Re: [PATCH v7 2/4] usb: dwc3: qcom: Add interconnect support in dwc3 driver

From: "Sandeep Maheswaram (Temp)" <sanm@codeaurora.org>
To: Bjorn Andersson <bjorn.andersson@linaro.org>,
	Felipe Balbi <balbi@kernel.org>
Cc: Georgi Djakov <georgi.djakov@linaro.org>,
	Matthias Kaehlcke <mka@chromium.org>,
	Andy Gross <agross@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Stephen Boyd <swboyd@chromium.org>,
	Doug Anderson <dianders@chromium.org>,
	linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	Manu Gautam <mgautam@codeaurora.org>,
	Chandana Kishori Chiluveru <cchiluve@codeaurora.org>,
	Viresh Kumar <viresh.kumar@linaro.org>
Subject: Re: [PATCH v7 2/4] usb: dwc3: qcom: Add interconnect support in dwc3 driver
Date: Tue, 26 May 2020 16:34:06 +0530	[thread overview]
Message-ID: <b20775ba-7870-b0ca-7c65-d72a08fdacb2@codeaurora.org> (raw)
In-Reply-To: <20200518183512.GE2165@builder.lan>

Hi Felipe,

Please let me know how to go forward with this patch

Regards

Sandeep

On 5/19/2020 12:05 AM, Bjorn Andersson wrote:
> On Thu 14 May 23:29 PDT 2020, Felipe Balbi wrote:
>
>> Hi,
>>
>> Georgi Djakov <georgi.djakov@linaro.org> writes:
>>>>>>>> Sandeep Maheswaram <sanm@codeaurora.org> writes:
>>>>>>>>> +static int dwc3_qcom_interconnect_init(struct dwc3_qcom *qcom)
>>>>>>>>> +{
>>>>>>>>> +	struct device *dev = qcom->dev;
>>>>>>>>> +	int ret;
>>>>>>>>> +
>>>>>>>>> +	if (!device_is_bound(&qcom->dwc3->dev))
>>>>>>>>> +		return -EPROBE_DEFER;
>>>>>>>> this breaks allmodconfig. I'm dropping this series from my queue for
>>>>>>>> this merge window.
>>>>>>> Sorry, I meant this patch ;-)
>>>>>> I guess that's due to INTERCONNECT being a module. There is currently a
>>>>> I believe it's because of this:
>>>>> ERROR: modpost: "device_is_bound" [drivers/usb/dwc3/dwc3-qcom.ko] undefined!
>>>>>
>>>>>> discussion about this  with Viresh and Georgi in response to another
>>>>>> automated build failure. Viresh suggests changing CONFIG_INTERCONNECT
>>>>>> from tristate to bool, which seems sensible to me given that interconnect
>>>>>> is a core subsystem.
>>>>> The problem you are talking about would arise when INTERCONNECT=m and
>>>>> USB_DWC3_QCOM=y and it definitely exists here and could be triggered with
>>>>> randconfig build. So i suggest to squash also the diff below.
>>>>>
>>>>> Thanks,
>>>>> Georgi
>>>>>
>>>>> ---8<---
>>>>> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
>>>>> index 206caa0ea1c6..6661788b1a76 100644
>>>>> --- a/drivers/usb/dwc3/Kconfig
>>>>> +++ b/drivers/usb/dwc3/Kconfig
>>>>> @@ -129,6 +129,7 @@ config USB_DWC3_QCOM
>>>>>   	tristate "Qualcomm Platform"
>>>>>   	depends on ARCH_QCOM || COMPILE_TEST
>>>>>   	depends on EXTCON || !EXTCON
>>>>> +	depends on INTERCONNECT || !INTERCONNECT
>>>> I would prefer to see a patch adding EXPORT_SYMBOL_GPL() to device_is_bound()
>>> Agree, but just to clarify, that these are two separate issues that need to
>>> be fixed. The device_is_bound() is the first one and USB_DWC3_QCOM=y combined
>>> with INTERCONNECT=m is the second one.
>> If INTERCONNECT=m, QCOM3 shouldn't be y. I think the following is
>> enough:
>>
>> 	depends on INTERCONNECT=y || INTERCONNECT=USB_DWC3_QCOM
>>
> This misses the case where INTERCONNECT=n and USB_DWC3_QCOM=[ym] which
> I don't see a reason for breaking.
>
> But if only INTERCONNECT where a bool, then we don't need to specify a
> depends on, because it will either be there, or the stubs will.
> We've come to this conclusion in a lot of different frameworks and I
> don't see why we should do this differently with INTERCONNECT.
>
> Regards,
> Bjorn

-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation