Re: [PATCH v9 00/21] media: i2c: add Maxim GMSL2/3 serializer and deserializer drivers

[Ceclan Dumitru]

On 3/26/26 7:00 PM, Dayananda, Vivekananda wrote:
> [AMD Official Use Only - AMD Internal Distribution Only]
> 
> Hi Dumitru, Sakari,
> 
> Thank you for the latest patch series. We have been validating this
> on the following test infrastructure:
> 
> - IMX219 image sensor
> - MAX96724 deserializer
> - MAX96717 serializer
> 
> With this setup the v9 drivers operate as expected and we are able to
> exercise streaming end-to-end.
> 
> One item worth noting: our deserializer sits on a custom daughter card
> where the I2C bus is routed through port 1. The current MAX96724 driver
> only supports I2C on port 0. It would be valuable to extend the driver
> to support additional I2C port configurations so that setups like ours
> can be accommodated.
> 
> Vivek 

Hi Vivek,

I have found the EZ thread where the I2C port1 issue was raised and
resolved. Would the inclusion of those 2 commits from Cosmin suffice
or were there more changes required for your setup to work?


>> -----Original Message-----
>> From: Dumitru Ceclan via B4 Relay
>> <devnull+dumitru.ceclan.analog.com@xxxxxxxxxx>
>> Sent: Wednesday, March 11, 2026 12:17 AM
>> To: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>; Mauro
>> Carvalho Chehab <mchehab@xxxxxxxxxx>; Sakari Ailus
>> <sakari.ailus@xxxxxxxxxxxxxxx>; Laurent Pinchart
>> <laurent.pinchart@xxxxxxxxxxxxxxxx>; Julien Massot
>> <julien.massot@xxxxxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>; Niklas
>> Söderlund <niklas.soderlund@xxxxxxxxxxxx>; Greg Kroah-Hartman
>> <gregkh@xxxxxxxxxxxxxxxxxxx>; Cosmin Tanislav <cosmin.tanislav@xxxxxxxxxx>
>> Cc: mitrutzceclan@xxxxxxxxx; linux-media@xxxxxxxxxxxxxxx; linux-
>> kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-
>> staging@xxxxxxxxxxxxxxx; linux-gpio@xxxxxxxxxxxxxxx; Niklas Söderlund
>> <niklas.soderlund+renesas@xxxxxxxxxxxx>; Martin Hecht
>> <Martin.Hecht@xxxxxxxx>; Tomi Valkeinen
>> <tomi.valkeinen@xxxxxxxxxxxxxxxx>; Cosmin Tanislav
>> <demonsingur@xxxxxxxxx>; Cory Keitz <ckeitz@xxxxxxxxxx>
>> Subject: [PATCH v9 00/21] media: i2c: add Maxim GMSL2/3 serializer and
>> deserializer drivers
>>
>> This series adds new drivers for multiple Maxim GMSL2 and GMSL3 devices,
>> replacing the few GMSL2 drivers already in upstream, and introducing a common
>> framework that can be used to implement such GMSL chips, which avoids code
>> duplication while also adding support for previously unsupported features.
>>
>> While the normally acceptable and polite way would be to extend the current
>> mainline drivers, the choice was made here to add a totally new set of drivers.
>> The current drivers support only a small subset of the possible features, and only
>> a few devices, so the end result after extending them would in any case be
>> essentially fully rewritten, new drivers.
>>
>> This series depends on support for internal pads, for which a patch has been
>> added.
>>
>> The previous version is at:
>> https://lore.kernel.org/all/20250718152500.2656391-1-
>> demonsingur@xxxxxxxxx/
>>
>> Since the previous series, Cosmin has left Analog Devices.
>> Because included changes from previous version are trivial, his sign-off and tags
>> were retained.
>>
>> The following deserializers are supported:
>> * MAX96712 (already exists in staging)
>> * MAX96714 (already exists)
>> * MAX96714F (already exists)
>> * MAX96714R (GMSL2)
>> * MAX96716 (GMSL2)
>> * MAX96724 (already exists as part of existing MAX96712 driver)
>> * MAX96724F (GMSL2)
>> * MAX96724R (GMSL2)
>> * MAX9296A (GMSL2)
>> * MAX96792A (GMSL3)
>>
>> The following serializers are supported:
>> * MAX96717 (already exists)
>> * MAX9295A (GMSL2)
>> * MAX96793 (GMSL3)
>>
>> The following list enumerates new features that are supported by the common
>> framework and their respective chip-specific drivers:
>> * Full Streams API support. Most deserializers have support for more than one
>> link, and more than one PHY. Streams support allows configuration of routing
>> between these links and PHYs.
>>
>> * .get_frame_desc() support. Both the serializers and deserializers implement this
>> to query and provide frame descriptor data. This is used in features explained in-
>> depth below.
>>
>> * .get_mbus_config() support. The deserializers implement this to allow upstream
>> devices to query the link frequency of its pads.
>>
>> * Address translation with I2C ATR for the serializers.
>>
>> * I2C ATR translation - some deserializers cannot do muxing since I2C
>> communication channel masking is not available per-link, and the only other way
>> to select links is to turn them off, causing link resets.
>> For such cases, I2C ATR is used to change the address of the serializers at probe
>> time.
>>
>> * Automatic GMSL link version negotiation between GMSL3, GMSL2 6Gbps,
>> GMSL2 3Gbps.
>>
>> * Automatic stream id selection for deserializers which need serializers to stream
>> on unique stream ids.
>>
>> * Automatic VC remapping on the deserializers. VCs are picked so that if they
>> were unique on the sink pad, they will end up as unique on the source pad they
>> are routed to too, prioritizing using the same VC ID as the sink pad, to facilitate
>> the possibility of using tunnel mode.
>>
>> * Automatic pixel mode / tunnel mode selection. Tunnel mode is used when VC
>> IDs do not need to be changed and all hardware supports tunnel mode,
>> otherwise, pixel mode is used. The serializers are automatically switched
>> between the two by using a private API.
>>
>> * Automatic double mode selection. In pixel mode, double mode can be used to
>> pack two pixels into a single data unit, optimizing bandwidth usage. The
>> serializers are automatically set up to support the double modes determined by
>> the deserializers using a private API.
>>
>> * Automatic data padding. In pixel mode, if the data being transferred uses two
>> different BPPs, data needs to be padded. The serializers automatically set this up
>> depending on the configured double mode settings and incoming data types.
>>
>> * Logging. Both the deserializers and serializers implement the V4L2
>> .log_status() ops to allow debugging of the internal state and important chip
>> status registers.
>>
>> * PHY modes. Deserializer chips commonly have more than a single PHY.
>> The firmware ports are parsed to determine the modes in which to configure the
>> PHYs (2x4, 4x2, 1x4+2x2, 2x2+1x4, and variations using fewer lanes).
>>
>> * Serializer pinctrl. Serializers implement pinctrl to allow setting configs which
>> would otherwise be inaccessible through GPIO: TX/RX via GMSL link, pull-up &
>> pull-down (with strength), open-drain & push-pull, slew rate, RCLK pin selection.
>>
>> * TPG with selectable formats, resolutions and framerates for both serializers and
>> deserializers.
>>
>> The drivers have been tested on the following hardware combinations, but further
>> testing is welcome to ensure no / minimal breakage:
>> * Raspberry Pi 5 + MAX9296A + 2xMAX96717 + 2xIMX219
>> * Raspberry Pi 5 + MAX96714 + 1xMAX96717 + 1xIMX219
>> * Raspberry Pi 5 + MAX96716A + 2xMAX96717 + 2xIMX219
>> * Raspberry Pi 5 + MAX96712 + 4xMAX96717 + 4xIMX219
>> * Raspberry Pi 5 + MAX96724 + 4xMAX96717 + 4xIMX219
>> * Raspberry Pi 5 + MAX96792A + 1xMAX96793 + 1xMAX96717 + 2xIMX219
>> * Raspberry Pi 5 + MAX96792A + 2xMAX96717 + 2xIMX219
>> * Renesas V4H + MAX96712 + 2xMAX96717 + 2xIMX219
>>
>> Analog Devices is taking responsibility for the maintenance of these drivers and
>> common framework, and plans to add support for new broad-market chips on top
>> of them.
>>
>> Special thanks go to Tomi Valkeinen <
>> tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
>> for testing the drivers, helping debug and coming up with ideas / implementations
>> for various features.
>>
>> The following v4l2-compliance test still fails:
>>                 fail: v4l2-test-subdevs.cpp(371): fmt.code == 0 || fmt.code == ~0U
>>                 fail: v4l2-test-subdevs.cpp(418): checkMBusFrameFmt(node, fmt.format)
>>         test Active VIDIOC_SUBDEV_G/S_FMT: FAIL
>>
>> As the serializers and deserializers are format agnostic and the values set are not
>> used to configure anything in the chips, this test does not make much sense in this
>> context. If needed, a check for the specific ~0U value can be added.
>>
>> V9:
>> * split max_des_ops into *_info and *_ops
>> * use read_poll_timeout macro in *_wait_for_device()
>> * return read_poll_timeout error -ETIMEDOUT in *_wait_for_device()
>> * remove use_atr duplicate from max9296a_chip_info, present in max_des_info
>> * fix max9296a DPLL register offset
>> * fix C-PHY DPLL frequency in max9296a and max96724
>>     reported by: Cory Keitz <ckeitz@xxxxxxxxxx>
>> * use MAX9296A_COMMON_INFO and MAX9296A_COMMON_OPS to simplify
>>   probe ops init
>> * fix borked patches in previous version, actually remove MAX96717 and
>>   MAX96714 drivers
>>
>> V8:
>> * max96717: use the renamed PIN_CONFIG_OUTPUT to _LEVEL
>> * max96717: use the renamed set_rv ops from struct gpio_chip
>> * dt-bindings: set minItems lane-polarities to 2
>> * dt-bindings: "add myself as maintainer" commits were removed
>> * max_des & max_ser: use a default format for set_routing
>> * max_des & max_ser: return ENNOTTY in *_frame_interval for non-TPG pads
>>
>> V7:
>> * dt-bindings: max9296a: use full max96717 compatible
>> * max9296a: make max96714_rlms_reg_sequence static
>> * explicitly include linux/bitfield.h
>> * explicitly depend on I2C and PINCTRL
>> * sort media_entity_operations
>> * add has_pad_interdep to media_entity_operations
>>
>> V6:
>> * max9296a: put rlms sequence in max9296a_chip_info
>> * max_des: reflow stream id a comment
>> * max_ser: remove exported symbols not used in other modules
>> * max_ser: init mode to a supported value
>> * add default routing
>> * MAX_SERDES_GMSL_3 -> MAX_SERDES_GMSL_3_12GBPS
>> * guard reg_read/write with CONFIG_VIDEO_ADV_DEBUG
>> * put exported symbols in MAXIM_SERDES namespace
>>
>> V5:
>> * dt-bindings: max96717: restrict RCLKOUT to pins 2 & 4
>> * dt-bindings: max96717: remove confusing rclksel pinconf property
>> * dt-bindings: max96717: remove maxim,gmsl-tx/rx pinconf property
>> * dt-bindings: max96717: remove gmsl prefix from maxim,gmsl-tx-id/rx-id
>> * dt-bindings: max96717: remove minimum: 0
>> * dt-bindings: max96717: better document slew-rate
>> * dt-bindings: max96717: better document maxim,jitter-compensation
>> * dt-bindings: max96717: better document maxim,tx-id/rx-id
>>
>> * max_serdes: add default TPG values
>> * max_serdes: remove MAX_MIPI_FMT macro
>> * max_serdes: EXPORT_SYMBOL -> EXPORT_SYMBOL_GPL
>> * max_serdes: remove EXPORT_SYMBOL_GPL from symbols not used in other
>> modules
>> * max_serdes: rename symbols/macros/types to have max_serdes prefix
>> * max_serdes: slim down TPG functions
>>
>> * max_des: fix may be used uninitialized errors
>> * max_des: fix misplaced TPG validation
>> * max_des: fix setting pipe PHY in tunnel mode for chips that support both
>> set_pipe_phy() and set_pipe_tunnel_phy()
>> * max_des: move doubled_bpp/sink_bpps variables to usage place
>> * max_des: do not dynamically control PHY enable, letting lanes be in
>> LP-11 when not streaming
>> * max_des: refactor get/set_pipe_stream_id() logic
>> * max_des: remove explicit ret = 0
>>
>> * max_ser: make VC remaps not pipe-specific, allocate dynamically
>>
>> * max9296a: add missing 1080p30 TPG entry
>> * max9296a: move BIT() left shift into macro
>> * max9296a: move BIT() ternary into macro
>> * max9296a: reuse max_des_ops for chip-specific ops\
>> * max9296a: document and compress RLMS register writes
>>
>> * max96717: restrict RCLKOUT to pins 2 & 4 because of hardware capabilities
>> * max96717: add support for XTAL/1, XTAL/2, XTAL/4 clocks
>> * max96717: set RX_EN/TX_EN automatically
>> * max96717: reorder custom pinconf flags
>> * max96717: drop OF dependency
>>
>> * drop of_match_ptr
>> * re-do some indentation
>> * implement TPG pattern control
>> * remove pr_info() usage
>> * inline lane polarity val = 0
>> * inline returns
>> * rewrite some Kconfig docs
>> * split up patches for easier review
>>
>> V4:
>> * max_des: fix infinite version loop
>> * max_des: fix pipe link id when there are more pipes than links
>> * max_des: implement setting pipe link
>> * max_des: do not pass routing to phy update
>> * max_des: move GMSL version strings to max_serdes
>> * max_des: split finding existing VC remap from adding a new one
>> * max_des: add tracking for in-use pipes
>> * max_des: skip unused pipes when finding / setting pixel/tunnel mode
>> * max_des: simplify remap code
>> * max_des: split set_pipe_phy() into set_pipe_tunnel_phy()
>>
>> * max_ser: clean up i2c_xlates printing
>> * max_ser: fix changing serializer address
>> * max_ser: move non-continuous mode check into max96717 driver
>>
>> * max96724: use regmap_set_bits for STREAM_SEL_ALL
>> * max96724: match surrounding indent for MAX96724_PHY1_ALT_CLOCK
>> * max96724: fix setting invalid PHY to 1 when PHY 0 is in 4-lane mode
>> * max96724: remove support for setting pipe phy from max96712
>> * max96724: fix setting double mode on pipes 4-7
>> * max96724: drop powerdown gpios
>>
>> * max96717: use gpio_chip's set_rv
>>
>> * max9296a: switch versions to unsigned int
>> * max9296a: remove parantheses from MAX9296A_MIPI_PHY18/20
>> * max9296a: fix printing of PHY packet counts
>> * max9296a: fix phy_hw_ids size
>>
>> * remove usage of cammel case in defines
>> * move field_get/prep to max_serdes.h
>> * rework stream id setup
>> * rework tunnel/pixel mode finding
>> * rework bpps retrieval
>> * pass whole subdev state around
>> * add helper for retrieving a route's hw components / frame desc
>> * update pipe enable based on active routes
