[PATCH 0/3] reset: Miscellaneous improvements

[PATCH 0/3] reset: Miscellaneous improvements

[Geert Uytterhoeven]

	Hi Philipp,

This patch series contains a resource optimization for the managed
helpers, a kerneldoc fix, and an enhancement to make the reset
controller code more uniform.

Thanks!

Geert Uytterhoeven (3):
  reset: Do not register resource data for missing resets
  reset: Fix {of,devm}_reset_control_array_get kerneldoc return types
  reset: Align logic and flow in managed helpers

 drivers/reset/core.c | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)

-- 
2.17.1

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

[PATCH 1/3] reset: Do not register resource data for missing resets

[Geert Uytterhoeven]

When an optional reset is not present, __devm_reset_control_get() and
devm_reset_control_array_get() still register resource data to release
the non-existing reset on cleanup, which is futile.

Fix this by skipping NULL reset control pointers.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/reset/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index ca1d49146f611435..55245f485b3819da 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -787,7 +787,7 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
 		return ERR_PTR(-ENOMEM);
 
 	rstc = __reset_control_get(dev, id, index, shared, optional, acquired);
-	if (!IS_ERR(rstc)) {
+	if (rstc && !IS_ERR(rstc)) {
 		*ptr = rstc;
 		devres_add(dev, ptr);
 	} else {
@@ -930,7 +930,7 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
 		return ERR_PTR(-ENOMEM);
 
 	rstc = of_reset_control_array_get(dev->of_node, shared, optional, true);
-	if (IS_ERR(rstc)) {
+	if (!rstc || IS_ERR(rstc)) {
 		devres_free(devres);
 		return rstc;
 	}
-- 
2.17.1

[PATCH 2/3] reset: Fix {of,devm}_reset_control_array_get kerneldoc return types

[Geert Uytterhoeven]

of_reset_control_array_get() and devm_reset_control_array_get() return
struct reset_control pointers, not internal struct reset_control_array
pointers, just like all other reset control API calls.

Correct the kerneldoc to match the code.

Fixes: 17c82e206d2a3cd8 ("reset: Add APIs to manage array of resets")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/reset/core.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index 55245f485b3819da..4ea62aa00260f82c 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -861,8 +861,7 @@ static int of_reset_control_get_count(struct device_node *node)
  * @acquired: only one reset control may be acquired for a given controller
  *            and ID
  *
- * Returns pointer to allocated reset_control_array on success or
- * error on failure
+ * Returns pointer to allocated reset_control on success or error on failure
  */
 struct reset_control *
 of_reset_control_array_get(struct device_node *np, bool shared, bool optional,
@@ -915,8 +914,7 @@ EXPORT_SYMBOL_GPL(of_reset_control_array_get);
  * that just have to be asserted or deasserted, without any
  * requirements on the order.
  *
- * Returns pointer to allocated reset_control_array on success or
- * error on failure
+ * Returns pointer to allocated reset_control on success or error on failure
  */
 struct reset_control *
 devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
-- 
2.17.1

[PATCH 3/3] reset: Align logic and flow in managed helpers

[Geert Uytterhoeven]

__devm_reset_control_get() and devm_reset_control_array_get() are very
similar, but they do not look similar, due to inverted logic.
Make them more similar, following the "bail out early" paradigm.

Adjust the logic and flow in devm_reset_controller_register() to match
the two other functions.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/reset/core.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index 4ea62aa00260f82c..763f1353d386519b 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -150,13 +150,14 @@ int devm_reset_controller_register(struct device *dev,
 		return -ENOMEM;
 
 	ret = reset_controller_register(rcdev);
-	if (!ret) {
-		*rcdevp = rcdev;
-		devres_add(dev, rcdevp);
-	} else {
+	if (ret) {
 		devres_free(rcdevp);
+		return ret;
 	}
 
+	*rcdevp = rcdev;
+	devres_add(dev, rcdevp);
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(devm_reset_controller_register);
@@ -787,13 +788,14 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
 		return ERR_PTR(-ENOMEM);
 
 	rstc = __reset_control_get(dev, id, index, shared, optional, acquired);
-	if (rstc && !IS_ERR(rstc)) {
-		*ptr = rstc;
-		devres_add(dev, ptr);
-	} else {
+	if (!rstc || IS_ERR(rstc)) {
 		devres_free(ptr);
+		return rstc;
 	}
 
+	*ptr = rstc;
+	devres_add(dev, ptr);
+
 	return rstc;
 }
 EXPORT_SYMBOL_GPL(__devm_reset_control_get);
@@ -919,22 +921,21 @@ EXPORT_SYMBOL_GPL(of_reset_control_array_get);
 struct reset_control *
 devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
 {
-	struct reset_control **devres;
-	struct reset_control *rstc;
+	struct reset_control **ptr, *rstc;
 
-	devres = devres_alloc(devm_reset_control_release, sizeof(*devres),
-			      GFP_KERNEL);
-	if (!devres)
+	ptr = devres_alloc(devm_reset_control_release, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
 		return ERR_PTR(-ENOMEM);
 
 	rstc = of_reset_control_array_get(dev->of_node, shared, optional, true);
 	if (!rstc || IS_ERR(rstc)) {
-		devres_free(devres);
+		devres_free(ptr);
 		return rstc;
 	}
 
-	*devres = rstc;
-	devres_add(dev, devres);
+	*ptr = rstc;
+	devres_add(dev, ptr);
 
 	return rstc;
 }
-- 
2.17.1

Re: [PATCH 1/3] reset: Do not register resource data for missing resets

[Philipp Zabel]

Hi Geert,

thank you for the patches!

On Wed, 2019-11-20 at 15:26 +0100, Geert Uytterhoeven wrote:
> When an optional reset is not present, __devm_reset_control_get() and
> devm_reset_control_array_get() still register resource data to release
> the non-existing reset on cleanup, which is futile.
> 
> Fix this by skipping NULL reset control pointers.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/reset/core.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/reset/core.c b/drivers/reset/core.c
> index ca1d49146f611435..55245f485b3819da 100644
> --- a/drivers/reset/core.c
> +++ b/drivers/reset/core.c
> @@ -787,7 +787,7 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
>  		return ERR_PTR(-ENOMEM);
>  
>  	rstc = __reset_control_get(dev, id, index, shared, optional, acquired);
> -	if (!IS_ERR(rstc)) {
> +	if (rstc && !IS_ERR(rstc)) {

Could you change this to use IS_ERR_OR_NULL, both here and below?

>  		*ptr = rstc;
>  		devres_add(dev, ptr);
>  	} else {
> @@ -930,7 +930,7 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
>  		return ERR_PTR(-ENOMEM);
>  
>  	rstc = of_reset_control_array_get(dev->of_node, shared, optional, true);
> -	if (IS_ERR(rstc)) {
> +	if (!rstc || IS_ERR(rstc)) {
>  		devres_free(devres);
>  		return rstc;
>  	}

Same for patch 3, which otherwise looks fine.

regards
Philipp

Re: [PATCH 2/3] reset: Fix {of,devm}_reset_control_array_get kerneldoc return types

[Philipp Zabel]

On Wed, 2019-11-20 at 15:26 +0100, Geert Uytterhoeven wrote:
> of_reset_control_array_get() and devm_reset_control_array_get() return
> struct reset_control pointers, not internal struct reset_control_array
> pointers, just like all other reset control API calls.
> 
> Correct the kerneldoc to match the code.
> 
> Fixes: 17c82e206d2a3cd8 ("reset: Add APIs to manage array of resets")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
>  drivers/reset/core.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/reset/core.c b/drivers/reset/core.c
> index 55245f485b3819da..4ea62aa00260f82c 100644
> --- a/drivers/reset/core.c
> +++ b/drivers/reset/core.c
> @@ -861,8 +861,7 @@ static int of_reset_control_get_count(struct device_node *node)
>   * @acquired: only one reset control may be acquired for a given controller
>   *            and ID
>   *
> - * Returns pointer to allocated reset_control_array on success or
> - * error on failure
> + * Returns pointer to allocated reset_control on success or error on failure
>   */
>  struct reset_control *
>  of_reset_control_array_get(struct device_node *np, bool shared, bool optional,
> @@ -915,8 +914,7 @@ EXPORT_SYMBOL_GPL(of_reset_control_array_get);
>   * that just have to be asserted or deasserted, without any
>   * requirements on the order.
>   *
> - * Returns pointer to allocated reset_control_array on success or
> - * error on failure
> + * Returns pointer to allocated reset_control on success or error on failure
>   */
>  struct reset_control *
>  devm_reset_control_array_get(struct device *dev, bool shared, bool optional)

Thank you, applied to reset/fixes.

regards
Philipp

Re: [PATCH 1/3] reset: Do not register resource data for missing resets

[Geert Uytterhoeven]

Hi Philipp,

On Wed, Nov 20, 2019 at 3:43 PM Philipp Zabel <p.zabel@pengutronix.de> wrote:
> On Wed, 2019-11-20 at 15:26 +0100, Geert Uytterhoeven wrote:
> > When an optional reset is not present, __devm_reset_control_get() and
> > devm_reset_control_array_get() still register resource data to release
> > the non-existing reset on cleanup, which is futile.
> >
> > Fix this by skipping NULL reset control pointers.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > ---
> >  drivers/reset/core.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/reset/core.c b/drivers/reset/core.c
> > index ca1d49146f611435..55245f485b3819da 100644
> > --- a/drivers/reset/core.c
> > +++ b/drivers/reset/core.c
> > @@ -787,7 +787,7 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
> >               return ERR_PTR(-ENOMEM);
> >
> >       rstc = __reset_control_get(dev, id, index, shared, optional, acquired);
> > -     if (!IS_ERR(rstc)) {
> > +     if (rstc && !IS_ERR(rstc)) {
>
> Could you change this to use IS_ERR_OR_NULL, both here and below?

Sure. Silly me...
Thanks!

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds