Mailing List Archive: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get

[PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage()

Mar 27, 2024, 4:18 PM

Post #1 of 4 (9 views)

We can reduce boilerplate code by using
devm_regulator_get_enable_get_voltage().

Signed-off-by: David Lechner <dlechner@baylibre.com>
---
drivers/hwmon/da9052-hwmon.c | 33 +++++++--------------------------
1 file changed, 7 insertions(+), 26 deletions(-)

diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
index 2bd7ae8100d7..70e7bc72e980 100644
--- a/drivers/hwmon/da9052-hwmon.c
+++ b/drivers/hwmon/da9052-hwmon.c
@@ -26,7 +26,6 @@ struct da9052_hwmon {
struct mutex hwmon_lock;
bool tsi_as_adc;
int tsiref_mv;
- struct regulator *tsiref;
struct completion tsidone;
};

@@ -414,32 +413,19 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");

if (hwmon->tsi_as_adc) {
- hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
- if (IS_ERR(hwmon->tsiref)) {
- err = PTR_ERR(hwmon->tsiref);
- dev_err(&pdev->dev, "failed to get tsiref: %d", err);
+ err = devm_regulator_get_enable_get_voltage(pdev->dev.parent,
+ "tsiref");
+ if (err < 0)
return err;
- }
-
- err = regulator_enable(hwmon->tsiref);
- if (err)
- return err;
-
- hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
- if (hwmon->tsiref_mv < 0) {
- err = hwmon->tsiref_mv;
- goto exit_regulator;
- }

/* convert from microvolt (DT) to millivolt (hwmon) */
- hwmon->tsiref_mv /= 1000;
+ hwmon->tsiref_mv = err / 1000;

/* TSIREF limits from datasheet */
if (hwmon->tsiref_mv < 1800 || hwmon->tsiref_mv > 2600) {
dev_err(hwmon->da9052->dev, "invalid TSIREF voltage: %d",
hwmon->tsiref_mv);
- err = -ENXIO;
- goto exit_regulator;
+ return -ENXIO;
}

/* disable touchscreen features */
@@ -456,7 +442,7 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
if (err) {
dev_err(&pdev->dev, "Failed to register TSIRDY IRQ: %d",
err);
- goto exit_regulator;
+ return err;
}
}

@@ -472,9 +458,6 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
exit_irq:
if (hwmon->tsi_as_adc)
da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
-exit_regulator:
- if (hwmon->tsiref)
- regulator_disable(hwmon->tsiref);

return err;
}
@@ -483,10 +466,8 @@ static void da9052_hwmon_remove(struct platform_device *pdev)
{
struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);

- if (hwmon->tsi_as_adc) {
+ if (hwmon->tsi_as_adc)
da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
- regulator_disable(hwmon->tsiref);
- }
}

static struct platform_driver da9052_hwmon_driver = {

--
2.43.2

Re: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage() [ In reply to ]

jic23 at kernel

Mar 28, 2024, 7:20 AM

Post #2 of 4 (9 views)

Permalink

On Wed, 27 Mar 2024 18:18:52 -0500
David Lechner <dlechner@baylibre.com> wrote:

> We can reduce boilerplate code by using
> devm_regulator_get_enable_get_voltage().
>
> Signed-off-by: David Lechner <dlechner@baylibre.com>

A few comments inline, but nothing substantial.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
> drivers/hwmon/da9052-hwmon.c | 33 +++++++--------------------------
> 1 file changed, 7 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
> index 2bd7ae8100d7..70e7bc72e980 100644
> --- a/drivers/hwmon/da9052-hwmon.c
> +++ b/drivers/hwmon/da9052-hwmon.c
> @@ -26,7 +26,6 @@ struct da9052_hwmon {
> struct mutex hwmon_lock;
> bool tsi_as_adc;
> int tsiref_mv;
> - struct regulator *tsiref;
> struct completion tsidone;
> };
>
> @@ -414,32 +413,19 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
> device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");
>
> if (hwmon->tsi_as_adc) {
> - hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
> - if (IS_ERR(hwmon->tsiref)) {
> - err = PTR_ERR(hwmon->tsiref);
> - dev_err(&pdev->dev, "failed to get tsiref: %d", err);
> + err = devm_regulator_get_enable_get_voltage(pdev->dev.parent,
> + "tsiref");
> + if (err < 0)
> return err;
> - }
> -
> - err = regulator_enable(hwmon->tsiref);
> - if (err)
> - return err;
> -
> - hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
> - if (hwmon->tsiref_mv < 0) {
> - err = hwmon->tsiref_mv;
> - goto exit_regulator;
> - }
>
> /* convert from microvolt (DT) to millivolt (hwmon) */
> - hwmon->tsiref_mv /= 1000;
> + hwmon->tsiref_mv = err / 1000;
>

Using a variable called err for a good value is a bit ugly but fair enough if that
is precedence in this driver.

> }
> @@ -483,10 +466,8 @@ static void da9052_hwmon_remove(struct platform_device *pdev)
> {
> struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
>
> - if (hwmon->tsi_as_adc) {
> + if (hwmon->tsi_as_adc)
> da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
Superficially looks like devm_da9052_request_irq could be added that
uses devm_request_threaded_irq() to allow dropping this remaining handling.

Thanks,

Jonathan

> - regulator_disable(hwmon->tsiref);
> - }
> }
>
> static struct platform_driver da9052_hwmon_driver = {
>

Re: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage() [ In reply to ]

linux at roeck-us

Mar 28, 2024, 8:20 AM

Post #3 of 4 (9 views)

Permalink

On 3/28/24 07:20, Jonathan Cameron wrote:
> On Wed, 27 Mar 2024 18:18:52 -0500
> David Lechner <dlechner@baylibre.com> wrote:
>
>> We can reduce boilerplate code by using
>> devm_regulator_get_enable_get_voltage().
>>
>> Signed-off-by: David Lechner <dlechner@baylibre.com>
>
> A few comments inline, but nothing substantial.
>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> ---
>> drivers/hwmon/da9052-hwmon.c | 33 +++++++--------------------------
>> 1 file changed, 7 insertions(+), 26 deletions(-)
>>
>> diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
>> index 2bd7ae8100d7..70e7bc72e980 100644
>> --- a/drivers/hwmon/da9052-hwmon.c
>> +++ b/drivers/hwmon/da9052-hwmon.c
>> @@ -26,7 +26,6 @@ struct da9052_hwmon {
>> struct mutex hwmon_lock;
>> bool tsi_as_adc;
>> int tsiref_mv;
>> - struct regulator *tsiref;
>> struct completion tsidone;
>> };
>>
>> @@ -414,32 +413,19 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
>> device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");
>>
>> if (hwmon->tsi_as_adc) {
>> - hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
>> - if (IS_ERR(hwmon->tsiref)) {
>> - err = PTR_ERR(hwmon->tsiref);
>> - dev_err(&pdev->dev, "failed to get tsiref: %d", err);
>> + err = devm_regulator_get_enable_get_voltage(pdev->dev.parent,
>> + "tsiref");
>> + if (err < 0)
>> return err;
>> - }
>> -
>> - err = regulator_enable(hwmon->tsiref);
>> - if (err)
>> - return err;
>> -
>> - hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
>> - if (hwmon->tsiref_mv < 0) {
>> - err = hwmon->tsiref_mv;
>> - goto exit_regulator;
>> - }
>>
>> /* convert from microvolt (DT) to millivolt (hwmon) */
>> - hwmon->tsiref_mv /= 1000;
>> + hwmon->tsiref_mv = err / 1000;
>>
>
> Using a variable called err for a good value is a bit ugly but fair enough if that
> is precedence in this driver.
>

It isn't. The existing code assigns the return value from regulator_get_voltage()
to hwmon->tsiref_mv and then evaluates it. I would not oppose introducing a variable
such as tsiref_uv, but not the misuse of 'err'. I am not going to accept the code
as suggested. It is bad style, and it would invite others to use it as precedent
when trying to introduce similar code.

>> }
>> @@ -483,10 +466,8 @@ static void da9052_hwmon_remove(struct platform_device *pdev)
>> {
>> struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
>>
>> - if (hwmon->tsi_as_adc) {
>> + if (hwmon->tsi_as_adc)
>> da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
> Superficially looks like devm_da9052_request_irq could be added that
> uses devm_request_threaded_irq() to allow dropping this remaining handling.
>

That should be a separate series of patches. A local solution might be
to use devm_add_action_or_reset(), but that should also be a separate patch.

Thanks,
Guenter

Re: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage() [ In reply to ]

jic23 at kernel

Mar 28, 2024, 8:53 AM

Post #4 of 4 (9 views)

Permalink

On Thu, 28 Mar 2024 08:20:00 -0700
Guenter Roeck <linux@roeck-us.net> wrote:

> On 3/28/24 07:20, Jonathan Cameron wrote:
> > On Wed, 27 Mar 2024 18:18:52 -0500
> > David Lechner <dlechner@baylibre.com> wrote:
> >
> >> We can reduce boilerplate code by using
> >> devm_regulator_get_enable_get_voltage().
> >>
> >> Signed-off-by: David Lechner <dlechner@baylibre.com>
> >
> > A few comments inline, but nothing substantial.
> >
> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> >> ---
> >> drivers/hwmon/da9052-hwmon.c | 33 +++++++--------------------------
> >> 1 file changed, 7 insertions(+), 26 deletions(-)
> >>
> >> diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
> >> index 2bd7ae8100d7..70e7bc72e980 100644
> >> --- a/drivers/hwmon/da9052-hwmon.c
> >> +++ b/drivers/hwmon/da9052-hwmon.c
> >> @@ -26,7 +26,6 @@ struct da9052_hwmon {
> >> struct mutex hwmon_lock;
> >> bool tsi_as_adc;
> >> int tsiref_mv;
> >> - struct regulator *tsiref;
> >> struct completion tsidone;
> >> };
> >>
> >> @@ -414,32 +413,19 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
> >> device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");
> >>
> >> if (hwmon->tsi_as_adc) {
> >> - hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
> >> - if (IS_ERR(hwmon->tsiref)) {
> >> - err = PTR_ERR(hwmon->tsiref);
> >> - dev_err(&pdev->dev, "failed to get tsiref: %d", err);
> >> + err = devm_regulator_get_enable_get_voltage(pdev->dev.parent,
> >> + "tsiref");
> >> + if (err < 0)
> >> return err;
> >> - }
> >> -
> >> - err = regulator_enable(hwmon->tsiref);
> >> - if (err)
> >> - return err;
> >> -
> >> - hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
> >> - if (hwmon->tsiref_mv < 0) {
> >> - err = hwmon->tsiref_mv;
> >> - goto exit_regulator;
> >> - }
> >>
> >> /* convert from microvolt (DT) to millivolt (hwmon) */
> >> - hwmon->tsiref_mv /= 1000;
> >> + hwmon->tsiref_mv = err / 1000;
> >>
> >
> > Using a variable called err for a good value is a bit ugly but fair enough if that
> > is precedence in this driver.
> >
>
> It isn't. The existing code assigns the return value from regulator_get_voltage()
> to hwmon->tsiref_mv and then evaluates it. I would not oppose introducing a variable
> such as tsiref_uv, but not the misuse of 'err'. I am not going to accept the code
> as suggested. It is bad style, and it would invite others to use it as precedent
> when trying to introduce similar code.

I was too lazy to look and see if there were existing cases :) Local variable indeed
the right way to go.

>
> >> }
> >> @@ -483,10 +466,8 @@ static void da9052_hwmon_remove(struct platform_device *pdev)
> >> {
> >> struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
> >>
> >> - if (hwmon->tsi_as_adc) {
> >> + if (hwmon->tsi_as_adc)
> >> da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
> > Superficially looks like devm_da9052_request_irq could be added that
> > uses devm_request_threaded_irq() to allow dropping this remaining handling.
> >
>
> That should be a separate series of patches. A local solution might be
> to use devm_add_action_or_reset(), but that should also be a separate patch.

Agreed. Just a passing comment whilst the code was in front of me.

Jonathan

>
> Thanks,
> Guenter
>