linux-dev/drivers/media/cec/core, branch master

media: cec: add support for Absolute Volume Control

2022-09-24T06:50:04Z

Add support for this new CEC message. This was added in HDMI 2.1a. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: log when claiming LA fails unexpectedly

2022-06-20T09:30:30Z

If there is a hardware problem such as someone pulling the CEC line low continuously, then the POLL message will fail with an error other than OK, NACK, ABORTED or TIMEOUT. Log the tx_status value in that case to help debug this. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: drop activate_cnt, use state info instead

2022-05-13T09:29:39Z

Using an activation counter to decide when the enable or disable the cec adapter is not the best approach and can lead to race conditions. Change this to determining the current status of the adapter, and enable or disable the adapter accordingly. It now only needs to be called whenever there is a chance that the state changes, and it can handle enabling/disabling monitoring as well if needed. This simplifies the code and it should be a more robust approach as well. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: reconfigure if the PA changes during configuration

2022-05-13T09:29:16Z

If the physical address changes (i.e. becomes invalid, then valid again) while the adapter is still claiming free logical addresses, then trigger a reconfiguration since any claimed LAs may now be stale. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: fix is_configuring state

2022-05-13T09:28:54Z

If an adapter is trying to claim a free logical address then it is in the 'is_configuring' state. If during that process the cable is disconnected (HPD goes low, which in turn invalidates the physical address), then cec_adap_unconfigure() is called, and that set the is_configuring boolean to false, even though the thread that's trying to claim an LA is still running. Don't touch the is_configuring bool in cec_adap_unconfigure(), it will eventually be cleared by the thread. By making that change the cec_config_log_addr() function also had to change: it was aborting if is_configuring became false (since that is what cec_adap_unconfigure() did), but that no longer works. Instead check if the physical address is invalid. That is a much more appropriate check anyway. This fixes a bug where the the adapter could be disabled even though the device was still configuring. This could cause POLL transmits to time out. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: stop trying LAs on CEC_TX_STATUS_TIMEOUT

2022-05-13T09:28:35Z

If, while trying to claim a free logical address, a POLL message times out, then abort this process. A CEC_TX_STATUS_TIMEOUT should be handled the same as a CEC_TX_STATUS_ABORTED. This avoids a situation where transmits time out due to a driver or hardware bug and it takes ages before the attempt to find available free logical addresses finishes. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-adap.c: don't unconfigure if already unconfigured

2022-05-13T09:28:06Z

The __cec_s_log_addrs() function can configure or unconfigure the adapter. The ioctl handler in cec-api.c will prevent it from being called to configure the adapter if it was already configured (or in the process of configuring). But it can still be called to unconfigure an already unconfigured adapter, and it didn't check for that. This can cause cec_activate_cnt_dec() to be called too often, causing a WARN_ON. Instead first check if adap->log_addrs.num_log_addrs == 0 and return since in that case the adapter is already unconfigured. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-pin.c: don't zero work_pin_num_events in adap_enable

2022-05-13T09:27:47Z

It's OK to keep the pending pin events when disabling or enabling the 'adapter'. Zeroing this can cause a race condition if this happens when the pin kthread is handling a pin event and calls atomic_dec later, causing work_pin_num_events to become negative. Just leave pending events in the queue, they'll be read eventually. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec-pin.c: disabling the adapter cannot call kthread_stop

2022-05-13T09:27:19Z

When the adap_enable callback is called the adap->lock is held. When disabling the adapter it attempts to stop the kthread that deals with receiving and transmitting messages. However, kthread_stop waits for the thread to stop, so all that time adap->lock is held. Unfortunately, the kernel thread itself can call functions that take that same lock, so a deadlock can occur. Change the logic to keep the kernel thread running and instead when disabling the adapter, just set the pin to high, go to idle and then to state OFF and disable the interrupt. Only stop the kernel thread when the adapter is deleted. This way disabling the adapter will not wait for anything and the deadlock is avoided. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab

media: cec: add optional adap_configured callback

2022-04-24T06:41:35Z

This new optional callback is called when the adapter is fully configured or fully unconfigured. Some drivers may have to take action when this happens. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab