Commit 170c0263 authored by Sarah Sharp's avatar Sarah Sharp Committed by Greg Kroah-Hartman
Browse files

xhci: Fix mult base in endpoint bandwidth info. 



The "Mult" bits in the SuperSpeed Endpoint Companion Descriptor are
zero-based, and the xHCI host controller wants them to be zero-based in
the input context.  However, for the bandwidth math, we want them to be
one-based.  Fix this.

Fix the documentation about the endpoint bandwidth mult variable in the
xhci.h file, which says it is zero-based.  Also fix the documentation
about num_packets, which is also one-based, not zero-based.

Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 75d7cf72

drivers/usb/host/xhci-mem.c

+5 −4
Original line number Diff line number Diff line
@@ -1473,11 +1473,12 @@ void xhci_update_bw_info(struct xhci_hcd *xhci, 
			/* Added or changed endpoint */

			bw_info->ep_interval = CTX_TO_EP_INTERVAL(

					le32_to_cpu(ep_ctx->ep_info));

			bw_info->mult = CTX_TO_EP_MULT(

					le32_to_cpu(ep_ctx->ep_info));

			/* Number of packets is zero-based in the input context,

			 * but we want one-based for the interval table.

			/* Number of packets and mult are zero-based in the

			 * input context, but we want one-based for the

			 * interval table.

			 */

			bw_info->mult = CTX_TO_EP_MULT(

					le32_to_cpu(ep_ctx->ep_info)) + 1;

			bw_info->num_packets = CTX_TO_MAX_BURST(

					le32_to_cpu(ep_ctx->ep_info2)) + 1;

			bw_info->max_packet_size = MAX_PACKET_DECODED(

drivers/usb/host/xhci.h

+2 −1
Original line number Diff line number Diff line
@@ -747,8 +747,9 @@ struct xhci_stream_info { 
 * (DMI) also limits the total bandwidth (across all domains) that can be used.

 */

struct xhci_bw_info {

	/* ep_interval is zero-based */

	unsigned int		ep_interval;

	/* mult and num_packets are zero-based */

	/* mult and num_packets are one-based */

	unsigned int		mult;

	unsigned int		num_packets;

	unsigned int		max_packet_size;

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