Re: [PATCH 1/2] ACPI video: Harden video bus adding.

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Igor,

On Wed, Feb 29, 2012 at 03:51:42AM +0400, Igor Murzov wrote:
> From 127b9fc18ee646d92039c45d7fa3680a107928a2 Mon Sep 17 00:00:00 2001
> From: Igor Murzov <e-mail@date.by>
> Date: Mon, 27 Feb 2012 21:50:17 +0400
> Subject: [PATCH 1/2] ACPI video: Harden video bus adding.
> 
> It is always better to check return values.
> 
> Signed-off-by: Igor Murzov <e-mail@date.by>
> ---
>  drivers/acpi/video.c |   28 +++++++++++++++++++---------
>  1 files changed, 19 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index eaef02a..1bc6370 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -548,24 +548,25 @@ acpi_video_device_EDID(struct acpi_video_device *device,
>   *		1. 	The system BIOS should NOT automatically control the brightness 
>   *			level of the LCD when the power changes from AC to DC.
>   * Return Value:
> - * 		-1	wrong arg.
> + * 		-EINVAL	wrong arg.
>   */
>  
>  static int
>  acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
>  {
> -	u64 status = 0;
> +	int status = 0;
>  	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
>  	struct acpi_object_list args = { 1, &arg0 };
>  
>  
>  	if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1) {
> -		status = -1;
> +		status = -EINVAL;
>  		goto Failed;
>  	}
>  	arg0.integer.value = (lcd_flag << 2) | bios_flag;
>  	video->dos_setting = arg0.integer.value;
> -	acpi_evaluate_object(video->device->handle, "_DOS", &args, NULL);
> +	status = acpi_evaluate_object(video->device->handle, "_DOS",
> +	                              &args, NULL);

Here (as well as in the rest of your patch) you are mixing up errors
from the standard Unix -E* namespace and ACPI AE_* namespace. You need
to settle on one and be consistent (and also make sure that upper layers
get wha they expect, namely -E* namespace).

Thanks.

-- 
Dmitry