Re: [PATCH v2 1/5] usb: dwc2: gadget: use ep->fifo_index in context of FIFO registers

From: Vahram Aharonyan
Date: Thu Feb 04 2016 - 07:25:23 EST


On 2/3/2016 3:40 PM, Robert Baldyga wrote:
> In context of FIFO registers we use ep->fifo_index instead of ep->index.
>
> Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx>
> ---
> drivers/usb/dwc2/gadget.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index 422ab7d..0d0f6fe 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -369,7 +369,8 @@ static int dwc2_hsotg_write_fifo(struct dwc2_hsotg *hsotg,
> return -ENOSPC;
> }
> } else if (hsotg->dedicated_fifos && hs_ep->index != 0) {
> - can_write = dwc2_readl(hsotg->regs + DTXFSTS(hs_ep->index));
> + can_write = dwc2_readl(hsotg->regs +
> + DTXFSTS(hs_ep->fifo_index));
>
> can_write &= 0xffff;
> can_write *= 4;
> @@ -2172,7 +2173,7 @@ static void kill_all_requests(struct dwc2_hsotg *hsotg,
>
> if (!hsotg->dedicated_fifos)
> return;
> - size = (dwc2_readl(hsotg->regs + DTXFSTS(ep->index)) & 0xffff) * 4;
> + size = (dwc2_readl(hsotg->regs + DTXFSTS(ep->fifo_index)) & 0xffff) * 4;
> if (size < ep->fifo_size)
> dwc2_hsotg_txfifo_flush(hsotg, ep->fifo_index);
> }
>

Hi Robert,

DTXFSTS register is linked with endpoint, not FIFO - it contains information about how much space is used in the FIFO assigned to the endpoint. Changing ep->index to ep->fifo_index will work, if FIFO number assigned to that endpoint coincides with ep->index. For example, TX FIFO #1 has been assigned to EP 1 In. If TX FIFO #2 was assigned to EP #1, then with this change DTXFSTS[2] will be used instead of DTXFSTS[1] for EP #1.

Thanks,
Vahram.