Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Thu, 2021-02-18 at 17:31 +0200, Ville Syrjälä wrote: > On Thu, Feb 18, 2021 at 10:35:05AM +0200, Jani Nikula wrote: > > On Fri, 12 Feb 2021, Lyude Paul wrote: > > > I think it wouldn't be a bad idea to just address this with a followup > > > series > > > instead and use the old DRM_DEBUG_* macros in the mean time. > > > > aux->dev is there, could also use dev_dbg et al. in the mean time. They > > handle NULL dev gracefully too if the driver didn't set that. > > Last I looked aux->dev was random. Some drivers point it at the > connector vs. some at the the pci/platform device. > That's correct-for most SoCs the AUX channel is actually a standalone platform device that isn't associated with the DRM device by default. /But/ I went through the tree yesterday and the day before and did a bunch of cleanup around DP aux registration, added a drm_dev field and hooked it up in every driver with an aux channel, and then converted all of the DP helpers (including dual mode and MST) over to using drm_dbg_*() variants. Once I've gotten through reading all my email for today I'm going to do a quick sanity check on it and then post the series to dri-devel. -- Sincerely, Lyude Paul (she/her) Software Engineer at Red Hat Note: I deal with a lot of emails and have a lot of bugs on my plate. If you've asked me a question, are waiting for a review/merge on a patch, etc. and I haven't responded in a while, please feel free to send me another email to check on my status. I don't bite! ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Thu, Feb 18, 2021 at 10:35:05AM +0200, Jani Nikula wrote: > On Fri, 12 Feb 2021, Lyude Paul wrote: > > I think it wouldn't be a bad idea to just address this with a followup > > series > > instead and use the old DRM_DEBUG_* macros in the mean time. > > aux->dev is there, could also use dev_dbg et al. in the mean time. They > handle NULL dev gracefully too if the driver didn't set that. Last I looked aux->dev was random. Some drivers point it at the connector vs. some at the the pci/platform device. -- Ville Syrjälä Intel ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Fri, 12 Feb 2021, Lyude Paul wrote: > I think it wouldn't be a bad idea to just address this with a followup series > instead and use the old DRM_DEBUG_* macros in the mean time. aux->dev is there, could also use dev_dbg et al. in the mean time. They handle NULL dev gracefully too if the driver didn't set that. BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Wed, 2021-02-10 at 23:15 -0500, Rodrigo Vivi wrote:
> On Mon, Feb 08, 2021 at 06:39:00PM -0500, Lyude Paul wrote:
> > Since we're about to implement eDP backlight support in nouveau using the
> > standard protocol from VESA, we might as well just take the code that's
> > already written for this and move it into a set of shared DRM helpers.
> >
> > Note that these helpers are intended to handle DPCD related backlight
> > control bits such as setting the brightness level over AUX, probing the
> > backlight's TCON, enabling/disabling the backlight over AUX if supported,
> > etc. Any PWM-related portions of backlight control are explicitly left up
> > to the driver, as these will vary from platform to platform.
> >
> > The only exception to this is the calculation of the PWM frequency
> > pre-divider value. This is because the only platform-specific information
> > required for this is the PWM frequency of the panel, which the driver is
> > expected to provide if available. The actual algorithm for calculating this
> > value is standard and is defined in the eDP specification from VESA.
> >
> > Note that these helpers do not yet implement the full range of features
> > the VESA backlight interface provides, and only provide the following
> > functionality (all of which was already present in i915's DPCD backlight
> > support):
> >
> > * Basic control of brightness levels
> > * Basic probing of backlight capabilities
> > * Helpers for enabling and disabling the backlight
> >
> > v3:
> > * Split out changes to i915's backlight code to separate patches to make it
> > easier to review
> > v4:
> > * Style/spelling changes from Thomas Zimmermann
> >
> > Signed-off-by: Lyude Paul
> > Cc: Jani Nikula
> > Cc: Dave Airlie
> > Cc: greg.depo...@gmail.com
> > ---
> > drivers/gpu/drm/drm_dp_helper.c | 332 ++
> > .../drm/i915/display/intel_display_types.h | 5 +-
> > .../drm/i915/display/intel_dp_aux_backlight.c | 285 ++-
> > include/drm/drm_dp_helper.h | 48 +++
> > 4 files changed, 412 insertions(+), 258 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_dp_helper.c
> > b/drivers/gpu/drm/drm_dp_helper.c
> > index eedbb48815b7..1a3d4679d720 100644
> > --- a/drivers/gpu/drm/drm_dp_helper.c
> > +++ b/drivers/gpu/drm/drm_dp_helper.c
> > @@ -3082,3 +3082,335 @@ int drm_dp_pcon_convert_rgb_to_ycbcr(struct
> > drm_dp_aux *aux, u8 color_spc)
> > return 0;
> > }
> > EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
> > +
> > +/**
> > + * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel
> > via AUX
> > + * @aux: The DP AUX channel to use
> > + * @bl: Backlight capability info from drm_edp_backlight_init()
> > + * @level: The brightness level to set
> > + *
> > + * Sets the brightness level of an eDP panel's backlight. Note that the
> > panel's backlight must
> > + * already have been enabled by the driver by calling
> > drm_edp_backlight_enable().
> > + *
> > + * Returns: %0 on success, negative error code on failure
> > + */
> > +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct
> > drm_edp_backlight_info *bl,
> > + u16 level)
> > +{
> > + int ret;
> > + u8 buf[2] = { 0 };
> > +
> > + if (bl->lsb_reg_used) {
> > + buf[0] = (level & 0xff00) >> 8;
> > + buf[1] = (level & 0x00ff);
> > + } else {
> > + buf[0] = level;
> > + }
> > +
> > + ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf,
> > sizeof(buf));
> > + if (ret != sizeof(buf)) {
> > + DRM_ERROR("%s: Failed to write aux backlight level: %d\n",
> > aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(drm_edp_backlight_set_level);
> > +
> > +static int
> > +drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct
> > drm_edp_backlight_info *bl,
> > + bool enable)
> > +{
> > + int ret;
> > + u8 buf;
> > +
> > + /* The panel uses something other then DPCD for enabling its
> > backlight */
> > + if (!bl->aux_enable)
> > + return 0;
> > +
> > + ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, );
> > + if (ret != 1) {
> > + DRM_ERROR("%s: Failed to read eDP display control register:
> > %d\n", aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > + if (enable)
> > + buf |= DP_EDP_BACKLIGHT_ENABLE;
> > + else
> > + buf &= ~DP_EDP_BACKLIGHT_ENABLE;
> > +
> > + ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf);
> > + if (ret != 1) {
> > + DRM_ERROR("%s: Failed to write eDP display control register:
> > %d\n", aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > +
> > +
Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Wed, 2021-02-10 at 23:15 -0500, Rodrigo Vivi wrote:
> On Mon, Feb 08, 2021 at 06:39:00PM -0500, Lyude Paul wrote:
> > Since we're about to implement eDP backlight support in nouveau using the
> > standard protocol from VESA, we might as well just take the code that's
> > already written for this and move it into a set of shared DRM helpers.
> >
> > Note that these helpers are intended to handle DPCD related backlight
> > control bits such as setting the brightness level over AUX, probing the
> > backlight's TCON, enabling/disabling the backlight over AUX if supported,
> > etc. Any PWM-related portions of backlight control are explicitly left up
> > to the driver, as these will vary from platform to platform.
> >
> > The only exception to this is the calculation of the PWM frequency
> > pre-divider value. This is because the only platform-specific information
> > required for this is the PWM frequency of the panel, which the driver is
> > expected to provide if available. The actual algorithm for calculating this
> > value is standard and is defined in the eDP specification from VESA.
