[PATCH 0/3] Add PMI8998 VBUS Regulator Support

James A. MacInnes
2025-02-11T19:49:46Z

Hello,

This patch series adds support for the PMI8998 VBUS regulator in the Qualcomm USB VBUS regulator driver and the device tree. These changes enable proper VBUS current limit configuration and ensure compatibility across multiple Qualcomm PMICs.

Summary of Changes:
- Patch 1/3: Updates the Device Tree Schema bindings to include "qcom,pmi8998-vbus-reg" for PMI8998 support.
- Patch 2/3: Extends the Qualcomm USB VBUS regulator driver to support PMI8998, dynamically configuring the regulator based on the PMIC type.
- Patch 3/3: Adds the VBUS regulator node to pmi8998.dtsi, enabling USB Type-C VBUS support.

Motivation:
A long time ago, in a conference room far, far away, I promised that USB Type-C capability would work on the SDM845 when we chose this chip for our instrument.

That day never came.

So I wrote it myself.

This patch series finally adds the missing support for USB Type-C VBUS regulation on PMI8998-based platforms. Future generations of engineers will no longer have to mutter "Why doesn’t this work?" while digging through device trees.

Kernel Version & Testing:
- These patches were developed and tested on Linux 6.13.
- Attempting to run Linux 6.14-rc2 on our Lantronix SOM resulted in a crash, making it unsuitable for validation.
- Validation was performed using a modified device tree, confirming proper regulator configuration.
- No regressions were observed on existing PMIC configurations.

Next Steps:
If there are any suggestions or required changes, please let me know. I will be happy to revise and address any concerns.

Thanks again,
James A. MacInnes
james.a.macinnes@gmail.com

James A. MacInnes (3):
regulator: qcom_usb_vbus: Update DTS binding for PMI8998 support
regulator: qcom_usb_vbus: Add support for PMI8998 VBUS
arm64: boot: dts: pmi8998.dtsi: Add VBUS regulator

.../regulator/qcom,usb-vbus-regulator.yaml | 1 +
arch/arm64/boot/dts/qcom/pmi8998.dtsi | 6 ++++
drivers/regulator/qcom_usb_vbus-regulator.c | 33 ++++++++++++++++---
3 files changed, 35 insertions(+), 5 deletions(-)

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2.43.0