Re: [PATCH v6 2/4] usb: dwc3: qcom: Add interconnect support in dwc3 driver

From: "Sandeep Maheswaram (Temp)" <sanm@codeaurora.org>
To: Felipe Balbi <balbi@kernel.org>, Matthias Kaehlcke <mka@chromium.org>
Cc: Andy Gross <agross@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.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>
Subject: Re: [PATCH v6 2/4] usb: dwc3: qcom: Add interconnect support in dwc3 driver
Date: Tue, 31 Mar 2020 10:45:19 +0530	[thread overview]
Message-ID: <ec7e921a-45fe-c178-cc04-2a04dd4a75f5@codeaurora.org> (raw)
In-Reply-To: <87zhbx1q6q.fsf@kernel.org>

Hi,

On 3/31/2020 3:05 AM, Felipe Balbi wrote:
> Hi,
>
> Matthias Kaehlcke <mka@chromium.org> writes:
>>> Matthias Kaehlcke <mka@chromium.org> writes:
>>>>> Add interconnect support in dwc3-qcom driver to vote for bus
>>>>> bandwidth.
>>>>>
>>>>> This requires for two different paths - from USB master to
>>>>> DDR slave. The other is from APPS master to USB slave.
>>>>>
>>>>> Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
>>>>> Signed-off-by: Chandana Kishori Chiluveru <cchiluve@codeaurora.org>
>>>>> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
>>>>> ---
>>>>>   drivers/usb/dwc3/dwc3-qcom.c | 128 ++++++++++++++++++++++++++++++++++++++++++-
>>>>>   1 file changed, 126 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
>>>>> index 1dfd024..7e85fe6 100644
>>>>> --- a/drivers/usb/dwc3/dwc3-qcom.c
>>>>> +++ b/drivers/usb/dwc3/dwc3-qcom.c
>>>>>
>>>>> ...
>>>>>
>>>>> +/* To disable an interconnect, we just set its bandwidth to 0 */
>>>>> +static int dwc3_qcom_interconnect_disable(struct dwc3_qcom *qcom)
>>>>> +{
>>>>> +	int ret;
>>>>> +
>>>>> +	ret = icc_set_bw(qcom->usb_ddr_icc_path, 0, 0);
>>>>> +	if (ret)
>>>>> +		return ret;
>>>>> +
>>>>> +	ret = icc_set_bw(qcom->apps_usb_icc_path, 0, 0);
>>>>> +	if (ret)
>>>>> +		goto err_reenable_memory_path;
>>>>> +
>>>>> +	return 0;
>>>>> +
>>>>> +	/* Re-enable things in the event of an error */
>>>>> +err_reenable_memory_path:
>>>>> +	ret = dwc3_qcom_interconnect_enable(qcom);
>>>> This overwrites the error that led to the execution of this code path.
>>>> The function should return original error, not the result of the
>>>> _interconnect_enable() call.
>>>>
>>>> I saw Felipe queued the patch for v5.8. I think the main options to fix this
>>>> are:
>>>>
>>>> - a v6 of this patch to replace v5 in Felipe's tree (which IIUC will be rebased
>>>>    anyway once there is a v5.7-rc)
>>>> - send the fix as a separate patch
>>>> - Felipe amends the patch in his tree
>>>>
>>>> Felipe, what would work best for you?
>>> Let's go for a v6, which commits should I drop? I can't find anything
>>> related to $subject in my queue:
>>>
>>> $ git --no-pager log --oneline HEAD ^linus/master -- drivers/usb/dwc3/dwc3-qcom.c
>>> 201c26c08db4 usb: dwc3: qcom: Replace <linux/clk-provider.h> by <linux/of_clk.h>
>> I thought I saw a "queued for v5.8" message from you, but can't find that back.
>> I guess I saw the "queued" message for the "Add USB DWC3 support for SC7180"
>> series and thought it was for this one. Sorry for the confusion.
> no worries :-)
>
Should I remove the ret from below line and send a new version?
+	ret = dwc3_qcom_interconnect_enable(qcom);

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