From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Mon, 13 Apr 2015 01:19:18 +0200 Subject: [U-Boot] [PATCH] usb: dwc2: retry NAK'd interrupt transfers In-Reply-To: <1428810722-20673-1-git-send-email-swarren@wwwdotorg.org> References: <1428810722-20673-1-git-send-email-swarren@wwwdotorg.org> Message-ID: <201504130119.18388.marex@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Sunday, April 12, 2015 at 05:52:02 AM, Stephen Warren wrote: > IIUC, interrupt transfers are NAK'd by devices until they wish to trigger > an interrupt, and e.g. EHCI controllers retry these in HW until they are > ACK'd. However, DWC2 doesn't seem to retry, so we need to do this in SW. > In practice, I've seen DWC2_HCINT_FRMOVRUN happen too. I'm not quite sure > what this error implies; perhaps it's related to how near the end of a > USB frame we're at when the interrupt transfer is initiated? Anyway, > retrying this temporary error seems to be necessary too. > > With all these commits applied, both my USB keyboards (one LS Lenovo and > one FS Dell) work correctly when there is no USB hub between the SoC and > the keyboard; We still need split transactions to be implemented for hubs > to work. > > Signed-off-by: Stephen Warren Applied to u-boot-usb/topic/dwc2 , thanks! Best regards, Marek Vasut