Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 92bc3648 authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Greg Kroah-Hartman
Browse files

USB: EHCI: fix ITD list order 



When isochronous URBs are shorter than one frame and when more than one
ITD in a frame has been completed before the interrupt can be handled,
scan_periodic() completes the URBs in the order in which they are found
in the descriptor list.  Therefore, the descriptor list must contain the
ITDs in the correct order, i.e., a new ITD must be linked in after any
previous ITDs of the same endpoint.

This should fix garbled capture data in the USB audio drivers.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
Reported-by: default avatarColin Fletcher <colin.m.fletcher@googlemail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent bf162019

drivers/usb/host/ehci-sched.c

+19 −5
Original line number Diff line number Diff line
@@ -1565,13 +1565,27 @@ itd_patch( 
static inline void

itd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_itd *itd)

{

	/* always prepend ITD/SITD ... only QH tree is order-sensitive */

	itd->itd_next = ehci->pshadow [frame];

	itd->hw_next = ehci->periodic [frame];

	ehci->pshadow [frame].itd = itd;

	union ehci_shadow	*prev = &ehci->pshadow[frame];

	__hc32			*hw_p = &ehci->periodic[frame];

	union ehci_shadow	here = *prev;

	__hc32			type = 0;



	/* skip any iso nodes which might belong to previous microframes */

	while (here.ptr) {

		type = Q_NEXT_TYPE(ehci, *hw_p);

		if (type == cpu_to_hc32(ehci, Q_TYPE_QH))

			break;

		prev = periodic_next_shadow(ehci, prev, type);

		hw_p = shadow_next_periodic(ehci, &here, type);

		here = *prev;

	}



	itd->itd_next = here;

	itd->hw_next = *hw_p;

	prev->itd = itd;

	itd->frame = frame;

	wmb ();

	ehci->periodic[frame] = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD);

	*hw_p = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD);

}



/* fit urb's itds into the selected schedule slot; activate as needed */