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

From: Dmitry Torokhov
Date: Tue Feb 28 2012 - 19:13:07 EST


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@xxxxxxx>
> 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@xxxxxxx>
> ---
> 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
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