Commit Graph

51 Commits

Author SHA1 Message Date
Hans Verkuil a9e6107616 media: cec: fix a deadlock situation
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 <hverkuil-cisco@xs4all.nl>
Cc: <stable@vger.kernel.org>  # for v5.13 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-12-07 11:29:56 +01:00
Hans Verkuil f12b81e47f media: core headers: fix kernel-doc warnings
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 <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 10:22:22 +01:00
Greg Kroah-Hartman 5d0d7b9009 media: cec: no need to check return value of debugfs_create functions
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 <gregkh@linuxfoundation.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-01 14:13:26 +02:00
Jeff Chase 98f803cfa7 media: cec: add adap_controls_phys_addr option
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 <jnchase@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-07-04 12:15:26 +02:00
Hans Verkuil e233f81cfc media: media/cec.h: document cec_adapter fields
Document this core CEC structure.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-23 15:11:44 +02:00
Hans Verkuil 8dd65ed67e media: cec: remove unused waitq and phys_addrs fields
The cec_adapter struct contained a waitq field that isn't used
anywhere, so drop this.

It also contained a phys_addrs array to store any reported physical
addresses. However, this was never actually used, so this field is
removed as well. The original idea was to let the core keep track of
this information, but nothing was ever done with this. Should this
be needed in the future then it is easy enough to resurrect this.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-23 15:11:25 +02:00
Hans Verkuil e611164793 media: cec: remove unused functions
Remove several functions that are no longer used now that the
conversion of cec drivers to cec_notifier_conn_(un)register() and
cec_notifier_cec_adap_(un)register() is complete.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-01-08 14:38:06 +01:00
Dariusz Marcinkiewicz 9098c1c251 media: cec: expose the new connector info API
Until now the connector info API was a kernel-internal API only.
This moves it to the public API and adds the new ioctl to retrieve
this information.

Signed-off-by: Dariusz Marcinkiewicz <darekm@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-10-01 17:19:41 -03:00
Dariusz Marcinkiewicz 32a847f9fa media: cec: add struct cec_connector_info support
Define struct cec_connector_info in media/cec.h and define
CEC_CAP_CONNECTOR_INFO. In a later patch this will be moved to
uapi/linux/cec.h.

The CEC_CAP_CONNECTOR_INFO capability can be set by drivers, but
cec_allocate_adapter() will remove it again until the public API
for this can be enabled once all drm drivers wire this up correctly.

Also add the cec_fill_conn_info_from_drm and cec_s_conn_info functions,
which are needed by drm drivers to fill in the cec_connector info
based on a drm_connector.

The cec_notifier_(un)register and cec_register_cec_notifier
prototypes were moved from cec-notifier.h to cec.h since cec.h no longer
includes cec-notifier.h. These headers included each other before,
which caused various problems.

Due to these changes the seco-cec driver was changed as well: it
should include cec-notifier.h, not cec.h.

Signed-off-by: Dariusz Marcinkiewicz <darekm@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-06-27 07:18:43 -04:00
Hans Verkuil 32804fcb61 media: cec: keep track of outstanding transmits
I noticed that repeatedly running 'cec-ctl --playback' would occasionally
select 'Playback Device 2' instead of 'Playback Device 1', even though there
were no other Playback devices in the HDMI topology. This happened both with
'real' hardware and with the vivid CEC emulation, suggesting that this was an
issue in the core code that claims a logical address.

What 'cec-ctl --playback' does is to first clear all existing logical addresses,
and immediately after that configure the new desired device type.

The core code will poll the logical addresses trying to find a free address.
When found it will issue a few standard messages as per the CEC spec and return.
Those messages are queued up and will be transmitted asynchronously.

What happens is that if you run two 'cec-ctl --playback' commands in quick
succession, there is still a message of the first cec-ctl command being transmitted
when you reconfigure the adapter again in the second cec-ctl command.

When the logical addresses are cleared, then all information about outstanding
transmits inside the CEC core is also cleared, and the core is no longer aware
that there is still a transmit in flight.

When the hardware finishes the transmit it calls transmit_done and the CEC core
thinks it is actually in response of a POLL messages that is trying to find a
free logical address. The result of all this is that the core thinks that the
logical address for Playback Device 1 is in use, when it is really an earlier
transmit that ended.

The main transmit thread looks at adap->transmitting to check if a transmit
is in progress, but that is set to NULL when the adapter is unconfigured.
adap->transmitting represents the view of userspace, not that of the hardware.
So when unconfiguring the adapter the message is marked aborted from the point
of view of userspace, but seen from the PoV of the hardware it is still ongoing.

So introduce a new bool transmit_in_progress that represents the hardware state
and use that instead of adap->transmitting. Now the CEC core waits until the
hardware finishes the transmit before starting a new transmit.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: <stable@vger.kernel.org>      # for v4.18 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-11-23 05:56:14 -05:00
Sean Young 557c97b513 media: cec: name for RC passthrough device does not need 'RC for'
An RC device is does not need to be called 'RC for'. Simply the name
will suffice.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-10-05 11:28:13 -04:00
Hans Verkuil 7d867a1b76 media: cec: fix the Signal Free Time calculation
The calculation of the Signal Free Time in the framework was not
correct. If a message was received, then the next transmit should be
considered a New Initiator and use a shorter SFT value.

This was not done with the result that if both sides where continually
sending messages, they both could use the same SFT value and one side
could deny the other side access to the bus.

Note that this fix does not take the corner case into account where
a receive is in progress when you call adap_transmit.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.18 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-10-05 11:27:15 -04:00
Hans Verkuil 9cfd2753f8 media: cec/v4l2: move V4L2 specific CEC functions to V4L2
Several CEC functions are actually specific for use with receivers,
i.e. they should be part of the V4L2 subsystem, not CEC.

These functions deal with validating and modifying EDIDs for (HDMI)
receivers, and they do not actually have anything to do with the CEC
subsystem and whether or not CEC is enabled. The problem was that if
the CEC_CORE config option was not set, then these functions would
become stubs, but that's not right: they should always be valid.

So replace the cec_ prefix by v4l2_ and move them to v4l2-dv-timings.c.
Update all drivers that call these accordingly.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: <stable@vger.kernel.org>      # for v4.17 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-09-24 09:11:04 -04:00
Hans Verkuil b915bf575d media: cec: make cec_get_edid_spa_location() an inline function
This function is needed by both V4L2 and CEC, so move this to
cec.h as a static inline since there are no obvious shared
modules between the two subsystems.

This patch, together with the following ones, fixes a
dependency bug: if CEC_CORE is disabled, then building adv7604
(and other HDMI receivers) will fail because an essential
function is now stubbed out.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.17 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-09-24 09:09:07 -04:00
Hans Verkuil 4786b0d6f3 media: cec: add support for 5V signal testing
Add support for the new 5V CEC events

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-07-25 07:11:48 -04:00
Hans Verkuil 6ec1cbf6b1 media: cec: improve CEC pin event handling
It turns out that the struct cec_fh event buffer size of 64 events
(64 for CEC_EVENT_PIN_CEC_LOW and 64 for _HIGH) is too small. It's
about 160 ms worth of events and if the Raspberry Pi is busy, then it
might take too long for the application to be scheduled so that it can
drain the pending events. Increase these buffers to 800 events which
is at least 2 seconds worth of events.

There is also a FIFO in between the interrupt and the cec-pin thread.
The thread passes the events on to the CEC core. It is important that
should this FIFO fill up the cec core will be informed that events
have been lost so this can be communicated to the user by setting
CEC_EVENT_FL_DROPPED_EVENTS.

It is very hard to debug CEC problems if events were lost without
informing the user of that fact.

If events were dropped due to the FIFO filling up, then the debugfs
status file will let you know how many events were dropped.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-03-22 08:16:52 -04:00
Hans Verkuil 9ca400c18f media: cec: add core error injection support
Add two new ops (error_inj_show and error_inj_parse_line) to support
error injection functionality for CEC adapters. If both are present,
then the core will add a new error-inj debugfs file that can be used
to see the current error injection commands and to set error injection
commands.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-03-22 07:59:31 -04:00
Hans Verkuil ab15d248cc media: include/(uapi/)media: add SPDX license info
Replace the old license information with the corresponding SPDX
license for those headers that I authored.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2018-02-14 13:23:51 -05:00
Sean Young 57c642cb45 media: cec: move cec autorepeat handling to rc-core
CEC autorepeat is different than other protocols. Autorepeat is triggered
by the first repeated user control pressed CEC message, rather than a
fixed REP_DELAY.

This change also does away with the KEY_UP event directly after the first
KEY_DOWN event, which was used to stop autorepeat from starting.

See commit a9a249a2c9 ("media: cec: fix remote control passthrough")
for the original change.

Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-14 10:35:30 -05:00
Hans Verkuil c8959a39fd media: cec: disable the hardware when unregistered
When the device is being unregistered disable the hardware, don't wait
until cec_delete_adapter is called as the hardware may have disappeared by
then. This would be the case for hotplugable devices.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reported-by: Bård Eirik Winther <bwinther@cisco.com>
Tested-by: Bård Eirik Winther <bwinther@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-08 11:11:25 -05:00
Hans Verkuil 48ea2e926b media: cec: add the adap_monitor_pin_enable op
Some devices can monitor the CEC pin using an interrupt, but you
only want to enable the interrupt if you actually switch to pin
monitoring mode.

So add a new op that is called when pin monitoring needs to be
switched on or off.

Also fix a small bug where the initial CEC pin event was sent
again when calling S_MODE twice with the same CEC_MODE_MONITOR_PIN
mode.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-12-08 11:10:00 -05:00
Hans Verkuil 9267d90c56 media: cec.h: initialize *parent and *port in cec_phys_addr_validate
Make sure these values are set to avoid 'uninitialized variable'
warnings. Hasn't happened yet, but better safe than sorry.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-09-23 14:59:44 -04:00
Hans Verkuil 333ef6bd10 media: cec: add CEC_EVENT_PIN_HPD_LOW/HIGH events
Add support for two new low-level events: PIN_HPD_LOW and PIN_HPD_HIGH.

This is specifically meant for use with the upcoming cec-gpio driver
and makes it possible to trace when the HPD pin changes. Some HDMI
sinks do strange things with the HPD and this makes it easy to debug
this.

Note that this also moves the initialization of a devnode mutex and
list to the allocate_adapter function: if the HPD is high, then as
soon as the HPD interrupt is created an interrupt occurs and
cec_queue_pin_hpd_event() is called which requires that the devnode
mutex and list are initialized.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-09-23 07:43:04 -04:00
Hans Verkuil 28e11b15b6 media: cec: replace pin->cur_value by adap->cec_pin_is_high
The current CEC pin value (0 or 1) was part of the cec_pin struct,
but that assumes that CEC pin monitoring can only be used with
a driver that uses the low-level CEC pin framework.

But hardware that has both a high-level API and can monitor the
CEC pin at low-level at the same time does not need to depend on
the cec pin framework.

To support such devices remove the cur_value field from struct cec_pin
and add a cec_pin_is_high field to cec_adapter. This also makes it
possible to drop the '#ifdef CONFIG_CEC_PIN' in cec-api.c.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-08-26 08:35:10 -04:00
Hans Verkuil a9a249a2c9 media: cec: fix remote control passthrough
The 'Press and Hold' operation was not correctly implemented, in
particular the requirement that the repeat doesn't start until
the second identical keypress arrives. The REP_DELAY value also
had to be adjusted (see the comment in the code) to achieve the
desired behavior.

The 'enabled_protocols' field was also never set, fix that too. Since
CEC is a fixed protocol the driver has to set this field.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-08-20 09:59:34 -04:00
Sean Young 518f4b26be media: rc-core: rename input_name to device_name
When an ir-spi is registered, you get this message.

rc rc0: Unspecified device as /devices/platform/soc/3f215080.spi/spi_master/spi32766/spi32766.128/rc/rc0

"Unspecified device" refers to input_name, which makes no sense for IR
TX only devices. So, rename to device_name.

Also make driver_name const char* so that no casts are needed anywhere.

Now ir-spi reports:

rc rc0: IR SPI as /devices/platform/soc/3f215080.spi/spi_master/spi32766/spi32766.128/rc/rc0

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-08-20 09:43:52 -04:00
Hans Verkuil 9a6b2a8740 media: cec: rename pin events/function
The CEC_EVENT_PIN_LOW/HIGH defines and the cec_queue_pin_event() function
did not specify that these were about CEC pin events.

Since in the future there will also be HPD pin events it is wise to rename
the event defines and function to CEC_EVENT_PIN_CEC_LOW/HIGH and
cec_queue_pin_cec_event() now before these become part of the ABI.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-08-20 08:14:03 -04:00
Hans Verkuil ee0c503eac media: media/cec.h: add CEC_CAP_DEFAULTS
The CEC_CAP_LOG_ADDRS, CEC_CAP_TRANSMIT, CEC_CAP_PASSTHROUGH and
CEC_CAP_RC capabilities are normally always present.

Add a CEC_CAP_DEFAULTS define that ORs these four caps to simplify
drivers.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-08-09 09:36:54 -04:00
Hans Verkuil 5150418593 media: cec: move cec_register_cec_notifier to cec-notifier.h
The cec_register_cec_notifier function was in media/cec.h, but it
has to be in cec-notifier.h.

While we are at it, also document it and add a stub function for when
the notifier is disabled or the CEC core code is unreachable.

