Re: [PATCH v3 0/4] Restore ULPI USB on Tegra20

From: Thierry Reding
Date: Fri May 18 2018 - 05:41:25 EST


On Tue, May 08, 2018 at 07:26:02PM +0300, Dmitry Osipenko wrote:
> Hello,
>
> This series of patches fixes ULPI USB on Tegra20. The original problem
> was reported by Marcel Ziswiler, he found that "ulpi-link" clock was
> incorrectly set to CDEV2 instead of PLL_P_OUT4. Marcel made a patch
> that changed the "ulpi-link" clock to PLL_P_OUT4 and that fixed issue
> with the USB for the devices that have CDEV2 being enabled by bootloader.
> The patch got into the kernel and later Marc Dietrich found that USB
> stopped working on the "paz00" Tegra20 board. After a bit of discussion
> was revealed that PLL_P_OUT4 is the parent clock of the CDEV2 and clock
> driver was setting CDEV2's parent incorrectly. The parent clock is actually
> determined by the pinmuxing config of CDEV2 pingroup. This patchset fixes
> the parent of CDEV2 clock by making Tegra's pinctrl driver a clock provider,
> providing CDEV1/2 clock muxes (thanks to Peter De Schrijver for the
> suggestion), and then setting these clock muxes as parents for the CDEV1/2
> clocks. In the end Marcel's CDEV2->PLL_P_OUT4 change is reverted since CDEV2
> (aka MCLK2) is the actual clock source for "ulpi-link".
>
> Changelog:
>
> v3:
> - Use clk DT ID's instead of comparing clk names and make
> custom of_src_onecell_get specific to Tegra20 clk provider
> in the "Add quirk for getting CDEV1/2 clocks on Tegra20" patch
> as was suggested by Peter De Schrijver for v2.
>
> v2:
> - Added new patch "Add quirk for getting CDEV1/2 clocks", assuring
> that clk user won't get CDEV1/2 clocks until parent clk muxes
> are available, i.e. resolves potential issue with CDEV-user driver
> vs pinctrl driver probe order.
>
> - Factored out "pinctrl" patch from the patchset as was requested by
> Linus Walleij.
>
> - Addressed v1 review comments: fixed swapped DEV1/2 clk div bits,
> made DEV1/2 divs read-only, etc minor changes.
>
> Dmitry Osipenko (4):
> clk: tegra20: Add DEV1/DEV2 OSC dividers
> clk: tegra20: Correct parents of CDEV1/2 clocks
> clk: tegra: Add quirk for getting CDEV1/2 clocks on Tegra20
> ARM: dts: tegra20: Revert "Fix ULPI regression on Tegra20"

Patches 1-3 applied, thanks.

Thierry

Attachment: signature.asc
Description: PGP signature