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From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
To: broonie@kernel.org
Cc: alsa-devel@alsa-project.org, patches@opensource.wolfsonmicro.com,
	lgirdwood@gmail.com
Subject: [PATCH] ASoC: arizona: Add 32uS delay after putting FLL into freerun
Date: Thu, 26 Nov 2015 14:03:20 +0000	[thread overview]
Message-ID: <1448546600-15596-1-git-send-email-ckeepax@opensource.wolfsonmicro.com> (raw)

When switching between two clock sources using the FLL freerun to smooth
the transition we should wait 32uS after putting the FLL into freerun
before we proceed. In practice we appear to be getting enough delay from
the surrounding code, but better to make it explicit.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
 sound/soc/codecs/arizona.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/sound/soc/codecs/arizona.c b/sound/soc/codecs/arizona.c
index e76ecc7..8cd448c 100644
--- a/sound/soc/codecs/arizona.c
+++ b/sound/soc/codecs/arizona.c
@@ -2215,6 +2215,7 @@ static int arizona_enable_fll(struct arizona_fll *fll)
 		regmap_update_bits_async(fll->arizona->regmap, fll->base + 1,
 					 ARIZONA_FLL1_FREERUN,
 					 ARIZONA_FLL1_FREERUN);
+		udelay(32);
 	}
 
 	/*
-- 
1.7.2.5

             reply	other threads:[~2015-11-26 14:19 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-26 14:03 Charles Keepax [this message]
2015-11-27 12:26 ` [PATCH] ASoC: arizona: Add 32uS delay after putting FLL into freerun Mark Brown
2015-11-27 13:05   ` Charles Keepax
  -- strict thread matches above, loose matches on Subject: below --
2015-11-30 17:37 Charles Keepax

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