[PATCH 1/3] clk: exynos-audss: Keep the parent of mout_audss always enabled

Tushar Behera tushar.b at samsung.com
Tue Jun 10 22:32:17 PDT 2014


When the output clock of AUDSS mux is disabled, we are getting kernel
oops while doing a clk_get() on other clocks provided by AUDSS. Though
user manual doesn't specify this dependency, we came across this issue
while disabling the parent of AUDSS mux clocks.

Keeping the parents of AUDSS mux always enabled fixes this issue.

Signed-off-by: Tushar Behera <tushar.b at samsung.com>
Signed-off-by: Shaik Ameer Basha <shaik.ameer at samsung.com>
---
 drivers/clk/samsung/clk-exynos-audss.c |   17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos-audss.c b/drivers/clk/samsung/clk-exynos-audss.c
index 13eae14c..1542f30 100644
--- a/drivers/clk/samsung/clk-exynos-audss.c
+++ b/drivers/clk/samsung/clk-exynos-audss.c
@@ -30,6 +30,8 @@ static struct clk **clk_table;
 static void __iomem *reg_base;
 static struct clk_onecell_data clk_data;
 
+static struct clk *pll_ref, *pll_in;
+
 #define ASS_CLK_SRC 0x0
 #define ASS_CLK_DIV 0x4
 #define ASS_CLK_GATE 0x8
@@ -83,7 +85,7 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
 	const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
 	const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
 	const char *sclk_pcm_p = "sclk_pcm0";
-	struct clk *pll_ref, *pll_in, *cdclk, *sclk_audio, *sclk_pcm_in;
+	struct clk *cdclk, *sclk_audio, *sclk_pcm_in;
 	const struct of_device_id *match;
 	enum exynos_audss_clk_type variant;
 
@@ -113,10 +115,14 @@ static int exynos_audss_clk_probe(struct platform_device *pdev)
 
 	pll_ref = devm_clk_get(&pdev->dev, "pll_ref");
 	pll_in = devm_clk_get(&pdev->dev, "pll_in");
-	if (!IS_ERR(pll_ref))
+	if (!IS_ERR(pll_ref)) {
 		mout_audss_p[0] = __clk_get_name(pll_ref);
-	if (!IS_ERR(pll_in))
+		clk_prepare_enable(pll_ref);
+	}
+	if (!IS_ERR(pll_in)) {
 		mout_audss_p[1] = __clk_get_name(pll_in);
+		clk_prepare_enable(pll_in);
+	}
 	clk_table[EXYNOS_MOUT_AUDSS] = clk_register_mux(NULL, "mout_audss",
 				mout_audss_p, ARRAY_SIZE(mout_audss_p),
 				CLK_SET_RATE_NO_REPARENT,
@@ -217,6 +223,11 @@ static int exynos_audss_clk_remove(struct platform_device *pdev)
 			clk_unregister(clk_table[i]);
 	}
 
+	if (!IS_ERR(pll_in))
+		clk_disable_unprepare(pll_in);
+	if (!IS_ERR(pll_ref))
+		clk_disable_unprepare(pll_ref);
+
 	return 0;
 }
 
-- 
1.7.9.5




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