Hi Alexander, Thank you for the patch. On Tue, Oct 19, 2021 at 08:52:39AM +0200, Alexander Stein wrote: > VCC needs to be enabled before releasing the enable GPIO. > > Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx> > Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/bridge/ti-sn65dsi83.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c > index 9072342566f3..c55c45d5d29a 100644 > --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c > +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c > @@ -33,6 +33,7 @@ > #include <linux/of_device.h> > #include <linux/of_graph.h> > #include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > > #include <drm/drm_atomic_helper.h> > #include <drm/drm_bridge.h> > @@ -143,6 +144,7 @@ struct sn65dsi83 { > struct mipi_dsi_device *dsi; > struct drm_bridge *panel_bridge; > struct gpio_desc *enable_gpio; > + struct regulator *vcc; > int dsi_lanes; > bool lvds_dual_link; > bool lvds_dual_link_even_odd_swap; > @@ -292,6 +294,11 @@ static void sn65dsi83_atomic_pre_enable(struct drm_bridge *bridge, > struct drm_bridge_state *old_bridge_state) > { > struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge); > + int ret; > + > + ret = regulator_enable(ctx->vcc); > + if (ret) > + dev_err(ctx->dev, "Failed to enable vcc: %i\n", ret); > > /* > * Reset the chip, pull EN line low for t_reset=10ms, > @@ -536,9 +543,14 @@ static void sn65dsi83_atomic_post_disable(struct drm_bridge *bridge, > struct drm_bridge_state *old_bridge_state) > { > struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge); > + int ret; > > /* Put the chip in reset, pull EN line low. */ > gpiod_set_value(ctx->enable_gpio, 0); > + > + ret = regulator_disable(ctx->vcc); > + if (ret) > + dev_err(ctx->dev, "Failed to disable vcc: %i\n", ret); > } > > static enum drm_mode_status > @@ -647,6 +659,12 @@ static int sn65dsi83_parse_dt(struct sn65dsi83 *ctx, enum sn65dsi83_model model) > > ctx->panel_bridge = panel_bridge; > > + ctx->vcc = devm_regulator_get(dev, "vcc"); > + if (IS_ERR(ctx->vcc)) > + return dev_err_probe(dev, PTR_ERR(ctx->vcc), > + "Failed to get supply 'vcc': %pe\n", > + ctx->vcc); > + > return 0; > } > -- Regards, Laurent Pinchart