2017-08-09 04:48:39

by Arvind Yadav

[permalink] [raw]
Subject: [RFT v2] mfd: exynos-lpass: Handle return value of clk_prepare_enable

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 <[email protected]>
---
changes in v2:
added regmap_exit(lpass->top) and blank line before return.

drivers/mfd/exynos-lpass.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
index ca829f8..1ab7210 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)
@@ -136,7 +143,13 @@ 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);
+ regmap_exit(lpass->top);
+ return ret;
+ }

return devm_of_platform_populate(dev);
}
@@ -167,9 +180,7 @@ static int __maybe_unused exynos_lpass_resume(struct device *dev)
{
struct exynos_lpass *lpass = dev_get_drvdata(dev);

- exynos_lpass_enable(lpass);
-
- return 0;
+ return exynos_lpass_enable(lpass);
}

static const struct dev_pm_ops lpass_pm_ops = {
--
1.9.1


2017-08-10 06:01:48

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [RFT v2] mfd: exynos-lpass: Handle return value of clk_prepare_enable

On Wed, Aug 09, 2017 at 10:18:10AM +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 <[email protected]>
> ---
> changes in v2:
> added regmap_exit(lpass->top) and blank line before return.
>
> drivers/mfd/exynos-lpass.c | 23 +++++++++++++++++------
> 1 file changed, 17 insertions(+), 6 deletions(-)
>

For me looks ok although this requires testing and I do not have
Exynos with LPASS (e.g. Exynos5433). Maybe folks from Samsung (Polish
R&D or HQ as they are working on it) could help (Cced).

Best regards,
Krzysztof

> diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
> index ca829f8..1ab7210 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)
> @@ -136,7 +143,13 @@ 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);
> + regmap_exit(lpass->top);
> + return ret;
> + }
>
> return devm_of_platform_populate(dev);
> }
> @@ -167,9 +180,7 @@ static int __maybe_unused exynos_lpass_resume(struct device *dev)
> {
> struct exynos_lpass *lpass = dev_get_drvdata(dev);
>
> - exynos_lpass_enable(lpass);
> -
> - return 0;
> + return exynos_lpass_enable(lpass);
> }
>
> static const struct dev_pm_ops lpass_pm_ops = {
> --
> 1.9.1
>

2017-08-10 06:24:41

by Marek Szyprowski

[permalink] [raw]
Subject: Re: [RFT v2] mfd: exynos-lpass: Handle return value of clk_prepare_enable

Hi All,

On 2017-08-10 08:01, Krzysztof Kozlowski wrote:
> On Wed, Aug 09, 2017 at 10:18:10AM +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 <[email protected]>
>> ---
>> changes in v2:
>> added regmap_exit(lpass->top) and blank line before return.
>>
>> drivers/mfd/exynos-lpass.c | 23 +++++++++++++++++------
>> 1 file changed, 17 insertions(+), 6 deletions(-)
>>
> For me looks ok although this requires testing and I do not have
> Exynos with LPASS (e.g. Exynos5433). Maybe folks from Samsung (Polish
> R&D or HQ as they are working on it) could help (Cced).

Works fine on Exynos5433 based TM2e.

Tested-by: Marek Szyprowski <[email protected]>

>
> Best regards,
> Krzysztof
>
>> diff --git a/drivers/mfd/exynos-lpass.c b/drivers/mfd/exynos-lpass.c
>> index ca829f8..1ab7210 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)
>> @@ -136,7 +143,13 @@ 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);
>> + regmap_exit(lpass->top);
>> + return ret;
>> + }
>>
>> return devm_of_platform_populate(dev);
>> }
>> @@ -167,9 +180,7 @@ static int __maybe_unused exynos_lpass_resume(struct device *dev)
>> {
>> struct exynos_lpass *lpass = dev_get_drvdata(dev);
>>
>> - exynos_lpass_enable(lpass);
>> -
>> - return 0;
>> + return exynos_lpass_enable(lpass);
>> }
>>
>> static const struct dev_pm_ops lpass_pm_ops = {
>> --
>> 1.9.1

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland