[PATCH v3 0/4] usb: typec: Add new driver for Parade PS8830 Type-C Retimer

Abel Vesa
2024-10-22T10:27:13Z

The Parade PS8830 is a Type-C multi-protocol retimer that is controlled
via I2C. It provides altmode and orientation handling and usually sits
between the Type-C port and the PHY.

It is currently used alongside Qualcomm Snapdragon X Elite SoCs on quite
a few laptops already.

This new driver adds support for the following 3 modes:
- DP 4lanes (pin assignments C and E)
- DP 2lanes + USB3 (pin assignment D)
- USB3

This retimer is a LTTPR (Link-Training Tunable PHY Repeater) which means
it can support link training from source to itself. This means that the
DP driver needs to be aware of the repeater presence and to handle
the link training accordingly. This is currently missing from msm dp
driver, but there is already effort going on to add it. Once done,
full external DP will be working on all X1E laptops that make use of
this retimer.

NOTE: Currently, due to both LTTPR missing support in msm DP and a
reported crash that can happen on DP unplug, the DP DT patch is not
supposed to be merged yet. That patch is only shared for testing purposes.
Once those 2 issues have been resolved, the MDSS DP 0-2 enablement patch
will be respun.

Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
---
Changes in v3:
- Reworked the schema binding by using the usb/usb-switch.yaml defined
port graph and properties. Addressed all comments from Johan and
Dmitry.
- Dropped the manual caching of the config values on regmap write in the
driver.
- Reordered the DP pin assignment states within the switch clause, as
Dmitry suggested.
- Added SVID check to not allow any altmode other than DP.
- Added DT patches (retimer for USB orientation handling and DP
enablement). Did this in order to offer a full picture of how it all
fits together.
- Split the DP enablement in DT in a separate patchset so the USB
handling can be merged separately.
- Added ps8830,boot-on to let the driver know it is supposed to skip
resetting the retimer on driver probe, as the bootloader might already
let it in a pre-configured state.
- Marked all retimer voltage regulators as boot-on since we want to
maintain the state for coldplug orientation.
- Added pinconf for all retimer0 gpios.
- Didn't pick up Konrad's T-b tags and Krzysztof's R-b tag as the rework
is quite extensive. Especially because of the ps8830,boot-on and what
it does.
- Link to v2: https://lore.kernel.org/r/20241004-x1e80100-ps8830-v2-0-5cd8008c8c40@linaro.org

Changes in v2:
- Addressed all comments from Johan and Konrad.
- Reworked the handling of the vregs so it would be more cleaner.
Dropped the usage of bulk regulators API and handled them separately.
Also discribed all regulators according to data sheet.
- Added all delays according to data sheet.
- Fixed coldplug (on boot) orientation detection.
- Didn't pick Krzysztof's R-b tag because the bindings changed w.r.t
supplies.
- Link to v1: https://lore.kernel.org/r/20240829-x1e80100-ps8830-v1-0-bcc4790b1d45@linaro.org

---
Abel Vesa (4):
dt-bindings: usb: Add Parade PS8830 Type-C retimer bindings
usb: typec: Add support for Parade PS8830 Type-C Retimer
arm64: dts: qcom: x1e80100-crd: Add Parade PS8830 related nodes
arm64: dts: qcom: x1e80100-crd: Enable external DP

.../devicetree/bindings/usb/parade,ps8830.yaml | 129 ++++++
arch/arm64/boot/dts/qcom/x1e80100-crd.dts | 472 ++++++++++++++++++++-
drivers/usb/typec/mux/Kconfig | 10 +
drivers/usb/typec/mux/Makefile | 1 +
drivers/usb/typec/mux/ps8830.c | 423 ++++++++++++++++++
5 files changed, 1029 insertions(+), 6 deletions(-)
---
base-commit: 63b3ff03d91ae8f875fe8747c781a521f78cde17
change-id: 20240521-x1e80100-ps8830-d5ccca95b557

Best regards,
--
Abel Vesa <abel.vesa@linaro.org>