Re: [added to the 4.1 stable tree] usb: host: xhci-rcar: Use ARCH_RENESAS

Re: [added to the 4.1 stable tree] usb: host: xhci-rcar: Use ARCH_RENESAS

[Simon Horman]

Hi,

I do not believe this patch is suitable for v4.1 stable.

ARCH_RENESAS is not otherwise present there and thus the driver in question
will stop being compiled where it was previously compiled.

Moreover, the transition to ARCH_RENESAS is (so far) being handled in such
a way that there have not been any regressions that would necessitate a
backport to -stable.

On Fri, Jun 03, 2016 at 05:36:01PM -0400, Sasha Levin wrote:
> From: Simon Horman <horms+renesas@verge.net.au>
> 
> This patch has been added to the 4.1 stable tree. If you have any
> objections, please let us know.
> 
> ===============
> 
> [ Upstream commit 6edd87f589cf1cd4c93ee07b8f8c72a5af427b10 ]
> 
> Make use of ARCH_RENESAS in place of ARCH_SHMOBILE.
> 
> This is part of an ongoing process to migrate from ARCH_SHMOBILE to
> ARCH_RENESAS the motivation for which being that RENESAS seems to be a more
> appropriate name than SHMOBILE for the majority of Renesas ARM based SoCs.
> 
> Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
> ---
>  drivers/usb/host/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
> index 197a6a3..2379773 100644
> --- a/drivers/usb/host/Kconfig
> +++ b/drivers/usb/host/Kconfig
> @@ -45,7 +45,7 @@ config USB_XHCI_MVEBU
>  config USB_XHCI_RCAR
>  	tristate "xHCI support for Renesas R-Car SoCs"
>  	select USB_XHCI_PLATFORM
> -	depends on ARCH_SHMOBILE || COMPILE_TEST
> +	depends on ARCH_RENESAS || COMPILE_TEST
>  	---help---
>  	  Say 'Y' to enable the support for the xHCI host controller
>  	  found in Renesas R-Car ARM SoCs.
> -- 
> 2.5.0
> 

Re: [added to the 4.1 stable tree] usb: host: xhci-rcar: Use ARCH_RENESAS

[Sasha Levin]

On 06/03/2016 08:47 PM, Simon Horman wrote:
> Hi,
> 
> I do not believe this patch is suitable for v4.1 stable.
> 
> ARCH_RENESAS is not otherwise present there and thus the driver in question
> will stop being compiled where it was previously compiled.
> 
> Moreover, the transition to ARCH_RENESAS is (so far) being handled in such
> a way that there have not been any regressions that would necessitate a
> backport to -stable.

Hey Simon,

I've picked this commit because of what I saw in f879fc32a
("usb: host: xhci-rcar: Avoid long wait in xhci_reset()").

>From my understanding of that change, we added a dependency on ARCH_RENESAS
for USB_XHCI_PLATFORM, but since USB_XHCI_RCAR depended on ARCH_SHMOBILE that
would cause silly errors for kconfig and would probably confuse users.

Rather than changing it to a ARCH_SHMOBILE dependency, I've preferred
to pull in f879fc32a to keep the stable tree more aligned with upstream
and possibly prevent any future backporting errors for new commits that
add ARCH_RENESAS dependencies.

If you don't agree with that approach I can change that to a ARCH_SHMOBILE
dependency and remove this commit, or take any other approach you think
is better?


Thanks,
Sasha

Re: [added to the 4.1 stable tree] usb: host: xhci-rcar: Use ARCH_RENESAS

[Simon Horman]

[Cc Shimoda-san]

On Fri, Jun 03, 2016 at 09:14:17PM -0400, Sasha Levin wrote:
> On 06/03/2016 08:47 PM, Simon Horman wrote:
> > Hi,
> > 
> > I do not believe this patch is suitable for v4.1 stable.
> > 
> > ARCH_RENESAS is not otherwise present there and thus the driver in question
> > will stop being compiled where it was previously compiled.
> > 
> > Moreover, the transition to ARCH_RENESAS is (so far) being handled in such
> > a way that there have not been any regressions that would necessitate a
> > backport to -stable.
> 
> Hey Simon,
> 
> I've picked this commit because of what I saw in f879fc32a
> ("usb: host: xhci-rcar: Avoid long wait in xhci_reset()").
> 
> >From my understanding of that change, we added a dependency on ARCH_RENESAS
> for USB_XHCI_PLATFORM, but since USB_XHCI_RCAR depended on ARCH_SHMOBILE that
> would cause silly errors for kconfig and would probably confuse users.
> 
> Rather than changing it to a ARCH_SHMOBILE dependency, I've preferred
> to pull in f879fc32a to keep the stable tree more aligned with upstream
> and possibly prevent any future backporting errors for new commits that
> add ARCH_RENESAS dependencies.
> 
> If you don't agree with that approach I can change that to a ARCH_SHMOBILE
> dependency and remove this commit, or take any other approach you think
> is better?

Thanks, this does seem to be a bit of a mess. Sorry about that.

My feeling is that it would be better to change f879fc32a to use
ARCH_SHMOBILE as ARCH_RENESAS does not exist in v4.1.

One slight risk in this approach is that ARCH_SHMOBILE covers some (older)
SH SoCs as well as (newer) ARM and arm64 based SoCs (Renesas arm64 based
SoCs are not present in v4.1) whereas ARCH_RENESAS (in kernels that it
exists) only covers ARM and arm64 based SoCs. So the coverage of
ARCH_SHMOBILE is broader. But I don't think that should be a problem as
that is already the dependency being used in v4.1.

A quick compile test using ecovec24_defconfig + USB_XHCI_HCD +
USB_XHCI_RCAR indicates that the driver compiles on that platform.