ASoC: tlv320dac33: Limit the US_TO_SAMPLES macro

Limit the time window to maximum 1s in the macro.
The driver deals with much shorter times (<200ms).
This will fix a rare division by zero bug in Mode1.
This could happen, when the work is not executed in
time (within mode1_latency) after the interrupt.
In this case the DAC33 will not receive the needed
nSample command in time, and enters to an unknown
state, and won't recover.
In such event the time window will increase, and
eventually going to be bigger than 1s, resulting
devision by zero.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

diff --git a/sound/soc/codecs/tlv320dac33.c b/sound/soc/codecs/tlv320dac33.c
index fed14582b49845afe49fa3e91aae10b5beb70f8b..c47c20d21ea57446e88f36b3a75ac88b4cbe214b 100644 (file)
--- a/sound/soc/codecs/tlv320dac33.c
+++ b/sound/soc/codecs/tlv320dac33.c
@@ -58,7 +58,7 @@
        (1000000000 / ((rate * 1000) / samples))
 
 #define US_TO_SAMPLES(rate, us) \
-       (rate / (1000000 / us))
+       (rate / (1000000 / (us < 1000000 ? us : 1000000)))
 
 #define UTHR_FROM_PERIOD_SIZE(samples, playrate, burstrate) \
        ((samples * 5000) / ((burstrate * 5000) / (burstrate - playrate)))