> >
> > Note that these helpers do not yet implement the full range of features
> > the VESA backlight interface provides, and only provide the following
> > functionality (all of which was already present in i915's DPCD backlight
> > support):
> >
> > * Basic control of brightness levels
> > * Basic probing of backlight capabilities
> > * Helpers for enabling and disabling the backlight
> >
> > v3:
> > * Split out changes to i915's backlight code to separate patches to make it
> > easier to review
> > v4:
> > * Style/spelling changes from Thomas Zimmermann
> >
> > Signed-off-by: Lyude Paul
> > Cc: Jani Nikula
> > Cc: Dave Airlie
> > Cc: greg.depo...@gmail.com
> > ---
> > drivers/gpu/drm/drm_dp_helper.c | 332 ++
> > .../drm/i915/display/intel_display_types.h | 5 +-
> > .../drm/i915/display/intel_dp_aux_backlight.c | 285 ++-
> > include/drm/drm_dp_helper.h | 48 +++
> > 4 files changed, 412 insertions(+), 258 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_dp_helper.c
> > b/drivers/gpu/drm/drm_dp_helper.c
> > index eedbb48815b7..1a3d4679d720 100644
> > --- a/drivers/gpu/drm/drm_dp_helper.c
> > +++ b/drivers/gpu/drm/drm_dp_helper.c
> > @@ -3082,3 +3082,335 @@ int drm_dp_pcon_convert_rgb_to_ycbcr(struct
> > drm_dp_aux *aux, u8 color_spc)
> > return 0;
> > }
> > EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
> > +
> > +/**
> > + * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel
> > via AUX
> > + * @aux: The DP AUX channel to use
> > + * @bl: Backlight capability info from drm_edp_backlight_init()
> > + * @level: The brightness level to set
> > + *
> > + * Sets the brightness level of an eDP panel's backlight. Note that the
> > panel's backlight must
> > + * already have been enabled by the driver by calling
> > drm_edp_backlight_enable().
> > + *
> > + * Returns: %0 on success, negative error code on failure
> > + */
> > +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct
> > drm_edp_backlight_info *bl,
> > + u16 level)
> > +{
> > + int ret;
> > + u8 buf[2] = { 0 };
> > +
> > + if (bl->lsb_reg_used) {
> > + buf[0] = (level & 0xff00) >> 8;
> > + buf[1] = (level & 0x00ff);
> > + } else {
> > + buf[0] = level;
> > + }
> > +
> > + ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf,
> > sizeof(buf));
> > + if (ret != sizeof(buf)) {
> > + DRM_ERROR("%s: Failed to write aux backlight level: %d\n",
> > aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL(drm_edp_backlight_set_level);
> > +
> > +static int
> > +drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct
> > drm_edp_backlight_info *bl,
> > + bool enable)
> > +{
> > + int ret;
> > + u8 buf;
> > +
> > + /* The panel uses something other then DPCD for enabling its
> > backlight */
> > + if (!bl->aux_enable)
> > + return 0;
> > +
> > + ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, );
> > + if (ret != 1) {
> > + DRM_ERROR("%s: Failed to read eDP display control register:
> > %d\n", aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > + if (enable)
> > + buf |= DP_EDP_BACKLIGHT_ENABLE;
> > + else
> > + buf &= ~DP_EDP_BACKLIGHT_ENABLE;
> > +
> > + ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf);
> > + if (ret != 1) {
> > + DRM_ERROR("%s: Failed to write eDP display control register:
> > %d\n", aux->name, ret);
> > + return ret < 0 ? ret : -EIO;
> > + }
> > +
> > +
Re: [Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
On Mon, Feb 08, 2021 at 06:39:00PM -0500, Lyude Paul wrote:
> Since we're about to implement eDP backlight support in nouveau using the
> standard protocol from VESA, we might as well just take the code that's
> already written for this and move it into a set of shared DRM helpers.
>
> Note that these helpers are intended to handle DPCD related backlight
> control bits such as setting the brightness level over AUX, probing the
> backlight's TCON, enabling/disabling the backlight over AUX if supported,
> etc. Any PWM-related portions of backlight control are explicitly left up
> to the driver, as these will vary from platform to platform.
>
> The only exception to this is the calculation of the PWM frequency
> pre-divider value. This is because the only platform-specific information
> required for this is the PWM frequency of the panel, which the driver is
> expected to provide if available. The actual algorithm for calculating this
> value is standard and is defined in the eDP specification from VESA.