Based on an earlier patch from Jose Abreu <Jose.Abreu@synopsys.com>.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 13:00:01 -03:00
Hans Verkuil ea5c8ef296 media: cec-pin: add low-level pin hardware support
Add support for CEC hardware that relies on low-level pin polling or
GPIO interrupts.

One example is the Allwinner SoC. But any GPIO-based CEC implementation can
use this as well.

A GPIO implementation is very suitable as well for debugging: it can use
interrupts to detect state changes and report it. Userspace can then verify
if the bus traffic is correct. This also makes error injection possible.

The disadvantage is that it is hard to get the timings right since linux
isn't a hard realtime system.

In general on an idle system it works quite well, but under load the timer
will miss its mark every so often.

The debugfs file /sys/kernel/debug/cec/cecX/status gives some statistics
with respect to the timer overruns.

When the adapter is unconfigured and the low-level driver supports
interrupts, then the interrupt will be used to detect changes. This should
be quite accurate. But when the adapter is configured a hrtimer has to be
used.

The hrtimer implements a state machine where for each state the code will
read the bus or drive the bus and go on to the next state. It will re-arm
the timer with a delay based on the next state.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:57:18 -03:00
Hans Verkuil b8d62f50b1 media: cec: add core support for low-level CEC pin monitoring
Add support for the new MONITOR_PIN mode.

Add the cec_pin_event function that the CEC pin code will call to queue pin
change events.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:55:38 -03:00
Hans Verkuil 6b2bbb0874 media: cec: rework the cec event handling
Event handling was always fairly simplistic since there were only
two events. With the addition of pin events this needed to be redesigned.

The state_change and lost_msgs events are now core events with the
guarantee that the last state is always available. The new pin events
are a queue of events (up to 64 for each event) and the oldest event
will be dropped if the application cannot keep up. Lost events are
marked with a new event flag.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:49:36 -03:00
Hans Verkuil e6259b5f7a media: cec: add adap_free op
This is needed for CEC adapters that allocate resources that have
to be freed before the cec_adapter is deleted.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:47:29 -03:00
Hans Verkuil 0861ad14c6 media: cec: add *_ts variants for transmit_done/received_msg
Currently the transmit_(attempt_)done and received_msg functions set
the timestamp themselves. For the upcoming low-level pin API we need
to pass this as an argument instead. So make _ts variants that allow
the caller to specify the timestamp.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:47:02 -03:00
Hans Verkuil bb789e03f2 media: cec: improve transmit timeout logging
Kernel logging messes up the upcoming low-level CEC monitoring support
which is very time-sensitive. So change the debug level of this message
but keep a counter that is shown in the debugfs status log.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-07-18 12:45:50 -03:00
Mauro Carvalho Chehab ff6ccad361 Linux 4.12-rc6
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Merge tag 'v4.12-rc6' into patchwork

Linux 4.12-rc6

* tag 'v4.12-rc6': (813 commits)
  Linux 4.12-rc6
  mm: larger stack guard gap, between vmas
  virtio_balloon: disable VIOMMU support
  mm: correct the comment when reclaimed pages exceed the scanned pages
  userfaultfd: shmem: handle coredumping in handle_userfault()
  mm: numa: avoid waiting on freed migrated pages
  swap: cond_resched in swap_cgroup_prepare()
  mm/memory-failure.c: use compound_head() flags for huge pages
  perf unwind: Report module before querying isactivation in dwfl unwind
  fs: pass on flags in compat_writev
  objtool: Add fortify_panic as __noreturn function
  powerpc/debug: Add missing warn flag to WARN_ON's non-builtin path
  USB: gadgetfs, dummy-hcd, net2280: fix locking for callbacks
  drm: mxsfb_crtc: Reset the eLCDIF controller
  drm/mgag200: Fix to always set HiPri for G200e4 V2
  i2c: ismt: fix wrong device address when unmap the data buffer
  i2c: rcar: use correct length when unmapping DMA
  powerpc/xive: Fix offset for store EOI MMIOs
  drm/tegra: Correct idr_alloc() minimum id
  drm/tegra: Fix lockup on a use of staging API
  ...

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-20 08:51:56 -03:00
Hans Verkuil f902c1e95d [media] cec: add CEC_CAP_NEEDS_HPD
Add a new capability CEC_CAP_NEEDS_HPD. If this capability is set
then the hardware can only use CEC if the HDMI Hotplug Detect pin
is high. Such hardware cannot handle the corner case in the CEC specification
where it is possible to transmit messages even if no hotplug signal is
present (needed for some displays that turn off the HPD when in standby,
but still have CEC enabled).

