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ARM: 6440/1: ep93xx: DMA: fix channel_disable

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When channel_disable() is called, it disables per channel interrupts and
waits until channels state becomes STATE_STALL, and then disables the
channel. Now, if the DMA transfer is disabled while the channel is in
STATE_NEXT we will not wait anything and disable the channel immediately.
This seems to cause weird data corruption for example in audio transfers.

Fix is to wait while we are in STATE_NEXT or STATE_ON and only then
disable the channel.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Acked-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Mika Westerberg 2010-10-12 10:37:59 +01:00 committed by Russell King
parent c0bb5862a9
commit 10d48b3934
1 changed files with 1 additions and 1 deletions
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2
arch/arm/mach-ep93xx/dma-m2p.c
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@ -276,7 +276,7 @@ static void channel_disable(struct m2p_channel *ch)
v &= ~(M2P_CONTROL_STALL_IRQ_EN | M2P_CONTROL_NFB_IRQ_EN);
m2p_set_control(ch, v);
while (m2p_channel_state(ch) == STATE_ON)
while (m2p_channel_state(ch) >= STATE_ON)
cpu_relax();
m2p_set_control(ch, 0x0);