[RFC PATCH 0/3] Google Chameleon v3 video driver

From: Paweł Anikiel
Date: Fri Jun 30 2023 - 10:40:36 EST


The Google Chameleon v3 is a testing device for external displays. It
is based on an Arria 10 SoCFPGA. This patch adds a V4L2 driver for the
video system. The video system consists of:
* Six video interfaces (DMA ping pong buffers) in the FPGA, called
"framebuffers".
* Two Intel DisplayPort DPRX IP cores in the FPGA, one MST x4, one SST
* IT68051 chip, handled by EC firmware

The driver is implemented as a single device driver, because the video
interface devices need to talk to the DisplayPort IP core devices
(e.g. to configure the EDID). This has the effect of the DPRX driver
being in the chameleonv3 directory even though it's an Intel IP.

The DPRX code handles all the AUX communication (DPCD, sideband messages,
message transfers). There is similarity to what's already present in
the DRM subsystem, but I found it hard to reuse that code effectively.

My main concern is with the overall structure of the driver - how it's
divided into parts, the interfaces and APIs used, etc. Any feedback is
greately appreciated.

Paweł Anikiel (3):
media: Add 10, 12, and 16 bit RGB formats
media: Add Google Chameleon v3 video driver
ARM: dts: Add Chameleon v3 video node

.../socfpga/socfpga_arria10_chameleonv3.dts | 54 ++
drivers/media/platform/Kconfig | 1 +
drivers/media/platform/Makefile | 1 +
drivers/media/platform/google/Kconfig | 4 +
drivers/media/platform/google/Makefile | 2 +
.../media/platform/google/chameleonv3/Kconfig | 9 +
.../platform/google/chameleonv3/Makefile | 15 +
.../platform/google/chameleonv3/chv3-core.c | 292 ++++++++++
.../platform/google/chameleonv3/chv3-core.h | 17 +
.../platform/google/chameleonv3/chv3-fb.c | 539 ++++++++++++++++++
.../platform/google/chameleonv3/chv3-fb.h | 34 ++
.../platform/google/chameleonv3/dprx-aux.c | 77 +++
.../platform/google/chameleonv3/dprx-dp.c | 82 +++
.../platform/google/chameleonv3/dprx-dpcd.c | 424 ++++++++++++++
.../platform/google/chameleonv3/dprx-dprx.c | 262 +++++++++
.../platform/google/chameleonv3/dprx-edid.c | 39 ++
.../platform/google/chameleonv3/dprx-i2c.c | 41 ++
.../platform/google/chameleonv3/dprx-mt.c | 184 ++++++
.../platform/google/chameleonv3/dprx-sbmsg.c | 162 ++++++
.../media/platform/google/chameleonv3/dprx.h | 128 +++++
drivers/media/v4l2-core/v4l2-ioctl.c | 5 +
include/uapi/linux/videodev2.h | 5 +
22 files changed, 2377 insertions(+)
create mode 100644 drivers/media/platform/google/Kconfig
create mode 100644 drivers/media/platform/google/Makefile
create mode 100644 drivers/media/platform/google/chameleonv3/Kconfig
create mode 100644 drivers/media/platform/google/chameleonv3/Makefile
create mode 100644 drivers/media/platform/google/chameleonv3/chv3-core.c
create mode 100644 drivers/media/platform/google/chameleonv3/chv3-core.h
create mode 100644 drivers/media/platform/google/chameleonv3/chv3-fb.c
create mode 100644 drivers/media/platform/google/chameleonv3/chv3-fb.h
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-aux.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-dp.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-dpcd.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-dprx.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-edid.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-i2c.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-mt.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx-sbmsg.c
create mode 100644 drivers/media/platform/google/chameleonv3/dprx.h

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2.41.0.255.g8b1d071c50-goog