As a preparation to adding HDMI CEC helper code, add CEC-related fields
to the struct drm_connector. Include both cec_adapter and cec_notifier,
allowing drivers to select which one to use. The unregister callback
is provided to let drivers unregister CEC-related data in a generic way
without polluting drm_connector.c with dependencies on the CEC
functions.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
drivers/gpu/drm/drm_connector.c | 13 ++++++++++++
include/drm/drm_connector.h | 44 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 57 insertions(+)
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 1383fa9fff9bcf31488453e209a36c6fe97be2f1..fffb718b09eaaac200e6abc7524bbfe98c4741f4 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -279,6 +279,7 @@ static int drm_connector_init_only(struct drm_device *dev,
INIT_LIST_HEAD(&connector->probed_modes);
INIT_LIST_HEAD(&connector->modes);
mutex_init(&connector->mutex);
+ mutex_init(&connector->cec.mutex);
mutex_init(&connector->eld_mutex);
mutex_init(&connector->edid_override_mutex);
mutex_init(&connector->hdmi.infoframes.lock);
@@ -698,6 +699,16 @@ static void drm_mode_remove(struct drm_connector *connector,
drm_mode_destroy(connector->dev, mode);
}
+static void drm_connector_cec_unregister(struct drm_connector *connector)
+{
+ mutex_lock(&connector->cec.mutex);
+
+ if (connector->cec.funcs->unregister)
+ connector->cec.funcs->unregister(connector);
+
+ mutex_unlock(&connector->cec.mutex);
+}
+
/**
* drm_connector_cleanup - cleans up an initialised connector
* @connector: connector to cleanup
@@ -718,6 +729,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
platform_device_unregister(connector->hdmi_audio.codec_pdev);
+ drm_connector_cec_unregister(connector);
+
if (connector->privacy_screen) {
drm_privacy_screen_put(connector->privacy_screen);
connector->privacy_screen = NULL;
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index f13d597370a30dc1b14c630ee00145256052ba56..6da840673b1209c84bbc396643c6033679a7ec74 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -46,6 +46,7 @@ struct drm_property_blob;
struct drm_printer;
struct drm_privacy_screen;
struct drm_edid;
+struct cec_adapter;
struct edid;
struct hdmi_codec_daifmt;
struct hdmi_codec_params;
@@ -1191,6 +1192,19 @@ struct drm_connector_hdmi_audio_funcs {
bool enable, int direction);
};
+/**
+ * struct drm_connector_cec_funcs - drm_hdmi_connector control functions
+ */
+struct drm_connector_cec_funcs {
+ /**
+ * @adap_unregister: unregister CEC adapter / notifier.
+ *
+ * The callback to unregister CEC adapter or notifier, so that the core
+ * DRM layer doesn't depend on the CEC_CORE.
+ */
+ void (*unregister)(struct drm_connector *connector);
+};
+
/**
* struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
*/
@@ -1832,6 +1846,31 @@ struct drm_connector_hdmi {
} infoframes;
};
+/**
+ * struct drm_connector_cec - DRM Connector CEC-related structure
+ */
+struct drm_connector_cec {
+ /**
+ * @mutex: protects all CEC-related fields
+ */
+ struct mutex mutex;
+
+ /**
+ * @adap: CEC adapter corresponding to the DRM connector.
+ */
+ struct cec_adapter *adapter;
+
+ /**
+ * @notifier: CEC notifier corresponding to the DRM connector.
+ */
+ struct cec_notifier *notifier;
+
+ /**
+ * @funcs: CEC Control Functions
+ */
+ const struct drm_connector_cec_funcs *funcs;
+};
+
/**
* struct drm_connector - central DRM connector control structure
*
@@ -2253,6 +2292,11 @@ struct drm_connector {
* @hdmi_audio: HDMI codec properties and non-DRM state.
*/
struct drm_connector_hdmi_audio hdmi_audio;
+
+ /**
+ * @cec: CEC-related data.
