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[PATCH] USB: EHCI full speed ISO bugfixes

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This patch replaces the split ISO raw_mask calculation code in the
iso_stream_init() function that computed incorrect numbers of high
speed transactions for both input and output transfers.

In the output case, it added a superfluous start-split transaction for
all maxmimum packet sizes that are a multiple of 188.

In the input case, it forgot to add complete-split transactions for all
microframes covered by the full speed transaction, and the additional
complete-split transaction needed for the case when full speed data
starts arriving near the end of a microframe.

These changes don't affect the lack of full speed bandwidth, but at
least it removes the MMF errors that the HC raised with some input
streams.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Clemens Ladisch 2006-01-20 13:49:10 -08:00 committed by Greg Kroah-Hartman
parent f8aeb3bb86
commit 469d02293d
1 changed files with 6 additions and 5 deletions
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11
drivers/usb/host/ehci-sched.c
View file

@ -707,6 +707,7 @@ iso_stream_init (
} else {
u32 addr;
int think_time;
int hs_transfers;
addr = dev->ttport << 24;
if (!ehci_is_TDI(ehci)
@ -719,6 +720,7 @@ iso_stream_init (
think_time = dev->tt ? dev->tt->think_time : 0;
stream->tt_usecs = NS_TO_US (think_time + usb_calc_bus_time (
dev->speed, is_input, 1, maxp));
hs_transfers = max (1u, (maxp + 187) / 188);
if (is_input) {
u32 tmp;
@ -727,12 +729,11 @@ iso_stream_init (
stream->usecs = HS_USECS_ISO (1);
stream->raw_mask = 1;
/* pessimistic c-mask */
tmp = usb_calc_bus_time (USB_SPEED_FULL, 1, 0, maxp)
/ (125 * 1000);
stream->raw_mask |= 3 << (tmp + 9);
/* c-mask as specified in USB 2.0 11.18.4 3.c */
tmp = (1 << (hs_transfers + 2)) - 1;
stream->raw_mask |= tmp << (8 + 2);
} else
stream->raw_mask = smask_out [maxp / 188];
stream->raw_mask = smask_out [hs_transfers - 1];
bandwidth = stream->usecs + stream->c_usecs;
bandwidth /= 1 << (interval + 2);