[PATCH v3 00/14] Use devm helpers for regulator get and enable

[PATCH v3 00/14] Use devm helpers for regulator get and enable

[Matti Vaittinen]

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Use devm helpers for regulator get and enable

NOTE: The series depends on commit
ee94aff2628b ("Devm helpers for regulator get and enable")
which currently sits in Mark's regulator/for-next

A few* drivers seem to pattern demonstrated by pseudocode:

- devm_regulator_get()
- regulator_enable()
- devm_add_action_or_reset(regulator_disable())

devm helpers for this pattern were added to remove bunch of code from
drivers. Typically following:

- replace 3 calls (devm_regulator_get[_optional](), regulator_enable(),
  devm_add_action_or_reset()) with just one
  (devm_regulator_get_enable[_optional]()).
- drop disable callback.

I believe this simplifies things by removing some dublicated code.

This series reowrks a few drivers. There is still plenty of fish in the
sea for people who like to improve the code (or count the beans ;]).

Finally - most of the converted drivers have not been tested (other than
compile-tested) due to lack of HW. All reviews and testing is _highly_
appreciated (as always!).

Revision history:

v3:
	- Drop already applied helper patches
	- Add a few more drivers

RFCv1 => v2:
	- Add devm_regulator_bulk_get_enable() and
	  devm_regulator_bulk_put()
	- Convert a couple of drivers to use the new
	  devm_regulator_bulk_get_enable().
	- Squash all IIO patches into one.

Patch 1:
	Add new devm-helper APIs to docs.
Patch 2:
	simplified CLK driver(s)
Patch 3:
	simplified GPU driver(s)
Patch 4 - 5:
	simplified hwmon driver(s)
Patch 6 - 14:
	simplified IIO driver(s)

---

Matti Vaittinen (14):
  docs: devres: regulator: Add new get_enable functions to devres.rst
  clk: cdce925: simplify using devm_regulator_get_enable()
  gpu: drm: simplify drivers using devm_regulator_*get_enable*()
  hwmon: lm90: simplify using devm_regulator_get_enable()
  hwmon: adm1177: simplify using devm_regulator_get_enable()
  iio: ad7192: Simplify using devm_regulator_get_enable()
  iio: ltc2688: Simplify using devm_regulator_*get_enable()
  iio: bmg160_core: Simplify using devm_regulator_*get_enable()
  iio: st_lsm6dsx: Simplify using devm_regulator_*get_enable()
  iio: ad7476: simplify using devm_regulator_get_enable()
  iio: ad7606: simplify using devm_regulator_get_enable()
  iio: max1241: simplify using devm_regulator_get_enable()
  iio: max1363: simplify using devm_regulator_get_enable()
  iio: hmc425a: simplify using devm_regulator_get_enable()

 .../driver-api/driver-model/devres.rst        |  4 +++
 drivers/clk/clk-cdce925.c                     | 21 +++----------
 drivers/gpu/drm/bridge/sii902x.c              | 22 ++------------
 drivers/gpu/drm/meson/meson_dw_hdmi.c         | 23 ++------------
 drivers/hwmon/adm1177.c                       | 27 ++---------------
 drivers/hwmon/lm90.c                          | 15 ++--------
 drivers/iio/adc/ad7192.c                      | 15 ++--------
 drivers/iio/adc/ad7476.c                      | 11 +------
 drivers/iio/adc/ad7606.c                      | 22 ++------------
 drivers/iio/adc/ad7606.h                      |  1 -
 drivers/iio/adc/max1241.c                     | 28 ++---------------
 drivers/iio/adc/max1363.c                     | 11 +------
 drivers/iio/amplifiers/hmc425a.c              | 17 +----------
 drivers/iio/dac/ltc2688.c                     | 23 ++------------
 drivers/iio/gyro/bmg160_core.c                | 24 ++-------------
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h       |  2 --
 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c  | 30 ++++---------------
 17 files changed, 41 insertions(+), 255 deletions(-)

-- 
2.37.1


-- 
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =] 

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[PATCH v3 03/14] gpu: drm: simplify drivers using devm_regulator_*get_enable*()

[Matti Vaittinen]

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Simplify drivers using managed "regulator get and enable".

meson:
Use the devm_regulator_get_enable_optional(). Also drop the seemingly
unused struct member 'hdmi_supply'.

sii902x:
Simplify using devm_regulator_bulk_get_enable()

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>

---
v2 => v3:
No changes

RFCv1 => v2:
- Change also sii902x to use devm_regulator_bulk_get_enable()

Please note - this is only compile-tested due to the lack of HW. Careful
review and testing is _highly_ appreciated.
---
 drivers/gpu/drm/bridge/sii902x.c      | 22 +++-------------------
 drivers/gpu/drm/meson/meson_dw_hdmi.c | 23 +++--------------------
 2 files changed, 6 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
index 7ab38d734ad6..162f9c87eeb2 100644
--- a/drivers/gpu/drm/bridge/sii902x.c
+++ b/drivers/gpu/drm/bridge/sii902x.c
@@ -171,7 +171,6 @@ struct sii902x {
 	struct drm_connector connector;
 	struct gpio_desc *reset_gpio;
 	struct i2c_mux_core *i2cmux;
-	struct regulator_bulk_data supplies[2];
 	bool sink_is_hdmi;
 	/*
 	 * Mutex protects audio and video functions from interfering
@@ -1072,6 +1071,7 @@ static int sii902x_probe(struct i2c_client *client,
 	struct device *dev = &client->dev;
 	struct device_node *endpoint;
 	struct sii902x *sii902x;
+	static const char * const supplies[] = {"iovcc", "cvcc12"};
 	int ret;
 
 	ret = i2c_check_functionality(client->adapter,
@@ -1122,27 +1122,13 @@ static int sii902x_probe(struct i2c_client *client,
 
 	mutex_init(&sii902x->mutex);
 
-	sii902x->supplies[0].supply = "iovcc";
-	sii902x->supplies[1].supply = "cvcc12";
-	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(sii902x->supplies),
-				      sii902x->supplies);
-	if (ret < 0)
-		return ret;
-
-	ret = regulator_bulk_enable(ARRAY_SIZE(sii902x->supplies),
-				    sii902x->supplies);
+	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(supplies), supplies);
 	if (ret < 0) {
 		dev_err_probe(dev, ret, "Failed to enable supplies");
 		return ret;
 	}
 
-	ret = sii902x_init(sii902x);
-	if (ret < 0) {
-		regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
-				       sii902x->supplies);
-	}
-
-	return ret;
+	return sii902x_init(sii902x);
 }
 
 static int sii902x_remove(struct i2c_client *client)
@@ -1152,8 +1138,6 @@ static int sii902x_remove(struct i2c_client *client)
 
 	i2c_mux_del_adapters(sii902x->i2cmux);
 	drm_bridge_remove(&sii902x->bridge);
-	regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
-			       sii902x->supplies);
 
 	return 0;
 }
diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
index 5cd2b2ebbbd3..7642f740272b 100644
--- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
@@ -140,7 +140,6 @@ struct meson_dw_hdmi {
 	struct reset_control *hdmitx_apb;
 	struct reset_control *hdmitx_ctrl;
 	struct reset_control *hdmitx_phy;
-	struct regulator *hdmi_supply;
 	u32 irq_stat;
 	struct dw_hdmi *hdmi;
 	struct drm_bridge *bridge;
@@ -665,11 +664,6 @@ static void meson_dw_hdmi_init(struct meson_dw_hdmi *meson_dw_hdmi)
 
 }
 
-static void meson_disable_regulator(void *data)
-{
-	regulator_disable(data);
-}
-
 static void meson_disable_clk(void *data)
 {
 	clk_disable_unprepare(data);
@@ -723,20 +717,9 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
 	meson_dw_hdmi->data = match;
 	dw_plat_data = &meson_dw_hdmi->dw_plat_data;
 
-	meson_dw_hdmi->hdmi_supply = devm_regulator_get_optional(dev, "hdmi");
-	if (IS_ERR(meson_dw_hdmi->hdmi_supply)) {
-		if (PTR_ERR(meson_dw_hdmi->hdmi_supply) == -EPROBE_DEFER)
-			return -EPROBE_DEFER;
-		meson_dw_hdmi->hdmi_supply = NULL;
-	} else {
-		ret = regulator_enable(meson_dw_hdmi->hdmi_supply);
-		if (ret)
-			return ret;
-		ret = devm_add_action_or_reset(dev, meson_disable_regulator,
-					       meson_dw_hdmi->hdmi_supply);
-		if (ret)
-			return ret;
-	}
+	ret = devm_regulator_get_enable_optional(dev, "hdmi");
+	if (ret != -ENODEV)
+		return ret;
 
 	meson_dw_hdmi->hdmitx_apb = devm_reset_control_get_exclusive(dev,
 						"hdmitx_apb");
-- 
2.37.1


-- 
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =] 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

Re: [PATCH v3 00/14] Use devm helpers for regulator get and enable

[Andy Shevchenko]

On Fri, Aug 19, 2022 at 10:20 PM Matti Vaittinen
<mazziesaccount@gmail.com> wrote:
>
> Use devm helpers for regulator get and enable
>
> NOTE: The series depends on commit
> ee94aff2628b ("Devm helpers for regulator get and enable")
> which currently sits in Mark's regulator/for-next
>
> A few* drivers seem to pattern demonstrated by pseudocode:
>
> - devm_regulator_get()
> - regulator_enable()
> - devm_add_action_or_reset(regulator_disable())
>
> devm helpers for this pattern were added to remove bunch of code from

remove a bunch

> drivers. Typically following:
>
> - replace 3 calls (devm_regulator_get[_optional](), regulator_enable(),
>   devm_add_action_or_reset()) with just one
>   (devm_regulator_get_enable[_optional]()).
> - drop disable callback.
>
> I believe this simplifies things by removing some dublicated code.

duplicated

> This series reowrks a few drivers. There is still plenty of fish in the

reworks

> sea for people who like to improve the code (or count the beans ;]).
>
> Finally - most of the converted drivers have not been tested (other than
> compile-tested) due to lack of HW. All reviews and testing is _highly_
> appreciated (as always!).

...

>   docs: devres: regulator: Add new get_enable functions to devres.rst
>   clk: cdce925: simplify using devm_regulator_get_enable()
>   gpu: drm: simplify drivers using devm_regulator_*get_enable*()
>   hwmon: lm90: simplify using devm_regulator_get_enable()
>   hwmon: adm1177: simplify using devm_regulator_get_enable()

hwmon uses a different pattern for the Subject line.

-- 
With Best Regards,
Andy Shevchenko

Re: (subset) [PATCH v3 00/14] Use devm helpers for regulator get and enable

[Mark Brown]

On Fri, 19 Aug 2022 22:16:48 +0300, Matti Vaittinen wrote:
> Use devm helpers for regulator get and enable
> 
> NOTE: The series depends on commit
> ee94aff2628b ("Devm helpers for regulator get and enable")
> which currently sits in Mark's regulator/for-next
> 
> A few* drivers seem to pattern demonstrated by pseudocode:
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[01/14] docs: devres: regulator: Add new get_enable functions to devres.rst
        commit: 9048b9912f767ea9609e520678def446af804771

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Re: [PATCH v3 03/14] gpu: drm: simplify drivers using devm_regulator_*get_enable*()

[Robert Foss]

Hi Matti,

On Fri, 19 Aug 2022 at 21:18, Matti Vaittinen <mazziesaccount@gmail.com> wrote:
>
> Simplify drivers using managed "regulator get and enable".
>
> meson:
> Use the devm_regulator_get_enable_optional(). Also drop the seemingly
> unused struct member 'hdmi_supply'.
>
> sii902x:
> Simplify using devm_regulator_bulk_get_enable()
>
> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
>
> ---
> v2 => v3:
> No changes
>
> RFCv1 => v2:
> - Change also sii902x to use devm_regulator_bulk_get_enable()
>
> Please note - this is only compile-tested due to the lack of HW. Careful
> review and testing is _highly_ appreciated.
> ---
>  drivers/gpu/drm/bridge/sii902x.c      | 22 +++-------------------
>  drivers/gpu/drm/meson/meson_dw_hdmi.c | 23 +++--------------------
>  2 files changed, 6 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
> index 7ab38d734ad6..162f9c87eeb2 100644
> --- a/drivers/gpu/drm/bridge/sii902x.c
> +++ b/drivers/gpu/drm/bridge/sii902x.c
> @@ -171,7 +171,6 @@ struct sii902x {
>         struct drm_connector connector;
>         struct gpio_desc *reset_gpio;
>         struct i2c_mux_core *i2cmux;
> -       struct regulator_bulk_data supplies[2];
>         bool sink_is_hdmi;
>         /*
>          * Mutex protects audio and video functions from interfering
> @@ -1072,6 +1071,7 @@ static int sii902x_probe(struct i2c_client *client,
>         struct device *dev = &client->dev;
>         struct device_node *endpoint;
>         struct sii902x *sii902x;
> +       static const char * const supplies[] = {"iovcc", "cvcc12"};
>         int ret;
>
>         ret = i2c_check_functionality(client->adapter,
> @@ -1122,27 +1122,13 @@ static int sii902x_probe(struct i2c_client *client,
>
>         mutex_init(&sii902x->mutex);
>
> -       sii902x->supplies[0].supply = "iovcc";
> -       sii902x->supplies[1].supply = "cvcc12";
> -       ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(sii902x->supplies),
> -                                     sii902x->supplies);
> -       if (ret < 0)
> -               return ret;
> -
> -       ret = regulator_bulk_enable(ARRAY_SIZE(sii902x->supplies),
> -                                   sii902x->supplies);
> +       ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(supplies), supplies);
>         if (ret < 0) {
>                 dev_err_probe(dev, ret, "Failed to enable supplies");
>                 return ret;
>         }
>
> -       ret = sii902x_init(sii902x);
> -       if (ret < 0) {
> -               regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
> -                                      sii902x->supplies);
> -       }
> -
> -       return ret;
> +       return sii902x_init(sii902x);
>  }
>
>  static int sii902x_remove(struct i2c_client *client)
> @@ -1152,8 +1138,6 @@ static int sii902x_remove(struct i2c_client *client)
>
>         i2c_mux_del_adapters(sii902x->i2cmux);
>         drm_bridge_remove(&sii902x->bridge);
> -       regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
> -                              sii902x->supplies);
>
>         return 0;
>  }

Ideally this patch would be split into two parts here, due to
maintainership boundaries.

For the sii902x part, please add my r-b.

Reviewed-by: Robert Foss <robert.foss@linaro.org>

> diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> index 5cd2b2ebbbd3..7642f740272b 100644
> --- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
> +++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> @@ -140,7 +140,6 @@ struct meson_dw_hdmi {
>         struct reset_control *hdmitx_apb;
>         struct reset_control *hdmitx_ctrl;
>         struct reset_control *hdmitx_phy;
> -       struct regulator *hdmi_supply;
>         u32 irq_stat;
>         struct dw_hdmi *hdmi;
>         struct drm_bridge *bridge;
> @@ -665,11 +664,6 @@ static void meson_dw_hdmi_init(struct meson_dw_hdmi *meson_dw_hdmi)
>
>  }
>
> -static void meson_disable_regulator(void *data)
> -{
> -       regulator_disable(data);
> -}
> -
>  static void meson_disable_clk(void *data)
>  {
>         clk_disable_unprepare(data);
> @@ -723,20 +717,9 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
>         meson_dw_hdmi->data = match;
>         dw_plat_data = &meson_dw_hdmi->dw_plat_data;
>
> -       meson_dw_hdmi->hdmi_supply = devm_regulator_get_optional(dev, "hdmi");
> -       if (IS_ERR(meson_dw_hdmi->hdmi_supply)) {
> -               if (PTR_ERR(meson_dw_hdmi->hdmi_supply) == -EPROBE_DEFER)
> -                       return -EPROBE_DEFER;
> -               meson_dw_hdmi->hdmi_supply = NULL;
> -       } else {
> -               ret = regulator_enable(meson_dw_hdmi->hdmi_supply);
> -               if (ret)
> -                       return ret;
> -               ret = devm_add_action_or_reset(dev, meson_disable_regulator,
> -                                              meson_dw_hdmi->hdmi_supply);
> -               if (ret)
> -                       return ret;
> -       }
> +       ret = devm_regulator_get_enable_optional(dev, "hdmi");
> +       if (ret != -ENODEV)
> +               return ret;
>
>         meson_dw_hdmi->hdmitx_apb = devm_reset_control_get_exclusive(dev,
>                                                 "hdmitx_apb");
> --
> 2.37.1

Re: [PATCH v3 03/14] gpu: drm: simplify drivers using devm_regulator_*get_enable*()

[Matti Vaittinen]

On 8/29/22 17:25, Robert Foss wrote:

Thanks for the review Robert.

