[PATCH 0/6] phy: qcom: qmp-usbc: properly handle the clamping register

Dmitry Baryshkov dmitry.baryshkov at linaro.org
Mon Jan 15 17:08:26 PST 2024


The USB-C PHY on the MSM8998, QCM2290, SM6115 and several other platforms
doesn't have built-in PCS_MISC_CLAMP_ENABLE register. Instead clamping
is handled separately via the register in the TCSR space. Make the new
phy-qcom-qmp-usbc driver correctly handle the clamp register.

For backwards compatibility the driver treats these registers as
optional. They are only required for the PHY suspend/resume. However the
schema declares corresponding property as required, it should be present
on all relevant platforms.

At this point I'm not sure whether having a single TCSR-based register
will be enough or whether we will have to add more TCSR registers in
future. In order to avoid repeating TCSR handle (and having multiple
instances of TCSR regmap in the driver) use qcom,tcsr-reg property
rather than someting more exact like qcom,vls-clamp-reg.

Dependecies: PHY-related changes of [1]

Note for the backporters: if the patch is packported to the kernel
before the phy-qocm-qmp-usbc split, the phy-qcom-qmp-usb driver needs to
handle both PCS_MISC_CLAMP_ENABLE and VLS_CLAMP registers as optional.

[1] https://lore.kernel.org/linux-arm-msm/20240113-pmi632-typec-v2-0-182d9aa0a5b3@linaro.org/

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
Dmitry Baryshkov (6):
      dt-bindings: mfd: qcom,tcsr: Add compatibles for QCM2290 and SM6115
      dt-bindings: phy: qcom,msm8998-qmp-usb3-phy: add TCSR registers
      phy: qcom: qmp-usbc: handle CLAMP register in a correct way
      arm64: dts: qcom: msm8998: declare VLS CLAMP register for USB3 PHY
      arm64: dts: qcom: qcm2290: declare VLS CLAMP register for USB3 PHY
      arm64: dts: qcom: sm6115: declare VLS CLAMP register for USB3 PHY

 .../devicetree/bindings/mfd/qcom,tcsr.yaml         |  2 +
 .../bindings/phy/qcom,msm8998-qmp-usb3-phy.yaml    | 11 +++++
 arch/arm64/boot/dts/qcom/msm8998.dtsi              |  2 +
 arch/arm64/boot/dts/qcom/qcm2290.dtsi              |  7 ++++
 arch/arm64/boot/dts/qcom/sm6115.dtsi               |  7 ++++
 drivers/phy/qualcomm/phy-qcom-qmp-usbc.c           | 48 +++++++++++++++++-----
 6 files changed, 66 insertions(+), 11 deletions(-)
---
base-commit: d0f9c0b672a974d32c40d369f63e441a7dd66d74
change-id: 20240116-usbc-phy-vls-clamp-10189efdcf12

Best regards,
-- 
Dmitry Baryshkov <dmitry.baryshkov at linaro.org>




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