Re: [PATCH 0/3] (Qualcomm) UFS device reset support

From: Bjorn Andersson
Date: Wed Jun 05 2019 - 02:05:09 EST


On Tue 04 Jun 22:50 PDT 2019, Avri Altman wrote:

> Hi,
>
> >
> > On Tue, Jun 4, 2019 at 12:22 AM Bjorn Andersson
> > <bjorn.andersson@xxxxxxxxxx> wrote:
> > >
> > > This series exposes the ufs_reset line as a gpio, adds support for ufshcd to
> > > acquire and toggle this and then adds this to SDM845 MTP.
> > >
> > > Bjorn Andersson (3):
> > > pinctrl: qcom: sdm845: Expose ufs_reset as gpio
> > > scsi: ufs: Allow resetting the UFS device
> > > arm64: dts: qcom: sdm845-mtp: Specify UFS device-reset GPIO
> >
> > Adding similar change as in sdm845-mtp to the not yet upstream
> > blueline dts, I validated this allows my micron UFS pixel3 to boot.
> >
> > Tested-by: John Stultz <john.stultz@xxxxxxxxxx>
> Maybe ufs_hba_variant_ops would be the proper place to add this?
>

Are you saying that these memories only need a reset when they are
paired with the Qualcomm host controller?

The way it's implemented it here is that the device-reset GPIO is
optional and only if you specify it we'll toggle the reset. So if your
board design has a UFS memory that requires a reset pulse during
initialization you specify this, regardless of which vendor your SoC
comes from.

Regards,
Bjorn