[PATCH v2 0/3] Return immediately if sprd_clk_regmap_init() fails

[PATCH v2 0/3] Return immediately if sprd_clk_regmap_init() fails

[Chunyan Zhang]

The function sprd_clk_regmap_init() doesn't always return success,
drivers should return immediately when it fails ranther than
continue the clock initialization.

The patch 1/3 in this set switchs to use devm_ioremap_resources()
instead of of_iomap(), that will make caller programs more simple.

Chunyan Zhang (3):
  clk: sprd: Switch from of_iomap() to devm_ioremap_resource()
  clk: sprd: Check error only for devm_regmap_init_mmio()
  clk: sprd: Add check the return value of sprd_clk_regmap_init()

 drivers/clk/sprd/common.c     | 9 +++++++--
 drivers/clk/sprd/sc9860-clk.c | 4 +++-
 2 files changed, 10 insertions(+), 3 deletions(-)

-- 
2.17.1

[PATCH v2 1/3] clk: sprd: Switch from of_iomap() to devm_ioremap_resource()

[Chunyan Zhang]

devm_ioremap_resources() automatically requests resources and devm_ wrappers
do better error handling and unmapping of the I/O region when needed,
that would make drivers more clean and simple.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
---
 drivers/clk/sprd/common.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
index e038b0447206..9ce690999eaa 100644
--- a/drivers/clk/sprd/common.c
+++ b/drivers/clk/sprd/common.c
@@ -42,6 +42,7 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
 	void __iomem *base;
 	struct device_node *node = pdev->dev.of_node;
 	struct regmap *regmap;
+	struct resource *res;
 
 	if (of_find_property(node, "sprd,syscon", NULL)) {
 		regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
@@ -50,7 +51,11 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
 			return PTR_ERR(regmap);
 		}
 	} else {
-		base = of_iomap(node, 0);
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+		base = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(base))
+			return PTR_ERR(base);
+
 		regmap = devm_regmap_init_mmio(&pdev->dev, base,
 					       &sprdclk_regmap_config);
 		if (IS_ERR_OR_NULL(regmap)) {
-- 
2.17.1

[PATCH v2 2/3] clk: sprd: Check error only for devm_regmap_init_mmio()

[Chunyan Zhang]

The function devm_regmap_init_mmio() wouldn't return NULL pointer for
now, so only need to ensure the return value is not an error code.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
---
 drivers/clk/sprd/common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
index 9ce690999eaa..a5bdca1de5d0 100644
--- a/drivers/clk/sprd/common.c
+++ b/drivers/clk/sprd/common.c
@@ -58,7 +58,7 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
 
 		regmap = devm_regmap_init_mmio(&pdev->dev, base,
 					       &sprdclk_regmap_config);
-		if (IS_ERR_OR_NULL(regmap)) {
+		if (IS_ERR(regmap)) {
 			pr_err("failed to init regmap\n");
 			return PTR_ERR(regmap);
 		}
-- 
2.17.1

[PATCH v2 3/3] clk: sprd: Add check for return value of sprd_clk_regmap_init()

[Chunyan Zhang]

sprd_clk_regmap_init() doesn't always return success, adding check
for its return value should make the code more strong.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/clk/sprd/sc9860-clk.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sprd/sc9860-clk.c b/drivers/clk/sprd/sc9860-clk.c
index 9980ab55271b..1ed45b4f2fe8 100644
--- a/drivers/clk/sprd/sc9860-clk.c
+++ b/drivers/clk/sprd/sc9860-clk.c
@@ -2031,7 +2031,9 @@ static int sc9860_clk_probe(struct platform_device *pdev)
 	}
 
 	desc = match->data;
-	sprd_clk_regmap_init(pdev, desc);
+	ret = sprd_clk_regmap_init(pdev, desc);
+	if (ret)
+		return ret;
 
 	return sprd_clk_probe(&pdev->dev, desc->hw_clks);
 }
-- 
2.17.1

[PATCH v2 3/3] clk: sprd: Add check the return value of sprd_clk_regmap_init()

