2024-02-13 18:32:07

by Dan Carpenter

Subject: [PATCH] drm/imx/dcss: fix resource size calculation

The resource is inclusive of the ->start and ->end addresses so this
calculation is not correct. It should be "res->end - res->start + 1".
Use the resource_size() to do the calculation.

Fixes: 90393c9b5408 ("drm/imx/dcss: request memory region")
Signed-off-by: Dan Carpenter <[email protected]>
---
From static analysis. Not tested.

drivers/gpu/drm/imx/dcss/dcss-dev.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.c b/drivers/gpu/drm/imx/dcss/dcss-dev.c
index 597e9b7bd4bf..7fd0c4c14205 100644
--- a/drivers/gpu/drm/imx/dcss/dcss-dev.c
+++ b/drivers/gpu/drm/imx/dcss/dcss-dev.c
@@ -167,7 +167,6 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
struct resource *res;
struct dcss_dev *dcss;
const struct dcss_type_data *devtype;
- resource_size_t res_len;

devtype = of_device_get_match_data(dev);
if (!devtype) {
@@ -181,8 +180,7 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
return ERR_PTR(-EINVAL);
}

- res_len = res->end - res->start;
- if (!devm_request_mem_region(dev, res->start, res_len, "dcss")) {
+ if (!devm_request_mem_region(dev, res->start, resource_size(res), "dcss")) {
dev_err(dev, "cannot request memory region\n");
return ERR_PTR(-EBUSY);
}
--
2.43.0

2024-02-28 09:29:11

by Laurentiu Palcu

Subject: Re: [PATCH] drm/imx/dcss: fix resource size calculation

Hi Dan,

On Tue, Feb 13, 2024 at 09:05:01PM +0300, Dan Carpenter wrote:
> The resource is inclusive of the ->start and ->end addresses so this
> calculation is not correct. It should be "res->end - res->start + 1".
> Use the resource_size() to do the calculation.
>
> Fixes: 90393c9b5408 ("drm/imx/dcss: request memory region")
> Signed-off-by: Dan Carpenter <[email protected]>

Reviewed-by: Laurentiu Palcu <[email protected]>

And pushed to drm-misc-next-fixes.

Thanks,
Laurentiu

> ---
> From static analysis. Not tested.
>
> drivers/gpu/drm/imx/dcss/dcss-dev.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/imx/dcss/dcss-dev.c b/drivers/gpu/drm/imx/dcss/dcss-dev.c
> index 597e9b7bd4bf..7fd0c4c14205 100644
> --- a/drivers/gpu/drm/imx/dcss/dcss-dev.c
> +++ b/drivers/gpu/drm/imx/dcss/dcss-dev.c
> @@ -167,7 +167,6 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
> struct resource *res;
> struct dcss_dev *dcss;
> const struct dcss_type_data *devtype;
> - resource_size_t res_len;
>
> devtype = of_device_get_match_data(dev);
> if (!devtype) {
> @@ -181,8 +180,7 @@ struct dcss_dev *dcss_dev_create(struct device *dev, bool hdmi_output)
> return ERR_PTR(-EINVAL);
> }
>
> - res_len = res->end - res->start;
> - if (!devm_request_mem_region(dev, res->start, res_len, "dcss")) {
> + if (!devm_request_mem_region(dev, res->start, resource_size(res), "dcss")) {
> dev_err(dev, "cannot request memory region\n");
> return ERR_PTR(-EBUSY);
> }
> --
> 2.43.0
>