>> * add support for tunnel-only chips and VC remaps in tunnel mode
>> * simplify max_get_streams_masks()
>> * add support for TPG
>>
>> V3:
>> * dt-bindings: drop reflow text patches
>>
>> * dt-bindings: max96717: move pinctrl configuration into main file
>> * dt-bindings: max96717: allow a single level of pins configuration
>> * dt-bindings: max96717: use regex for matching pins nodes
>> * dt-bindings: max96717: drop extra allOf in pinctrl configuration
>> * dt-bindings: max96717: fix i2c-atr channel name regex
>> * dt-bindings: max96717: limit pinctrl functions to gpio / rclkout
>> * dt-bindings: max96717: limit pins for gpio / rclkout
>> * dt-bindings: max96717: add description for bias-pull-up/down
>> * dt-bindings: max96717: require pins and function properties
>> * dt-bindings: max96717: turn single compatible strings into an enum
>>
>> * dt-bindings: max9296a: include indices in port descriptions
>> * dt-bindings: max9296a: remove property-less schema from input ports
>> * dt-bindings: max9296a: use ATR for MAX96716A too, removing MUX entirely
>>
>> * dt-bindings: max96712: include indices in port descriptions
>> * dt-bindings: max96712: deprecate enable-gpios in favor of powerdown-gpios
>> * dt-bindings: max96712: switch from MUX to ATR
>>
>> * dt-bindings: max96714: add support for MAX96714R
>>
>> * max_des: fix POC NULL check
>> * max_des: remove index var in POC enable
>> * max_des: fix writing empty remaps
>> * max_des: skip mode setting in tunnel mode
>> * max_des: remove a duplicate source->sd NULL check
>> * max_des: set pipe tunnel mode even for disabled links
>>
>> * max_ser: apply TX ID changes irrespective of serializer ID
>>
>> * max9296a: fix typo in BACKTOP22
>> * max9296a: make register macros more consistent
>> * max9296a: switch MAX96716 from MUX to ATR
>> * max9296a: deduplicate max9296a_phy_id() logic
>> * max9296a: use proper PHY id in remaps
>> * max9296a: fix DPLL reset clear
>> * max9296a: limit MAX96714F to GMSL2 3Gbps
>> * max9296a: add support for MAX96714R
>> * max9296a: do not write GMSL3 link select registers in GMSL2 devices
>> * max9296a: use field_prep when setting RX_RATE
>> * max9296a: simplify setting SEL_STREAM for MAX96714
>> * max9296a: max96716_set_pipe_phy -> max96716a_set_pipe_phy
>> * max9296a: fix off-by-one in lane polarity when using
>> polarity_on_physical_lanes
>>
>> * max96724: fix typo in BACKTOP22
>> * max96724: switch from MUX to ATR
>> * max96724: add support for powerdown GPIO
>> * max96724: remove support for tunneling from MAX96712
>> * max96724: only set tunnel-related bits when in tunnel mode
>> * max96724: add support for MAX96724F/R
>> * max96724: oneshot reset links after link selection
>>
>> * remove GMSL2 version defaults, set all supported versions explicitly
>> * reorder GMSL versions to start from 0
>> * add support for GMSL2 3Gbps
>> * support GMSL version finding for devices using MUX / GATE
>> * add support for deserializers which don't have individual control of each link's
>> GMSL version
>> * add support for deserializers that need unique stream ids across all serializers
>> * select_link_version -> set_link_version
>> * select_resets_link -> use_atr
>>
>> V2:
>> * add missing compatible for MAX96717F
>> * fix embarrassing dt-bindings mistakes
>> * move MAX9296A/MAX96716/MAX96792A to a separate file as they have two
>> links / PHYs, and adding those conditionally seems impossible
>> ---
>> Cosmin Tanislav (20):
>>       dt-bindings: media: i2c: max96717: add support for I2C ATR
>>       dt-bindings: media: i2c: max96717: add support for pinctrl/pinconf
>>       dt-bindings: media: i2c: max96717: add support for MAX9295A
>>       dt-bindings: media: i2c: max96717: add support for MAX96793
>>       dt-bindings: media: i2c: max96712: use pattern properties for ports
>>       dt-bindings: media: i2c: max96712: add support for I2C ATR
>>       dt-bindings: media: i2c: max96712: add support for POC supplies
>>       dt-bindings: media: i2c: max96712: add support for MAX96724F/R
>>       dt-bindings: media: i2c: max96714: add support for MAX96714R
>>       dt-bindings: media: i2c: add MAX9296A, MAX96716A, MAX96792A
>>       media: i2c: add Maxim GMSL2/3 serializer and deserializer framework
>>       media: i2c: add Maxim GMSL2/3 serializer framework
>>       media: i2c: add Maxim GMSL2/3 deserializer framework
>>       media: i2c: maxim-serdes: add MAX96717 driver
>>       media: i2c: maxim-serdes: add MAX96724 driver
>>       media: i2c: maxim-serdes: add MAX9296A driver
>>       arm64: defconfig: disable deprecated MAX96712 driver
>>       staging: media: remove MAX96712 driver
>>       media: i2c: remove MAX96717 driver
>>       media: i2c: remove MAX96714 driver
>>
>> Sakari Ailus (1):
>>       media: mc: Add INTERNAL pad flag
>>
>>  .../bindings/media/i2c/maxim,max9296a.yaml         |  242 ++
>>  .../bindings/media/i2c/maxim,max96712.yaml         |   65 +-
>>  .../bindings/media/i2c/maxim,max96714.yaml         |    5 +-
>>  .../bindings/media/i2c/maxim,max96717.yaml         |  154 +-
>>  .../userspace-api/media/mediactl/media-types.rst   |    9 +
>>  MAINTAINERS                                        |   10 +-
>>  arch/arm64/configs/defconfig                       |    1 -
>>  drivers/media/i2c/Kconfig                          |   34 +-
>>  drivers/media/i2c/Makefile                         |    3 +-
>>  drivers/media/i2c/max96714.c                       | 1017 -------
>>  drivers/media/i2c/max96717.c                       | 1102 -------
>>  drivers/media/i2c/maxim-serdes/Kconfig             |   60 +
>>  drivers/media/i2c/maxim-serdes/Makefile            |    6 +
>>  drivers/media/i2c/maxim-serdes/max9296a.c          | 1358 +++++++++
>>  drivers/media/i2c/maxim-serdes/max96717.c          | 1686 +++++++++++
>>  drivers/media/i2c/maxim-serdes/max96724.c          | 1193 ++++++++
>>  drivers/media/i2c/maxim-serdes/max_des.c           | 3188
>> ++++++++++++++++++++
>>  drivers/media/i2c/maxim-serdes/max_des.h           |  156 +
>>  drivers/media/i2c/maxim-serdes/max_ser.c           | 2138 +++++++++++++
>>  drivers/media/i2c/maxim-serdes/max_ser.h           |  147 +
>>  drivers/media/i2c/maxim-serdes/max_serdes.c        |  413 +++
>>  drivers/media/i2c/maxim-serdes/max_serdes.h        |  183 ++
>>  drivers/media/mc/mc-entity.c                       |   15 +-
>>  drivers/staging/media/Kconfig                      |    2 -
>>  drivers/staging/media/Makefile                     |    1 -
>>  drivers/staging/media/max96712/Kconfig             |   14 -
>>  drivers/staging/media/max96712/Makefile            |    2 -
>>  drivers/staging/media/max96712/max96712.c          |  487 ---
>>  include/uapi/linux/media.h                         |    1 +
>>  29 files changed, 11006 insertions(+), 2686 deletions(-)
>> ---
>> base-commit: a15a902a91b78f1544760fb52ef0151f83815f81
>> change-id: 20251107-gmsl2-3_serdes-3f2b885209c3
>>
>> Best regards,