From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Date: Tue, 15 Dec 2015 19:45:48 -0700 Subject: [U-Boot] [PATCH] usb: kbd: don't use int xfers when polling via ctrl xfers In-Reply-To: <201512160142.50992.marex@denx.de> References: <1447446849-10438-1-git-send-email-swarren@wwwdotorg.org> <201511140216.46768.marex@denx.de> <5670A3BB.10909@wwwdotorg.org> <201512160142.50992.marex@denx.de> Message-ID: <5670D05C.8000309@wwwdotorg.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 12/15/2015 05:42 PM, Marek Vasut wrote: > On Wednesday, December 16, 2015 at 12:35:23 AM, Stephen Warren wrote: >> On 11/13/2015 06:16 PM, Marek Vasut wrote: >>> On Friday, November 13, 2015 at 09:34:09 PM, Stephen Warren wrote: >>>> From: Stephen Warren >>>> >>>> When CONFIG_SYS_USB_EVENT_POLL_VIA_CONTROL_EP is enabled, use a >>>> GET_REPORT control transfer to retrieve the initial state of the >>>> keyboard. This matches the technique used to poll the keyboard state. >>>> This is useful since it eliminates the remaining use of interrupt >>>> transfers from the USB keyboard driver, which allows it to work with >>>> USB HCD that don't support interrupt transfers. >>>> >>>> Cc: Hans de Goede >>>> Signed-off-by: Stephen Warren >>>> --- >>>> Are there any disadvantages to using control transfers over interrupt >>>> transfers? I'm not aware of any, but I assume there must be a reason >>>> that U-Boot typically uses interrupt transfers. >>> >>> I initially implemented the control EP polling because I had a keyboard >>> which had issues with interrupt transfers. >>> >>> Reviewed-by: Marek Vasut >> >> Did you intend someone else to apply this? > > Is the discussion concluded already? I was under the impression that there > was no general agreement. > > Otherwise I can pick this of course. The last comments in the thread were: Hans de Goede wrote: > Stephen Warren wrote: >> However, I think that fixing the existing "use control transfers" support >> so that it exclusively uses control transfers is still reasonable? > > Ack, as long as we have it, we should fix it. I do believe we should get rid > of it in the long run though.