linux-kernel - [PATCH] ASoC: wm8962: Use force clear for WM8962_SYSCLK

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Date:   Wed, 13 May 2020 13:30:35 +0800
From:   Shengjiu Wang <shengjiu.wang@....com>
To:     lgirdwood@...il.com, broonie@...nel.org, perex@...ex.cz,
        tiwai@...e.com, shengjiu.wang@....com, tglx@...utronix.de,
        allison@...utok.net, info@...ux.net, patches@...nsource.cirrus.com,
        alsa-devel@...a-project.org, linux-kernel@...r.kernel.org
Subject: [PATCH] ASoC: wm8962: Use force clear for WM8962_SYSCLK_ENA after reset

When CLOCKING2 is non-volatile register, we need force clear
the WM8962_SYSCLK_ENA bit after reset, for the value in cache
maybe 0 but in hardware it is 1. Otherwise there will issue
as below statement in driver.

/* SYSCLK defaults to on; make sure it is off so we can safely
 * write to registers if the device is declocked.

Fixes: c38b608504aa ("ASoC: wm8962: set CLOCKING2 as non-volatile register")
Signed-off-by: Shengjiu Wang <shengjiu.wang@....com>
---
 sound/soc/codecs/wm8962.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c
index 0a2cfff44441..08d19df8a700 100644
--- a/sound/soc/codecs/wm8962.c
+++ b/sound/soc/codecs/wm8962.c
@@ -3798,8 +3798,8 @@ static int wm8962_runtime_resume(struct device *dev)
 	/* SYSCLK defaults to on; make sure it is off so we can safely
 	 * write to registers if the device is declocked.
 	 */
-	regmap_update_bits(wm8962->regmap, WM8962_CLOCKING2,
-			   WM8962_SYSCLK_ENA, 0);
+	regmap_write_bits(wm8962->regmap, WM8962_CLOCKING2,
+			  WM8962_SYSCLK_ENA, 0);
 
 	/* Ensure we have soft control over all registers */
 	regmap_update_bits(wm8962->regmap, WM8962_CLOCKING2,
-- 
2.21.0