[PATCH 2/2] drm/radeon/kms: Use the standard VESA timeout for DDC channels

[Alex Deucher]

On Sat, Jan 28, 2012 at 5:08 AM, Jean Delvare <jdelvare at suse.de> wrote:
> The VESA specification suggests a 2.2 ms timeout on DDC channels.
> Use exactly that (as the i915 driver does) instead of hard-coding a
> jiffy count.
>
> Signed-off-by: Jean Delvare <jdelvare at suse.de>
> Reviewed-by: Keith Packard <keithp at keithp.com>
> Cc: Dave Airlie <airlied at gmail.com>
> Cc: Alex Deucher <alexdeucher at gmail.com>

Reviewed-by: Alex Deucher <alexdeucher at gmail.com>

> ---
> Already sent on: 2011-10-21.
>
>  drivers/gpu/drm/radeon/radeon_i2c.c |    4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> --- linux-3.3-rc1.orig/drivers/gpu/drm/radeon/radeon_i2c.c      2012-01-28 10:37:51.722069517 +0100
> +++ linux-3.3-rc1/drivers/gpu/drm/radeon/radeon_i2c.c   2012-01-28 10:39:26.996070929 +0100
> @@ -925,9 +925,7 @@ struct radeon_i2c_chan *radeon_i2c_creat
>                i2c->algo.bit.getsda = get_data;
>                i2c->algo.bit.getscl = get_clock;
>                i2c->algo.bit.udelay = 10;
> -               /* vesa says 2.2 ms is enough, 1 jiffy doesn't seem to always
> -                * make this, 2 jiffies is a lot more reliable */
> -               i2c->algo.bit.timeout = 2;
> +               i2c->algo.bit.timeout = usecs_to_jiffies(2200); /* from VESA */
>                i2c->algo.bit.data = i2c;
>                ret = i2c_bit_add_bus(&i2c->adapter);
>                if (ret) {
>
> --
> Jean Delvare
> Suse L3