On Fri, 27 Jun 2025, Imre Deak <imre.d...@intel.com> wrote:
> On Fri, Jun 27, 2025 at 02:36:32PM +0300, Jani Nikula wrote:
>> Unify on using read_poll_timeout() throughout instead of mixing with
>> readx_poll_timeout(). While the latter can be ever so slightly simpler,
>> they are both complicated enough that it's better to unify on one
>> approach only.
>>
>> While at it, better separate the handling of error returns from
>> drm_dp_dpcd_readb() and the actual status byte. This is best achieved by
>> inlining the read_fec_detected_status() function.
>>
>> Cc: Imre Deak <imre.d...@intel.com>
>> Signed-off-by: Jani Nikula <jani.nik...@intel.com>
>> ---
>> drivers/gpu/drm/i915/display/intel_ddi.c | 33 +++++++++---------------
>> 1 file changed, 12 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c
>> b/drivers/gpu/drm/i915/display/intel_ddi.c
>> index 0405396c7750..fc4587311607 100644
>> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
>> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
>> @@ -2339,34 +2339,25 @@ static void intel_dp_sink_set_fec_ready(struct
>> intel_dp *intel_dp,
>> drm_dbg_kms(display->drm, "Failed to clear FEC detected
>> flags\n");
>> }
>>
>> -static int read_fec_detected_status(struct drm_dp_aux *aux)
>> -{
>> - int ret;
>> - u8 status;
>> -
>> - ret = drm_dp_dpcd_readb(aux, DP_FEC_STATUS, &status);
>> - if (ret < 0)
>> - return ret;
>> -
>> - return status;
>> -}
>> -
>> static int wait_for_fec_detected(struct drm_dp_aux *aux, bool enabled)
>> {
>> struct intel_display *display = to_intel_display(aux->drm_dev);
>> int mask = enabled ? DP_FEC_DECODE_EN_DETECTED :
>> DP_FEC_DECODE_DIS_DETECTED;
>> - int status;
>> - int err;
>> + u8 status = 0;
>> + int ret, err;
>>
>> - err = readx_poll_timeout(read_fec_detected_status, aux, status,
>> - status & mask || status < 0,
>> - 10000, 200000);
>> + ret = read_poll_timeout(drm_dp_dpcd_readb, err,
>
> drm_dp_dpcd_read_byte()? With that it looks ok:
Oh, yes.
>
> Reviewed-by: Imre Deak <imre.d...@intel.com>
>
>> + err || (status & mask),
>> + 10 * 1000, 200 * 1000, false,
>
> Nit: there's also USEC_PER_MSEC.
I considered that, and decided the straight 1000 is more obvious.
BR,
Jani.
>
>> + aux, DP_FEC_STATUS, &status);
>>
>> - if (err || status < 0) {
>> + /* Either can be non-zero, but not both */
>> + ret = ret ?: err;
>> + if (ret) {
>> drm_dbg_kms(display->drm,
>> - "Failed waiting for FEC %s to get detected: %d
>> (status %d)\n",
>> - str_enabled_disabled(enabled), err, status);
>> - return err ? err : status;
>> + "Failed waiting for FEC %s to get detected: %d
>> (status 0x%02x)\n",
>> + str_enabled_disabled(enabled), ret, status);
>> + return ret;
>> }
>>
>> return 0;
>> --
>> 2.39.5
>>
--
Jani Nikula, Intel