>
> Note that these helpers do not yet implement the full range of features
> the VESA backlight interface provides, and only provide the following
> functionality (all of which was already present in i915's DPCD backlight
> support):
>
> * Basic control of brightness levels
> * Basic probing of backlight capabilities
> * Helpers for enabling and disabling the backlight
>
> v3:
> * Split out changes to i915's backlight code to separate patches to make it
> easier to review
> v4:
> * Style/spelling changes from Thomas Zimmermann
>
> Signed-off-by: Lyude Paul
> Cc: Jani Nikula
> Cc: Dave Airlie
> Cc: greg.depo...@gmail.com
> ---
> drivers/gpu/drm/drm_dp_helper.c | 332 ++
> .../drm/i915/display/intel_display_types.h| 5 +-
> .../drm/i915/display/intel_dp_aux_backlight.c | 285 ++-
> include/drm/drm_dp_helper.h | 48 +++
> 4 files changed, 412 insertions(+), 258 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
> index eedbb48815b7..1a3d4679d720 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -3082,3 +3082,335 @@ int drm_dp_pcon_convert_rgb_to_ycbcr(struct
> drm_dp_aux *aux, u8 color_spc)
> return 0;
> }
> EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
> +
> +/**
> + * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel
> via AUX
> + * @aux: The DP AUX channel to use
> + * @bl: Backlight capability info from drm_edp_backlight_init()
> + * @level: The brightness level to set
> + *
> + * Sets the brightness level of an eDP panel's backlight. Note that the
> panel's backlight must
> + * already have been enabled by the driver by calling
> drm_edp_backlight_enable().
> + *
> + * Returns: %0 on success, negative error code on failure
> + */
> +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct
> drm_edp_backlight_info *bl,
> + u16 level)
> +{
> + int ret;
> + u8 buf[2] = { 0 };
> +
> + if (bl->lsb_reg_used) {
> + buf[0] = (level & 0xff00) >> 8;
> + buf[1] = (level & 0x00ff);
> + } else {
> + buf[0] = level;
> + }
> +
> + ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf,
> sizeof(buf));
> + if (ret != sizeof(buf)) {
> + DRM_ERROR("%s: Failed to write aux backlight level: %d\n",
> aux->name, ret);
> + return ret < 0 ? ret : -EIO;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_edp_backlight_set_level);
> +
> +static int
> +drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct
> drm_edp_backlight_info *bl,
> + bool enable)
> +{
> + int ret;
> + u8 buf;
> +
> + /* The panel uses something other then DPCD for enabling its backlight
> */
> + if (!bl->aux_enable)
> + return 0;
> +
> + ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, );
> + if (ret != 1) {
> + DRM_ERROR("%s: Failed to read eDP display control register:
> %d\n", aux->name, ret);
> + return ret < 0 ? ret : -EIO;
> + }
> + if (enable)
> + buf |= DP_EDP_BACKLIGHT_ENABLE;
> + else
> + buf &= ~DP_EDP_BACKLIGHT_ENABLE;
> +
> + ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf);
> + if (ret != 1) {
> + DRM_ERROR("%s: Failed to write eDP display control register:
> %d\n", aux->name, ret);
> + return ret < 0 ? ret : -EIO;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * drm_edp_backlight_enable() - Enable an eDP panel's backlight using DPCD
> + * @aux: The DP AUX channel to use
> + * @bl: Backlight capability info from drm_edp_backlight_init()
> + * @level: The initial backlight level to set via AUX, if there is one
> + *
> + * This function handles enabling DPCD backlight controls on a panel over
> DPCD,
[Intel-gfx] [RFC v4 10/11] drm/dp: Extract i915's eDP backlight code into DRM helpers
Since we're about to implement eDP backlight support in nouveau using the
standard protocol from VESA, we might as well just take the code that's
already written for this and move it into a set of shared DRM helpers.
Note that these helpers are intended to handle DPCD related backlight
control bits such as setting the brightness level over AUX, probing the
backlight's TCON, enabling/disabling the backlight over AUX if supported,
etc. Any PWM-related portions of backlight control are explicitly left up
to the driver, as these will vary from platform to platform.
