Re: [PATCH 0/3] Implement role-switch notifications from dwc3-drd to dwc3-qcom

[Felipe Balbi <balbi@kernel.org>]

Hi,

Bjorn Andersson <bjorn.andersson@linaro.org> writes:
> On Wed 07 Jul 20:06 PDT 2021, Peter Chen wrote:
>
>> On 21-07-07 14:03:19, Bjorn Andersson wrote:
>> > On Tue 06 Jul 20:57 CDT 2021, Peter Chen wrote:
>> > 
>> > Allow me to reorder your two questions:
>> > 
>> > > And why using a notifier need to concern core's deferral probe?
>> > 
>> > The problem at hand calls for the core for somehow invoking
>> > dwc3_qcom_vbus_overrride_enable() with a pointer to dwc3_qcom passed.
>> > 
>> > This means that dwc3-qcom somehow needs to inform the dwc3-core about
>> > this (and stash the pointer). And this can't be done until dwc3-core
>> > actually exist, which it won't until dwc3_probe() has completed
>> > successfully (or in particular allocated struct dwc).
>> 
>> Maybe you misunderstood the notifier I meant previous, my pointer was
>> calling glue layer API directly.
>> 
>> Role switch is from dwc3-core, when it occurs, it means structure dwc3 has
>> allocated successfully, you could call glue layer notifier at function
>> dwc3_usb_role_switch_set directly.
>> Some references of my idea [1] [2]
>> 
>> [1] Function ci_hdrc_msm_notify_event at ci_hdrc_msm_notify_event
>> [2] https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/usb/dwc3/core.c?h=lf-5.10.y#n205
>> 
>
> Hi Peter, I took a proper look at this again, hoping to find a way to
> pass a callback pointer from dwc3-qcom to the dwc3 core, that can be
> called from __dwc3_set_mode() to inform the Qualcomm glue about mode
> changes.

I would rather keep the strict separation between glue and core.

-- 
balbi