[PATCH -next] drivers/tty/serial: Add missing clk_disable_unprepare()

[PATCH -next] drivers/tty/serial: Add missing clk_disable_unprepare()

[Guo Mengqi]

Add missing clk_disable_unprepare() when get clk rate fails.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index 2a1226a78a0c..21939bb44613 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -166,8 +166,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	uartclk = clk_get_rate(data->clk);
 	if (!uartclk) {
 		ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk);
-		if (ret)
-			return dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+		if (ret) {
+			dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+			goto dis_clk;
+		}
 	}
 
 	/* the HW-clock divider for bcm2835aux is 8,
-- 
2.17.1

Re: [PATCH -next] drivers/tty/serial: Add missing clk_disable_unprepare()

[Greg KH]

On Fri, Jun 17, 2022 at 10:58:27AM +0800, Guo Mengqi wrote:
> Add missing clk_disable_unprepare() when get clk rate fails.
> 
> Reported-by: Hulk Robot <hulkci@huawei.com>

How did the robot report it?

How was this tested?

You have read the documentation for how to correctly report problems
found and fixed by automated tools, right?  Please update the changelog
to include all of that information.

thanks,

greg k-h

[PATCH -next v2] serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()

[Guo Mengqi]

The error path when get clock frequency fails in bcm2835aux_serial
driver does not correctly disable the clock.

This flaw was found using a static analysis tool "Hulk Robot", which
reported the following warning when analyzing linux-next/master:

    drivers/tty/serial/8250/8250_bcm2835aux.c:
    warning: clk_disable_unprepare_missing.cocci

The cocci script checks for the existence of clk_disable_unprepare()
paired with clk_prepare_enable().

Add the missing clk_disable_unprepare() to the error path.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>
---
v2:
- Change title to more standard format
- Add details about how Hulk Robot report this issue.
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index d9f1e618cfbd..f5718ff0cd8a 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -167,8 +167,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	uartclk = clk_get_rate(data->clk);
 	if (!uartclk) {
 		ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk);
-		if (ret)
-			return dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+		if (ret) {
+			dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+			goto dis_clk;
+		}
 	}
 
 	/* the HW-clock divider for bcm2835aux is 8,
-- 
2.17.1

Re: [PATCH -next] drivers/tty/serial: Add missing clk_disable_unprepare()

[Florian Fainelli]

On 6/16/2022 7:58 PM, 'Guo Mengqi' via BCM-KERNEL-FEEDBACK-LIST,PDL wrote:
> Add missing clk_disable_unprepare() when get clk rate fails.
> 
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>

Looks about right, can we use the same prefix as the majority of other 
changes:

serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()

and slap a:

Fixes: fcc446c8aa63 ("serial: 8250_bcm2835aux: Add ACPI support")

Thanks!

> ---
>   drivers/tty/serial/8250/8250_bcm2835aux.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
> index 2a1226a78a0c..21939bb44613 100644
> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
> @@ -166,8 +166,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
>   	uartclk = clk_get_rate(data->clk);
>   	if (!uartclk) {
>   		ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk);
> -		if (ret)
> -			return dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
> +		if (ret) {
> +			dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
> +			goto dis_clk;
> +		}
>   	}
>   
>   	/* the HW-clock divider for bcm2835aux is 8,

-- 
Florian

Re: [PATCH -next] drivers/tty/serial: Add missing clk_disable_unprepare()

[guomengqi (A)]

Hi Florian,

Yes I found it's better to use title of same style. I did not pay 
attention to this.

I will send a new version of this patch.

Thank you!

