Re: [PATCH v4 6/7] phy: exynos5-usbdrd: subscribe to orientation notifier if required

[Krzysztof Kozlowski <krzk@kernel.org>]

On 14/02/2025 20:30, Marek Szyprowski wrote:
> On 06.12.2024 17:31, André Draszik wrote:
>> gs101's SS phy needs to be configured differently based on the
>> connector orientation, as the SS link can only be established if the
>> mux is configured correctly.
>>
>> The code to handle programming of the mux is in place already, this commit
>> now adds the missing pieces to subscribe to the Type-C orientation
>> switch event.
>>
>> Note that for this all to work we rely on the USB controller
>> re-initialising us. It should invoke our .exit() upon cable unplug, and
>> during cable plug we'll receive the orientation event after which we
>> expect our .init() to be called.
>>
>> Above reinitialisation happens if the DWC3 controller can enter runtime
>> suspend automatically. For the DWC3 driver, this is an opt-in:
>>      echo auto > /sys/devices/.../11110000.usb/power/control
>> Once done, things work as long as the UDC is not bound as otherwise it
>> stays busy because it doesn't cancel / stop outstanding TRBs. For now
>> we have to manually unbind the UDC in that case:
>>       echo "" > sys/kernel/config/usb_gadget/.../UDC
>>
>> Note that if the orientation-switch property is missing from the DT,
>> the code will behave as before this commit (meaning for gs101 it will
>> work in SS mode in one orientation only). Other platforms are not
>> affected either way.
>>
>> Signed-off-by: André Draszik <andre.draszik@linaro.org>
>>
>> ---
>> v3:
>> * drop init to -1 of phy_drd->orientation (Vinod)
>> * avoid #ifdef and switch to normal conditional IS_ENABLED() for
>>    CONFIG_TYPEC
>>
>> v2:
>> * move #include typec_mux.h from parent patch into this one (Peter)
>> ---
>>   drivers/phy/samsung/Kconfig              |  1 +
>>   drivers/phy/samsung/phy-exynos5-usbdrd.c | 56 ++++++++++++++++++++++++++++++++
>>   2 files changed, 57 insertions(+)
>>
>> diff --git a/drivers/phy/samsung/Kconfig b/drivers/phy/samsung/Kconfig
>> index f10afa3d7ff5..fc7bd1088576 100644
>> --- a/drivers/phy/samsung/Kconfig
>> +++ b/drivers/phy/samsung/Kconfig
>> @@ -80,6 +80,7 @@ config PHY_EXYNOS5_USBDRD
>>   	tristate "Exynos5 SoC series USB DRD PHY driver"
>>   	depends on (ARCH_EXYNOS && OF) || COMPILE_TEST
>>   	depends on HAS_IOMEM
>> +	depends on TYPEC || (TYPEC=n && COMPILE_TEST)
>>   	depends on USB_DWC3_EXYNOS
>>   	select GENERIC_PHY
>>   	select MFD_SYSCON


So that explains why on recent next some of my boards don't boot. I was
about to dig over the weekend.

> 
> I've just noticed that the above disables Exynos DRD PHY driver in the 
> default exynos_defconfig for arm 32bit. Enabling CONFIG_TYPEC is 
> exynos_defconfig probably is the easiest way to fix this. I will send a 
> patch then.

No, it's just wrong. Nothing here depends on typec and ARMv7 does not
have Typec.

Best regards,
Krzysztof