Re: [PATCH AUTOSEL 5.10 1/7] phy: sun4i-usb: Add support for the H616 USB PHY

[Sasha Levin]

On Tue, Dec 27, 2022 at 10:23:30PM +0000, Andre Przywara wrote:
> On Tue, 27 Dec 2022 15:58:16 -0600
> Samuel Holland <samuel@xxxxxxxxxxxx> wrote:
>
> > Hi Sasha,
> >
> > On 12/27/22 14:35, Sasha Levin wrote:
> > > From: Andre Przywara <andre.przywara@xxxxxxx>
> > >
> > > [ Upstream commit 0f607406525d25019dd9c498bcc0b42734fc59d5 ]
> > >
> > > The USB PHY used in the Allwinner H616 SoC inherits some traits from its
> > > various predecessors: it has four full PHYs like the H3, needs some
> > > extra bits to be set like the H6, and puts SIDDQ on a different bit like
> > > the A100. Plus it needs this weird PHY2 quirk.
> > >
> > > Name all those properties in a new config struct and assign a new
> > > compatible name to it.
> > >
> > > Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx>
> > > Reviewed-by: Samuel Holland <samuel@xxxxxxxxxxxx>
> > > Link: https://lore.kernel.org/r/20221031111358.3387297-5-andre.przywara@xxxxxxx
> > > Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
> > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> > > ---
> > >  drivers/phy/allwinner/phy-sun4i-usb.c | 12 ++++++++++++
> > >  1 file changed, 12 insertions(+)
> > >
> > > diff --git a/drivers/phy/allwinner/phy-sun4i-usb.c b/drivers/phy/allwinner/phy-sun4i-usb.c
> > > index 651d5e2a25ce..230987e55ece 100644
> > > --- a/drivers/phy/allwinner/phy-sun4i-usb.c
> > > +++ b/drivers/phy/allwinner/phy-sun4i-usb.c
> > > @@ -974,6 +974,17 @@ static const struct sun4i_usb_phy_cfg sun50i_h6_cfg = {
> > >  	.missing_phys = BIT(1) | BIT(2),
> > >  };
> > >
> > > +static const struct sun4i_usb_phy_cfg sun50i_h616_cfg = {
> > > +	.num_phys = 4,
> > > +	.type = sun50i_h6_phy,
> > > +	.disc_thresh = 3,
> > > +	.phyctl_offset = REG_PHYCTL_A33,
> > > +	.dedicated_clocks = true,
> > > +	.phy0_dual_route = true,
> > > +	.hci_phy_ctl_clear = PHY_CTL_SIDDQ,
> > > +	.needs_phy2_siddq = true,
> >
> > This will fail to compile without b45c6d80325b ("phy: sun4i-usb:
> > Introduce port2 SIDDQ quirk"). However, like Andre mentioned in
> > reference to the devicetree updates[1], we were not expecting any of
> > these patches to be backported. Since you already dropped the DT
> > portion, there is no need to bother with these two patches either.
>
> Well, definitely not for 5.4 and 5.10, since the essential pinctrl and
> clock patches for the H616 were only added in 5.12, so there is no
> point in having USB support.
>
> I don't know how useful it is for 6.0, but having both patches in 6.1
> would make some sense, since it's an LTS kernel. The H616 SoC became
> usable in 6.0, with the USB patches being delayed back then. And it's
> only those two that are missing from enabling USB support, IIRC.
> The DT part is not really relevant, since you can always use U-Boot's
> DT (recommended) or the DT from any newer kernel.
>
> So from an user's perspective, it would be very helpful to just have:
> - [PATCH AUTOSEL 6.1 12/28]
> - [PATCH AUTOSEL 6.1 13/28]
> Personally I would support this, since it makes all H616 based devices
> much more usable with next year's distribution kernels.
>
> I don't know if this fulfils the stable kernel rules, though, since
> strictly speaking they don't fix anything, but add (USB) support to a
> new SoC. Then again they are little risk, since most of the code is
> guarded by H616 filters, so wouldn't be used by other SoCs.

Quirks and new device ids are accepted in the stable trees. I'll leave
those two patches on 6.1. Thanks!

--
Thanks,
Sasha