by Sam McNally

[permalink] [raw]

Subject: Re: [PATCH 4/5] drm_dp_cec: add plumbing in preparation for MST support

On Tue, 8 Sep 2020 at 18:41, Hans Verkuil <[email protected]> wrote:
>
> On 01/09/2020 08:22, Sam McNally wrote:
> > From: Hans Verkuil <[email protected]>
> >
> > Signed-off-by: Hans Verkuil <[email protected]>
> > [[email protected]:
> > - rebased
> > - removed polling-related changes
> > - moved the calls to drm_dp_cec_(un)set_edid() into the next patch
> > ]
> > Signed-off-by: Sam McNally <[email protected]>
> > ---
> >
> > .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 2 +-
> > drivers/gpu/drm/drm_dp_cec.c | 22 ++++++++++---------
> > drivers/gpu/drm/i915/display/intel_dp.c | 2 +-
> > drivers/gpu/drm/nouveau/nouveau_connector.c | 2 +-
> > include/drm/drm_dp_helper.h | 6 +++--
> > 5 files changed, 19 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > index 461fa4da0a34..6e7075893ec9 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > @@ -419,7 +419,7 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm,
> >
> > drm_dp_aux_init(&aconnector->dm_dp_aux.aux);
> > drm_dp_cec_register_connector(&aconnector->dm_dp_aux.aux,
> > - &aconnector->base);
> > + &aconnector->base, false);
> >
> > if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
> > return;
> > diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> > index 3ab2609f9ec7..04ab7b88055c 100644
> > --- a/drivers/gpu/drm/drm_dp_cec.c
> > +++ b/drivers/gpu/drm/drm_dp_cec.c
> > @@ -14,6 +14,7 @@
> > #include <drm/drm_connector.h>
> > #include <drm/drm_device.h>
> > #include <drm/drm_dp_helper.h>
> > +#include <drm/drm_dp_mst_helper.h>
> >
> > /*
> > * Unfortunately it turns out that we have a chicken-and-egg situation
> > @@ -338,8 +339,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > if (aux->cec.adap) {
> > if (aux->cec.adap->capabilities == cec_caps &&
> > aux->cec.adap->available_log_addrs == num_las) {
> > - /* Unchanged, so just set the phys addr */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> > goto unlock;
> > }
> > /*
> > @@ -364,15 +363,16 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) {
> > cec_delete_adapter(aux->cec.adap);
> > aux->cec.adap = NULL;
> > - } else {
> > - /*
> > - * Update the phys addr for the new CEC adapter. When called
> > - * from drm_dp_cec_register_connector() edid == NULL, so in
> > - * that case the phys addr is just invalidated.
> > - */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> > }
> > unlock:
> > + /*
> > + * Update the phys addr for the new CEC adapter. When called
> > + * from drm_dp_cec_register_connector() edid == NULL, so in
> > + * that case the phys addr is just invalidated.
> > + */
>
> The comment is no longer in sync with the code: if EDID == NULL, then
> nothing is done due to the edid check in the 'if' below.
>
> > + if (aux->cec.adap && edid) {
>
> I think this should just be: if (aux->cec.adap)
>
> Also, the {} aren't necessary here.
>
> > + cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> > + }
> > mutex_unlock(&aux->cec.lock);
> > }
> > EXPORT_SYMBOL(drm_dp_cec_set_edid);
>
> Frankly, the changes to this function should be dropped completely, from
> what I can see they are not necessary. It was done in my original patch
> because of the way I handled mst, but you did it differently (and I think
> better), so these changes are no longer needed.
>
> I know I am actually commenting on my old patch, but that patch was from a
> work-in-progress git branch and was never meant as a 'proper' patch.
>
> However, what complicates matters is that after digging a bit more I discovered
> that commit 732300154980 ("drm: Do not call drm_dp_cec_set_edid() while registering
> DP connectors") changed drm_dp_cec_register_connector() so that it no longer
> calls drm_dp_cec_set_edid(), but the comments there and in this function were
> not updated. It would be nice if you can add a patch fixing these outdated
> comments.
>
> Regardless of that change in commit 732300154980, the edid pointer can still be
> NULL and the existing behavior should be kept (i.e. create a CEC device, but with
> an invalid physical address since there is no EDID for some reason).
>
> Regards,
>
> Hans
>

Thanks. Leaving drm_dp_cec_set_edid() unchanged combined with Lyude's
suggestion to use aux->is_remote removes the need for this patch
entirely.

> > @@ -418,6 +418,7 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> > * drm_dp_cec_register_connector() - register a new connector
> > * @aux: DisplayPort AUX channel
> > * @connector: drm connector
> > + * @is_mst: set to true if this is an MST branch
> > *
> > * A new connector was registered with associated CEC adapter name and
> > * CEC adapter parent device. After registering the name and parent
> > @@ -425,12 +426,13 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> > * CEC and to register a CEC adapter if that is the case.
> > */
> > void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > - struct drm_connector *connector)
> > + struct drm_connector *connector, bool is_mst)
> > {
> > WARN_ON(aux->cec.adap);
> > if (WARN_ON(!aux->transfer))
> > return;
> > aux->cec.connector = connector;
> > + aux->cec.is_mst = is_mst;
> > INIT_DELAYED_WORK(&aux->cec.unregister_work,
> > drm_dp_cec_unregister_work);
> > }
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 82b9de274f65..744cb55572f9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -6261,7 +6261,7 @@ intel_dp_connector_register(struct drm_connector *connector)
> > intel_dp->aux.dev = connector->kdev;
> > ret = drm_dp_aux_register(&intel_dp->aux);
> > if (!ret)
> > - drm_dp_cec_register_connector(&intel_dp->aux, connector);
> > + drm_dp_cec_register_connector(&intel_dp->aux, connector, false);
> > return ret;
> > }
> >
> > diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
> > index 49dd0cbc332f..671a70e95cd1 100644
> > --- a/drivers/gpu/drm/nouveau/nouveau_connector.c
> > +++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
> > @@ -1414,7 +1414,7 @@ nouveau_connector_create(struct drm_device *dev,
> > switch (type) {
> > case DRM_MODE_CONNECTOR_DisplayPort:
> > case DRM_MODE_CONNECTOR_eDP:
> > - drm_dp_cec_register_connector(&nv_connector->aux, connector);
> > + drm_dp_cec_register_connector(&nv_connector->aux, connector, false);
> > break;
> > }
> >
> > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
> > index 85513eeb2196..12bca1b9512b 100644
> > --- a/include/drm/drm_dp_helper.h
> > +++ b/include/drm/drm_dp_helper.h
> > @@ -1495,12 +1495,14 @@ struct drm_connector;
> > * @lock: mutex protecting this struct
> > * @adap: the CEC adapter for CEC-Tunneling-over-AUX support.
> > * @connector: the connector this CEC adapter is associated with
> > + * @is_mst: this is an MST branch
> > * @unregister_work: unregister the CEC adapter
> > */
> > struct drm_dp_aux_cec {
> > struct mutex lock;
> > struct cec_adapter *adap;
> > struct drm_connector *connector;
> > + bool is_mst;
> > struct delayed_work unregister_work;
> > };
> >
> > @@ -1746,7 +1748,7 @@ drm_dp_has_quirk(const struct drm_dp_desc *desc, u32 edid_quirks,
> > #ifdef CONFIG_DRM_DP_CEC
> > void drm_dp_cec_irq(struct drm_dp_aux *aux);
> > void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > - struct drm_connector *connector);
> > + struct drm_connector *connector, bool is_mst);
> > void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux);
> > void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid);
> > void drm_dp_cec_unset_edid(struct drm_dp_aux *aux);
> > @@ -1757,7 +1759,7 @@ static inline void drm_dp_cec_irq(struct drm_dp_aux *aux)
> >
> > static inline void
> > drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > - struct drm_connector *connector)
> > + struct drm_connector *connector, bool is_mst)
> > {
> > }
> >
> >
>

2020-09-09 07:11:58

by Sam McNally

[permalink] [raw]

Subject: Re: [PATCH 5/5] drm_dp_cec: add the implementation of MST support

On Tue, 8 Sep 2020 at 18:08, Hans Verkuil <[email protected]> wrote:
>
> Hi Sam,
>
> On 01/09/2020 08:22, Sam McNally wrote:
> > With DP v2.0 errata E5, CEC tunneling can be supported through an MST
> > topology.
>
> Oh wow, this is finally supported in the spec. Very nice to see this.
> Also very nice to see that my old experimental patches attempting to
> support CEC on MST didn't go to waste!
>
> Do you know of any MST HW that supports this? I'd love to experiment
> with this.

