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Merge tag 'media/v6.2-1' of git://git.kernel.org/pub/scm/linux/kernel…
…/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: - DVB core changes to avoid refcount troubles and UAF - DVB API/core has gained support for DVB-C2 and DVB-S2X - New sensor drivers: ov08x40, ov4689.c, st-vgxy61 and tc358746.c - Removal of an unused sensor driver: s5k4ecgx - Move microchip_csi2dc to a new directory, named after the manufacturer - Add media controller support to Microship drivers - Old Atmel/Microship drivers that don't use media controler got moved to staging - New drivers added for Renesas RZ/G2L CRU and MIPI CSI-2 support - Allwinner A31 camera sensor driver code was now split into a bridge and a separate processor driver - Added a virtual stateless decoder driver in order to test core support for stateless drivers and test userspace apps using it - removed platform-based support for ov9650, as this is not used anymore - atomisp now uses videobuf2 and supports normal mmap mode - the imx7-media-csi driver got promoted from staging - rcar-vin driver has gained support for gen3 UDS (Up Down Scaler) - most i2c drivers now use I2C .probe_new() kAPI - lots of drivers fixes, cleanups and improvements * tag 'media/v6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (544 commits) media: s5c73m3: Switch to GPIO descriptors media: i2c: s5k5baf: switch to using gpiod API media: i2c: s5k6a3: switch to using gpiod API media: imx: remove code for non-existing config IMX_GPT_ICAP media: si470x: Fix use-after-free in si470x_int_in_callback() media: staging: stkwebcam: Restore MEDIA_{USB,CAMERA}_SUPPORT dependencies media: coda: Add check for kmalloc media: coda: Add check for dcoda_iram_alloc dt-bindings: media: s5c73m3: Fix reset-gpio descriptor media: dt-bindings: allwinner: h6-vpu-g2: Add IOMMU reference property media: s5k4ecgx: Delete driver media: s5k4ecgx: Switch to GPIO descriptors media: Switch to use dev_err_probe() helper headers: Remove some left-over license text in include/uapi/linux/v4l2-* headers: Remove some left-over license text in include/uapi/linux/dvb/ media: usb: pwc-uncompress: Use flex array destination for memcpy() media: s5p-mfc: Fix to handle reference queue during finishing media: s5p-mfc: Clear workbit to handle error condition media: s5p-mfc: Fix in register read and write for H264 media: imx: Use get_mbus_config instead of parsing upstream DT endpoints ...
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.. SPDX-License-Identifier: GPL-2.0 | ||
======== | ||
HDMI CEC | ||
======== | ||
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Supported hardware in mainline | ||
============================== | ||
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HDMI Transmitters: | ||
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- Exynos4 | ||
- Exynos5 | ||
- STIH4xx HDMI CEC | ||
- V4L2 adv7511 (same HW, but a different driver from the drm adv7511) | ||
- stm32 | ||
- Allwinner A10 (sun4i) | ||
- Raspberry Pi | ||
- dw-hdmi (Synopsis IP) | ||
- amlogic (meson ao-cec and ao-cec-g12a) | ||
- drm adv7511/adv7533 | ||
- omap4 | ||
- tegra | ||
- rk3288, rk3399 | ||
- tda998x | ||
- DisplayPort CEC-Tunneling-over-AUX on i915, nouveau and amdgpu | ||
- ChromeOS EC CEC | ||
- CEC for SECO boards (UDOO x86). | ||
- Chrontel CH7322 | ||
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HDMI Receivers: | ||
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- adv7604/11/12 | ||
- adv7842 | ||
- tc358743 | ||
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USB Dongles (see below for additional information on how to use these | ||
dongles): | ||
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- Pulse-Eight: the pulse8-cec driver implements the following module option: | ||
``persistent_config``: by default this is off, but when set to 1 the driver | ||
will store the current settings to the device's internal eeprom and restore | ||
it the next time the device is connected to the USB port. | ||
- RainShadow Tech. Note: this driver does not support the persistent_config | ||
module option of the Pulse-Eight driver. The hardware supports it, but I | ||
have no plans to add this feature. But I accept patches :-) | ||
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Miscellaneous: | ||
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- vivid: emulates a CEC receiver and CEC transmitter. | ||
Can be used to test CEC applications without actual CEC hardware. | ||
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- cec-gpio. If the CEC pin is hooked up to a GPIO pin then | ||
you can control the CEC line through this driver. This supports error | ||
injection as well. | ||
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Utilities | ||
========= | ||
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Utilities are available here: https://git.linuxtv.org/v4l-utils.git | ||
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``utils/cec-ctl``: control a CEC device | ||
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``utils/cec-compliance``: test compliance of a remote CEC device | ||
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``utils/cec-follower``: emulate a CEC follower device | ||
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Note that ``cec-ctl`` has support for the CEC Hospitality Profile as is | ||
used in some hotel displays. See http://www.htng.org. | ||
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Note that the libcec library (https://github.com/Pulse-Eight/libcec) supports | ||
the linux CEC framework. | ||
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If you want to get the CEC specification, then look at the References of | ||
