Re: [PATCH 0/7] usb: typec: ucsi: fix several issues manifesting on Qualcomm platforms

[Johan Hovold <johan@kernel.org>]

On Mon, Mar 25, 2024 at 10:56:21PM +0200, Dmitry Baryshkov wrote:
> On Fri, 22 Mar 2024 at 14:16, Johan Hovold <johan@kernel.org> wrote:

> > I just gave this series a quick spin on my X13s and it seems there are
> > still some issues that needs to be resolved before merging at least the
> > final patch in this series:
> >
> > [    7.786167] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: unknown error 0
> > [    7.786445] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: UCSI_GET_PDOS failed (-5)
> > [    7.883493] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: unknown error 0
> > [    7.883614] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: UCSI_GET_PDOS failed (-5)
> > [    7.905194] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: unknown error 0
> > [    7.905295] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: UCSI_GET_PDOS failed (-5)
> > [    7.913340] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: unknown error 0
> > [    7.913409] ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: UCSI_GET_PDOS failed (-5)
> 
> I have traced what is causing these messages. During UCSI startup the
> ucsi_register_port() function queries for PDOs associated with the
> on-board USB-C port. This is allowed by the spec. Qualcomm firmware
> detects that there is no PD-device connected and instead of returning
> corresponding set of PDOs returns Eerror Indicator set to 1b but then
> it returns zero error status in response to GET_ERROR_STATUS, causing
> "unknown error 0" code. I have checked the PPM, it doesn't even have
> the code to set the error status properly in this case (not to mention
> that asking for device's PDOs should not be an error, unless the
> command is inappropriate for the target.
> 
> Thus said, I think the driver is behaving correctly. Granted that
> these messages are harmless, we can ignore them for now. I'll later
> check if we can update PD information for the device's ports when PD
> device is attached. I have verified that once the PD device is
> attached, corresponding GET_PDOS command returns correct set of PD
> objects. Ccurrently the driver registers usb_power_delivery devices,
> but with neither source nor sink set of capabilities.
> 
> An alternative option is to drop patches 4 and 5, keeping
> 'NO_PARTNER_PDOS' quirk equivalent to 'don't send GET_PDOS at all'.
> However I'd like to abstain from this option, since it doesn't allow
> us to check PD capabilities of the attached device.
> 
> Heikki, Johan, WDYT?

Whatever you do, you need to suppress those errors above before enabling
anything more on sc8280xp (e.g. even if it means adding a quirk to the
driver).

Johan