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SubjectRe: [PATCH] fsl_usb2_udc: Add a wmb before priming endpoint.
On Tue, Jun 03, 2008 at 04:20:25PM +0100, Will Newton wrote:
> Add a wmb to fsl_queue_td before priming the endpoint. This ensures that the
> modifications to the QH are seen by the hardware.
>
> Signed-off-by: Will Newton <will.newton@gmail.com>
> ---
> drivers/usb/gadget/fsl_usb2_udc.c | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/usb/gadget/fsl_usb2_udc.c
> b/drivers/usb/gadget/fsl_usb2_udc.c
> index 1868754..dd06a5b 100644
> --- a/drivers/usb/gadget/fsl_usb2_udc.c
> +++ b/drivers/usb/gadget/fsl_usb2_udc.c
> @@ -653,6 +653,8 @@ static int fsl_queue_td(struct fsl_ep *ep, struct
> fsl_req *req)
> | EP_QUEUE_HEAD_STATUS_HALT));
> dQH->size_ioc_int_sts &= temp;
>
> + wmb();

checkpatch.pl will complain that there's not comment above the memory
barrier. Could you just add it and in one line summarize why wmb()??

> +
> /* Prime endpoint by writing 1 to ENDPTPRIME */
> temp = ep_is_in(ep)
> ? (1 << (ep_index(ep) + 16))
> --
> 1.5.5.2



--
Best Regards,

Felipe Balbi
me@felipebalbi.com
http://blog.felipebalbi.com


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