Re: [PATCH] phy: allwinner: sun4i-usb: poll vbus changes on A23/A33 when driving VBUS

[Chen-Yu Tsai]

Hi Kishon,

On Fri, Feb 16, 2018 at 7:20 PM, Kishon Vijay Abraham I <kishon@xxxxxx> wrote:
>
>
> On Friday 19 January 2018 08:15 PM, Maxime Ripard wrote:
>> On Fri, Jan 19, 2018 at 05:25:41PM +0800, Chen-Yu Tsai wrote:
>>> The AXP223 PMIC, like the AXP221, does not generate VBUS change
>>> interrupts when N_VBUSEN is used to drive VBUS for the OTG port
>>> on the board.
>>>
>>> This was not noticed until recently, as most A23/A33 boards use
>>> a GPIO pin that does not support interrupts for OTG ID detection.
>>> This forces the driver to use polling. However the A33-OlinuXino
>>> uses a pin that does support interrupts, so the driver uses them.
>>> However the VBUS interrupt never fires, and the driver never gets
>>> to update the VBUS status. This results in musb timing out waiting
>>> for VBUS to rise.
>>>
>>> This was worked around for the AXP221 by resorting to polling
>>> changes in commit 91d96f06a760 ("phy-sun4i-usb: Add workaround for
>>> missing Vbus det interrupts on A31"). This patch adds the A23 and
>>> A33 to the list of SoCs that need the workaround.
>>>
>>> Fixes: fc1f45ed3043 ("phy-sun4i-usb: Add support for the usb-phys on the
>>>                    sun8i-a33 SoC")
>>> Fixes: 123dfdbcfaf5 ("phy-sun4i-usb: Add support for the usb-phys on the
>>>                    sun8i-a23 SoC")
>>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.3.x: 68dbc2ce77bb phy-sun4i-usb:
>>>              Use of_match_node to get model specific config data
>>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.3.x: 5cf700ac9d50 phy: phy-sun4i-usb:
>>>              Fix optional gpios failing probe
>>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.3.x: 04e59a0211ff phy-sun4i-usb:
>>>              Fix irq free conditions to match request conditions
>>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.3.x: 91d96f06a760 phy-sun4i-usb:
>>>              Add workaround for missing Vbus det interrupts on A31
>>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.3.x
>>> Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>
>>> ---
>>>
>>> This list might get longer if the newer AXP8xx PMICs also have this
>>> behavior. We could switch to a boolean in the per-compatible data,
>>> or just always use polling. The yet-merged R40 support will have this
>>> issue as well, as the R40 is paired with the AXP221. But for now,
>>> I'd like to have something that is easier to backport to stable, so
>>> we can at least fix this for the A23 and A33.
>>>
>>> Also, checkpatch.pl doesn't like the stable kernel prerequisite lines.
>>
>> Acked-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
>
> merged, thanks!

I see you moved this patch from your fixes branch to your -next branch.
Is there any problem with the patch? Merge issues?


Thanks
ChenYu