Yep. Good to go.
Reviewed-by: Todd Previte <tprev...@gmail.com>
On Fri, Sep 27, 2013 at 4:51 AM, Jani Nikula <jani.nik...@linux.intel.com>wrote:
> On Fri, 20 Sep 2013, Todd Previte <tprev...@gmail.com> wrote:
> > On 09/20/2013 06:42 AM, Jani Nikula wrote:
> >> Per DP1.2 spec.
> >>
> >> Signed-off-by: Jani Nikula <jani.nik...@intel.com>
> >> ---
> >> drivers/gpu/drm/i915/intel_dp.c | 7 ++++++-
> >> 1 file changed, 6 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c
> b/drivers/gpu/drm/i915/intel_dp.c
> >> index 9770160..6626514 100644
> >> --- a/drivers/gpu/drm/i915/intel_dp.c
> >> +++ b/drivers/gpu/drm/i915/intel_dp.c
> >> @@ -654,7 +654,12 @@ intel_dp_i2c_aux_ch(struct i2c_adapter *adapter,
> int mode,
> >> break;
> >> }
> >>
> >> - for (retry = 0; retry < 5; retry++) {
> >> + /*
> >> + * DP1.2 sections 2.7.7.1.5.6.1 and 2.7.7.1.6.6.1: A DP Source
> device is
> >> + * required to retry at least seven times upon receiving AUX_DEFER
> >> + * before giving up the AUX transaction.
> >> + */
> >> + for (retry = 0; retry < 7; retry++) {
> >> ret = intel_dp_aux_ch(intel_dp,
> >> msg, msg_bytes,
> >> reply, reply_bytes);
> >>
> > Hey Jani,
> >
> > Although it's not explicitly stated in the specification (I went through
> > both the 1.1a and 1.2a specifications and couldn't find it), I think the
> > the retry count of 7 applies to all AUX transactions, both native and
> > I2C. That's alluded to in the description of the link training sequence
> > (pg 382, 2nd paragraph from the bottom) where the sink may defer up to
> > seven times before the source can abort training.
> >
> > With that in mind, it might be a good idea to use a defined constant for
> > the retry count for both native and I2C AUX transactions. That would
> > keep it consistent throughout the code and be easier to update moving
> > forward should the specification change.
>
> Todd, are you willing to give your reviewed-by on this one patch per our
> irc discussion? We can do further cleanups later.
>
> I've sent a new version of 3/4 with the #defines separately.
>
>
> BR,
> Jani.
>
>
>
> --
> Jani Nikula, Intel Open Source Technology Center
>
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