A Realtek RTD2142 with the right firmware can support CEC over MST.
There's nothing released with it that I know of though.
>
> Regards,
>
> Hans
>
> >
> > There are some minor differences for CEC tunneling through an MST
> > topology compared to CEC tunneling to an SST port:
> > - CEC IRQs are delivered via a sink event notify message
> > - CEC-related DPCD registers are accessed via remote DPCD reads and
> > writes.
> >
> > This results in the MST implementation diverging from the existing SST
> > implementation:
> > - sink event notify messages with CEC_IRQ ID set indicate CEC IRQ rather
> > than ESI1
> > - setting edid and handling CEC IRQs, which can be triggered from
> > contexts where locks held preclude HPD handling, are deferred to avoid
> > remote DPCD access which would block until HPD handling is performed
> > or a timeout
> >
> > Register and unregister for all MST connectors, ensuring their
> > drm_dp_aux_cec struct won't be accessed uninitialized.
> >
> > Signed-off-by: Sam McNally <[email protected]>
> > ---
> >
> > drivers/gpu/drm/drm_dp_cec.c | 67 +++++++++++++++++++++++++--
> > drivers/gpu/drm/drm_dp_mst_topology.c | 24 ++++++++++
> > include/drm/drm_dp_helper.h | 4 ++
> > 3 files changed, 90 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> > index 04ab7b88055c..9f6aeaa27f00 100644
> > --- a/drivers/gpu/drm/drm_dp_cec.c
> > +++ b/drivers/gpu/drm/drm_dp_cec.c
> > @@ -249,6 +249,10 @@ void drm_dp_cec_irq(struct drm_dp_aux *aux)
> > if (!aux->transfer)
> > return;
> >
> > + if (aux->cec.is_mst) {
> > + schedule_work(&aux->cec.mst_irq_work);
> > + return;
> > + }
> > mutex_lock(&aux->cec.lock);
> > if (!aux->cec.adap)
> > goto unlock;
> > @@ -277,6 +281,24 @@ static bool drm_dp_cec_cap(struct drm_dp_aux *aux, u8 *cec_cap)
> > return true;
> > }
> >
> > +static void drm_dp_cec_mst_irq_work(struct work_struct *work)
> > +{
> > + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux,
> > + cec.mst_irq_work);
> > + struct drm_dp_mst_port *port =
> > + container_of(aux, struct drm_dp_mst_port, aux);
> > +
> > + port = drm_dp_mst_topology_get_port_validated(port->mgr, port);
> > + if (!port)
> > + return;
> > + mutex_lock(&aux->cec.lock);
> > + if (aux->cec.adap)
> > + drm_dp_cec_handle_irq(aux);
> > +
> > + mutex_unlock(&aux->cec.lock);
> > + drm_dp_mst_topology_put_port(port);
> > +}
> > +
> > /*
> > * Called if the HPD was low for more than drm_dp_cec_unregister_delay
> > * seconds. This unregisters the CEC adapter.
> > @@ -298,7 +320,8 @@ static void drm_dp_cec_unregister_work(struct work_struct *work)
> > * were unchanged and just update the CEC physical address. Otherwise
> > * unregister the old CEC adapter and create a new one.
> > */
> > -void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > +static void drm_dp_cec_handle_set_edid(struct drm_dp_aux *aux,
> > + const struct edid *edid)
> > {
> > struct drm_connector *connector = aux->cec.connector;
> > u32 cec_caps = CEC_CAP_DEFAULTS | CEC_CAP_NEEDS_HPD |
> > @@ -307,10 +330,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > unsigned int num_las = 1;
> > u8 cap;
> >
> > - /* No transfer function was set, so not a DP connector */
> > - if (!aux->transfer)
> > - return;
> > -
> > #ifndef CONFIG_MEDIA_CEC_RC
> > /*
> > * CEC_CAP_RC is part of CEC_CAP_DEFAULTS, but it is stripped by
> > @@ -321,6 +340,7 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > */
> > cec_caps &= ~CEC_CAP_RC;
> > #endif
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > cancel_delayed_work_sync(&aux->cec.unregister_work);
> >
> > mutex_lock(&aux->cec.lock);
> > @@ -375,6 +395,18 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > }
> > mutex_unlock(&aux->cec.lock);
> > }
> > +
> > +void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > +{
> > + /* No transfer function was set, so not a DP connector */
> > + if (!aux->transfer)
> > + return;
> > +
> > + if (aux->cec.is_mst)
> > + schedule_work(&aux->cec.mst_set_edid_work);
> > + else
> > + drm_dp_cec_handle_set_edid(aux, edid);
> > +}
> > EXPORT_SYMBOL(drm_dp_cec_set_edid);
> >
> > /*
> > @@ -393,6 +425,8 @@ void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
> > goto unlock;
> >
> > cec_phys_addr_invalidate(aux->cec.adap);
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > +
> > /*
> > * We're done if we want to keep the CEC device
> > * (drm_dp_cec_unregister_delay is >= NEVER_UNREG_DELAY) or if the
> > @@ -414,6 +448,25 @@ void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
> > }
> > EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> >
> > +static void drm_dp_cec_mst_set_edid_work(struct work_struct *work)
> > +{
> > + struct drm_dp_aux *aux =
> > + container_of(work, struct drm_dp_aux, cec.mst_set_edid_work);
> > + struct drm_dp_mst_port *port =
> > + container_of(aux, struct drm_dp_mst_port, aux);
> > + struct edid *edid = NULL;
> > +
> > + port = drm_dp_mst_topology_get_port_validated(port->mgr, port);
> > + if (!port)
> > + return;
> > +
> > + edid = drm_get_edid(port->connector, &port->aux.ddc);
> > +
> > + drm_dp_cec_handle_set_edid(aux, edid);
> > +
> > + drm_dp_mst_topology_put_port(port);
> > +}
> > +
> > /**
> > * drm_dp_cec_register_connector() - register a new connector
> > * @aux: DisplayPort AUX channel
> > @@ -435,6 +488,8 @@ void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > aux->cec.is_mst = is_mst;
> > INIT_DELAYED_WORK(&aux->cec.unregister_work,
> > drm_dp_cec_unregister_work);
> > + INIT_WORK(&aux->cec.mst_irq_work, drm_dp_cec_mst_irq_work);
> > + INIT_WORK(&aux->cec.mst_set_edid_work, drm_dp_cec_mst_set_edid_work);
> > }
> > EXPORT_SYMBOL(drm_dp_cec_register_connector);
> >
> > @@ -444,6 +499,8 @@ EXPORT_SYMBOL(drm_dp_cec_register_connector);
> > */
> > void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux)
> > {
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > + cancel_work_sync(&aux->cec.mst_set_edid_work);
> > if (!aux->cec.adap)
> > return;
> > cancel_delayed_work_sync(&aux->cec.unregister_work);
> > diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> > index c783a2a1c114..fd9430d88fd6 100644
> > --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> > +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> > @@ -2183,6 +2183,8 @@ static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
> > int drm_dp_mst_connector_late_register(struct drm_connector *connector,
> > struct drm_dp_mst_port *port)
> > {
> > + drm_dp_cec_register_connector(&port->aux, connector, true);
> > +
> > DRM_DEBUG_KMS("registering %s remote bus for %s\n",
> > port->aux.name, connector->kdev->kobj.name);
> >
> > @@ -2206,6 +2208,8 @@ void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
> > DRM_DEBUG_KMS("unregistering %s remote bus for %s\n",
> > port->aux.name, connector->kdev->kobj.name);
> > drm_dp_aux_unregister_devnode(&port->aux);
> > +
> > + drm_dp_cec_unregister_connector(&port->aux);
> > }
> > EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister);
> >
> > @@ -2515,6 +2519,21 @@ drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb,
> > queue_work(system_long_wq, &mstb->mgr->work);
> > }
> >
> > +static void
> > +drm_dp_mst_handle_sink_event(struct drm_dp_mst_branch *mstb,
> > + struct drm_dp_sink_event_notify *sink_event)
> > +{
> > + struct drm_dp_mst_port *port;
> > +
> > + if (sink_event->event_id & DP_SINK_EVENT_CEC_IRQ_EVENT) {
> > + port = drm_dp_get_port(mstb, sink_event->port_number);
> > + if (port) {
> > + drm_dp_cec_irq(&port->aux);
> > + drm_dp_mst_topology_put_port(port);
> > + }
> > + }
> > +}
> > +
> > static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
> > u8 lct, u8 *rad)
> > {
> > @@ -3954,6 +3973,8 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
> > if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
> > drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
> > hotplug = true;
> > + } else if (msg->req_type == DP_SINK_EVENT_NOTIFY) {
> > + drm_dp_mst_handle_sink_event(mstb, &msg->u.sink_event);
> > }
> >
> > drm_dp_mst_topology_put_mstb(mstb);
> > @@ -4147,6 +4168,8 @@ drm_dp_mst_detect_port(struct drm_connector *connector,
> > break;
> > }
> > out:
> > + if (ret != connector_status_connected)
> > + drm_dp_cec_unset_edid(&port->aux);
> > drm_dp_mst_topology_put_port(port);
> > return ret;
> > }
> > @@ -4177,6 +4200,7 @@ struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_
> > edid = drm_get_edid(connector, &port->aux.ddc);
> > }
> > port->has_audio = drm_detect_monitor_audio(edid);
> > + drm_dp_cec_set_edid(&port->aux, edid);
> > drm_dp_mst_topology_put_port(port);
> > return edid;
> > }
> > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
> > index 12bca1b9512b..e973eba06875 100644
> > --- a/include/drm/drm_dp_helper.h
> > +++ b/include/drm/drm_dp_helper.h
> > @@ -1497,6 +1497,8 @@ struct drm_connector;
> > * @connector: the connector this CEC adapter is associated with
> > * @is_mst: this is an MST branch
> > * @unregister_work: unregister the CEC adapter
> > + * @mst_irq_work: IRQ for CEC events on an MST branch
> > + * @mst_set_edid_work: set the EDID for an MST branch
> > */
> > struct drm_dp_aux_cec {
> > struct mutex lock;
> > @@ -1504,6 +1506,8 @@ struct drm_dp_aux_cec {
> > struct drm_connector *connector;
> > bool is_mst;
> > struct delayed_work unregister_work;
> > + struct work_struct mst_irq_work;
> > + struct work_struct mst_set_edid_work;
> > };
> >
> > /**
> >
>

