Subject: Re: [PATCH 00/13] usb: dwc3: meson: add OTG support for GXL/GXM

From: Felipe Balbi <[email-masked]>
Date: Thu, 14 May 2020 15:59:52 +0300

Neil Armstrong <[email-masked]> writes:

> Hi,
>
> On 14/05/2020 12:23, Felipe Balbi wrote:
>> Felipe Balbi <[email-masked]> writes:
>> 
>>> Neil Armstrong <[email-masked]> writes:
>>>
>>>> The USB support was initialy done with a set of PHYs and dwc3-of-simple
>>>> because the architecture of the USB complex was not understood correctly
>>>> at the time (and proper documentation was missing...).
>>>>
>>>> But with the G12A family, the USB complex was correctly understood and
>>>> implemented correctly.
>>>> But seems the G12A architecture was derived for the GXL USB architecture,
>>>> with minor differences and looks we can share most of the USB DWC3 glue
>>>> driver.
>>>>
>>>> This patchset refactors and adds callbacks to handle the architecture
>>>> difference while keeping the main code shared.
>>>>
>>>> The main difference is that on GXL/GXM the USB2 PHY control registers
>>>> are mixed with the PHY registers (we already handle correctly), and
>>>> the GLUE registers are allmost (99%) the same as G12A.
>>>>
>>>> But, the GXL/GXM HW is buggy, here are the quirks :
>>>> - for the DWC2 controller to reset correctly, the GLUE mux must be switched
>>>>   to peripheral when the DWC2 controlle probes. For now it's handled by simply
>>>>   switching to device when probing the subnodes, but it may be not enough
>>>> - when manually switching from Host to Device when the USB port is not
>>>>   populated (should not happen with proper Micro-USB/USB-C OTG switch), it
>>>>   makes the DWC3 to crash. The only way to avoid that is to use the Host
>>>>   Disconnect bit to disconnect the DWC3 controller from the port, but we can't
>>>>   recover the Host functionnality unless resetting the DWC3 controller.
>>>>   This bit is set when only manual switch is done, and a warning is printed
>>>>   on manual switching.
>>>>
>>>> The patches 1-8 should be applied first, then either waiting the next release
>>>> or if the usb maintainer can provide us a stable tag, we can use it to merge
>>>> the DT and bindings.
>>>
>>> it's unclear to me if this series is ready to be merged. Can someone
>>> confirm? If it is, can you resend with all reviewed by tags in place?
>> 
>> Are we getting a v2 for this?
>> 
>
> Yes, even a v3 with reviews on all patches:
> http://lkml.kernel.org/r/[email-masked]

In that case, can you check that I have applied everything correctly in
testing/next?

cheers

-- 
balbi
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