[alsa-devel] [PATCH] ASoC: rl6231: fix range of DMIC clock

John Lin john.lin at realtek.com
Mon Nov 16 07:41:07 CET 2015


The maximum DMIC clock rate is 3.072 MHz for most DMIC. And it will get better
performance in higher clock rate. If we set maximum to 3 MHz in driver, we will
get a clock rate which is not even close to 3 MHz.
For example, if DMIC clock source is 24.576 MHz, the DMIC clock will be about
1.5 MHz in current code. But it will be 3.072 MHz with this patch.

Signed-off-by: John Lin <john.lin at realtek.com>
---
 sound/soc/codecs/rl6231.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/rl6231.c b/sound/soc/codecs/rl6231.c
index 18b4292..1dc68ab 100644
--- a/sound/soc/codecs/rl6231.c
+++ b/sound/soc/codecs/rl6231.c
@@ -82,8 +82,8 @@ int rl6231_calc_dmic_clk(int rate)
 	for (i = 0; i < ARRAY_SIZE(div); i++) {
 		if ((div[i] % 3) == 0)
 			continue;
-		/* find divider that gives DMIC frequency below 3MHz */
-		if (3000000 * div[i] >= rate)
+		/* find divider that gives DMIC frequency below 3.072MHz */
+		if (3072000 * div[i] >= rate)
 			return i;
 	}
 
-- 
1.8.1.1.439.g50a6b54



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