+ */
+ struct drm_connector_cec cec;
};
#define obj_to_connector(x) container_of(x, struct drm_connector, base)
--
2.39.5On Sun, Jan 26, 2025 at 03:29:06PM +0200, Dmitry Baryshkov wrote:
> As a preparation to adding HDMI CEC helper code, add CEC-related fields
> to the struct drm_connector. Include both cec_adapter and cec_notifier,
> allowing drivers to select which one to use. The unregister callback
> is provided to let drivers unregister CEC-related data in a generic way
> without polluting drm_connector.c with dependencies on the CEC
> functions.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
> drivers/gpu/drm/drm_connector.c | 13 ++++++++++++
> include/drm/drm_connector.h | 44 +++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 57 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 1383fa9fff9bcf31488453e209a36c6fe97be2f1..fffb718b09eaaac200e6abc7524bbfe98c4741f4 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -279,6 +279,7 @@ static int drm_connector_init_only(struct drm_device *dev,
> INIT_LIST_HEAD(&connector->probed_modes);
> INIT_LIST_HEAD(&connector->modes);
> mutex_init(&connector->mutex);
> + mutex_init(&connector->cec.mutex);
> mutex_init(&connector->eld_mutex);
> mutex_init(&connector->edid_override_mutex);
> mutex_init(&connector->hdmi.infoframes.lock);
> @@ -698,6 +699,16 @@ static void drm_mode_remove(struct drm_connector *connector,
> drm_mode_destroy(connector->dev, mode);
> }
>
> +static void drm_connector_cec_unregister(struct drm_connector *connector)
> +{
> + mutex_lock(&connector->cec.mutex);
> +
> + if (connector->cec.funcs->unregister)
> + connector->cec.funcs->unregister(connector);
> +
> + mutex_unlock(&connector->cec.mutex);
> +}
> +
> /**
> * drm_connector_cleanup - cleans up an initialised connector
> * @connector: connector to cleanup
> @@ -718,6 +729,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
>
> platform_device_unregister(connector->hdmi_audio.codec_pdev);
>
> + drm_connector_cec_unregister(connector);
> +
This should either be in a separate patch, or mentioned in the commit title/log
> if (connector->privacy_screen) {
> drm_privacy_screen_put(connector->privacy_screen);
> connector->privacy_screen = NULL;
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index f13d597370a30dc1b14c630ee00145256052ba56..6da840673b1209c84bbc396643c6033679a7ec74 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -46,6 +46,7 @@ struct drm_property_blob;
> struct drm_printer;
> struct drm_privacy_screen;
> struct drm_edid;
> +struct cec_adapter;
> struct edid;
> struct hdmi_codec_daifmt;
> struct hdmi_codec_params;
> @@ -1191,6 +1192,19 @@ struct drm_connector_hdmi_audio_funcs {
> bool enable, int direction);
> };
>
> +/**
> + * struct drm_connector_cec_funcs - drm_hdmi_connector control functions
> + */
> +struct drm_connector_cec_funcs {
> + /**
> + * @adap_unregister: unregister CEC adapter / notifier.
> + *
> + * The callback to unregister CEC adapter or notifier, so that the core
> + * DRM layer doesn't depend on the CEC_CORE.
> + */
> + void (*unregister)(struct drm_connector *connector);
> +};
> +
> /**
> * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
> */
> @@ -1832,6 +1846,31 @@ struct drm_connector_hdmi {
> } infoframes;
> };
>
> +/**
> + * struct drm_connector_cec - DRM Connector CEC-related structure
> + */
> +struct drm_connector_cec {
> + /**
> + * @mutex: protects all CEC-related fields
> + */
All fields? Which fields require to be protected by a specific mutex
here?
Maxime
On Tue, Jan 28, 2025 at 11:33:05AM +0100, Maxime Ripard wrote:
> On Sun, Jan 26, 2025 at 03:29:06PM +0200, Dmitry Baryshkov wrote:
> > As a preparation to adding HDMI CEC helper code, add CEC-related fields
> > to the struct drm_connector. Include both cec_adapter and cec_notifier,
> > allowing drivers to select which one to use. The unregister callback
> > is provided to let drivers unregister CEC-related data in a generic way
> > without polluting drm_connector.c with dependencies on the CEC
> > functions.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> > drivers/gpu/drm/drm_connector.c | 13 ++++++++++++
> > include/drm/drm_connector.h | 44 +++++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 57 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> > index 1383fa9fff9bcf31488453e209a36c6fe97be2f1..fffb718b09eaaac200e6abc7524bbfe98c4741f4 100644
> > --- a/drivers/gpu/drm/drm_connector.c
> > +++ b/drivers/gpu/drm/drm_connector.c
> > @@ -279,6 +279,7 @@ static int drm_connector_init_only(struct drm_device *dev,
> > INIT_LIST_HEAD(&connector->probed_modes);
> > INIT_LIST_HEAD(&connector->modes);
> > mutex_init(&connector->mutex);
> > + mutex_init(&connector->cec.mutex);
> > mutex_init(&connector->eld_mutex);
> > mutex_init(&connector->edid_override_mutex);
> > mutex_init(&connector->hdmi.infoframes.lock);
> > @@ -698,6 +699,16 @@ static void drm_mode_remove(struct drm_connector *connector,
> > drm_mode_destroy(connector->dev, mode);
> > }
> >
> > +static void drm_connector_cec_unregister(struct drm_connector *connector)
> > +{
> > + mutex_lock(&connector->cec.mutex);
> > +
> > + if (connector->cec.funcs->unregister)
> > + connector->cec.funcs->unregister(connector);
> > +
> > + mutex_unlock(&connector->cec.mutex);
> > +}
> > +
> > /**
> > * drm_connector_cleanup - cleans up an initialised connector
> > * @connector: connector to cleanup
> > @@ -718,6 +729,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
> >
> > platform_device_unregister(connector->hdmi_audio.codec_pdev);
> >
> > + drm_connector_cec_unregister(connector);
> > +
>
> This should either be in a separate patch, or mentioned in the commit title/log
I'll mention it in the commit message.
>
> > if (connector->privacy_screen) {
> > drm_privacy_screen_put(connector->privacy_screen);
> > connector->privacy_screen = NULL;
> > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > index f13d597370a30dc1b14c630ee00145256052ba56..6da840673b1209c84bbc396643c6033679a7ec74 100644
> > --- a/include/drm/drm_connector.h
> > +++ b/include/drm/drm_connector.h
> > @@ -46,6 +46,7 @@ struct drm_property_blob;
> > struct drm_printer;
> > struct drm_privacy_screen;
> > struct drm_edid;
> > +struct cec_adapter;
> > struct edid;
> > struct hdmi_codec_daifmt;
> > struct hdmi_codec_params;
> > @@ -1191,6 +1192,19 @@ struct drm_connector_hdmi_audio_funcs {
> > bool enable, int direction);
> > };
> >
> > +/**
> > + * struct drm_connector_cec_funcs - drm_hdmi_connector control functions
> > + */
> > +struct drm_connector_cec_funcs {
> > + /**
> > + * @adap_unregister: unregister CEC adapter / notifier.
> > + *
> > + * The callback to unregister CEC adapter or notifier, so that the core
> > + * DRM layer doesn't depend on the CEC_CORE.
> > + */
> > + void (*unregister)(struct drm_connector *connector);
> > +};
> > +
> > /**
> > * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
> > */
> > @@ -1832,6 +1846,31 @@ struct drm_connector_hdmi {
> > } infoframes;
> > };
> >
> > +/**
> > + * struct drm_connector_cec - DRM Connector CEC-related structure
> > + */
> > +struct drm_connector_cec {
> > + /**
> > + * @mutex: protects all CEC-related fields
> > + */
>
> All fields? Which fields require to be protected by a specific mutex
> here?
Yes, all the fields. adapter, notifier and funcs are all protected by
the mutex. See the drm_connector_cec_unregister() implementation (and
corresponding unregister() callbacks implementations.
--
With best wishes
Dmitry
On Tue, Jan 28, 2025 at 03:12:41PM +0200, Dmitry Baryshkov wrote:
> On Tue, Jan 28, 2025 at 11:33:05AM +0100, Maxime Ripard wrote:
> > On Sun, Jan 26, 2025 at 03:29:06PM +0200, Dmitry Baryshkov wrote:
> > > As a preparation to adding HDMI CEC helper code, add CEC-related fields
> > > to the struct drm_connector. Include both cec_adapter and cec_notifier,
> > > allowing drivers to select which one to use. The unregister callback
> > > is provided to let drivers unregister CEC-related data in a generic way
> > > without polluting drm_connector.c with dependencies on the CEC
> > > functions.
> > >
> > > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > > ---
> > > drivers/gpu/drm/drm_connector.c | 13 ++++++++++++
> > > include/drm/drm_connector.h | 44 +++++++++++++++++++++++++++++++++++++++++
> > > 2 files changed, 57 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> > > index 1383fa9fff9bcf31488453e209a36c6fe97be2f1..fffb718b09eaaac200e6abc7524bbfe98c4741f4 100644
> > > --- a/drivers/gpu/drm/drm_connector.c
> > > +++ b/drivers/gpu/drm/drm_connector.c
> > > @@ -279,6 +279,7 @@ static int drm_connector_init_only(struct drm_device *dev,
> > > INIT_LIST_HEAD(&connector->probed_modes);
> > > INIT_LIST_HEAD(&connector->modes);
> > > mutex_init(&connector->mutex);
> > > + mutex_init(&connector->cec.mutex);
> > > mutex_init(&connector->eld_mutex);
> > > mutex_init(&connector->edid_override_mutex);
> > > mutex_init(&connector->hdmi.infoframes.lock);
> > > @@ -698,6 +699,16 @@ static void drm_mode_remove(struct drm_connector *connector,
> > > drm_mode_destroy(connector->dev, mode);
> > > }
> > >
> > > +static void drm_connector_cec_unregister(struct drm_connector *connector)
> > > +{
> > > + mutex_lock(&connector->cec.mutex);
> > > +
> > > + if (connector->cec.funcs->unregister)
> > > + connector->cec.funcs->unregister(connector);
> > > +
> > > + mutex_unlock(&connector->cec.mutex);
> > > +}
> > > +
> > > /**
> > > * drm_connector_cleanup - cleans up an initialised connector
> > > * @connector: connector to cleanup
> > > @@ -718,6 +729,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
> > >
> > > platform_device_unregister(connector->hdmi_audio.codec_pdev);
> > >
> > > + drm_connector_cec_unregister(connector);
> > > +
> >
> > This should either be in a separate patch, or mentioned in the commit title/log
>
> I'll mention it in the commit message.
>
> >
> > > if (connector->privacy_screen) {
> > > drm_privacy_screen_put(connector->privacy_screen);
> > > connector->privacy_screen = NULL;
> > > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > > index f13d597370a30dc1b14c630ee00145256052ba56..6da840673b1209c84bbc396643c6033679a7ec74 100644
> > > --- a/include/drm/drm_connector.h
> > > +++ b/include/drm/drm_connector.h
> > > @@ -46,6 +46,7 @@ struct drm_property_blob;
> > > struct drm_printer;
> > > struct drm_privacy_screen;
> > > struct drm_edid;
> > > +struct cec_adapter;
> > > struct edid;
> > > struct hdmi_codec_daifmt;
> > > struct hdmi_codec_params;
> > > @@ -1191,6 +1192,19 @@ struct drm_connector_hdmi_audio_funcs {
> > > bool enable, int direction);
> > > };
> > >
> > > +/**
> > > + * struct drm_connector_cec_funcs - drm_hdmi_connector control functions
> > > + */
> > > +struct drm_connector_cec_funcs {
> > > + /**
> > > + * @adap_unregister: unregister CEC adapter / notifier.
> > > + *
> > > + * The callback to unregister CEC adapter or notifier, so that the core
> > > + * DRM layer doesn't depend on the CEC_CORE.
> > > + */
> > > + void (*unregister)(struct drm_connector *connector);
> > > +};
> > > +
> > > /**
> > > * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
> > > */
> > > @@ -1832,6 +1846,31 @@ struct drm_connector_hdmi {
> > > } infoframes;
> > > };
> > >
> > > +/**
> > > + * struct drm_connector_cec - DRM Connector CEC-related structure
> > > + */
> > > +struct drm_connector_cec {
> > > + /**
> > > + * @mutex: protects all CEC-related fields
> > > + */
> >
> > All fields? Which fields require to be protected by a specific mutex
> > here?
>
> Yes, all the fields. adapter, notifier and funcs are all protected by
> the mutex. See the drm_connector_cec_unregister() implementation (and
> corresponding unregister() callbacks implementations.
That's still surprising to me. Like, what concurrency source / code path
will need to make sure funcs is updated properly? or the adapter and
notifier?
Maxime
On Wed, 5 Feb 2025 at 16:28, Maxime Ripard <mripard@kernel.org> wrote:
>
> On Tue, Jan 28, 2025 at 03:12:41PM +0200, Dmitry Baryshkov wrote:
> > On Tue, Jan 28, 2025 at 11:33:05AM +0100, Maxime Ripard wrote:
> > > On Sun, Jan 26, 2025 at 03:29:06PM +0200, Dmitry Baryshkov wrote:
> > > > As a preparation to adding HDMI CEC helper code, add CEC-related fields
> > > > to the struct drm_connector. Include both cec_adapter and cec_notifier,
> > > > allowing drivers to select which one to use. The unregister callback
> > > > is provided to let drivers unregister CEC-related data in a generic way
> > > > without polluting drm_connector.c with dependencies on the CEC
> > > > functions.
> > > >
> > > > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > > > ---
> > > > drivers/gpu/drm/drm_connector.c | 13 ++++++++++++
> > > > include/drm/drm_connector.h | 44 +++++++++++++++++++++++++++++++++++++++++
> > > > 2 files changed, 57 insertions(+)
> > > >
> > > > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> > > > index 1383fa9fff9bcf31488453e209a36c6fe97be2f1..fffb718b09eaaac200e6abc7524bbfe98c4741f4 100644
> > > > --- a/drivers/gpu/drm/drm_connector.c
> > > > +++ b/drivers/gpu/drm/drm_connector.c
> > > > @@ -279,6 +279,7 @@ static int drm_connector_init_only(struct drm_device *dev,
> > > > INIT_LIST_HEAD(&connector->probed_modes);
> > > > INIT_LIST_HEAD(&connector->modes);
> > > > mutex_init(&connector->mutex);
> > > > + mutex_init(&connector->cec.mutex);
> > > > mutex_init(&connector->eld_mutex);
> > > > mutex_init(&connector->edid_override_mutex);
> > > > mutex_init(&connector->hdmi.infoframes.lock);
> > > > @@ -698,6 +699,16 @@ static void drm_mode_remove(struct drm_connector *connector,
> > > > drm_mode_destroy(connector->dev, mode);
> > > > }
> > > >
> > > > +static void drm_connector_cec_unregister(struct drm_connector *connector)
> > > > +{
> > > > + mutex_lock(&connector->cec.mutex);
> > > > +
> > > > + if (connector->cec.funcs->unregister)
> > > > + connector->cec.funcs->unregister(connector);
> > > > +
> > > > + mutex_unlock(&connector->cec.mutex);
> > > > +}
> > > > +
> > > > /**
> > > > * drm_connector_cleanup - cleans up an initialised connector
> > > > * @connector: connector to cleanup
> > > > @@ -718,6 +729,8 @@ void drm_connector_cleanup(struct drm_connector *connector)
> > > >
> > > > platform_device_unregister(connector->hdmi_audio.codec_pdev);
> > > >
> > > > + drm_connector_cec_unregister(connector);
> > > > +
> > >
> > > This should either be in a separate patch, or mentioned in the commit title/log
> >
> > I'll mention it in the commit message.
> >
> > >
> > > > if (connector->privacy_screen) {
> > > > drm_privacy_screen_put(connector->privacy_screen);
> > > > connector->privacy_screen = NULL;
> > > > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > > > index f13d597370a30dc1b14c630ee00145256052ba56..6da840673b1209c84bbc396643c6033679a7ec74 100644
> > > > --- a/include/drm/drm_connector.h
> > > > +++ b/include/drm/drm_connector.h
> > > > @@ -46,6 +46,7 @@ struct drm_property_blob;
> > > > struct drm_printer;
> > > > struct drm_privacy_screen;
> > > > struct drm_edid;
> > > > +struct cec_adapter;
> > > > struct edid;
> > > > struct hdmi_codec_daifmt;
> > > > struct hdmi_codec_params;
> > > > @@ -1191,6 +1192,19 @@ struct drm_connector_hdmi_audio_funcs {
> > > > bool enable, int direction);
> > > > };
> > > >
> > > > +/**
> > > > + * struct drm_connector_cec_funcs - drm_hdmi_connector control functions
> > > > + */
> > > > +struct drm_connector_cec_funcs {
> > > > + /**
> > > > + * @adap_unregister: unregister CEC adapter / notifier.
> > > > + *
> > > > + * The callback to unregister CEC adapter or notifier, so that the core
> > > > + * DRM layer doesn't depend on the CEC_CORE.
> > > > + */
> > > > + void (*unregister)(struct drm_connector *connector);
> > > > +};
> > > > +
> > > > /**
> > > > * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
> > > > */
> > > > @@ -1832,6 +1846,31 @@ struct drm_connector_hdmi {
> > > > } infoframes;
> > > > };
> > > >
> > > > +/**
> > > > + * struct drm_connector_cec - DRM Connector CEC-related structure
> > > > + */
> > > > +struct drm_connector_cec {
> > > > + /**
> > > > + * @mutex: protects all CEC-related fields
> > > > + */
> > >
> > > All fields? Which fields require to be protected by a specific mutex
> > > here?
> >
> > Yes, all the fields. adapter, notifier and funcs are all protected by
> > the mutex. See the drm_connector_cec_unregister() implementation (and
> > corresponding unregister() callbacks implementations.
>
> That's still surprising to me. Like, what concurrency source / code path
> will need to make sure funcs is updated properly? or the adapter and
> notifier?
I'll have to check, maybe we can lift that and really protect only the
adapter and the notifier. I was using ->funcs != NULL as a way to
check that CEC is registered at all (and thus unsetting it on CEC
unregistration). But maybe that's not that necessary.
>
> Maxime
--
With best wishes
Dmitry
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