2022-04-12 23:16:17

by Miaoqian Lin

Subject: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking

If the device is already in a runtime PM enabled state
pm_runtime_get_sync() will return 1, so a test for negative
value should be used to check for errors.

Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
Signed-off-by: Miaoqian Lin <[email protected]>
---
drivers/clk/imx/clk-scu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
index 083da31dc3ea..18c6190eeffd 100644
--- a/drivers/clk/imx/clk-scu.c
+++ b/drivers/clk/imx/clk-scu.c
@@ -529,7 +529,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
pm_runtime_enable(dev);

ret = pm_runtime_get_sync(dev);
- if (ret) {
+ if (ret < 0) {
pm_genpd_remove_device(dev);
pm_runtime_disable(dev);
return ret;
--
2.17.1

2022-04-19 00:27:15

by Abel Vesa

Subject: Re: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking

On 22-04-12 06:57:18, Miaoqian Lin wrote:
> If the device is already in a runtime PM enabled state
> pm_runtime_get_sync() will return 1, so a test for negative
> value should be used to check for errors.
>
> Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
> Signed-off-by: Miaoqian Lin <[email protected]>

Reviewed-by: Abel Vesa <[email protected]>

> ---
> drivers/clk/imx/clk-scu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
> index 083da31dc3ea..18c6190eeffd 100644
> --- a/drivers/clk/imx/clk-scu.c
> +++ b/drivers/clk/imx/clk-scu.c
> @@ -529,7 +529,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
> pm_runtime_enable(dev);
>
> ret = pm_runtime_get_sync(dev);
> - if (ret) {
> + if (ret < 0) {
> pm_genpd_remove_device(dev);
> pm_runtime_disable(dev);
> return ret;
> --
> 2.17.1
>

2022-04-22 18:31:51

by Miaoqian Lin

Subject: Re: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking

On 2022/4/22 9:20, Stephen Boyd wrote:
> Quoting Miaoqian Lin (2022-04-11 23:57:18)
>> If the device is already in a runtime PM enabled state
>> pm_runtime_get_sync() will return 1, so a test for negative
>> value should be used to check for errors.
> Maybe it should use pm_runtime_resume_and_get() instead?
Fair enough，I will send patch v2.
>> Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
>> Signed-off-by: Miaoqian Lin <[email protected]>
>> ---
>> drivers/clk/imx/clk-scu.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
>> index 083da31dc3ea..18c6190eeffd 100644
>> --- a/drivers/clk/imx/clk-scu.c
>> +++ b/drivers/clk/imx/clk-scu.c
>> @@ -529,7 +529,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
>> pm_runtime_enable(dev);
>>
>> ret = pm_runtime_get_sync(dev);
>> - if (ret) {
>> + if (ret < 0) {
>> pm_genpd_remove_device(dev);
>> pm_runtime_disable(dev);
>> return ret;
>> --
>> 2.17.1
>>

2022-04-22 19:59:23

by Stephen Boyd

Subject: Re: [PATCH] clk: imx: scu: Fix pm_runtime_get_sync() error checking

Quoting Miaoqian Lin (2022-04-11 23:57:18)
> If the device is already in a runtime PM enabled state
> pm_runtime_get_sync() will return 1, so a test for negative
> value should be used to check for errors.

Maybe it should use pm_runtime_resume_and_get() instead?

>
> Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
> Signed-off-by: Miaoqian Lin <[email protected]>
> ---
> drivers/clk/imx/clk-scu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
> index 083da31dc3ea..18c6190eeffd 100644
> --- a/drivers/clk/imx/clk-scu.c
> +++ b/drivers/clk/imx/clk-scu.c
> @@ -529,7 +529,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
> pm_runtime_enable(dev);
>
> ret = pm_runtime_get_sync(dev);
> - if (ret) {
> + if (ret < 0) {
> pm_genpd_remove_device(dev);
> pm_runtime_disable(dev);
> return ret;
> --
> 2.17.1
>

2022-04-22 22:55:53

by Miaoqian Lin

Subject: [PATCH v2] clk: imx: scu: Use pm_runtime_resume_and_get to fix pm_runtime_get_sync() usage

If the device is already in a runtime PM enabled state
pm_runtime_get_sync() will return 1.

Also, we need to call pm_runtime_put_noidle() when pm_runtime_get_sync()
fails, so use pm_runtime_resume_and_get() instead. this function
will handle this.

Fixes: 78edeb080330 ("clk: imx: scu: add runtime pm support")
Signed-off-by: Miaoqian Lin <[email protected]>
---
drivers/clk/imx/clk-scu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c
index 083da31dc3ea..2044e62980e3 100644
--- a/drivers/clk/imx/clk-scu.c
+++ b/drivers/clk/imx/clk-scu.c
@@ -528,7 +528,7 @@ static int imx_clk_scu_probe(struct platform_device *pdev)
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_enable(dev);

- ret = pm_runtime_get_sync(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret) {
pm_genpd_remove_device(dev);
pm_runtime_disable(dev);
--
2.17.1