> Hi Matti,
> 
> On Fri, 19 Aug 2022 at 21:18, Matti Vaittinen <mazziesaccount@gmail.com> wrote:
>>
>> Simplify drivers using managed "regulator get and enable".
>>
>> meson:
>> Use the devm_regulator_get_enable_optional(). Also drop the seemingly
>> unused struct member 'hdmi_supply'.
>>
>> sii902x:
>> Simplify using devm_regulator_bulk_get_enable()
>>
>> Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
>>
>> ---
>> v2 => v3:
>> No changes
>>
>> RFCv1 => v2:
>> - Change also sii902x to use devm_regulator_bulk_get_enable()
>>
>> Please note - this is only compile-tested due to the lack of HW. Careful
>> review and testing is _highly_ appreciated.
>> ---
>>   drivers/gpu/drm/bridge/sii902x.c      | 22 +++-------------------
>>   drivers/gpu/drm/meson/meson_dw_hdmi.c | 23 +++--------------------
>>   2 files changed, 6 insertions(+), 39 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/sii902x.c b/drivers/gpu/drm/bridge/sii902x.c
>> index 7ab38d734ad6..162f9c87eeb2 100644
>> --- a/drivers/gpu/drm/bridge/sii902x.c
>> +++ b/drivers/gpu/drm/bridge/sii902x.c
>> @@ -171,7 +171,6 @@ struct sii902x {
>>          struct drm_connector connector;
>>          struct gpio_desc *reset_gpio;
>>          struct i2c_mux_core *i2cmux;
>> -       struct regulator_bulk_data supplies[2];
>>          bool sink_is_hdmi;
>>          /*
>>           * Mutex protects audio and video functions from interfering
>> @@ -1072,6 +1071,7 @@ static int sii902x_probe(struct i2c_client *client,
>>          struct device *dev = &client->dev;
>>          struct device_node *endpoint;
>>          struct sii902x *sii902x;
>> +       static const char * const supplies[] = {"iovcc", "cvcc12"};
>>          int ret;
>>
>>          ret = i2c_check_functionality(client->adapter,
>> @@ -1122,27 +1122,13 @@ static int sii902x_probe(struct i2c_client *client,
>>
>>          mutex_init(&sii902x->mutex);
>>
>> -       sii902x->supplies[0].supply = "iovcc";
>> -       sii902x->supplies[1].supply = "cvcc12";
>> -       ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(sii902x->supplies),
>> -                                     sii902x->supplies);
>> -       if (ret < 0)
>> -               return ret;
>> -
>> -       ret = regulator_bulk_enable(ARRAY_SIZE(sii902x->supplies),
>> -                                   sii902x->supplies);
>> +       ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(supplies), supplies);
>>          if (ret < 0) {
>>                  dev_err_probe(dev, ret, "Failed to enable supplies");
>>                  return ret;
>>          }
>>
>> -       ret = sii902x_init(sii902x);
>> -       if (ret < 0) {
>> -               regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
>> -                                      sii902x->supplies);
>> -       }
>> -
>> -       return ret;
>> +       return sii902x_init(sii902x);
>>   }
>>
>>   static int sii902x_remove(struct i2c_client *client)
>> @@ -1152,8 +1138,6 @@ static int sii902x_remove(struct i2c_client *client)
>>
>>          i2c_mux_del_adapters(sii902x->i2cmux);
>>          drm_bridge_remove(&sii902x->bridge);
>> -       regulator_bulk_disable(ARRAY_SIZE(sii902x->supplies),
>> -                              sii902x->supplies);
>>
>>          return 0;
>>   }
> 
> Ideally this patch would be split into two parts here, due to
> maintainership boundaries.

Ok. I will in any case respin this series when the dependency patches 
from Mark's tree have been merged to the -rc1. I can split this to 
patch/driver if it is preferred. I just though I'll decrease amount of 
mails by squashing these almost trivial changes.

> 
> For the sii902x part, please add my r-b.
> 
> Reviewed-by: Robert Foss <robert.foss@linaro.org>
Thanks.

Best Regards
  -- Matti

-- 
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

~~ When things go utterly wrong vim users can always type :help! ~~

Discuss - Estimate - Plan - Report and finally accomplish this:
void do_work(int time) __attribute__ ((const));