.../media/platform/qcom/camss/camss-csid-gen2.c | 1 + drivers/media/platform/qcom/camss/camss-csid.c | 8 +- drivers/media/platform/qcom/camss/camss-csid.h | 1 + .../platform/qcom/camss/camss-csiphy-3ph-1-0.c | 243 +++++++++++++++++---- drivers/media/platform/qcom/camss/camss-csiphy.c | 6 +- drivers/media/platform/qcom/camss/camss-csiphy.h | 2 + drivers/media/platform/qcom/camss/camss.c | 36 ++- drivers/media/platform/qcom/camss/camss.h | 2 +- 8 files changed, 236 insertions(+), 63 deletions(-)
Note: WIP tag added, as not everything from the previous review round has
been addressed.
# Short summary
This patch series extends the Qualcomm CAMSS (Camera Subsystem),
including CSID and CSIPHY components, to support C-PHY mode configuration.
# Background and motivation
Modern smartphone cameras increasingly rely on MIPI C-PHY rather than
D-PHY, thanks to its higher data throughput and signal efficiency.
As a result, many OEMs adopt C-PHY interfaces for main (rear) cameras on
Qualcomm-based devices.
Until now, mainline Linux lacked C-PHY configuration support for Qualcomm
chipsets, preventing bring-up of primary camera sensors on several
Snapdragon platforms. This series closes that gap.
- Introduces C-PHY configuration support for the CAMSS driver stack,
covering both CSID and CSIPHY blocks.
- Successfully enables C-PHY operation on the Snapdragon 845 platform.
- Tested on OnePlus 6 and 6T phones running mainline Linux,
using the Sony IMX519 main camera sensor.
- The new configuration allows other chipsets versionsto enable C-PHY by
simply adding corresponding sensor driver support and csiphy
initialization data, following the example set for sdm845.
With this patch series, mainline Linux gains working C-PHY support for
Snapdragon 845, paving the way for improved main camera functionality
across many Qualcomm-based devices. The groundwork also simplifies
future enablement efforts for additional SoCs and sensors.
Until merged, the series will be also available at:
https://codeberg.org/sdm845/linux/commits/branch/b4/qcom-cphy
Signed-off-by: David Heidelberg <david@ixit.cz>
---
Changes in v6:
- lanes_enable now uses WARN_ONCE instead of return values. (Sakari)
- Dropped Kodiak patch until it gets better documented.
- Document the 3ph C-PHY sdm845 registers a bit.
- Link to v5: https://lore.kernel.org/r/20260531-qcom-cphy-v5-0-6be0f62b4d65@ixit.cz
Changes in v5:
- Split first patch enabling C-PHY part into last patch. (Bryan)
- Fix the camss_get_link_freq crash. (Cory)
- Dropped patch whitelisting C-PHY, instead use nullptr check. (Bryan)
- Dropped A-b/R-b from
"media: qcom: camss: Initialize lanes after lane configuration is available"
and changed Petr to Co-developed by and owned the patch.
- Link to v4: https://lore.kernel.org/r/20260301-qcom-cphy-v4-0-e53316d2cc65@ixit.cz
Changes in v4:
- Documented cphy parametr to camss_get_link_freq.
- Use BIT() macro for lane_mask. (Bryan)
- Correct lane_mask calculation. (Kieran + me)
- Removed comment for the D/C-PHY sequences init. (Bryan)
- Pass &csid->phy for calculate freq. (Bryan)
- Added missing cphy description to camss_get_link_freq. (kernel test robot)
- Gen2 v1.1 MIPI CSI-2 CPHY init hex to lowercase.
- Added back missed commit with improved electrical for sdm845 3ph.
- NOT addressed yet:
- Proliferating special cases in switch statements on a per-SoC basis is verboten.
- is it possible to set clock_lane to say 0xff in DT ?
- Link to v3: https://lore.kernel.org/r/20260117-qcom-cphy-v3-0-8ce76a06f7db@ixit.cz
Changes in v3:
- Make lanes_enable return sucess or error, since I couldn't move the
configuration to the _init.
- Dropped R-b tags on
"media: qcom: camss: Initialize lanes after lane configuration is available"
as I changed formatting.
- Link to v2: https://lore.kernel.org/r/20251204-qcom-cphy-v2-0-6b35ef8b071e@ixit.cz
Changes in v2:
- This is still WIP patch series, thus I wanted to publish already
changed parts to get feedback regarding to the direction of patchset.
- When switch to using odd bits, zeroed val which was left unitialized in v1.
- Accidentally missed archs added back in the commit moving lane regs to
new location.
- Remove commit with reverting check for only D-PHY is supported and
adjusted the check to also account for C-PHY.
- Documented link frequency calculation with defines. (Casey)
- Changed the cphy boolean to phy_cfg enum in the camss/camss-csiphy.
(Brian)
- Added patch for csiphy-3ph enablement for sm7280 from Luca as I'm
meanwhile trying to bring up the C-PHY sensor on FairPhone 5.
- Merged these two commits together
csiphy-3ph: Enable sdm845 C-PHY sequence
csiphy-3ph: Add Gen2 v1.1 MIPI CSI-2 CPHY init
merged R-b.
- Link to v1: https://lore.kernel.org/r/20251109-qcom-cphy-v1-0-165f7e79b0e1@ixit.cz
---
David Heidelberg (8):
media: qcom: camss: csiphy: Introduce PHY configuration
media: qcom: camss: csiphy-3ph: Use odd bits for configuring C-PHY lanes
media: qcom: camss: Prepare CSID for C-PHY support
media: qcom: camss: Initialize lanes after lane configuration is available
media: qcom: camss: csiphy-3ph: Add Gen2 v1.1 MIPI CSI-2 C-PHY init
media: qcom: camss: csiphy-3ph: Update Gen2 v1.1 MIPI CSI-2 C-PHY init
media: qcom: camss: Account for C-PHY when calculating link frequency
media: qcom: camss: Enable C-PHY where available
.../media/platform/qcom/camss/camss-csid-gen2.c | 1 +
drivers/media/platform/qcom/camss/camss-csid.c | 8 +-
drivers/media/platform/qcom/camss/camss-csid.h | 1 +
.../platform/qcom/camss/camss-csiphy-3ph-1-0.c | 243 +++++++++++++++++----
drivers/media/platform/qcom/camss/camss-csiphy.c | 6 +-
drivers/media/platform/qcom/camss/camss-csiphy.h | 2 +
drivers/media/platform/qcom/camss/camss.c | 36 ++-
drivers/media/platform/qcom/camss/camss.h | 2 +-
8 files changed, 236 insertions(+), 63 deletions(-)
---
base-commit: b7bee4ca5688e30ca50fbc87b1b8f7eed7006c17
change-id: 20251109-qcom-cphy-bb8cbda1c644
Best regards,
--
David Heidelberg <david@ixit.cz>
On 03/06/2026 00:30, David Heidelberg via B4 Relay wrote: > Note: WIP tag added, as not everything from the previous review round has > been addressed. > > # Short summary > > This patch series extends the Qualcomm CAMSS (Camera Subsystem), > including CSID and CSIPHY components, to support C-PHY mode configuration. > > # Background and motivation > > Modern smartphone cameras increasingly rely on MIPI C-PHY rather than > D-PHY, thanks to its higher data throughput and signal efficiency. > As a result, many OEMs adopt C-PHY interfaces for main (rear) cameras on > Qualcomm-based devices. > > Until now, mainline Linux lacked C-PHY configuration support for Qualcomm > chipsets, preventing bring-up of primary camera sensors on several > Snapdragon platforms. This series closes that gap. > > - Introduces C-PHY configuration support for the CAMSS driver stack, > covering both CSID and CSIPHY blocks. > - Successfully enables C-PHY operation on the Snapdragon 845 platform. > - Tested on OnePlus 6 and 6T phones running mainline Linux, > using the Sony IMX519 