Re: [PATCH v2 2/3] scsi: ufs: Allow resetting the UFS device

From: Rob Herring
Date: Mon Jul 08 2019 - 21:48:37 EST


On Wed, Jun 05, 2019 at 06:02:48PM -0700, Bjorn Andersson wrote:
> Acquire the device-reset GPIO and toggle this to reset the UFS device
> during initialization and host reset.
>
> Based on downstream support implemented by Subhash Jadavani
> <subhashj@xxxxxxxxxxxxxx>.
>
> Tested-by: John Stultz <john.stultz@xxxxxxxxxx>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> ---
>
> Changes since v1:
> - Added gpio to DT binding document
> - Fixed spelling of UFS
>
> .../devicetree/bindings/ufs/ufshcd-pltfrm.txt | 2 +
> drivers/scsi/ufs/ufshcd.c | 44 +++++++++++++++++++
> drivers/scsi/ufs/ufshcd.h | 4 ++
> 3 files changed, 50 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
> index a74720486ee2..d562d8b4919c 100644
> --- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
> +++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt
> @@ -54,6 +54,8 @@ Optional properties:
> PHY reset from the UFS controller.
> - resets : reset node register
> - reset-names : describe reset node register, the "rst" corresponds to reset the whole UFS IP.
> +- device-reset-gpios : A phandle and gpio specifier denoting the GPIO connected
> + to the RESET pin of the UFS memory device.

A sign we should have a child node for the device...

Doesn't using 'reset-gpios' work as I doubt one would have a GPIO reset
for the host controller.

Rob