[Chunyan Zhang]

sprd_clk_regmap_init() doesn't always return success, adding check
for its return value should make the code more strong.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
---
 drivers/clk/sprd/sc9860-clk.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sprd/sc9860-clk.c b/drivers/clk/sprd/sc9860-clk.c
index 9980ab55271b..1ed45b4f2fe8 100644
--- a/drivers/clk/sprd/sc9860-clk.c
+++ b/drivers/clk/sprd/sc9860-clk.c
@@ -2031,7 +2031,9 @@ static int sc9860_clk_probe(struct platform_device *pdev)
 	}
 
 	desc = match->data;
-	sprd_clk_regmap_init(pdev, desc);
+	ret = sprd_clk_regmap_init(pdev, desc);
+	if (ret)
+		return ret;
 
 	return sprd_clk_probe(&pdev->dev, desc->hw_clks);
 }
-- 
2.17.1

[PATCH v2 0/3] Return immediately if sprd_clk_regmap_init() fails

[Chunyan Zhang]

The function sprd_clk_regmap_init() doesn't always return success,
drivers should return immediately when it fails rather than
continue the clock initialization.

The patch 1/3 in this set switchs to use devm_ioremap_resources()
instead of of_iomap(), that will make caller programs more simple.

Changes from V1:
- Split out the patch 2/3 from 1/2 of the first version;
- Added reviewed-by from Baolin.

Chunyan Zhang (3):
  clk: sprd: Switch from of_iomap() to devm_ioremap_resource()
  clk: sprd: Check error only for devm_regmap_init_mmio()
  clk: sprd: Add check the return value of sprd_clk_regmap_init()

 drivers/clk/sprd/common.c     | 9 +++++++--
 drivers/clk/sprd/sc9860-clk.c | 4 +++-
 2 files changed, 10 insertions(+), 3 deletions(-)

-- 
2.17.1

Re: [PATCH v2 1/3] clk: sprd: Switch from of_iomap() to devm_ioremap_resource()

[Baolin Wang]

On Wed, 22 May 2019 at 09:15, Chunyan Zhang <zhang.chunyan@linaro.org> wrote:
>
> devm_ioremap_resources() automatically requests resources and devm_ wrappers
> do better error handling and unmapping of the I/O region when needed,
> that would make drivers more clean and simple.
>
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>

Reviewed-by: Baolin Wang <baolin.wang@linaro.org>

> ---
>  drivers/clk/sprd/common.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
> index e038b0447206..9ce690999eaa 100644
> --- a/drivers/clk/sprd/common.c
> +++ b/drivers/clk/sprd/common.c
> @@ -42,6 +42,7 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
>         void __iomem *base;
>         struct device_node *node = pdev->dev.of_node;
>         struct regmap *regmap;
> +       struct resource *res;
>
>         if (of_find_property(node, "sprd,syscon", NULL)) {
>                 regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
> @@ -50,7 +51,11 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
>                         return PTR_ERR(regmap);
>                 }
>         } else {
> -               base = of_iomap(node, 0);
> +               res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +               base = devm_ioremap_resource(&pdev->dev, res);
> +               if (IS_ERR(base))
> +                       return PTR_ERR(base);
> +
>                 regmap = devm_regmap_init_mmio(&pdev->dev, base,
>                                                &sprdclk_regmap_config);
>                 if (IS_ERR_OR_NULL(regmap)) {
> --
> 2.17.1
>


-- 
Baolin Wang
Best Regards

Re: [PATCH v2 2/3] clk: sprd: Check error only for devm_regmap_init_mmio()

[Baolin Wang]

On Wed, 22 May 2019 at 09:15, Chunyan Zhang <zhang.chunyan@linaro.org> wrote:
>
> The function devm_regmap_init_mmio() wouldn't return NULL pointer for
> now, so only need to ensure the return value is not an error code.
>
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>

