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From: Axel Lin <axel.lin@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Kenneth Kiraly <kiraly@lab126.com>,
	Mark Brown <broonie@opensource.wolfsonmicro.com>,
	Liam Girdwood <lrg@ti.com>,
	alsa-devel@alsa-project.org
Subject: [RFC][PATCH] ASoC: Avoid writing to WM8971_RESET in wm8971_resume
Date: Tue, 04 Oct 2011 07:44:22 +0800	[thread overview]
Message-ID: <1317685462.3640.2.camel@phoenix> (raw)

Writing to WM8971_RESET resets all registers to the default state.
Thus we should avoid writing to WM8971_RESET on resume.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
Hi,
While reading the code, I don't understand why we need to do (in wm8971_resume):

for (i = 0; i < ARRAY_SIZE(wm8971_reg); i++) {
        if (i + 1 == WM8971_RESET)
                continue;

My understanding is that we want to avoid writing to WM8971_RESET on resume.
Thus I send this patch for review.
I don't have the hardware for testing, I'd appreciate if someone can test this patch.

Thanks,
Axel

 sound/soc/codecs/wm8971.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sound/soc/codecs/wm8971.c b/sound/soc/codecs/wm8971.c
index 572bb80..7ec4165 100644
--- a/sound/soc/codecs/wm8971.c
+++ b/sound/soc/codecs/wm8971.c
@@ -612,7 +612,7 @@ static int wm8971_resume(struct snd_soc_codec *codec)
 
 	/* Sync reg_cache with the hardware */
 	for (i = 0; i < ARRAY_SIZE(wm8971_reg); i++) {
-		if (i + 1 == WM8971_RESET)
+		if (i == WM8971_RESET)
 			continue;
 		data[0] = (i << 1) | ((cache[i] >> 8) & 0x0001);
 		data[1] = cache[i] & 0x00ff;
-- 
1.7.4.1

             reply	other threads:[~2011-10-03 23:44 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-03 23:44 Axel Lin [this message]
2011-10-04 15:04 ` [RFC][PATCH] ASoC: Avoid writing to WM8971_RESET in wm8971_resume Mark Brown
2011-10-04 15:04   ` Mark Brown

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