toshiba_acpi: Fix regression caused by backlight extra check code

Bug 86521 uncovered that some TOS6208 devices also return
non zero values on a write call to the backlight method,
thus getting caught and bailed out by the extra check code.

This patch changes the set_lcd_brightness function to its
"original" state by just adapting it to the new function
format.

Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

1 files changed, 4 insertions, 17 deletions

diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 96076d99cf33..06362b7d3ad7 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -928,9 +928,7 @@ static int lcd_proc_open(struct inode *inode, struct file *file)
 
 static int set_lcd_brightness(struct toshiba_acpi_dev *dev, int value)
 {
-        u32 in[TCI_WORDS] = { HCI_SET, HCI_LCD_BRIGHTNESS, 0, 0, 0, 0 };
-        u32 out[TCI_WORDS];
-        acpi_status status;
+        u32 hci_result;
 
         if (dev->tr_backlight_supported) {
                 bool enable = !value;
@@ -941,20 +939,9 @@ static int set_lcd_brightness(struct toshiba_acpi_dev *dev, int value)
                         value--;
         }
 
-        in[2] = value << HCI_LCD_BRIGHTNESS_SHIFT;
-        status = tci_raw(dev, in, out);
-        if (ACPI_FAILURE(status) || out[0] == TOS_FAILURE) {
-                pr_err("ACPI call to set brightness failed");
-                return -EIO;
-        }
-        /* Extra check for "incomplete" backlight method, where the AML code
-         * doesn't check for HCI_SET or HCI_GET and returns TOS_SUCCESS,
-         * the actual brightness, and in some cases the max brightness.
-         */
-        if (out[2] > 0  || out[3] == 0xE000)
-                return -ENODEV;
-
-        return out[0] == TOS_SUCCESS ? 0 : -EIO;
+        value = value << HCI_LCD_BRIGHTNESS_SHIFT;
+        hci_result = hci_write1(dev, HCI_LCD_BRIGHTNESS, value);
+        return hci_result == TOS_SUCCESS ? 0 : -EIO;
 }
 
 static int set_lcd_status(struct backlight_device *bd)