Hi, On 3/25/21 12:48 PM, Hans de Goede wrote: > After the recently added commit fe0f1e3bfdfe ("drm/i915: Shut down > displays gracefully on reboot"), the DSI panel on a Cherry Trail based > Predia Basic tablet would no longer properly light up after reboot. > > I've managed to reproduce this without rebooting by doing: > chvt 3; echo 1 > /sys/class/graphics/fb0/blank;\ > echo 0 > /sys/class/graphics/fb0/blank > > Which rapidly turns the panel off and back on again. > > The vlv_dsi.c code uses an intel_dsi_msleep() helper for the various delays > used for panel on/off, since starting with MIPI-sequences version >= 3 the > delays are already included inside the MIPI-sequences. > > The problems exposed by the "Shut down displays gracefully on reboot" > change, show that using this helper for the panel_pwr_cycle_delay is > not the right thing to do. This has not been noticed until now because > normally the panel never is cycled off and directly on again in quick > succession. > > Change the msleep for the panel_pwr_cycle_delay to a normal msleep() > call to avoid the panel staying black after a quick off + on cycle. > > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Fixes: fe0f1e3bfdfe ("drm/i915: Shut down displays gracefully on reboot") > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> Ping? Ville AFAICT this is ready for merging, can you review this please so that I can push it to drm-intel-next ? Regards, Hans > --- > drivers/gpu/drm/i915/display/vlv_dsi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c > index d5a3f69c5df3..38d5a1f3ded5 100644 > --- a/drivers/gpu/drm/i915/display/vlv_dsi.c > +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c > @@ -996,14 +996,14 @@ static void intel_dsi_post_disable(struct intel_atomic_state *state, > * FIXME As we do with eDP, just make a note of the time here > * and perform the wait before the next panel power on. > */ > - intel_dsi_msleep(intel_dsi, intel_dsi->panel_pwr_cycle_delay); > + msleep(intel_dsi->panel_pwr_cycle_delay); > } > > static void intel_dsi_shutdown(struct intel_encoder *encoder) > { > struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder); > > - intel_dsi_msleep(intel_dsi, intel_dsi->panel_pwr_cycle_delay); > + msleep(intel_dsi->panel_pwr_cycle_delay); > } > > static bool intel_dsi_get_hw_state(struct intel_encoder *encoder, > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel