From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: MUSB: unreliable OTG detection in host mode Date: Fri, 31 Aug 2007 17:29:03 -0700 Message-ID: <46D8B24F.3010409@mvista.com> References: <46D8ACD1.8030101@mvista.com> <20070901002025.B8E79235120@adsl-69-226-248-13.dsl.pltn13.pacbell.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20070901002025.B8E79235120@adsl-69-226-248-13.dsl.pltn13.pacbell.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-omap-open-source-bounces@linux.omap.com Errors-To: linux-omap-open-source-bounces@linux.omap.com To: David Brownell Cc: linux-omap-open-source@linux.omap.com List-Id: linux-omap@vger.kernel.org David Brownell wrote: >> On 2430, I've noticed that using the driver built in OTG mode, the >> detection of devices in host-mode is unreliable. > > Unreliable in what way(s)? Meaning it sometimes detects connected devices and sometimes not. Sometimes a reboot and another try helps. But with recent git it seems to never detect devices. > >> Building the driver in >> only host mode doesn't have any problems with the same devices connected. >> >> I load the musb_hdrc module, then the g_zero module to initiate OTG >> detection. >> >> If my board is connected as a gadget, this works just fine, but if my >> board is the host and I have devices connected, the detection doesn't >> work reliably. In the past it seemed it would work most of the time, >> but with the latest kernel, it doesn't seem to work at all. > > This somewhat resembles a problem I've not tracked down, whereby > the 2420 + TUSB6010-EVM, in OTG mode, seems to recieve garbage > when reading descriptors from the high speed hub I usually like > to connect as a root device. > > DaVinci didn't seem to have any such issues... > I haven't tested DaVinci in OTG mode since on the EVM board I have, you have to move a jumper to switch between the two. Kevin