[alsa-devel] [PATCH] ASoC: tlv320dac33: Add guarding parentheses to macros

Axel Lin axel.lin at gmail.com
Thu Sep 29 06:09:57 CEST 2011


Put parentheses around macro argument uses. This avoids pitfalls
for the programmer, where the argument expansion does not give the
expected result, for example:

SAMPLES_TO_US(substream->runtime->rate, dac33->uthr - DAC33_MODE7_MARGIN + 1);

Signed-off-by: Axel Lin <axel.lin at gmail.com>
---
 sound/soc/codecs/tlv320dac33.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/sound/soc/codecs/tlv320dac33.c b/sound/soc/codecs/tlv320dac33.c
index 243d177..389b1c2 100644
--- a/sound/soc/codecs/tlv320dac33.c
+++ b/sound/soc/codecs/tlv320dac33.c
@@ -55,13 +55,13 @@
 #define BURST_BASEFREQ_HZ	49152000
 
 #define SAMPLES_TO_US(rate, samples) \
-	(1000000000 / ((rate * 1000) / samples))
+	(1000000000 / (((rate) * 1000) / (samples)))
 
 #define US_TO_SAMPLES(rate, us) \
-	(rate / (1000000 / (us < 1000000 ? us : 1000000)))
+	((rate) / (1000000 / ((us) < 1000000 ? (us) : 1000000)))
 
 #define UTHR_FROM_PERIOD_SIZE(samples, playrate, burstrate) \
-	((samples * 5000) / ((burstrate * 5000) / (burstrate - playrate)))
+	(((samples)*5000) / (((burstrate)*5000) / ((burstrate) - (playrate))))
 
 static void dac33_calculate_times(struct snd_pcm_substream *substream);
 static int dac33_prepare_chip(struct snd_pcm_substream *substream);
-- 
1.7.4.1





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