Reviewed-by: Baolin Wang <baolin.wang@linaro.org>

> ---
>  drivers/clk/sprd/common.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
> index 9ce690999eaa..a5bdca1de5d0 100644
> --- a/drivers/clk/sprd/common.c
> +++ b/drivers/clk/sprd/common.c
> @@ -58,7 +58,7 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
>
>                 regmap = devm_regmap_init_mmio(&pdev->dev, base,
>                                                &sprdclk_regmap_config);
> -               if (IS_ERR_OR_NULL(regmap)) {
> +               if (IS_ERR(regmap)) {
>                         pr_err("failed to init regmap\n");
>                         return PTR_ERR(regmap);
>                 }
> --
> 2.17.1
>


-- 
Baolin Wang
Best Regards

Re: [PATCH v2 1/3] clk: sprd: Switch from of_iomap() to devm_ioremap_resource()

[Stephen Boyd]

Quoting Chunyan Zhang (2019-05-21 18:15:01)
> devm_ioremap_resources() automatically requests resources and devm_ wrappers
> do better error handling and unmapping of the I/O region when needed,
> that would make drivers more clean and simple.
> 
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>

Applied to clk-next

> diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
> index e038b0447206..9ce690999eaa 100644
> --- a/drivers/clk/sprd/common.c
> +++ b/drivers/clk/sprd/common.c
> @@ -50,7 +51,11 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
>                         return PTR_ERR(regmap);
>                 }
>         } else {
> -               base = of_iomap(node, 0);
> +               res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +               base = devm_ioremap_resource(&pdev->dev, res);
> +               if (IS_ERR(base))

There's also devm_platform_ioremap_resource() if you want to save even
more lines!

> +                       return PTR_ERR(base);
> +

Re: [PATCH v2 2/3] clk: sprd: Check error only for devm_regmap_init_mmio()

[Stephen Boyd]

Quoting Chunyan Zhang (2019-05-21 18:15:02)
> The function devm_regmap_init_mmio() wouldn't return NULL pointer for
> now, so only need to ensure the return value is not an error code.
> 
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
> ---

Applied to clk-next

Re: [PATCH v2 3/3] clk: sprd: Add check for return value of sprd_clk_regmap_init()

[Stephen Boyd]

Quoting Chunyan Zhang (2019-05-21 18:15:03)
> sprd_clk_regmap_init() doesn't always return success, adding check
> for its return value should make the code more strong.
> 
> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
> Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
> ---

Applied to clk-next

Re: [PATCH v2 1/3] clk: sprd: Switch from of_iomap() to devm_ioremap_resource()

[Chunyan Zhang]

On Thu, 27 Jun 2019 at 02:16, Stephen Boyd <sboyd@kernel.org> wrote:
>
> Quoting Chunyan Zhang (2019-05-21 18:15:01)
> > devm_ioremap_resources() automatically requests resources and devm_ wrappers
> > do better error handling and unmapping of the I/O region when needed,
> > that would make drivers more clean and simple.
> >
> > Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
>
> Applied to clk-next
>
> > diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
> > index e038b0447206..9ce690999eaa 100644
> > --- a/drivers/clk/sprd/common.c
> > +++ b/drivers/clk/sprd/common.c
> > @@ -50,7 +51,11 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
> >                         return PTR_ERR(regmap);
> >                 }
> >         } else {
> > -               base = of_iomap(node, 0);
> > +               res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +               base = devm_ioremap_resource(&pdev->dev, res);
> > +               if (IS_ERR(base))
>
> There's also devm_platform_ioremap_resource() if you want to save even
> more lines!

Yes indeed, thanks for the information.
Considering this patch was queued to your tree, I decide to use this
more integrated function later :)

Cheers,
Chunyan

>
> > +                       return PTR_ERR(base);
> > +