[PATCH resend 10/17] xhci: Setup HW retries correctly.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The xHCI host controller can be programmed to retry a transfer a certain number
of times per endpoint before it passes back an error condition to the host
controller driver.  The xHC will return an error code when the error count
transitions from 1 to 0.  Programming an error count of 3 means the xHC tries
the transfer 3 times, programming it with a 1 means it tries to transfer once,
and programming it with 0 means the HW tries the transfer infinitely.

We want isochronous transfers to only be tried once, so set the error count to
one.

Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
---
 drivers/usb/host/xhci-mem.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index ec825f1..075e103 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -480,11 +480,13 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
 
 	/* FIXME dig Mult and streams info out of ep companion desc */
 
-	/* Allow 3 retries for everything but isoc */
+	/* Allow 3 retries for everything but isoc;
+	 * error count = 0 means infinite retries.
+	 */
 	if (!usb_endpoint_xfer_isoc(&ep->desc))
 		ep_ctx->ep_info2 = ERROR_COUNT(3);
 	else
-		ep_ctx->ep_info2 = ERROR_COUNT(0);
+		ep_ctx->ep_info2 = ERROR_COUNT(1);
 
 	ep_ctx->ep_info2 |= xhci_get_endpoint_type(udev, ep);
 
-- 
1.5.6.5

--
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

[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux