Message ID | 20171031193258.17373-1-eric@anholt.net (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Tue, 31 Oct 2017 12:32:57 -0700 Eric Anholt <eric@anholt.net> wrote: > It seems that trying to go from unlatched to unlatched will time out > waiting for STOP, and we can just skip that. > > Signed-off-by: Eric Anholt <eric@anholt.net> Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com> > --- > drivers/gpu/drm/vc4/vc4_dsi.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c > index 94085f8bcd68..8aa897835118 100644 > --- a/drivers/gpu/drm/vc4/vc4_dsi.c > +++ b/drivers/gpu/drm/vc4/vc4_dsi.c > @@ -753,6 +753,11 @@ static void vc4_dsi_ulps(struct vc4_dsi *dsi, bool ulps) > (dsi->lanes > 2 ? DSI1_STAT_PHY_D2_STOP : 0) | > (dsi->lanes > 3 ? DSI1_STAT_PHY_D3_STOP : 0)); > int ret; > + bool ulps_currently_enabled = (DSI_PORT_READ(PHY_AFEC0) & > + DSI_PORT_BIT(PHY_AFEC0_LATCH_ULPS)); > + > + if (ulps == ulps_currently_enabled) > + return; > > DSI_PORT_WRITE(STAT, stat_ulps); > DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) | phyc_ulps);
diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c index 94085f8bcd68..8aa897835118 100644 --- a/drivers/gpu/drm/vc4/vc4_dsi.c +++ b/drivers/gpu/drm/vc4/vc4_dsi.c @@ -753,6 +753,11 @@ static void vc4_dsi_ulps(struct vc4_dsi *dsi, bool ulps) (dsi->lanes > 2 ? DSI1_STAT_PHY_D2_STOP : 0) | (dsi->lanes > 3 ? DSI1_STAT_PHY_D3_STOP : 0)); int ret; + bool ulps_currently_enabled = (DSI_PORT_READ(PHY_AFEC0) & + DSI_PORT_BIT(PHY_AFEC0_LATCH_ULPS)); + + if (ulps == ulps_currently_enabled) + return; DSI_PORT_WRITE(STAT, stat_ulps); DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) | phyc_ulps);
It seems that trying to go from unlatched to unlatched will time out waiting for STOP, and we can just skip that. Signed-off-by: Eric Anholt <eric@anholt.net> --- drivers/gpu/drm/vc4/vc4_dsi.c | 5 +++++ 1 file changed, 5 insertions(+)