On Wed, May 27, 2009 at 04:13:13PM +0100, Warren, Dean wrote: > Good point Alan. I will forward to the maintainers as well. > > Thanks for your help so far. I will endeavour to find out more about the > host controller chip / driver. > > -----Original Message----- > From: Alan Stern [mailto:stern@xxxxxxxxxxxxxxxxxxx] > Sent: 27 May 2009 15:24 > To: Warren, Dean > Cc: linux-usb@xxxxxxxxxxxxxxx > Subject: RE: sierra_write - usb_submit_urb(write bulk) failed with > status = -12 > > On Wed, 27 May 2009, Warren, Dean wrote: > > > OK cheers Alan. > > > > Please note there was a typo in my original post: it's not possible > > for the function oxu210hp-hcd.c::qh_urb_transaction() to return NULL > > and 'not call cleanup' unless ehci_qtd_alloc() fails and it doesn't. > > :( It's been a long day! > > > > So oxu210hp-hcd.c::__oxu_urb_enqueue() calls > > oxu210hp-hcd.c::qh_urb_transaction() at line 1358 which fails with 0 > > because as you stated oxu210hp-hcd.c::oxu_buf_alloc() is failing and > > returning ENOMEM (the last ENOMEM in the function). > > > > Looking at the source this is because a 'suitable available data > > buffer' can not be found. Why might this be? > > Shouldn't you be directing these questions to the author or maintainer > of the oxu210hp driver in addition to posting them on a general-purpose > mailing list? > > The reason for that last -ENOMEM is explained in the comments preceding > the function. There is only a limited amount of memory available on > the chip, and evidently it isn't enough for your driver. The very small memory buffer of the controller is a big issue for the driver since some bulk messages cannot be managed at all... Ciao, Rodolfo -- GNU/Linux Solutions e-mail: giometti@xxxxxxxxxxxx Linux Device Driver giometti@xxxxxxxx Embedded Systems phone: +39 349 2432127 UNIX programming skype: rodolfo.giometti -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