在 2022/7/12 11:35, Florian Fainelli 写道:
>
>
> On 6/16/2022 7:58 PM, 'Guo Mengqi' via BCM-KERNEL-FEEDBACK-LIST,PDL 
> wrote:
>> Add missing clk_disable_unprepare() when get clk rate fails.
>>
>> Reported-by: Hulk Robot <hulkci@huawei.com>
>> Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>
>
> Looks about right, can we use the same prefix as the majority of other 
> changes:
>
> serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()
>
> and slap a:
>
> Fixes: fcc446c8aa63 ("serial: 8250_bcm2835aux: Add ACPI support")
>
> Thanks!
>
>> ---
>>   drivers/tty/serial/8250/8250_bcm2835aux.c | 6 ++++--
>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c 
>> b/drivers/tty/serial/8250/8250_bcm2835aux.c
>> index 2a1226a78a0c..21939bb44613 100644
>> --- a/drivers/tty/serial/8250/8250_bcm2835aux.c
>> +++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
>> @@ -166,8 +166,10 @@ static int bcm2835aux_serial_probe(struct 
>> platform_device *pdev)
>>       uartclk = clk_get_rate(data->clk);
>>       if (!uartclk) {
>>           ret = device_property_read_u32(&pdev->dev, 
>> "clock-frequency", &uartclk);
>> -        if (ret)
>> -            return dev_err_probe(&pdev->dev, ret, "could not get clk 
>> rate\n");
>> +        if (ret) {
>> +            dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
>> +            goto dis_clk;
>> +        }
>>       }
>>         /* the HW-clock divider for bcm2835aux is 8,
>

[PATCH -next v3] serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()

[Guo Mengqi]

The error path when get clock frequency fails in bcm2835aux_serial
driver does not correctly disable the clock.

This flaw was found using a static analysis tool "Hulk Robot", which
reported the following warning when analyzing linux-next/master:

    drivers/tty/serial/8250/8250_bcm2835aux.c:
    warning: clk_disable_unprepare_missing.cocci

The cocci script checks for the existence of clk_disable_unprepare()
paired with clk_prepare_enable().

Add the missing clk_disable_unprepare() to the error path.

Fixes: fcc446c8aa63 ("serial: 8250_bcm2835aux: Add ACPI support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>
---
v2:
- Change title to more standard format
- Add details about how Hulk Robot report this issue.
v3:
- add which commit this patch fixes
---
 drivers/tty/serial/8250/8250_bcm2835aux.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_bcm2835aux.c b/drivers/tty/serial/8250/8250_bcm2835aux.c
index 047e14ccb165..15a2387a5b25 100644
--- a/drivers/tty/serial/8250/8250_bcm2835aux.c
+++ b/drivers/tty/serial/8250/8250_bcm2835aux.c
@@ -167,8 +167,10 @@ static int bcm2835aux_serial_probe(struct platform_device *pdev)
 	uartclk = clk_get_rate(data->clk);
 	if (!uartclk) {
 		ret = device_property_read_u32(&pdev->dev, "clock-frequency", &uartclk);
-		if (ret)
-			return dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+		if (ret) {
+			dev_err_probe(&pdev->dev, ret, "could not get clk rate\n");
+			goto dis_clk;
+		}
 	}
 
 	/* the HW-clock divider for bcm2835aux is 8,
-- 
2.17.1

Re: [PATCH -next v3] serial: 8250_bcm2835aux: Add missing clk_disable_unprepare()

[Florian Fainelli]

On 7/14/2022 7:33 PM, Guo Mengqi wrote:
> The error path when get clock frequency fails in bcm2835aux_serial
> driver does not correctly disable the clock.
> 
> This flaw was found using a static analysis tool "Hulk Robot", which
> reported the following warning when analyzing linux-next/master:
> 
>      drivers/tty/serial/8250/8250_bcm2835aux.c:
>      warning: clk_disable_unprepare_missing.cocci
> 
> The cocci script checks for the existence of clk_disable_unprepare()
> paired with clk_prepare_enable().
> 
> Add the missing clk_disable_unprepare() to the error path.
> 
> Fixes: fcc446c8aa63 ("serial: 8250_bcm2835aux: Add ACPI support")
> Reported-by: Hulk Robot <hulkci@huawei.com>
> Signed-off-by: Guo Mengqi <guomengqi3@huawei.com>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian