linux-toradex.git/include/media/cec.h, branch v6.1

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

2022-05-13T09:29:39+00:00

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

2022-05-13T09:29:16+00:00

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: add optional adap_configured callback

2022-04-24T06:41:35+00:00

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

media: cec: add xfer_timeout_ms field

2022-04-24T06:41:06+00:00

Allow drivers to change the transmit timeout value, i.e. after how
long should a transmit be considered 'lost', i.e. the corresponding
cec_transmit_done_ts was never called.

Some CEC devices have their own timeout, and so this timeout value must be
longer than that hardware timeout value. If it is shorter then the
framework would consider the transmit lost, even though it is effectively
still in progress at the hardware level.

Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab

media: cec: abort if the current transmit was canceled

2022-04-24T06:38:19+00:00

If a transmit-in-progress was canceled, then, once the transmit
is done, mark it as aborted and refrain from retrying the transmit.

To signal this situation the new transmit_in_progress_aborted field is
set to true.

The old implementation would just set adap->transmitting to NULL and
set adap->transmit_in_progress to false, but on the hardware level
the transmit was still ongoing. However, the framework would think
the transmit was aborted, and if a new transmit was issued, then
it could overwrite the HW buffer containing the old transmit with the
new transmit, leading to garbled data on the CEC bus.

Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab

media: cec: call enable_adap on s_log_addrs

2022-04-24T06:37:58+00:00

Don't enable/disable the adapter if the first fh is opened or the
last fh is closed, instead do this when the adapter is configured
or unconfigured, and also when we enter Monitor All or Monitor Pin
mode for the first time or we exit the Monitor All/Pin mode for the
last time.

However, if needs_hpd is true, then do this when the physical
address is set or cleared: in that case the adapter typically is
powered by the HPD, so it really is disabled when the HPD is low.
This case (needs_hpd is true) was already handled in this way, so
this wasn't changed.

The problem with the old behavior was that if the HPD goes low when
no fh is open, and a transmit was in progress, then the adapter would
be disabled, typically stopping the transmit immediately which
leaves a partial message on the bus, which isn't nice and can confuse
some adapters.

It makes much more sense to disable it only when the adapter is
unconfigured and we're not monitoring the bus, since then you really
won't be using it anymore.

To keep track of this store a CEC activation count and call adap_enable
only when it goes from 0 to 1 or back to 0.

Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab

media: cec: fix a deadlock situation

2021-12-07T10:29:56+00:00

The cec_devnode struct has a lock meant to serialize access
to the fields of this struct. This lock is taken during
device node (un)registration and when opening or releasing a
filehandle to the device node. When the last open filehandle
is closed the cec adapter might be disabled by calling the
adap_enable driver callback with the devnode.lock held.

However, if during that callback a message or event arrives
then the driver will call one of the cec_queue_event()
variants in cec-adap.c, and those will take the same devnode.lock
to walk the open filehandle list.

This obviously causes a deadlock.

This is quite easy to reproduce with the cec-gpio driver since that
uses the cec-pin framework which generated lots of events and uses
a kernel thread for the processing, so when adap_enable is called
the thread is still running and can generate events.

But I suspect that it might also happen with other drivers if an
interrupt arrives signaling e.g. a received message before adap_enable
had a chance to disable the interrupts.

This patch adds a new mutex to serialize access to the fhs list.
When adap_enable() is called the devnode.lock mutex is held, but
not devnode.lock_fhs. The event functions in cec-adap.c will now
use devnode.lock_fhs instead of devnode.lock, ensuring that it is
safe to call those functions from the adap_enable callback.

This specific issue only happens if the last open filehandle is closed
and the physical address is invalid. This is not something that
happens during normal operation, but it does happen when monitoring
CEC traffic (e.g. cec-ctl --monitor) with an unconfigured CEC adapter.

Signed-off-by: Hans Verkuil 
Cc:   # for v5.13 and up
Signed-off-by: Mauro Carvalho Chehab

media: core headers: fix kernel-doc warnings

2021-03-22T09:22:22+00:00

This patch fixes the following kernel-doc warnings:

include/uapi/linux/videodev2.h:996: warning: Function parameter or member 'm' not described in 'v4l2_plane'
include/uapi/linux/videodev2.h:996: warning: Function parameter or member 'reserved' not described in 'v4l2_plane'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'm' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'reserved2' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'reserved' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1068: warning: Function parameter or member 'tv' not described in 'v4l2_timeval_to_ns'
include/uapi/linux/videodev2.h:1068: warning: Excess function parameter 'ts' description in 'v4l2_timeval_to_ns'
include/uapi/linux/videodev2.h:1138: warning: Function parameter or member 'reserved' not described in 'v4l2_exportbuffer'
include/uapi/linux/videodev2.h:2237: warning: Function parameter or member 'reserved' not described in 'v4l2_plane_pix_format'
include/uapi/linux/videodev2.h:2270: warning: Function parameter or member 'hsv_enc' not described in 'v4l2_pix_format_mplane'
include/uapi/linux/videodev2.h:2270: warning: Function parameter or member 'reserved' not described in 'v4l2_pix_format_mplane'
include/uapi/linux/videodev2.h:2281: warning: Function parameter or member 'reserved' not described in 'v4l2_sdr_format'
include/uapi/linux/videodev2.h:2315: warning: Function parameter or member 'fmt' not described in 'v4l2_format'

include/uapi/linux/v4l2-subdev.h:53: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_format'
include/uapi/linux/v4l2-subdev.h:66: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_crop'
include/uapi/linux/v4l2-subdev.h:89: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_mbus_code_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'min_width' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'max_width' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'min_height' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'max_height' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:119: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_interval'
include/uapi/linux/v4l2-subdev.h:140: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_interval_enum'

include/uapi/linux/cec.h:406: warning: Function parameter or member 'raw' not described in 'cec_connector_info'
include/uapi/linux/cec.h:470: warning: Function parameter or member 'flags' not described in 'cec_event'

include/media/v4l2-h264.h:82: warning: Function parameter or member 'reflist' not described in 'v4l2_h264_build_p_ref_list'
include/media/v4l2-h264.h:82: warning: expecting prototype for v4l2_h264_build_b_ref_lists(). Prototype was for v4l2_h264_build_p_ref_list()
instead

include/media/cec.h:50: warning: Function parameter or member 'lock' not described in 'cec_devnode'

include/media/v4l2-jpeg.h:122: warning: Function parameter or member 'num_dht' not described in 'v4l2_jpeg_header'
include/media/v4l2-jpeg.h:122: warning: Function parameter or member 'num_dqt' not described in 'v4l2_jpeg_header'

Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab

media: cec: no need to check return value of debugfs_create functions

2020-09-01T12:13:26+00:00

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab

media: cec: add adap_controls_phys_addr option

2020-07-04T10:15:26+00:00

Use of the cec notifier framework is required to support
CEC_CAP_CONNECTOR_INFO but some devices do not want physical address
updates from the notifier. This adds an option to allow registering
with a cec notifier without getting address updates.

[hans: document the new adap_controls_phys_addr bool]

Signed-off-by: Jeff Chase 
Signed-off-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab