From 08f416da209fad3a103469b975a853f25eda25e0 Mon Sep 17 00:00:00 2001
From: Sugar Zhang <sugar.zhang@rock-chips.com>
Date: Fri, 11 Aug 2023 16:10:36 +0800
Subject: [PATCH] ASoC: rockchip: i2s: Fix register access in probe

MUST: after pm_runtime_enable step, any register R/W
should be wrapped with pm_runtime_get_sync/put.

Another approach is to enable the regcache true to
avoid access HW registers.

Alternatively, performing the registers R/W before
pm_runtime_enable is also a good option.

Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Change-Id: I9c495361fcb7fb0a06fe1538d05b94617e332756
---
 sound/soc/rockchip/rockchip_i2s.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/sound/soc/rockchip/rockchip_i2s.c b/sound/soc/rockchip/rockchip_i2s.c
index aff6cbf7fc95..6a02002d020f 100644
--- a/sound/soc/rockchip/rockchip_i2s.c
+++ b/sound/soc/rockchip/rockchip_i2s.c
@@ -897,6 +897,20 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = rockchip_i2s_init_dai(i2s, res, &dai);
+	if (ret)
+		goto err_clk;
+
+	/*
+	 * MUST: after pm_runtime_enable step, any register R/W
+	 * should be wrapped with pm_runtime_get_sync/put.
+	 *
+	 * Another approach is to enable the regcache true to
+	 * avoid access HW registers.
+	 *
+	 * Alternatively, performing the registers R/W before
+	 * pm_runtime_enable is also a good option.
+	 */
 	pm_runtime_enable(&pdev->dev);
 	if (!pm_runtime_enabled(&pdev->dev)) {
 		ret = i2s_runtime_resume(&pdev->dev);
@@ -904,10 +918,6 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
 			goto err_pm_disable;
 	}
 
-	ret = rockchip_i2s_init_dai(i2s, res, &dai);
-	if (ret)
-		goto err_pm_disable;
-
 	ret = devm_snd_soc_register_component(&pdev->dev,
 					      &rockchip_i2s_component,
 					      dai, 1);
@@ -935,7 +945,7 @@ err_suspend:
 		i2s_runtime_suspend(&pdev->dev);
 err_pm_disable:
 	pm_runtime_disable(&pdev->dev);
-
+err_clk:
 	clk_disable_unprepare(i2s->hclk);
 
 	return ret;