On Tue, 8 Sep 2020 at 18:08, Hans Verkuil <[email protected]> wrote:
>
> Hi Sam,
>
> On 01/09/2020 08:22, Sam McNally wrote:
> > With DP v2.0 errata E5, CEC tunneling can be supported through an MST
> > topology.
>
> Oh wow, this is finally supported in the spec. Very nice to see this.
> Also very nice to see that my old experimental patches attempting to
> support CEC on MST didn't go to waste!
>
> Do you know of any MST HW that supports this? I'd love to experiment
> with this.
>

> Regards,
>
> Hans
>
> >
> > There are some minor differences for CEC tunneling through an MST
> > topology compared to CEC tunneling to an SST port:
> > - CEC IRQs are delivered via a sink event notify message
> > - CEC-related DPCD registers are accessed via remote DPCD reads and
> > writes.
> >
> > This results in the MST implementation diverging from the existing SST
> > implementation:
> > - sink event notify messages with CEC_IRQ ID set indicate CEC IRQ rather
> > than ESI1
> > - setting edid and handling CEC IRQs, which can be triggered from
> > contexts where locks held preclude HPD handling, are deferred to avoid
> > remote DPCD access which would block until HPD handling is performed
> > or a timeout
> >
> > Register and unregister for all MST connectors, ensuring their
> > drm_dp_aux_cec struct won't be accessed uninitialized.
> >
> > Signed-off-by: Sam McNally <[email protected]>
> > ---
> >
> > drivers/gpu/drm/drm_dp_cec.c | 67 +++++++++++++++++++++++++--
> > drivers/gpu/drm/drm_dp_mst_topology.c | 24 ++++++++++
> > include/drm/drm_dp_helper.h | 4 ++
> > 3 files changed, 90 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> > index 04ab7b88055c..9f6aeaa27f00 100644
> > --- a/drivers/gpu/drm/drm_dp_cec.c
> > +++ b/drivers/gpu/drm/drm_dp_cec.c
> > @@ -249,6 +249,10 @@ void drm_dp_cec_irq(struct drm_dp_aux *aux)
> > if (!aux->transfer)
> > return;
> >
> > + if (aux->cec.is_mst) {
> > + schedule_work(&aux->cec.mst_irq_work);
> > + return;
> > + }
> > mutex_lock(&aux->cec.lock);
> > if (!aux->cec.adap)
> > goto unlock;
> > @@ -277,6 +281,24 @@ static bool drm_dp_cec_cap(struct drm_dp_aux *aux, u8 *cec_cap)
> > return true;
> > }
> >
> > +static void drm_dp_cec_mst_irq_work(struct work_struct *work)
> > +{
> > + struct drm_dp_aux *aux = container_of(work, struct drm_dp_aux,
> > + cec.mst_irq_work);
> > + struct drm_dp_mst_port *port =
> > + container_of(aux, struct drm_dp_mst_port, aux);
> > +
> > + port = drm_dp_mst_topology_get_port_validated(port->mgr, port);
> > + if (!port)
> > + return;
> > + mutex_lock(&aux->cec.lock);
> > + if (aux->cec.adap)
> > + drm_dp_cec_handle_irq(aux);
> > +
> > + mutex_unlock(&aux->cec.lock);
> > + drm_dp_mst_topology_put_port(port);
> > +}
> > +
> > /*
> > * Called if the HPD was low for more than drm_dp_cec_unregister_delay
> > * seconds. This unregisters the CEC adapter.
> > @@ -298,7 +320,8 @@ static void drm_dp_cec_unregister_work(struct work_struct *work)
> > * were unchanged and just update the CEC physical address. Otherwise
> > * unregister the old CEC adapter and create a new one.
> > */
> > -void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > +static void drm_dp_cec_handle_set_edid(struct drm_dp_aux *aux,
> > + const struct edid *edid)
> > {
> > struct drm_connector *connector = aux->cec.connector;
> > u32 cec_caps = CEC_CAP_DEFAULTS | CEC_CAP_NEEDS_HPD |
> > @@ -307,10 +330,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > unsigned int num_las = 1;
> > u8 cap;
> >
> > - /* No transfer function was set, so not a DP connector */
> > - if (!aux->transfer)
> > - return;
> > -
> > #ifndef CONFIG_MEDIA_CEC_RC
> > /*
> > * CEC_CAP_RC is part of CEC_CAP_DEFAULTS, but it is stripped by
> > @@ -321,6 +340,7 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > */
> > cec_caps &= ~CEC_CAP_RC;
> > #endif
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > cancel_delayed_work_sync(&aux->cec.unregister_work);
> >
> > mutex_lock(&aux->cec.lock);
> > @@ -375,6 +395,18 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > }
> > mutex_unlock(&aux->cec.lock);
> > }
> > +
> > +void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const struct edid *edid)
> > +{
> > + /* No transfer function was set, so not a DP connector */
> > + if (!aux->transfer)
> > + return;
> > +
> > + if (aux->cec.is_mst)
> > + schedule_work(&aux->cec.mst_set_edid_work);
> > + else
> > + drm_dp_cec_handle_set_edid(aux, edid);
> > +}
> > EXPORT_SYMBOL(drm_dp_cec_set_edid);
> >
> > /*
> > @@ -393,6 +425,8 @@ void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
> > goto unlock;
> >
> > cec_phys_addr_invalidate(aux->cec.adap);
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > +
> > /*
> > * We're done if we want to keep the CEC device
> > * (drm_dp_cec_unregister_delay is >= NEVER_UNREG_DELAY) or if the
> > @@ -414,6 +448,25 @@ void drm_dp_cec_unset_edid(struct drm_dp_aux *aux)
> > }
> > EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> >
> > +static void drm_dp_cec_mst_set_edid_work(struct work_struct *work)
> > +{
> > + struct drm_dp_aux *aux =
> > + container_of(work, struct drm_dp_aux, cec.mst_set_edid_work);
> > + struct drm_dp_mst_port *port =
> > + container_of(aux, struct drm_dp_mst_port, aux);
> > + struct edid *edid = NULL;
> > +
> > + port = drm_dp_mst_topology_get_port_validated(port->mgr, port);
> > + if (!port)
> > + return;
> > +
> > + edid = drm_get_edid(port->connector, &port->aux.ddc);
> > +
> > + drm_dp_cec_handle_set_edid(aux, edid);
> > +
> > + drm_dp_mst_topology_put_port(port);
> > +}
> > +
> > /**
> > * drm_dp_cec_register_connector() - register a new connector
> > * @aux: DisplayPort AUX channel
> > @@ -435,6 +488,8 @@ void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > aux->cec.is_mst = is_mst;
> > INIT_DELAYED_WORK(&aux->cec.unregister_work,
> > drm_dp_cec_unregister_work);
> > + INIT_WORK(&aux->cec.mst_irq_work, drm_dp_cec_mst_irq_work);
> > + INIT_WORK(&aux->cec.mst_set_edid_work, drm_dp_cec_mst_set_edid_work);
> > }
> > EXPORT_SYMBOL(drm_dp_cec_register_connector);
> >
> > @@ -444,6 +499,8 @@ EXPORT_SYMBOL(drm_dp_cec_register_connector);
> > */
> > void drm_dp_cec_unregister_connector(struct drm_dp_aux *aux)
> > {
> > + cancel_work_sync(&aux->cec.mst_irq_work);
> > + cancel_work_sync(&aux->cec.mst_set_edid_work);
> > if (!aux->cec.adap)
> > return;
> > cancel_delayed_work_sync(&aux->cec.unregister_work);
> > diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> > index c783a2a1c114..fd9430d88fd6 100644
> > --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> > +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> > @@ -2183,6 +2183,8 @@ static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb,
> > int drm_dp_mst_connector_late_register(struct drm_connector *connector,
> > struct drm_dp_mst_port *port)
> > {
> > + drm_dp_cec_register_connector(&port->aux, connector, true);
> > +
> > DRM_DEBUG_KMS("registering %s remote bus for %s\n",
> > port->aux.name, connector->kdev->kobj.name);
> >
> > @@ -2206,6 +2208,8 @@ void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
> > DRM_DEBUG_KMS("unregistering %s remote bus for %s\n",
> > port->aux.name, connector->kdev->kobj.name);
> > drm_dp_aux_unregister_devnode(&port->aux);
> > +
> > + drm_dp_cec_unregister_connector(&port->aux);
> > }
> > EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister);
> >
> > @@ -2515,6 +2519,21 @@ drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb,
> > queue_work(system_long_wq, &mstb->mgr->work);
> > }
> >
> > +static void
> > +drm_dp_mst_handle_sink_event(struct drm_dp_mst_branch *mstb,
> > + struct drm_dp_sink_event_notify *sink_event)
> > +{
> > + struct drm_dp_mst_port *port;
> > +
> > + if (sink_event->event_id & DP_SINK_EVENT_CEC_IRQ_EVENT) {
> > + port = drm_dp_get_port(mstb, sink_event->port_number);
> > + if (port) {
> > + drm_dp_cec_irq(&port->aux);
> > + drm_dp_mst_topology_put_port(port);
> > + }
> > + }
> > +}
> > +
> > static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr,
> > u8 lct, u8 *rad)
> > {
> > @@ -3954,6 +3973,8 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
> > if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
> > drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
> > hotplug = true;
> > + } else if (msg->req_type == DP_SINK_EVENT_NOTIFY) {
> > + drm_dp_mst_handle_sink_event(mstb, &msg->u.sink_event);
> > }
> >
> > drm_dp_mst_topology_put_mstb(mstb);
> > @@ -4147,6 +4168,8 @@ drm_dp_mst_detect_port(struct drm_connector *connector,
> > break;
> > }
> > out:
> > + if (ret != connector_status_connected)
> > + drm_dp_cec_unset_edid(&port->aux);
> > drm_dp_mst_topology_put_port(port);
> > return ret;
> > }
> > @@ -4177,6 +4200,7 @@ struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_
> > edid = drm_get_edid(connector, &port->aux.ddc);
> > }
> > port->has_audio = drm_detect_monitor_audio(edid);
> > + drm_dp_cec_set_edid(&port->aux, edid);
> > drm_dp_mst_topology_put_port(port);
> > return edid;
> > }
> > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
> > index 12bca1b9512b..e973eba06875 100644
> > --- a/include/drm/drm_dp_helper.h
> > +++ b/include/drm/drm_dp_helper.h
> > @@ -1497,6 +1497,8 @@ struct drm_connector;
> > * @connector: the connector this CEC adapter is associated with
> > * @is_mst: this is an MST branch
> > * @unregister_work: unregister the CEC adapter
> > + * @mst_irq_work: IRQ for CEC events on an MST branch
> > + * @mst_set_edid_work: set the EDID for an MST branch
> > */
> > struct drm_dp_aux_cec {
> > struct mutex lock;
> > @@ -1504,6 +1506,8 @@ struct drm_dp_aux_cec {
> > struct drm_connector *connector;
> > bool is_mst;
> > struct delayed_work unregister_work;
> > + struct work_struct mst_irq_work;
> > + struct work_struct mst_set_edid_work;
> > };
> >
> > /**
> >
>