Hi Try to allocate urb with GFP_KERNEL
Urb = usb_alloc_urb(0, GFP_KERNEL); Regards, Shalini -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Alan Stern Sent: Friday, July 22, 2005 8:40 AM To: Subbu Cc: linux-usb-devel@lists.sourceforge.net Subject: Re: [linux-usb-devel] problem with sending urb through bulk pipe.(callbacks not happening) On Thu, 21 Jul 2005, Subbu wrote: > > Hi, > > I am new to writing usb drivers for linux.plz help me. > > i am trying to send the urb through bulk pipe after allocating urb > with > > Urb = usb_alloc_urb(0); > > FILL_BULK_URB( Urb, > usbdevice, > usb_sndbulkpipe(usbdevice,bulk_out_endpointaddr), > (unsigned chr *)data, > size, > callback, > 0) > > and normal usb_start_wait_urb function which submits the urb with > usb_submit_urb and waits until the completion or wait until timeout. > > > and i have callback > > int callback(struct urb *) > { > > printk("call back function called \n"); > /* do some thing */ > > return status; > } > > > > Problem i am getting now is NO call backs are getting called. > > whateever the timeout i give with schedule_timeout function. > > > > what could be the reason of not getting the callbacks with > FILL_BULK_URB.?? > > how to debug the problem..? > > is it because pipes are into some stall condition or what..? You should not call usb_start_wait_urb; it's a private function for use by usbcore only. In fact you can't call it, since it's declared static in message.c. You should call usb_submit_urb directly, or else call usb_bulk_msg. Alan Stern ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_idt77&alloc_id492&op=click _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
