Hi Sam, On Tue, Jun 25, 2019 at 11:24:19PM +0200, Sam Ravnborg wrote: > On Tue, Jun 25, 2019 at 07:05:19PM +0200, Guido Günther wrote: > > Allow to specify regulators for vcc and iovcc. According to the data > > sheet the panel wants vcc (2.8V) and iovcc (1.8V) and there's no startup > > dependency between the two. > s/jh057n0090/jh057n00900 > > > > > Signed-off-by: Guido Günther <agx@xxxxxxxxxxx> > > --- > > .../drm/panel/panel-rocktech-jh057n00900.c | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c b/drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c > > index b8a069055fbc..f8f6f087b9bc 100644 > > --- a/drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c > > +++ b/drivers/gpu/drm/panel/panel-rocktech-jh057n00900.c > > @@ -15,6 +15,7 @@ > > #include <linux/gpio/consumer.h> > > #include <linux/media-bus-format.h> > > #include <linux/module.h> > > +#include <linux/regulator/consumer.h> > > #include <video/display_timing.h> > > #include <video/mipi_display.h> > > > > @@ -47,6 +48,8 @@ struct jh057n { > > struct drm_panel panel; > > struct gpio_desc *reset_gpio; > > struct backlight_device *backlight; > > + struct regulator *vcc; > > + struct regulator *iovcc; > > bool prepared; > > > > struct dentry *debugfs; > > @@ -160,6 +163,8 @@ static int jh057n_unprepare(struct drm_panel *panel) > > return 0; > > > > mipi_dsi_dcs_set_display_off(dsi); > > + regulator_disable(ctx->iovcc); > > + regulator_disable(ctx->vcc); > > ctx->prepared = false; > > > > return 0; > > @@ -174,6 +179,13 @@ static int jh057n_prepare(struct drm_panel *panel) > > return 0; > > > > DRM_DEV_DEBUG_DRIVER(ctx->dev, "Resetting the panel\n"); > > + ret = regulator_enable(ctx->vcc); > > + if (ret < 0) > > + return ret; > > + ret = regulator_enable(ctx->iovcc); > > + if (ret < 0) > > + return ret; > > + > > gpiod_set_value_cansleep(ctx->reset_gpio, 1); > > usleep_range(20, 40); > > gpiod_set_value_cansleep(ctx->reset_gpio, 0); > > @@ -301,6 +313,13 @@ static int jh057n_probe(struct mipi_dsi_device *dsi) > > if (IS_ERR(ctx->backlight)) > > return PTR_ERR(ctx->backlight); > > > > + ctx->vcc = devm_regulator_get(dev, "vcc"); > > + if (IS_ERR(ctx->vcc)) > > + return PTR_ERR(ctx->vcc); > > + ctx->iovcc = devm_regulator_get(dev, "iovcc"); > > + if (IS_ERR(ctx->iovcc)) > > + return PTR_ERR(ctx->iovcc); > > + > Consider to write an error message. > The regulators are now mandatory, but they be missing in some device > trees. So it would be good to help them to understand why it fails. I've fixed this and your other comments in v2. > > With this considered: > Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx> Thanks! I've not added this yet since I made two more changes: - also print an error when regulator_enable() fails - disable vcc if enabling iovcc fails afterwards Hope this looks sane now. Cheers, -- Guido > > Sam >