the HDMI wikipedia page: https://en.wikipedia.org/wiki/HDMI. CEC is part | ||
of the HDMI specification. HDMI 1.3 is freely available (very similar to | ||
HDMI 1.4 w.r.t. CEC) and should be good enough for most things. | ||
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DisplayPort to HDMI Adapters with working CEC | ||
============================================= | ||
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Background: most adapters do not support the CEC Tunneling feature, | ||
and of those that do many did not actually connect the CEC pin. | ||
Unfortunately, this means that while a CEC device is created, it | ||
is actually all alone in the world and will never be able to see other | ||
CEC devices. | ||
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This is a list of known working adapters that have CEC Tunneling AND | ||
that properly connected the CEC pin. If you find adapters that work | ||
but are not in this list, then drop me a note. | ||
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To test: hook up your DP-to-HDMI adapter to a CEC capable device | ||
(typically a TV), then run:: | ||
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cec-ctl --playback # Configure the PC as a CEC Playback device | ||
cec-ctl -S # Show the CEC topology | ||
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The ``cec-ctl -S`` command should show at least two CEC devices, | ||
ourselves and the CEC device you are connected to (i.e. typically the TV). | ||
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General note: I have only seen this work with the Parade PS175, PS176 and | ||
PS186 chipsets and the MegaChips 2900. While MegaChips 28x0 claims CEC support, | ||
I have never seen it work. | ||
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USB-C to HDMI | ||
------------- | ||
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Samsung Multiport Adapter EE-PW700: https://www.samsung.com/ie/support/model/EE-PW700BBEGWW/ | ||
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Kramer ADC-U31C/HF: https://www.kramerav.com/product/ADC-U31C/HF | ||
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Club3D CAC-2504: https://www.club-3d.com/en/detail/2449/usb_3.1_type_c_to_hdmi_2.0_uhd_4k_60hz_active_adapter/ | ||
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DisplayPort to HDMI | ||
------------------- | ||
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Club3D CAC-1080: https://www.club-3d.com/en/detail/2442/displayport_1.4_to_hdmi_2.0b_hdr/ | ||
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CableCreation (SKU: CD0712): https://www.cablecreation.com/products/active-displayport-to-hdmi-adapter-4k-hdr | ||
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HP DisplayPort to HDMI True 4k Adapter (P/N 2JA63AA): https://www.hp.com/us-en/shop/pdp/hp-displayport-to-hdmi-true-4k-adapter | ||
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Mini-DisplayPort to HDMI | ||
------------------------ | ||
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Club3D CAC-1180: https://www.club-3d.com/en/detail/2443/mini_displayport_1.4_to_hdmi_2.0b_hdr/ | ||
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Note that passive adapters will never work, you need an active adapter. | ||
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The Club3D adapters in this list are all MegaChips 2900 based. Other Club3D adapters | ||
are PS176 based and do NOT have the CEC pin hooked up, so only the three Club3D | ||
adapters above are known to work. | ||
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I suspect that MegaChips 2900 based designs in general are likely to work | ||
whereas with the PS176 it is more hit-and-miss (mostly miss). The PS186 is | ||
likely to have the CEC pin hooked up, it looks like they changed the reference | ||
design for that chipset. | ||
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USB CEC Dongles | ||
=============== | ||
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These dongles appear as ``/dev/ttyACMX`` devices and need the ``inputattach`` | ||
utility to create the ``/dev/cecX`` devices. Support for the Pulse-Eight | ||
has been added to ``inputattach`` 1.6.0. Support for the Rainshadow Tech has | ||
been added to ``inputattach`` 1.6.1. | ||
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You also need udev rules to automatically start systemd services:: | ||
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SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="2548", ATTRS{idProduct}=="1002", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="pulse8-cec-inputattach@%k.service" | ||
SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="2548", ATTRS{idProduct}=="1001", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="pulse8-cec-inputattach@%k.service" | ||
SUBSYSTEM=="tty", KERNEL=="ttyACM[0-9]*", ATTRS{idVendor}=="04d8", ATTRS{idProduct}=="ff59", ACTION=="add", TAG+="systemd", ENV{SYSTEMD_WANTS}+="rainshadow-cec-inputattach@%k.service" | ||
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and these systemd services: | ||
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For Pulse-Eight make /lib/systemd/system/pulse8-cec-inputattach@.service:: | ||
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[Unit] | ||
Description=inputattach for pulse8-cec device on %I | ||
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[Service] | ||
Type=simple | ||
ExecStart=/usr/bin/inputattach --pulse8-cec /dev/%I | ||
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For the RainShadow Tech make /lib/systemd/system/rainshadow-cec-inputattach@.service:: | ||
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[Unit] | ||
Description=inputattach for rainshadow-cec device on %I | ||
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[Service] | ||
Type=simple | ||
ExecStart=/usr/bin/inputattach --rainshadow-cec /dev/%I | ||
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For proper suspend/resume support create: /lib/systemd/system/restart-cec-inputattach.service:: | ||
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[Unit] | ||
Description=restart inputattach for cec devices | ||
After=suspend.target | ||
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[Service] | ||
Type=forking | ||
ExecStart=/bin/bash -c 'for d in /dev/serial/by-id/usb-Pulse-Eight*; do /usr/bin/inputattach --daemon --pulse8-cec $d; done; for d in /dev/serial/by-id/usb-RainShadow_Tech*; do /usr/bin/inputattach --daemon --rainshadow-cec $d; done' | ||
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[Install] | ||
WantedBy=suspend.target | ||
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And run ``systemctl enable restart-cec-inputattach``. | ||
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To automatically set the physical address of the CEC device whenever the | ||
EDID changes, you can use ``cec-ctl`` with the ``-E`` option:: | ||
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cec-ctl -E /sys/class/drm/card0-DP-1/edid | ||
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This assumes the dongle is connected to the card0-DP-1 output (``xrandr`` will tell | ||
you which output is used) and it will poll for changes to the EDID and update | ||
the Physical Address whenever they occur. | ||
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To automatically run this command you can use cron. Edit crontab with | ||
``crontab -e`` and add this line:: | ||
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@reboot /usr/local/bin/cec-ctl -E /sys/class/drm/card0-DP-1/edid | ||
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This only works for display drivers that expose the EDID in ``/sys/class/drm``, | ||
such as the i915 driver. | ||
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CEC Without HPD | ||
=============== | ||
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Some displays when in standby mode have no HDMI Hotplug Detect signal, but | ||
CEC is still enabled so connected devices can send an <Image View On> CEC | ||
message in order to wake up such displays. Unfortunately, not all CEC | ||
adapters can support this. An example is the Odroid-U3 SBC that has a | ||
level-shifter that is powered off when the HPD signal is low, thus | ||
blocking the CEC pin. Even though the SoC can use CEC without a HPD, | ||
the level-shifter will prevent this from functioning. | ||
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There is a CEC capability flag to signal this: ``CEC_CAP_NEEDS_HPD``. | ||
If set, then the hardware cannot wake up displays with this behavior. | ||
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Note for CEC application implementers: the <Image View On> message must | ||
be the first message you send, don't send any other messages before. | ||
Certain very bad but unfortunately not uncommon CEC implementations | ||
get very confused if they receive anything else but this message and | ||
they won't wake up. | ||
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When writing a driver it can be tricky to test this. There are two | ||
ways to do this: | ||
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1) Get a Pulse-Eight USB CEC dongle, connect an HDMI cable from your | ||
device to the Pulse-Eight, but do not connect the Pulse-Eight to | ||
the display. | ||
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Now configure the Pulse-Eight dongle:: | ||
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cec-ctl -p0.0.0.0 --tv | ||
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and start monitoring:: | ||
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sudo cec-ctl -M | ||
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On the device you are testing run:: | ||
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cec-ctl --playback | ||
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It should report a physical address of f.f.f.f. Now run this | ||
command:: | ||
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cec-ctl -t0 --image-view-on | ||
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The Pulse-Eight should see the <Image View On> message. If not, | ||
then something (hardware and/or software) is preventing the CEC | ||
message from going out. | ||
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To make sure you have the wiring correct just connect the | ||
Pulse-Eight to a CEC-enabled display and run the same command | ||
on your device: now there is a HPD, so you should see the command | ||
arriving at the Pulse-Eight. | ||
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2) If you have another linux device supporting CEC without HPD, then | ||
you can just connect your device to that device. Yes, you can connect | ||
two HDMI outputs together. You won't have a HPD (which is what we | ||
want for this test), but the second device can monitor the CEC pin. | ||
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Otherwise use the same commands as in 1. | ||
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If CEC messages do not come through when there is no HPD, then you | ||
need to figure out why. Typically it is either a hardware restriction | ||
or the software powers off the CEC core when the HPD goes low. The | ||
first cannot be corrected of course, the second will likely required | ||
driver changes. | ||
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Microcontrollers & CEC | ||
====================== | ||
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We have seen some CEC implementations in displays that use a microcontroller | ||
to sample the bus. This does not have to be a problem, but some implementations | ||
have timing issues. This is hard to discover unless you can hook up a low-level | ||
CEC debugger (see the next section). | ||
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You will see cases where the CEC transmitter holds the CEC line high or low for | ||
a longer time than is allowed. For directed messages this is not a problem since | ||
if that happens the message will not be Acked and it will be retransmitted. | ||
For broadcast messages no such mechanism exists. | ||
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It's not clear what to do about this. It is probably wise to transmit some | ||
broadcast messages twice to reduce the chance of them being lost. Specifically | ||
<Standby> and <Active Source> are candidates for that. | ||
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Making a CEC debugger | ||
===================== | ||
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By using a Raspberry Pi 2B/3/4 and some cheap components you can make | ||
your own low-level CEC debugger. | ||
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Here is a picture of my setup: | ||
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https://hverkuil.home.xs4all.nl/rpi3-cec.jpg | ||
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It's a Raspberry Pi 3 together with a breadboard and some breadboard wires: | ||
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http://www.dx.com/p/diy-40p-male-to-female-male-to-male-female-to-female-dupont-line-wire-3pcs-356089#.WYLOOXWGN7I | ||
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Finally on of these HDMI female-female passthrough connectors (full soldering type 1): | ||
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https://elabbay.myshopify.com/collections/camera/products/hdmi-af-af-v1a-hdmi-type-a-female-to-hdmi-type-a-female-pass-through-adapter-breakout-board?variant=45533926147 | ||
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We've tested this and it works up to 4kp30 (297 MHz). The quality is not high | ||
enough to pass-through 4kp60 (594 MHz). | ||
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I also added an RTC and a breakout shield: | ||
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https://www.amazon.com/Makerfire%C2%AE-Raspberry-Module-DS1307-Battery/dp/B00ZOXWHK4 | ||
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https://www.dx.com/p/raspberry-pi-gpio-expansion-board-breadboard-easy-multiplexing-board-one-to-three-with-screw-for-raspberry-pi-2-3-b-b-2729992.html#.YGRCG0MzZ7I | ||
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These two are not needed but they make life a bit easier. | ||
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If you want to monitor the HPD line as well, then you need one of these | ||
level shifters: | ||
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https://www.adafruit.com/product/757 | ||
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(This is just where I got these components, there are many other places you | ||
can get similar things). | ||
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The CEC pin of the HDMI connector needs to be connected to these pins: | ||
CE0/IO8 and CE1/IO7 (pull-up GPIOs). The (optional) HPD pin of the HDMI | ||
connector should be connected (via a level shifter to convert the 5V | ||
to 3.3V) to these pins: IO17 and IO27. The (optional) 5V pin of the HDMI | ||
connector should be connected (via a level shifter) to these pins: IO22 | ||
and IO24. Monitoring the HPD an 5V lines is not necessary, but it is helpful. | ||
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This kernel patch will hook up the cec-gpio driver correctly to | ||
e.g. ``arch/arm/boot/dts/bcm2837-rpi-3-b-plus.dts``:: | ||
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cec-gpio@7 { | ||
compatible = "cec-gpio"; | ||
cec-gpios = <&gpio 7 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; | ||
hpd-gpios = <&gpio 17 GPIO_ACTIVE_HIGH>; | ||
v5-gpios = <&gpio 22 GPIO_ACTIVE_HIGH>; | ||
}; | ||
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cec-gpio@8 { | ||
compatible = "cec-gpio"; | ||
cec-gpios = <&gpio 8 (GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN)>; | ||
hpd-gpios = <&gpio 27 GPIO_ACTIVE_HIGH>; | ||
v5-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>; | ||
}; | ||
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This dts change will enable two cec GPIO devices: I typically use one to | ||
send/receive CEC commands and the other to monitor. If you monitor using | ||
an unconfigured CEC adapter then it will use GPIO interrupts which makes | ||
monitoring very accurate. | ||
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The documentation on how to use the error injection is here: :ref:`cec_pin_error_inj`. | ||
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``cec-ctl --monitor-pin`` will do low-level CEC bus sniffing and analysis. | ||
You can also store the CEC traffic to file using ``--store-pin`` and analyze | ||
it later using ``--analyze-pin``. | ||
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You can also use this as a full-fledged CEC device by configuring it | ||
using ``cec-ctl --tv -p0.0.0.0`` or ``cec-ctl --playback -p1.0.0.0``. |
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