Messages in this thread |  | | Date | Wed, 10 Oct 2001 00:51:12 -0400 | From | Pete Zaitcev <> | Subject | Re: usb_bulk_msg timeout w/ rvmalloc |
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> I have written a driver which, in part, facilitates the usb bulk > transfer of raw image data. It works fine for small (CIF, QCIF) > images, but for larger images, kmalloc will not allocate enough > memory.
How much do you need?
> I copied the rvmalloc code from the cpia2 driver and used it in place > of kmalloc. The memory allocates fine, but usb_bulk_msg now times out > when using the pointer to the rvmalloc'd memory. I have been unable to > find an instance of an existing driver using rvmalloc in conjunction > with usb_bulk_msg.
The best thing would be to use pipelined transfer with several URBs, I think. If that is too difficult for you, try to use __get_free_pages(), but mind that even if free RAM is available, kernel may not be able to fulfill your request. Check response codes carefuly.
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