Re: [PATCH] mfd: exynos-lpass: Handle return value of clk_prepare_enable

From: Arvind Yadav
Date: Wed Aug 09 2017 - 00:41:17 EST


Thanks :)


On Tuesday 08 August 2017 11:55 PM, Krzysztof Kozlowski wrote:
On Tue, Aug 08, 2017 at 05:20:55PM +0530, Arvind Yadav wrote:
clk_prepare_enable() can fail here and we must check its return value.
we must call pm_runtime_disable() and pm_runtime_set_suspended(),
If exynos_lpass_probe is not successful.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
This is not a trivial change so please mark all such patches as RFT.
Submit checklist mentions testing in multiple steps and last time your
ASoC changes were not tested.
I will ask for RFT.

---
drivers/mfd/exynos-lpass.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
index ca829f8..c74ff62 100644
--- a/drivers/mfd/exynos-lpass.c
+++ b/drivers/mfd/exynos-lpass.c
@@ -73,9 +73,13 @@ static void exynos_lpass_core_sw_reset(struct exynos_lpass *lpass, int mask)
regmap_write(lpass->top, SFR_LPASS_CORE_SW_RESET, val);
}
-static void exynos_lpass_enable(struct exynos_lpass *lpass)
+static int exynos_lpass_enable(struct exynos_lpass *lpass)
{
- clk_prepare_enable(lpass->sfr0_clk);
+ int ret;
+
+ ret = clk_prepare_enable(lpass->sfr0_clk);
+ if (ret)
+ return ret;
/* Unmask SFR, DMA and I2S interrupt */
regmap_write(lpass->top, SFR_LPASS_INTR_CA5_MASK,
@@ -87,6 +91,8 @@ static void exynos_lpass_enable(struct exynos_lpass *lpass)
exynos_lpass_core_sw_reset(lpass, LPASS_I2S_SW_RESET);
exynos_lpass_core_sw_reset(lpass, LPASS_DMA_SW_RESET);
exynos_lpass_core_sw_reset(lpass, LPASS_MEM_SW_RESET);
+
+ return 0;
}
static void exynos_lpass_disable(struct exynos_lpass *lpass)
@@ -112,6 +118,7 @@ static int exynos_lpass_probe(struct platform_device *pdev)
struct exynos_lpass *lpass;
void __iomem *base_top;
struct resource *res;
+ int ret;
lpass = devm_kzalloc(dev, sizeof(*lpass), GFP_KERNEL);
if (!lpass)
@@ -136,8 +143,12 @@ static int exynos_lpass_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, lpass);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
- exynos_lpass_enable(lpass);
-
+ ret = exynos_lpass_enable(lpass);
+ if (ret) {
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
You need also regmap_exit().

+ return ret;
+ }
Leave one blank line before return.

Best regards,
Krzysztof

~arvind