The only exception to this is the calculation of the PWM frequency
pre-divider value. This is because the only platform-specific information
required for this is the PWM frequency of the panel, which the driver is
expected to provide if available. The actual algorithm for calculating this
value is standard and is defined in the eDP specification from VESA.
Note that these helpers do not yet implement the full range of features
the VESA backlight interface provides, and only provide the following
functionality (all of which was already present in i915's DPCD backlight
support):
* Basic control of brightness levels
* Basic probing of backlight capabilities
* Helpers for enabling and disabling the backlight
v3:
* Split out changes to i915's backlight code to separate patches to make it
easier to review
v4:
* Style/spelling changes from Thomas Zimmermann
Signed-off-by: Lyude Paul
Cc: Jani Nikula
Cc: Dave Airlie
Cc: greg.depo...@gmail.com
---
drivers/gpu/drm/drm_dp_helper.c | 332 ++
.../drm/i915/display/intel_display_types.h| 5 +-
.../drm/i915/display/intel_dp_aux_backlight.c | 285 ++-
include/drm/drm_dp_helper.h | 48 +++
4 files changed, 412 insertions(+), 258 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index eedbb48815b7..1a3d4679d720 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -3082,3 +3082,335 @@ int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux
*aux, u8 color_spc)
return 0;
}
EXPORT_SYMBOL(drm_dp_pcon_convert_rgb_to_ycbcr);
+
+/**
+ * drm_edp_backlight_set_level() - Set the backlight level of an eDP panel via
AUX
+ * @aux: The DP AUX channel to use
+ * @bl: Backlight capability info from drm_edp_backlight_init()
+ * @level: The brightness level to set
+ *
+ * Sets the brightness level of an eDP panel's backlight. Note that the
panel's backlight must
+ * already have been enabled by the driver by calling
drm_edp_backlight_enable().
+ *
+ * Returns: %0 on success, negative error code on failure
+ */
+int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct
drm_edp_backlight_info *bl,
+ u16 level)
+{
+ int ret;
+ u8 buf[2] = { 0 };
+
+ if (bl->lsb_reg_used) {
+ buf[0] = (level & 0xff00) >> 8;
+ buf[1] = (level & 0x00ff);
+ } else {
+ buf[0] = level;
+ }
+
+ ret = drm_dp_dpcd_write(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB, buf,
sizeof(buf));
+ if (ret != sizeof(buf)) {
+ DRM_ERROR("%s: Failed to write aux backlight level: %d\n",
aux->name, ret);
+ return ret < 0 ? ret : -EIO;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_edp_backlight_set_level);
+
+static int
+drm_edp_backlight_set_enable(struct drm_dp_aux *aux, const struct
drm_edp_backlight_info *bl,
+bool enable)
+{
+ int ret;
+ u8 buf;
+
+ /* The panel uses something other then DPCD for enabling its backlight
*/
+ if (!bl->aux_enable)
+ return 0;
+
+ ret = drm_dp_dpcd_readb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, );
+ if (ret != 1) {
+ DRM_ERROR("%s: Failed to read eDP display control register:
%d\n", aux->name, ret);
+ return ret < 0 ? ret : -EIO;
+ }
+ if (enable)
+ buf |= DP_EDP_BACKLIGHT_ENABLE;
+ else
+ buf &= ~DP_EDP_BACKLIGHT_ENABLE;
+
+ ret = drm_dp_dpcd_writeb(aux, DP_EDP_DISPLAY_CONTROL_REGISTER, buf);
+ if (ret != 1) {
+ DRM_ERROR("%s: Failed to write eDP display control register:
%d\n", aux->name, ret);
+ return ret < 0 ? ret : -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * drm_edp_backlight_enable() - Enable an eDP panel's backlight using DPCD
+ * @aux: The DP AUX channel to use
+ * @bl: Backlight capability info from drm_edp_backlight_init()
+ * @level: The initial backlight level to set via AUX, if there is one
+ *
+ * This function handles enabling DPCD backlight controls on a panel over
DPCD, while additionally
+ * restoring any important backlight state such as the given backlight level,
the brightness byte
+ * count, backlight frequency, etc.
+ *
+ * Note that certain panels, while supporting brightness level controls over
DPCD, may not
