2014-02-20 15:19:16

by Krzysztof Kozlowski

[permalink] [raw]
Subject: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
of_node_put). The DTS parsing function returned number of matched
regulators as success status which then was compared against 0 in probe.

Result was a probe fail after successful parsing the DTS:
max14577-regulator: probe of max14577-regulator failed with error 2

Signed-off-by: Krzysztof Kozlowski <[email protected]>
---
drivers/regulator/max14577.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
index 186df8785a91..6ba11a8dd23d 100644
--- a/drivers/regulator/max14577.c
+++ b/drivers/regulator/max14577.c
@@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
MAX14577_REG_MAX);
if (ret < 0) {
dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
+ of_node_put(np);
+ return ret;
}

of_node_put(np);

- return ret;
+ return 0;
}

static inline struct regulator_init_data *match_init_data(int index)
--
1.7.9.5


2014-02-21 10:24:40

by Sachin Kamat

[permalink] [raw]
Subject: Re: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

Hi Krzysztof,

On 20 February 2014 20:49, Krzysztof Kozlowski <[email protected]> wrote:
> This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
> of_node_put). The DTS parsing function returned number of matched
> regulators as success status which then was compared against 0 in probe.
>
> Result was a probe fail after successful parsing the DTS:
> max14577-regulator: probe of max14577-regulator failed with error 2
>
> Signed-off-by: Krzysztof Kozlowski <[email protected]>
> ---
> drivers/regulator/max14577.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
> index 186df8785a91..6ba11a8dd23d 100644
> --- a/drivers/regulator/max14577.c
> +++ b/drivers/regulator/max14577.c
> @@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
> MAX14577_REG_MAX);
> if (ret < 0) {
> dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> + of_node_put(np);
> + return ret;
> }
>
> of_node_put(np);
>
> - return ret;
> + return 0;
> }

Instead of so many changes here, you could simply make the following change
in the max14577_regulator_probe function.

ret = max14577_regulator_dt_parse_pdata(pdev);
if (ret < 0)
return ret;

--
With warm regards,
Sachin

2014-02-21 10:42:59

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

On Fri, 2014-02-21 at 15:54 +0530, Sachin Kamat wrote:
> Hi Krzysztof,
>
> On 20 February 2014 20:49, Krzysztof Kozlowski <[email protected]> wrote:
> > This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
> > of_node_put). The DTS parsing function returned number of matched
> > regulators as success status which then was compared against 0 in probe.
> >
> > Result was a probe fail after successful parsing the DTS:
> > max14577-regulator: probe of max14577-regulator failed with error 2
> >
> > Signed-off-by: Krzysztof Kozlowski <[email protected]>
> > ---
> > drivers/regulator/max14577.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
> > index 186df8785a91..6ba11a8dd23d 100644
> > --- a/drivers/regulator/max14577.c
> > +++ b/drivers/regulator/max14577.c
> > @@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
> > MAX14577_REG_MAX);
> > if (ret < 0) {
> > dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> > + of_node_put(np);
> > + return ret;
> > }
> >
> > of_node_put(np);
> >
> > - return ret;
> > + return 0;
> > }
>
> Instead of so many changes here, you could simply make the following change
> in the max14577_regulator_probe function.
>
> ret = max14577_regulator_dt_parse_pdata(pdev);
> if (ret < 0)
> return ret;

That still wouldn't be sufficient because later in probe() the 'ret' is
not reassigned (if devm_regulator_register succeeds) and it is directly
returned at the probe() end. So still the number of matched regulators
would be returned as probe result.

Best regards,
Krzysztof

2014-02-21 10:55:37

by Sachin Kamat

[permalink] [raw]
Subject: Re: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

On 21 February 2014 16:12, Krzysztof Kozlowski <[email protected]> wrote:
> On Fri, 2014-02-21 at 15:54 +0530, Sachin Kamat wrote:
>> Hi Krzysztof,
>>
>> On 20 February 2014 20:49, Krzysztof Kozlowski <[email protected]> wrote:
>> > This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
>> > of_node_put). The DTS parsing function returned number of matched
>> > regulators as success status which then was compared against 0 in probe.
>> >
>> > Result was a probe fail after successful parsing the DTS:
>> > max14577-regulator: probe of max14577-regulator failed with error 2
>> >
>> > Signed-off-by: Krzysztof Kozlowski <[email protected]>
>> > ---
>> > drivers/regulator/max14577.c | 4 +++-
>> > 1 file changed, 3 insertions(+), 1 deletion(-)
>> >
>> > diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
>> > index 186df8785a91..6ba11a8dd23d 100644
>> > --- a/drivers/regulator/max14577.c
>> > +++ b/drivers/regulator/max14577.c
>> > @@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
>> > MAX14577_REG_MAX);
>> > if (ret < 0) {
>> > dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
>> > + of_node_put(np);
>> > + return ret;
>> > }
>> >
>> > of_node_put(np);
>> >
>> > - return ret;
>> > + return 0;
>> > }
>>
>> Instead of so many changes here, you could simply make the following change
>> in the max14577_regulator_probe function.
>>
>> ret = max14577_regulator_dt_parse_pdata(pdev);
>> if (ret < 0)
>> return ret;
>
> That still wouldn't be sufficient because later in probe() the 'ret' is
> not reassigned (if devm_regulator_register succeeds) and it is directly
> returned at the probe() end. So still the number of matched regulators
> would be returned as probe result.

Ah, you are right. In that case how about the following:

- if (ret < 0) {
+ if (ret < 0)
dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
- }
+ else
+ ret = 0;

I am just trying to see if we can avoid any code duplication.
--
With warm regards,
Sachin

2014-02-21 11:14:26

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH] regulator: max14577: Fix invalid return value on DT parse success

On Fri, 2014-02-21 at 16:25 +0530, Sachin Kamat wrote:
> On 21 February 2014 16:12, Krzysztof Kozlowski <[email protected]> wrote:
> > On Fri, 2014-02-21 at 15:54 +0530, Sachin Kamat wrote:
> >> Hi Krzysztof,
> >>
> >> On 20 February 2014 20:49, Krzysztof Kozlowski <[email protected]> wrote:
> >> > This fixes bug introduced in 667a6b7a (regulator: max14577: Add missing
> >> > of_node_put). The DTS parsing function returned number of matched
> >> > regulators as success status which then was compared against 0 in probe.
> >> >
> >> > Result was a probe fail after successful parsing the DTS:
> >> > max14577-regulator: probe of max14577-regulator failed with error 2
> >> >
> >> > Signed-off-by: Krzysztof Kozlowski <[email protected]>
> >> > ---
> >> > drivers/regulator/max14577.c | 4 +++-
> >> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >> >
> >> > diff --git a/drivers/regulator/max14577.c b/drivers/regulator/max14577.c
> >> > index 186df8785a91..6ba11a8dd23d 100644
> >> > --- a/drivers/regulator/max14577.c
> >> > +++ b/drivers/regulator/max14577.c
> >> > @@ -168,11 +168,13 @@ static int max14577_regulator_dt_parse_pdata(struct platform_device *pdev)
> >> > MAX14577_REG_MAX);
> >> > if (ret < 0) {
> >> > dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> >> > + of_node_put(np);
> >> > + return ret;
> >> > }
> >> >
> >> > of_node_put(np);
> >> >
> >> > - return ret;
> >> > + return 0;
> >> > }
> >>
> >> Instead of so many changes here, you could simply make the following change
> >> in the max14577_regulator_probe function.
> >>
> >> ret = max14577_regulator_dt_parse_pdata(pdev);
> >> if (ret < 0)
> >> return ret;
> >
> > That still wouldn't be sufficient because later in probe() the 'ret' is
> > not reassigned (if devm_regulator_register succeeds) and it is directly
> > returned at the probe() end. So still the number of matched regulators
> > would be returned as probe result.
>
> Ah, you are right. In that case how about the following:
>
> - if (ret < 0) {
> + if (ret < 0)
> dev_err(&pdev->dev, "Error parsing regulator init data: %d\n", ret);
> - }
> + else
> + ret = 0;
>
> I am just trying to see if we can avoid any code duplication.

Looks good. Thanks for idea, I'll send v2.

Best regards,
Krzysztof