On Wed, 2017-09-13 at 16:31 +0300, Ville Syrjälä wrote:
> On Tue, Sep 12, 2017 at 04:57:26PM -0700, Dhinakaran Pandiyan wrote:
> > There is just only one caller now, which already checks for
> > intel_dp->is_mst. So, remove this and fix some braces while at it.
>
> Hmm. So this depends on the subtle detail that
> drm_dp_mst_topology_mgr_resume() will "fail" if didn't enable mst
> prior to calling it. That fact isn't obvious at all, so I would
> suggest noting that in the commit message at least (maybe we should
> even have a comment in the code?)
>
> I'm assuming there are not other changes beyond just dropping the
> top level 'if (mst) { }' thing? This is one reason I prefer flat code.
> If the function had been flat to begin with the diff would have
> actually turned out legible. IIRC I even posted a flattening patch at
> some point but I guess it didn't go in. I would suggest that you take
> the opportunity to flatten out the rest of this function while you
> in the neighbourhood.
That was the goal :) Then I decided to simplify the function a little
bit in patches 4, 5, 6 and 7 before working on modifying it's structure.
>
> >
> > Signed-off-by: Dhinakaran Pandiyan <[email protected]>
> > ---
> > drivers/gpu/drm/i915/intel_dp.c | 85
> > ++++++++++++++++++++---------------------
> > 1 file changed, 42 insertions(+), 43 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c
> > b/drivers/gpu/drm/i915/intel_dp.c
> > index b3d95cb7546b..3f2ca10ccbcd 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4192,57 +4192,56 @@ static int
> > intel_dp_check_mst_status(struct intel_dp *intel_dp)
> > {
> > bool bret;
> > + u8 esi[DP_DPRX_ESI_LEN] = { 0 };
> > + int ret = 0;
> > + int retry;
> > + bool handled;
> >
> > - if (intel_dp->is_mst) {
> > - u8 esi[DP_DPRX_ESI_LEN] = { 0 };
> > - int ret = 0;
> > - int retry;
> > - bool handled;
> > - bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
> > + bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
> > go_again:
> > - if (bret == true) {
> > -
> > - /* check link status - esi[10] = 0x200c */
> > - if (intel_dp->active_mst_links &&
> > - !drm_dp_channel_eq_ok(&esi[10],
> > intel_dp->lane_count)) {
> > - DRM_DEBUG_KMS("channel EQ not ok,
> > retraining\n");
> > - intel_dp_start_link_train(intel_dp);
> > - intel_dp_stop_link_train(intel_dp);
> > - }
> > + if (bret == true) {
> > +
> > + /* check link status - esi[10] = 0x200c */
> > + if (intel_dp->active_mst_links &&
> > + !drm_dp_channel_eq_ok(&esi[10], intel_dp->lane_count)) {
> > + DRM_DEBUG_KMS("channel EQ not ok, retraining\n");
> > + intel_dp_start_link_train(intel_dp);
> > + intel_dp_stop_link_train(intel_dp);
> > + }
> >
> > - DRM_DEBUG_KMS("got esi %3ph\n", esi);
> > - ret = drm_dp_mst_hpd_irq(&intel_dp->mst_mgr, esi,
> > &handled);
> > -
> > - if (handled) {
> > - for (retry = 0; retry < 3; retry++) {
> > - int wret;
> > - wret = drm_dp_dpcd_write(&intel_dp->aux,
> > -
> > DP_SINK_COUNT_ESI+1,
> > - &esi[1], 3);
> > - if (wret == 3) {
> > - break;
> > - }
> > - }
> > + DRM_DEBUG_KMS("got esi %3ph\n", esi);
> > + ret = drm_dp_mst_hpd_irq(&intel_dp->mst_mgr, esi, &handled);
> >
> > - bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
> > - if (bret == true) {
> > - DRM_DEBUG_KMS("got esi2 %3ph\n", esi);
> > - goto go_again;
> > - }
> > - } else
> > - ret = 0;
> > + if (handled) {
> > + for (retry = 0; retry < 3; retry++) {
> > + int wret;
> >
> > - return ret;
> > + wret = drm_dp_dpcd_write(&intel_dp->aux,
> > + DP_SINK_COUNT_ESI+1,
> > + &esi[1], 3);
> > + if (wret == 3)
> > + break;
> > + }
> > +
> > + bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
> > + if (bret == true) {
> > + DRM_DEBUG_KMS("got esi2 %3ph\n", esi);
> > + goto go_again;
> > + }
> > } else {
> > - struct intel_digital_port *intel_dig_port =
> > dp_to_dig_port(intel_dp);
> > - DRM_DEBUG_KMS("failed to get ESI - device may have
> > failed\n");
> > - intel_dp->is_mst = false;
> > - drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
> > intel_dp->is_mst);
> > - /* send a hotplug event */
> > -
> > drm_kms_helper_hotplug_event(intel_dig_port->base.base.dev);
> > + ret = 0;
> > }
> > + } else {
> > + struct intel_digital_port *intel_dig_port =
> > dp_to_dig_port(intel_dp);
> > +
> > + DRM_DEBUG_KMS("failed to get ESI - device may have failed\n");
> > + intel_dp->is_mst = false;
> > + drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
> > + intel_dp->is_mst);
> > + drm_kms_helper_hotplug_event(intel_dig_port->base.base.dev);
> > + ret = -EINVAL;
> > }
> > - return -EINVAL;
> > + return ret;
> > }
> >
> > static void
> > --
> > 2.11.0
>
_______________________________________________
Intel-gfx mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
