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From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
To:     broonie@kernel.org
Cc:     lgirdwood@gmail.com, perex@perex.cz, tiwai@suse.com,
        pierre-louis.bossart@linux.intel.com, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Amit Pundir <amit.pundir@linaro.org>
Subject: [PATCH] ASoC: codecs: wcd934x: do not switch off SIDO Buck when codec is in use
Date:   Thu,  7 Apr 2022 10:43:13 +0100
Message-Id: <20220407094313.2880-1-srinivas.kandagatla@linaro.org>
MIME-Version: 1.0
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Precedence: bulk

SIDO(Single-Inductor Dual-Ouput) Buck powers up both analog and digital
circuits along with internal memory, powering off this is the last thing
that codec should do when going to very low power.

Current code was powering off this Buck if there are no users of sysclk,
which is not correct. Powering off this buck will result in no register access.
This code path was never tested until recently after adding pm support
in SoundWire controller. Fix this by removing the buck poweroff when the
codec is active and also the code that is not used.

Without this patch all the read/write transactions will never complete and
results in SLIMBus Errors like:

qcom,slim-ngd qcom,slim-ngd.1: Tx:MT:0x0, MC:0x60, LA:0xcf failed:-110
wcd934x-codec wcd934x-codec.1.auto: ASoC: error at soc_component_read_no_lock
	on wcd934x-codec.1.auto for register: [0x00000d05] -110
qcom,slim-ngd-ctrl 171c0000.slim: Error Interrupt received 0x82000000

Reported-by: Amit Pundir <amit.pundir@linaro.org>
Fixes: a61f3b4f476e ("ASoC: wcd934x: add support to wcd9340/wcd9341 codec")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 sound/soc/codecs/wcd934x.c | 26 +-------------------------
 1 file changed, 1 insertion(+), 25 deletions(-)

diff --git a/sound/soc/codecs/wcd934x.c b/sound/soc/codecs/wcd934x.c
index 1e75e93cf28f..6298ebe96e94 100644
--- a/sound/soc/codecs/wcd934x.c
+++ b/sound/soc/codecs/wcd934x.c
@@ -1274,29 +1274,7 @@ static int wcd934x_set_sido_input_src(struct wcd934x_codec *wcd, int sido_src)
 	if (sido_src == wcd->sido_input_src)
 		return 0;
 
-	if (sido_src == SIDO_SOURCE_INTERNAL) {
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_BUCK_CTL,
-				   WCD934X_ANA_BUCK_HI_ACCU_EN_MASK, 0);
-		usleep_range(100, 110);
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_BUCK_CTL,
-				   WCD934X_ANA_BUCK_HI_ACCU_PRE_ENX_MASK, 0x0);
-		usleep_range(100, 110);
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_RCO,
-				   WCD934X_ANA_RCO_BG_EN_MASK, 0);
-		usleep_range(100, 110);
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_BUCK_CTL,
-				   WCD934X_ANA_BUCK_PRE_EN1_MASK,
-				   WCD934X_ANA_BUCK_PRE_EN1_ENABLE);
-		usleep_range(100, 110);
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_BUCK_CTL,
-				   WCD934X_ANA_BUCK_PRE_EN2_MASK,
-				   WCD934X_ANA_BUCK_PRE_EN2_ENABLE);
-		usleep_range(100, 110);
-		regmap_update_bits(wcd->regmap, WCD934X_ANA_BUCK_CTL,
-				   WCD934X_ANA_BUCK_HI_ACCU_EN_MASK,
-				   WCD934X_ANA_BUCK_HI_ACCU_ENABLE);
-		usleep_range(100, 110);
-	} else if (sido_src == SIDO_SOURCE_RCO_BG) {
+	if (sido_src == SIDO_SOURCE_RCO_BG) {
 		regmap_update_bits(wcd->regmap, WCD934X_ANA_RCO,
 				   WCD934X_ANA_RCO_BG_EN_MASK,
 				   WCD934X_ANA_RCO_BG_ENABLE);
@@ -1382,8 +1360,6 @@ static int wcd934x_disable_ana_bias_and_syclk(struct wcd934x_codec *wcd)
 	regmap_update_bits(wcd->regmap, WCD934X_CLK_SYS_MCLK_PRG,
 			   WCD934X_EXT_CLK_BUF_EN_MASK |
 			   WCD934X_MCLK_EN_MASK, 0x0);
-	wcd934x_set_sido_input_src(wcd, SIDO_SOURCE_INTERNAL);
-
 	regmap_update_bits(wcd->regmap, WCD934X_ANA_BIAS,
 			   WCD934X_ANA_BIAS_EN_MASK, 0);
 	regmap_update_bits(wcd->regmap, WCD934X_ANA_BIAS,
-- 
2.21.0