd->props->brightness);
 }
 
 static int
 proc_read_brn(char *page, char **start, off_t off, int count, int *eof,
              void *data)
 {
-       return sprintf(page, "%d\n", read_brightness());
+       return sprintf(page, "%d\n", read_brightness(NULL));
 }
 
 static int
@@ -1333,6 +1345,26 @@ static int asus_hotk_remove(struct acpi_device *device, int type)
        return 0;
 }
 
+static struct backlight_properties asus_backlight_data = {
+        .owner          = THIS_MODULE,
+        .get_brightness = read_brightness,
+        .update_status  = set_brightness_status,
+        .max_brightness = 15,
+};
+
+static void __exit asus_acpi_exit(void)
+{
+       if (asus_backlight_device)
+               backlight_device_unregister(asus_backlight_device);
+
+       acpi_bus_unregister_driver(&asus_hotk_driver);
+       remove_proc_entry(PROC_ASUS, acpi_root_dir);
+
+       kfree(asus_info);
+
+       return;
+}
+
 static int __init asus_acpi_init(void)
 {
        int result;
@@ -1370,17 +1402,15 @@ static int __init asus_acpi_init(void)
                return result;
        }
 
-       return 0;
-}
-
-static void __exit asus_acpi_exit(void)
-{
-       acpi_bus_unregister_driver(&asus_hotk_driver);
-       remove_proc_entry(PROC_ASUS, acpi_root_dir);
-
-       kfree(asus_info);
+       asus_backlight_device = backlight_device_register("asus", NULL,
+                                                         &asus_backlight_data);
+        if (IS_ERR(asus_backlight_device)) {
+               printk(KERN_ERR "Could not register asus backlight device\n");
+               asus_backlight_device = NULL;
+               asus_acpi_exit();
+       }
 
-       return;
+       return 0;
 }
 
 module_init(asus_acpi_init);