Typically hardware that needs this capability have the HPD wired to the CEC
block, often to a 'power' or 'active' pin.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-20 06:54:34 -03:00
Hans Verkuil c94cdc1e0c [media] cec: add cec_transmit_attempt_done helper function
A simpler variant of cec_transmit_done to be used where the HW does
just a single attempt at a transmit. So if the status indicates an
error, then the corresponding error count will always be 1 and this
function figures that out based on the status argument.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-20 06:52:33 -03:00
Hans Verkuil 135327899d [media] cec: add cec_phys_addr_invalidate() helper function
Simplifies setting the physical address to CEC_PHYS_ADDR_INVALID.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-20 06:51:58 -03:00
Hans Verkuil 23111ec304 [media] cec: add cec_s_phys_addr_from_edid helper function
This function simplifies the integration of CEC in DRM drivers.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-20 06:51:21 -03:00
Hans Verkuil f9f314f323 [media] media/cec.h: use IS_REACHABLE instead of IS_ENABLED
Fix messages like this:

adv7842.c:(.text+0x2edadd): undefined reference to `cec_unregister_adapter'

when CEC_CORE=m but the driver including media/cec.h is built-in. In that case
the static inlines provided in media/cec.h should be used by that driver.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-08 16:52:28 -03:00
Hans Verkuil e94c32818d [media] cec: rename MEDIA_CEC_NOTIFIER to CEC_NOTIFIER
This config option is strictly speaking independent of the
media subsystem since it can be used by drm as well.

Besides, it looks odd when drivers select CEC_CORE and
MEDIA_CEC_NOTIFIER, that's inconsistent naming.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-06-04 15:23:35 -03:00
Hans Verkuil ee7e987133 [media] cec.h: merge cec-edid.h into cec.h
Drop the separate cec-edid.h header and merge it into cec.h.

There was really no need to have a separate header for this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-04-19 06:53:18 -03:00
Hans Verkuil 56a263aaa0 [media] cec: Kconfig cleanup
The Kconfig options for the CEC subsystem were a bit messy. In
addition there were two cec sources (cec-edid.c and cec-notifier.c)
that were outside of the media/cec directory, which was weird.

Move those sources to media/cec as well.

The cec-edid and cec-notifier functionality is now part of the cec
module and these are no longer separate modules.

Also remove the MEDIA_CEC_EDID config option and include it with the
main CEC config option (which defined CEC_EDID anyway).

Added static inlines to cec-edid.h for dummy functions when CEC_CORE
isn't defined.

CEC drivers should now depend on CEC_CORE.

CEC drivers that need the cec-notifier functionality must explicitly
select CEC_NOTIFIER.

The s5p-cec and stih-cec drivers depended on VIDEO_DEV instead of
CEC_CORE, fix that as well.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-04-19 06:50:52 -03:00
Hans Verkuil e3a93adcc4 [media] cec: integrate CEC notifier support
Support the CEC notifier framework, simplifying drivers that
depend on this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-04-10 12:49:19 -03:00
Jose Abreu 0b0b97dcc7 [media] cec: Add cec_get_drvdata()
Add a helper function to get driver private data from CEC
adapter. This helps the readability a little bit and allows
to change the 'priv' field name to something else without
needing to touch all drivers.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-04-05 15:17:58 -03:00
Hans Verkuil f51e80804f [media] cec: pass parent device in register(), not allocate()
The cec_allocate_adapter function doesn't need the parent device, only the
cec_register_adapter function needs it.

Drop the cec_devnode parent field, since devnode.dev.parent can be used
instead.

This change makes the framework consistent with other frameworks where the
parent device is not used until the device is registered.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-29 12:07:17 -02:00
Hans Verkuil 0dbacebede [media] cec: move the CEC framework out of staging and to media
The last open issues have been addressed, so it is time to move
this out of staging and into the mainline and to move the public
cec headers to include/uapi/linux.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-11-16 15:40:20 -02:00
Hans Verkuil 62148f0930 [media] cec: rename cec_devnode fhs_lock to just lock
This lock will be used to protect more than just the fhs list.
So rename it to just 'lock'.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-08-22 13:09:06 -03:00
Hans Verkuil 11065f8531 [media] cec: limit the size of the transmit queue
The size of the transmit queue was unlimited, which meant that
in non-blocking mode you could flood the CEC adapter with messages
to be transmitted.

Limit this to 18 messages.

Also print the number of pending transmits and the timeout value
in the status debugfs file.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-07-19 13:25:32 -03:00