From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Krivoschekov Subject: Re: Patch [2/2] DaVinci CPPI TX DMA tasklet Date: Thu, 21 Aug 2008 19:09:26 +0400 Message-ID: <48AD8526.8080206@gmail.com> References: <1219327122-28334-1-git-send-email-swami.iyer@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1219327122-28334-1-git-send-email-swami.iyer-l0cyMroinI0@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Swaminathan S Cc: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, felipe.balbi-xNZwKgViW5gAvxtiuMwx3w@public.gmane.org List-Id: linux-omap@vger.kernel.org Hi Swami, Swaminathan S wrote: > Signed-off-by: Swaminathan S > > This patch implements a tasklet to poll for TX Endpoint FIFO > empty status before completing a transfer. This is required > in the context of DaVinci CPPI DMA Tx transfers. CPPI > DMA engine generates completion interrupt before the data > actually moves out of TX FIFO I guess the DMA interrupt is generated after the data have been moved from a s/w buffer to TX FIFO. > and the driver needs to save the > Data toggle after ensuring that the FIFO is empty. why don't rely on an endpoint interrupt which is generated after a USB transaction is complete? Thanks, Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html