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Date:   Wed, 28 Dec 2022 09:59:03 +0100
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Subject: Re: [RFC PATCH 06/14] usb: core: hcd: Introduce USB HCD APIs for
 interrupter management
Content-Language: en-US
To:     Wesley Cheng <quic_wcheng@quicinc.com>,
        Alan Stern <stern@rowland.harvard.edu>
Cc:     srinivas.kandagatla@linaro.org, mathias.nyman@intel.com,
        perex@perex.cz, broonie@kernel.org, lgirdwood@gmail.com,
        andersson@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        gregkh@linuxfoundation.org, Thinh.Nguyen@synopsys.com,
        bgoswami@quicinc.com, tiwai@suse.com, robh+dt@kernel.org,
        agross@kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-msm@vger.kernel.org, alsa-devel@alsa-project.org,
        devicetree@vger.kernel.org, linux-usb@vger.kernel.org,
        quic_jackp@quicinc.com, quic_plai@quicinc.com
References: <20221223233200.26089-1-quic_wcheng@quicinc.com>
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 <Y6ca8IKLK9g497Qv@rowland.harvard.edu>
 <e1203849-01b4-b196-36f3-76d58dd7c724@quicinc.com>
From:   Oliver Neukum <oneukum@suse.com>
In-Reply-To: <e1203849-01b4-b196-36f3-76d58dd7c724@quicinc.com>
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On 27.12.22 22:07, Wesley Cheng wrote:

> 
> Hmmm...maybe I should change the name of the API then to avoid the confusion.  Yes, usb_hcd_flush_endpoint() does ensure that URBs submitted to the EP are stopped.  However, with this offloading concept, we aren't actually submitting URBs from the main processor, so the ep->urb_list will be empty.
> 
> This means the usb_hcd_flush_endpoint() API won't actually do anything.  What we need is to ensure that we send a XHCI stop ep command to the controller.

That is a concept specific to XHCI, yet you are adding a generic
API. The namin should reflect that. usb_quiesce_endpoint() ?

	Regards
		Oliver