2023-07-22 11:57:52

by Krzysztof Kozlowski

Subject: [PATCH 3/3] media: exynos4-is: fimc-is: replace duplicate pmu node with phandle

Devicetree for the FIMC IS camera included duplicated PMU node as its
child like:

soc@0 {
system-controller@10020000 { ... }; // Real PMU

camera@11800000 {
fimc-is@12000000 {
// FIMC IS camera node
pmu@10020000 {
reg = <0x10020000 0x3000>; // Fake PMU node
};
};
};
};

This is not a correct representation of the hardware. Mapping the PMU
(Power Management Unit) IO memory should be via syscon-like phandle
(samsung,pmu-syscon, already used for other drivers), not by duplicating
"pmu" Devicetree node inside the FIMC IS. Backward compatibility is
preserved.

Signed-off-by: Krzysztof Kozlowski <[email protected]>
---
.../platform/samsung/exynos4-is/fimc-is.c | 33 ++++++++++++++-----
1 file changed, 24 insertions(+), 9 deletions(-)

diff --git a/drivers/media/platform/samsung/exynos4-is/fimc-is.c b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
index 530a148fe4d3..c4c191771093 100644
--- a/drivers/media/platform/samsung/exynos4-is/fimc-is.c
+++ b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
@@ -767,12 +767,32 @@ static void fimc_is_debugfs_create(struct fimc_is *is)
static int fimc_is_runtime_resume(struct device *dev);
static int fimc_is_runtime_suspend(struct device *dev);

+static void __iomem *fimc_is_get_pmu_regs(struct device *dev)
+{
+ struct device_node *node;
+ void __iomem *regs;
+
+ node = of_parse_phandle(dev->of_node, "samsung,pmu-syscon", 0);
+ if (!node) {
+ dev_warn(dev, "Finding PMU node via deprecated method, update your DTB\n");
+ node = of_get_child_by_name(dev->of_node, "pmu");
+ if (!node)
+ return ERR_PTR(-ENODEV);
+ }
+
+ regs = of_iomap(node, 0);
+ of_node_put(node);
+ if (!regs)
+ return ERR_PTR(-ENOMEM);
+
+ return regs;
+}
+
static int fimc_is_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fimc_is *is;
struct resource res;
- struct device_node *node;
int ret;

is = devm_kzalloc(&pdev->dev, sizeof(*is), GFP_KERNEL);
@@ -794,14 +814,9 @@ static int fimc_is_probe(struct platform_device *pdev)
if (IS_ERR(is->regs))
return PTR_ERR(is->regs);

- node = of_get_child_by_name(dev->of_node, "pmu");
- if (!node)
- return -ENODEV;
-
- is->pmu_regs = of_iomap(node, 0);
- of_node_put(node);
- if (!is->pmu_regs)
- return -ENOMEM;
+ is->pmu_regs = fimc_is_get_pmu_regs(dev);
+ if (IS_ERR(is->pmu_regs))
+ return PTR_ERR(is->pmu_regs);

is->irq = irq_of_parse_and_map(dev->of_node, 0);
if (!is->irq) {
--
2.34.1

2023-08-07 13:55:24

by Hans Verkuil

Subject: Re: [PATCH 3/3] media: exynos4-is: fimc-is: replace duplicate pmu node with phandle

Hi Krzysztof,

On 22/07/2023 13:54, Krzysztof Kozlowski wrote:
> Devicetree for the FIMC IS camera included duplicated PMU node as its
> child like:
>
> soc@0 {
> system-controller@10020000 { ... }; // Real PMU
>
> camera@11800000 {
> fimc-is@12000000 {
> // FIMC IS camera node
> pmu@10020000 {
> reg = <0x10020000 0x3000>; // Fake PMU node
> };
> };
> };
> };
>
> This is not a correct representation of the hardware. Mapping the PMU
> (Power Management Unit) IO memory should be via syscon-like phandle
> (samsung,pmu-syscon, already used for other drivers), not by duplicating
> "pmu" Devicetree node inside the FIMC IS. Backward compatibility is
> preserved.
>
> Signed-off-by: Krzysztof Kozlowski <[email protected]>
> ---
> .../platform/samsung/exynos4-is/fimc-is.c | 33 ++++++++++++++-----
> 1 file changed, 24 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/media/platform/samsung/exynos4-is/fimc-is.c b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
> index 530a148fe4d3..c4c191771093 100644
> --- a/drivers/media/platform/samsung/exynos4-is/fimc-is.c
> +++ b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
> @@ -767,12 +767,32 @@ static void fimc_is_debugfs_create(struct fimc_is *is)
> static int fimc_is_runtime_resume(struct device *dev);
> static int fimc_is_runtime_suspend(struct device *dev);
>
> +static void __iomem *fimc_is_get_pmu_regs(struct device *dev)
> +{
> + struct device_node *node;
> + void __iomem *regs;
> +
> + node = of_parse_phandle(dev->of_node, "samsung,pmu-syscon", 0);
> + if (!node) {
> + dev_warn(dev, "Finding PMU node via deprecated method, update your DTB\n");
> + node = of_get_child_by_name(dev->of_node, "pmu");
> + if (!node)
> + return ERR_PTR(-ENODEV);
> + }
> +
> + regs = of_iomap(node, 0);
> + of_node_put(node);
> + if (!regs)
> + return ERR_PTR(-ENOMEM);

sparse gives me these warnings for these ERR_PTR returns:

drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: warning: incorrect type in return expression (different address spaces)
drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: expected void [noderef] __iomem *
drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: got void *
drivers/media/platform/samsung/exynos4-is/fimc-is.c:786:31: warning: incorrect type in return expression (different address spaces)
drivers/media/platform/samsung/exynos4-is/fimc-is.c:786:31: expected void [noderef] __iomem *
drivers/media/platform/samsung/exynos4-is/fimc-is.c:786:31: got void *

Regards,

Hans

> +
> + return regs;
> +}
> +
> static int fimc_is_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> struct fimc_is *is;
> struct resource res;
> - struct device_node *node;
> int ret;
>
> is = devm_kzalloc(&pdev->dev, sizeof(*is), GFP_KERNEL);
> @@ -794,14 +814,9 @@ static int fimc_is_probe(struct platform_device *pdev)
> if (IS_ERR(is->regs))
> return PTR_ERR(is->regs);
>
> - node = of_get_child_by_name(dev->of_node, "pmu");
> - if (!node)
> - return -ENODEV;
> -
> - is->pmu_regs = of_iomap(node, 0);
> - of_node_put(node);
> - if (!is->pmu_regs)
> - return -ENOMEM;
> + is->pmu_regs = fimc_is_get_pmu_regs(dev);
> + if (IS_ERR(is->pmu_regs))
> + return PTR_ERR(is->pmu_regs);
>
> is->irq = irq_of_parse_and_map(dev->of_node, 0);
> if (!is->irq) {

2023-08-07 15:10:24

by Krzysztof Kozlowski

Subject: Re: [PATCH 3/3] media: exynos4-is: fimc-is: replace duplicate pmu node with phandle

On 07/08/2023 15:06, Hans Verkuil wrote:
> Hi Krzysztof,
>
> On 22/07/2023 13:54, Krzysztof Kozlowski wrote:
>> Devicetree for the FIMC IS camera included duplicated PMU node as its
>> child like:
>>
>> soc@0 {
>> system-controller@10020000 { ... }; // Real PMU
>>
>> camera@11800000 {
>> fimc-is@12000000 {
>> // FIMC IS camera node
>> pmu@10020000 {
>> reg = <0x10020000 0x3000>; // Fake PMU node
>> };
>> };
>> };
>> };
>>
>> This is not a correct representation of the hardware. Mapping the PMU
>> (Power Management Unit) IO memory should be via syscon-like phandle
>> (samsung,pmu-syscon, already used for other drivers), not by duplicating
>> "pmu" Devicetree node inside the FIMC IS. Backward compatibility is
>> preserved.
>>
>> Signed-off-by: Krzysztof Kozlowski <[email protected]>
>> ---
>> .../platform/samsung/exynos4-is/fimc-is.c | 33 ++++++++++++++-----
>> 1 file changed, 24 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/media/platform/samsung/exynos4-is/fimc-is.c b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
>> index 530a148fe4d3..c4c191771093 100644
>> --- a/drivers/media/platform/samsung/exynos4-is/fimc-is.c
>> +++ b/drivers/media/platform/samsung/exynos4-is/fimc-is.c
>> @@ -767,12 +767,32 @@ static void fimc_is_debugfs_create(struct fimc_is *is)
>> static int fimc_is_runtime_resume(struct device *dev);
>> static int fimc_is_runtime_suspend(struct device *dev);
>>
>> +static void __iomem *fimc_is_get_pmu_regs(struct device *dev)
>> +{
>> + struct device_node *node;
>> + void __iomem *regs;
>> +
>> + node = of_parse_phandle(dev->of_node, "samsung,pmu-syscon", 0);
>> + if (!node) {
>> + dev_warn(dev, "Finding PMU node via deprecated method, update your DTB\n");
>> + node = of_get_child_by_name(dev->of_node, "pmu");
>> + if (!node)
>> + return ERR_PTR(-ENODEV);
>> + }
>> +
>> + regs = of_iomap(node, 0);
>> + of_node_put(node);
>> + if (!regs)
>> + return ERR_PTR(-ENOMEM);
>
> sparse gives me these warnings for these ERR_PTR returns:
>
> drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: warning: incorrect type in return expression (different address spaces)
> drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: expected void [noderef] __iomem *
> drivers/media/platform/samsung/exynos4-is/fimc-is.c:780:39: got void *

Thanks, indeed. I will use IOMEM_ERR_PTR()

Best regards,
Krzysztof