ALSA: firewire-lib: fix to check cycle continuity

commit 77ce96543b03f437c6b45f286d8110db2b6622a3 upstream.

The local helper function to compare the given pair of cycle count
evaluates them. If the left value is less than the right value, the
function returns negative value.

If the safe cycle is less than the current cycle, it is the case of
cycle lost. However, it is not currently handled properly.

This commit fixes the bug.

Cc: <stable@vger.kernel.org>
Fixes: 705794c53b ("ALSA: firewire-lib: check cycle continuity")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20240218033026.72577-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Takashi Sakamoto 2024-02-18 12:30:26 +09:00 коммит произвёл Greg Kroah-Hartman
Родитель 7d930a4da1
Коммит cbf67001d6
1 изменённых файлов: 1 добавлений и 1 удалений

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@ -934,7 +934,7 @@ static int generate_device_pkt_descs(struct amdtp_stream *s,
// to the reason.
unsigned int safe_cycle = increment_ohci_cycle_count(next_cycle,
IR_JUMBO_PAYLOAD_MAX_SKIP_CYCLES);
lost = (compare_ohci_cycle_count(safe_cycle, cycle) > 0);
lost = (compare_ohci_cycle_count(safe_cycle, cycle) < 0);
}
if (lost) {
dev_err(&s->unit->device, "Detect discontinuity of cycle: %d %d\n",