sony_acpi: Add backlight support to the sony_acpi

Make the sony_acpi use the backlight subsystem to adjust brightness value
instead of using the /proc/sony/brightness file.  (Other settings will
still have a /proc/sony/...  entry)

Signed-off-by: Alessandro Guido <alessandro.guido@gmail.com>
Cc: Stelian Pop <stelian@popies.net>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mattia Dongili <malattia@linux.it>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index e11371f..364e6fe 100644 (file)
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -255,6 +255,7 @@ config ACPI_TOSHIBA
 config ACPI_SONY
        tristate "Sony Laptop Extras"
        depends on X86 && ACPI
+       select BACKLIGHT_CLASS_DEVICE
        default m
          ---help---
          This mini-driver drives the ACPI SNC device present in the

diff --git a/drivers/acpi/sony_acpi.c b/drivers/acpi/sony_acpi.c
index f323c2c..d509468 100644 (file)
--- a/drivers/acpi/sony_acpi.c
+++ b/drivers/acpi/sony_acpi.c
@@ -27,13 +27,19 @@
 #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>
 
 #define ACPI_SNC_CLASS         "sony"
 #define ACPI_SNC_HID           "SNY5001"
-#define ACPI_SNC_DRIVER_NAME   "ACPI Sony Notebook Control Driver v0.2"
+#define ACPI_SNC_DRIVER_NAME   "ACPI Sony Notebook Control Driver v0.3"
+
+/* the device uses 1-based values, while the backlight subsystem uses
+   0-based values */
+#define SONY_MAX_BRIGHTNESS    8
 
 #define LOG_PFX                        KERN_WARNING "sony_acpi: "
 
@@ -49,6 +55,16 @@ MODULE_PARM_DESC(debug, "set this to 1 (and RTFM) if you want to help "
 static acpi_handle sony_acpi_handle;
 static struct proc_dir_entry *sony_acpi_dir;
 
+static int sony_backlight_update_status(struct backlight_device *bd);
+static int sony_backlight_get_brightness(struct backlight_device *bd);
+static struct backlight_device *sony_backlight_device;
+static struct backlight_properties sony_backlight_properties = {
+       .owner          = THIS_MODULE,
+       .update_status  = sony_backlight_update_status,
+       .get_brightness = sony_backlight_get_brightness,
+       .max_brightness = SONY_MAX_BRIGHTNESS - 1,
+};
+
 static struct sony_acpi_value {
        char                    *name;   /* name of the entry */
        struct proc_dir_entry   *proc;   /* /proc entry */
@@ -60,20 +76,12 @@ static struct sony_acpi_value {
        int                     valid;   /* Has ever been set */
        int                     debug;   /* active only in debug mode ? */
 } sony_acpi_values[] = {
-       {
-               .name           = "brightness",
-               .acpiget        = "GBRT",
-               .acpiset        = "SBRT",
-               .min            = 1,
-               .max            = 8,
-               .debug          = 0,
-       },
        {
                .name           = "brightness_default",
                .acpiget        = "GPBR",
                .acpiset        = "SPBR",
                .min            = 1,
-               .max            = 8,
+               .max            = SONY_MAX_BRIGHTNESS,
                .debug          = 0,
        },
        {
@@ -276,6 +284,7 @@ static int sony_acpi_add(struct acpi_device *device)
 {
        acpi_status status;
        int result;
+       acpi_handle handle;
        struct sony_acpi_value *item;
 
        sony_acpi_handle = device->handle;
@@ -303,9 +312,15 @@ static int sony_acpi_add(struct acpi_device *device)
                }
        }
 
-       for (item = sony_acpi_values; item->name; ++item) {
-               acpi_handle handle;
+       if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle, "GBRT", &handle))) {
+               sony_backlight_device = backlight_device_register("sony", NULL,
+                                       &sony_backlight_properties);
+               if (IS_ERR(sony_backlight_device)) {
+                       printk(LOG_PFX "unable to register backlight device\n");
+               }
+       }
 
+       for (item = sony_acpi_values; item->name; ++item) {
                if (!debug && item->debug)
                        continue;
 
@@ -358,6 +373,9 @@ static int sony_acpi_remove(struct acpi_device *device, int type)
        acpi_status status;
        struct sony_acpi_value *item;
 
+       if (sony_backlight_device)
+               backlight_device_unregister(sony_backlight_device);
+
        if (debug) {
                status = acpi_remove_notify_handler(sony_acpi_handle,
                                                    ACPI_DEVICE_NOTIFY,
@@ -375,6 +393,23 @@ static int sony_acpi_remove(struct acpi_device *device, int type)
        return 0;
 }
 
+static int sony_backlight_update_status(struct backlight_device *bd)
+{
+       return acpi_callsetfunc(sony_acpi_handle, "SBRT",
+                               bd->props->brightness + 1,
+                               NULL);
+}
+
+static int sony_backlight_get_brightness(struct backlight_device *bd)
+{
+       int value;
+
+       if (acpi_callgetfunc(sony_acpi_handle, "GBRT", &value))
+               return 0;
+       /* brightness levels are 1-based, while backlight ones are 0-based */
+       return value - 1;
+}
+
 static struct acpi_driver sony_acpi_driver = {
        .name   = ACPI_SNC_DRIVER_NAME,
        .class  = ACPI_SNC_CLASS,