main camera sensor. > - The new configuration allows other chipsets versionsto enable C-PHY by > simply adding corresponding sensor driver support and csiphy > initialization data, following the example set for sdm845. > > With this patch series, mainline Linux gains working C-PHY support for > Snapdragon 845, paving the way for improved main camera functionality > across many Qualcomm-based devices. The groundwork also simplifies > future enablement efforts for additional SoCs and sensors. > > Until merged, the series will be also available at: > https://codeberg.org/sdm845/linux/commits/branch/b4/qcom-cphy > > Signed-off-by: David Heidelberg <david@ixit.cz> > --- > Changes in v6: > - lanes_enable now uses WARN_ONCE instead of return values. (Sakari) > - Dropped Kodiak patch until it gets better documented. > - Document the 3ph C-PHY sdm845 registers a bit. > - Link to v5: https://lore.kernel.org/r/20260531-qcom-cphy-v5-0-6be0f62b4d65@ixit.cz > > Changes in v5: > - Split first patch enabling C-PHY part into last patch. (Bryan) > - Fix the camss_get_link_freq crash. (Cory) > - Dropped patch whitelisting C-PHY, instead use nullptr check. (Bryan) > - Dropped A-b/R-b from > "media: qcom: camss: Initialize lanes after lane configuration is available" > and changed Petr to Co-developed by and owned the patch. > - Link to v4: https://lore.kernel.org/r/20260301-qcom-cphy-v4-0-e53316d2cc65@ixit.cz > > Changes in v4: > - Documented cphy parametr to camss_get_link_freq. > - Use BIT() macro for lane_mask. (Bryan) > - Correct lane_mask calculation. (Kieran + me) > - Removed comment for the D/C-PHY sequences init. (Bryan) > - Pass &csid->phy for calculate freq. (Bryan) > - Added missing cphy description to camss_get_link_freq. (kernel test robot) > - Gen2 v1.1 MIPI CSI-2 CPHY init hex to lowercase. > - Added back missed commit with improved electrical for sdm845 3ph. > - NOT addressed yet: > - Proliferating special cases in switch statements on a per-SoC basis is verboten. > - is it possible to set clock_lane to say 0xff in DT ? > - Link to v3: https://lore.kernel.org/r/20260117-qcom-cphy-v3-0-8ce76a06f7db@ixit.cz > > Changes in v3: > - Make lanes_enable return sucess or error, since I couldn't move the > configuration to the _init. > - Dropped R-b tags on > "media: qcom: camss: Initialize lanes after lane configuration is available" > as I changed formatting. > - Link to v2: https://lore.kernel.org/r/20251204-qcom-cphy-v2-0-6b35ef8b071e@ixit.cz > > Changes in v2: > - This is still WIP patch series, thus I wanted to publish already > changed parts to get feedback regarding to the direction of patchset. > - When switch to using odd bits, zeroed val which was left unitialized in v1. > - Accidentally missed archs added back in the commit moving lane regs to > new location. > - Remove commit with reverting check for only D-PHY is supported and > adjusted the check to also account for C-PHY. > - Documented link frequency calculation with defines. (Casey) > - Changed the cphy boolean to phy_cfg enum in the camss/camss-csiphy. > (Brian) > - Added patch for csiphy-3ph enablement for sm7280 from Luca as I'm > meanwhile trying to bring up the C-PHY sensor on FairPhone 5. > - Merged these two commits together > csiphy-3ph: Enable sdm845 C-PHY sequence > csiphy-3ph: Add Gen2 v1.1 MIPI CSI-2 CPHY init > merged R-b. > - Link to v1: https://lore.kernel.org/r/20251109-qcom-cphy-v1-0-165f7e79b0e1@ixit.cz > > --- > David Heidelberg (8): > media: qcom: camss: csiphy: Introduce PHY configuration > media: qcom: camss: csiphy-3ph: Use odd bits for configuring C-PHY lanes > media: qcom: camss: Prepare CSID for C-PHY support > media: qcom: camss: Initialize lanes after lane configuration is available > media: qcom: camss: csiphy-3ph: Add Gen2 v1.1 MIPI CSI-2 C-PHY init > media: qcom: camss: csiphy-3ph: Update Gen2 v1.1 MIPI CSI-2 C-PHY init > media: qcom: camss: Account for C-PHY when calculating link frequency > media: qcom: camss: Enable C-PHY where available > > .../media/platform/qcom/camss/camss-csid-gen2.c | 1 + > drivers/media/platform/qcom/camss/camss-csid.c | 8 +- > drivers/media/platform/qcom/camss/camss-csid.h | 1 + > .../platform/qcom/camss/camss-csiphy-3ph-1-0.c | 243 +++++++++++++++++---- > drivers/media/platform/qcom/camss/camss-csiphy.c | 6 +- > drivers/media/platform/qcom/camss/camss-csiphy.h | 2 + > drivers/media/platform/qcom/camss/camss.c | 36 ++- > drivers/media/platform/qcom/camss/camss.h | 2 +- > 8 files changed, 236 insertions(+), 63 deletions(-) > --- > base-commit: b7bee4ca5688e30ca50fbc87b1b8f7eed7006c17 > change-id: 20251109-qcom-cphy-bb8cbda1c644 > > Best regards, I'd like to see a dts to go with this ideally for upstream ... --- bod
On 03/06/2026 12:03, Bryan O'Donoghue wrote:
[...]
>> ---
>> David Heidelberg (8):
>> media: qcom: camss: csiphy: Introduce PHY configuration
>> media: qcom: camss: csiphy-3ph: Use odd bits for configuring C-PHY lanes
>> media: qcom: camss: Prepare CSID for C-PHY support
>> media: qcom: camss: Initialize lanes after lane configuration is available
>> media: qcom: camss: csiphy-3ph: Add Gen2 v1.1 MIPI CSI-2 C-PHY init
>> media: qcom: camss: csiphy-3ph: Update Gen2 v1.1 MIPI CSI-2 C-PHY init
>> media: qcom: camss: Account for C-PHY when calculating link frequency
>> media: qcom: camss: Enable C-PHY where available
>>
>> .../media/platform/qcom/camss/camss-csid-gen2.c | 1 +
>> drivers/media/platform/qcom/camss/camss-csid.c | 8 +-
>> drivers/media/platform/qcom/camss/camss-csid.h | 1 +
>> .../platform/qcom/camss/camss-csiphy-3ph-1-0.c | 243 +++++++++++++++++----
>> drivers/media/platform/qcom/camss/camss-csiphy.c | 6 +-
>> drivers/media/platform/qcom/camss/camss-csiphy.h | 2 +
>> drivers/media/platform/qcom/camss/camss.c | 36 ++-
>> drivers/media/platform/qcom/camss/camss.h | 2 +-
>> 8 files changed, 236 insertions(+), 63 deletions(-)
>> ---
>> base-commit: b7bee4ca5688e30ca50fbc87b1b8f7eed7006c17
>> change-id: 20251109-qcom-cphy-bb8cbda1c644
>>
>> Best regards,
>
> I'd like to see a dts to go with this ideally for upstream ...
>
> ---
> bod
There are two paths:
1. hardcoded driver (not going to be upstreamed, but works today with libcamera)
- sdm845-next git tree[1] (imx519 camera for sdm845-oneplus-common.dtsi)
2. mipi-ccs driver (tested locally with imx519 on D-PHY, but doesn't with C-PHY
yet or we haven't found right frequency which mipi-ccs would agree on)
a. needs C-PHY div/multiplier fix (I assume)
b. needs metadata patches until [2] get merged
c. needs initial sequence to be uploaded and packaged for distros
d. needs libcamera integration
David
[1] https://codeberg.org/sdm845/linux
[2] https://git.linuxtv.org/sailus/media_tree.git/log/?h=metadata
--
David Heidelberg
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