| Message ID | 20220713081747.1729689-1-arun.r.murthy@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [PATCHv2] drm/i915/display: add support for dual panel backlight | expand |
On Wed, 13 Jul 2022, Arun R Murthy <arun.r.murthy@intel.com> wrote: > The patch with commit 20f85ef89d94 ("drm/i915/backlight: use unique > backlight device names") already adds support for dual panel backlight > but with error prints. Since the patch tried to create the backlight > device with the same name and upon failure will try with a different > name it leads to failure logs in dmesg inturn getting caught by CI. > > This patch alternately will check if the backlight class of same name > exists, will use a different name. > > v2: reworked on top of the patch 20f85ef89d94 ("drm/i915/backlight: use > unique backlight device names") > > Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com> > --- > .../gpu/drm/i915/display/intel_backlight.c | 24 ++++++++----------- > 1 file changed, 10 insertions(+), 14 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c > index 110fc98ec280..1e550d048e86 100644 > --- a/drivers/gpu/drm/i915/display/intel_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_backlight.c > @@ -971,26 +971,22 @@ int intel_backlight_device_register(struct intel_connector *connector) > if (!name) > return -ENOMEM; > > - bd = backlight_device_register(name, connector->base.kdev, connector, > - &intel_backlight_device_ops, &props); > - > - /* > - * Using the same name independent of the drm device or connector > - * prevents registration of multiple backlight devices in the > - * driver. However, we need to use the default name for backward > - * compatibility. Use unique names for subsequent backlight devices as a > - * fallback when the default name already exists. > - */ > - if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) { > + if (backlight_device_get_by_name(name)) { This leaks a reference count to the backlight device. It needs to be something like: bd = backlight_device_get_by_name(name); if (bd) { put_device(&bd->dev); /* ... */ } BR, Jani. > + /* > + * Using the same name independent of the drm device or connector > + * prevents registration of multiple backlight devices in the > + * driver. However, we need to use the default name for backward > + * compatibility. Use unique names for subsequent backlight devices as a > + * fallback when the default name already exists. > + */ > kfree(name); > name = kasprintf(GFP_KERNEL, "card%d-%s-backlight", > i915->drm.primary->index, connector->base.name); > if (!name) > return -ENOMEM; > - > - bd = backlight_device_register(name, connector->base.kdev, connector, > - &intel_backlight_device_ops, &props); > } > + bd = backlight_device_register(name, connector->base.kdev, connector, > + &intel_backlight_device_ops, &props); > > if (IS_ERR(bd)) { > drm_err(&i915->drm,
> -----Original Message----- > From: Nikula, Jani <jani.nikula@intel.com> > Sent: Tuesday, August 2, 2022 8:31 PM > To: Murthy, Arun R <arun.r.murthy@intel.com>; intel- > gfx@lists.freedesktop.org > Cc: Shankar, Uma <uma.shankar@intel.com>; Murthy, Arun R > <arun.r.murthy@intel.com> > Subject: Re: [PATCHv2] drm/i915/display: add support for dual panel > backlight > > On Wed, 13 Jul 2022, Arun R Murthy <arun.r.murthy@intel.com> wrote: > > The patch with commit 20f85ef89d94 ("drm/i915/backlight: use unique > > backlight device names") already adds support for dual panel backlight > > but with error prints. Since the patch tried to create the backlight > > device with the same name and upon failure will try with a different > > name it leads to failure logs in dmesg inturn getting caught by CI. > > > > This patch alternately will check if the backlight class of same name > > exists, will use a different name. > > > > v2: reworked on top of the patch 20f85ef89d94 ("drm/i915/backlight: > > use unique backlight device names") > > > > Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com> > > --- > > .../gpu/drm/i915/display/intel_backlight.c | 24 ++++++++----------- > > 1 file changed, 10 insertions(+), 14 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c > > b/drivers/gpu/drm/i915/display/intel_backlight.c > > index 110fc98ec280..1e550d048e86 100644 > > --- a/drivers/gpu/drm/i915/display/intel_backlight.c > > +++ b/drivers/gpu/drm/i915/display/intel_backlight.c > > @@ -971,26 +971,22 @@ int intel_backlight_device_register(struct > intel_connector *connector) > > if (!name) > > return -ENOMEM; > > > > - bd = backlight_device_register(name, connector->base.kdev, > connector, > > - &intel_backlight_device_ops, &props); > > - > > - /* > > - * Using the same name independent of the drm device or connector > > - * prevents registration of multiple backlight devices in the > > - * driver. However, we need to use the default name for backward > > - * compatibility. Use unique names for subsequent backlight devices > as a > > - * fallback when the default name already exists. > > - */ > > - if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) { > > + if (backlight_device_get_by_name(name)) { > > This leaks a reference count to the backlight device. It needs to be something > like: > > bd = backlight_device_get_by_name(name); > if (bd) { > put_device(&bd->dev); > > /* ... */ > } Thanks, Corrected and sent a revised version on patch! Thanks and Regards. Arun R Murthy --------------------
diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c index 110fc98ec280..1e550d048e86 100644 --- a/drivers/gpu/drm/i915/display/intel_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_backlight.c @@ -971,26 +971,22 @@ int intel_backlight_device_register(struct intel_connector *connector) if (!name) return -ENOMEM; - bd = backlight_device_register(name, connector->base.kdev, connector, - &intel_backlight_device_ops, &props); - - /* - * Using the same name independent of the drm device or connector - * prevents registration of multiple backlight devices in the - * driver. However, we need to use the default name for backward - * compatibility. Use unique names for subsequent backlight devices as a - * fallback when the default name already exists. - */ - if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) { + if (backlight_device_get_by_name(name)) { + /* + * Using the same name independent of the drm device or connector + * prevents registration of multiple backlight devices in the + * driver. However, we need to use the default name for backward + * compatibility. Use unique names for subsequent backlight devices as a + * fallback when the default name already exists. + */ kfree(name); name = kasprintf(GFP_KERNEL, "card%d-%s-backlight", i915->drm.primary->index, connector->base.name); if (!name) return -ENOMEM; - - bd = backlight_device_register(name, connector->base.kdev, connector, - &intel_backlight_device_ops, &props); } + bd = backlight_device_register(name, connector->base.kdev, connector, + &intel_backlight_device_ops, &props); if (IS_ERR(bd)) { drm_err(&i915->drm,
The patch with commit 20f85ef89d94 ("drm/i915/backlight: use unique backlight device names") already adds support for dual panel backlight but with error prints. Since the patch tried to create the backlight device with the same name and upon failure will try with a different name it leads to failure logs in dmesg inturn getting caught by CI. This patch alternately will check if the backlight class of same name exists, will use a different name. v2: reworked on top of the patch 20f85ef89d94 ("drm/i915/backlight: use unique backlight device names") Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com> --- .../gpu/drm/i915/display/intel_backlight.c | 24 ++++++++----------- 1 file changed, 10 insertions(+), 14 deletions(-)