[PATCH 0/2] drivers: media: struct bus_type cleanup

[PATCH 0/2] drivers: media: struct bus_type cleanup

[Ricardo B. Marliere]

This series is part of an effort to cleanup the users of the driver
core, as can be seen in many recent patches authored by Greg across the
tree (e.g. [1]). Specifically, this series is part of the task of
splitting one of his TODOs [2].

---
[1]: https://lore.kernel.org/lkml/?q=f%3Agregkh%40linuxfoundation.org+s%3A%22make%22+and+s%3A%22const%22
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git/commit/?h=bus_cleanup&id=26105f537f0c60eacfeb430abd2e05d7ddcdd8aa

Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>

---
Ricardo B. Marliere (2):
      media: cec: make cec_bus_type const
      media: media-devnode: make media_bus_type const

 drivers/media/cec/core/cec-core.c | 2 +-
 drivers/media/mc/mc-devnode.c     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
base-commit: 41bccc98fb7931d63d03f326a746ac4d429c1dd3
change-id: 20240203-bus_cleanup-media-0ee6e332fef5

Best regards,
-- 
Ricardo B. Marliere <ricardo@marliere.net>

[PATCH 1/2] media: cec: make cec_bus_type const

[Ricardo B. Marliere]

Now that the driver core can properly handle constant struct bus_type,
move the cec_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
---
 drivers/media/cec/core/cec-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
index 7e153c5cad04..5a54db839e5d 100644
--- a/drivers/media/cec/core/cec-core.c
+++ b/drivers/media/cec/core/cec-core.c
@@ -93,7 +93,7 @@ static void cec_devnode_release(struct device *cd)
 	cec_delete_adapter(to_cec_adapter(devnode));
 }
 
-static struct bus_type cec_bus_type = {
+static const struct bus_type cec_bus_type = {
 	.name = CEC_NAME,
 };
 

-- 
2.43.0

Re: [PATCH 1/2] media: cec: make cec_bus_type const

[Greg Kroah-Hartman]

On Sat, Feb 03, 2024 at 12:31:26PM -0300, Ricardo B. Marliere wrote:
> Now that the driver core can properly handle constant struct bus_type,
> move the cec_bus_type variable to be a constant structure as well,
> placing it into read-only memory which can not be modified at runtime.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
> ---
>  drivers/media/cec/core/cec-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH 1/2] media: cec: make cec_bus_type const

[Laurent Pinchart]

Hi Ricardo,

Thank you for the patch.

On Sat, Feb 03, 2024 at 12:31:26PM -0300, Ricardo B. Marliere wrote:
> Now that the driver core can properly handle constant struct bus_type,
> move the cec_bus_type variable to be a constant structure as well,
> placing it into read-only memory which can not be modified at runtime.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Hans, I assume you'll pick this patch. Could you also pick 2/2 from the
series ?

> ---
>  drivers/media/cec/core/cec-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
> index 7e153c5cad04..5a54db839e5d 100644
> --- a/drivers/media/cec/core/cec-core.c
> +++ b/drivers/media/cec/core/cec-core.c
> @@ -93,7 +93,7 @@ static void cec_devnode_release(struct device *cd)
>  	cec_delete_adapter(to_cec_adapter(devnode));
>  }
>  
> -static struct bus_type cec_bus_type = {
> +static const struct bus_type cec_bus_type = {
>  	.name = CEC_NAME,
>  };
>  

-- 
Regards,

Laurent Pinchart

Re: [PATCH 1/2] media: cec: make cec_bus_type const

[Hans Verkuil]

On 04/02/2024 09:47, Laurent Pinchart wrote:
> Hi Ricardo,
> 
> Thank you for the patch.
> 
> On Sat, Feb 03, 2024 at 12:31:26PM -0300, Ricardo B. Marliere wrote:
>> Now that the driver core can properly handle constant struct bus_type,
>> move the cec_bus_type variable to be a constant structure as well,
>> placing it into read-only memory which can not be modified at runtime.
>>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> 
> Hans, I assume you'll pick this patch. Could you also pick 2/2 from the
> series ?

Of course!

	Hans

> 
>> ---
>>  drivers/media/cec/core/cec-core.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/media/cec/core/cec-core.c b/drivers/media/cec/core/cec-core.c
>> index 7e153c5cad04..5a54db839e5d 100644
>> --- a/drivers/media/cec/core/cec-core.c
>> +++ b/drivers/media/cec/core/cec-core.c
>> @@ -93,7 +93,7 @@ static void cec_devnode_release(struct device *cd)
>>  	cec_delete_adapter(to_cec_adapter(devnode));
>>  }
>>  
>> -static struct bus_type cec_bus_type = {
>> +static const struct bus_type cec_bus_type = {
>>  	.name = CEC_NAME,
>>  };
>>  
> 

[PATCH 2/2] media: media-devnode: make media_bus_type const

[Ricardo B. Marliere]

Now that the driver core can properly handle constant struct bus_type,
move the media_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
---
 drivers/media/mc/mc-devnode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c
index 680fbb3a9340..90646805bd81 100644
--- a/drivers/media/mc/mc-devnode.c
+++ b/drivers/media/mc/mc-devnode.c
@@ -63,7 +63,7 @@ static void media_devnode_release(struct device *cd)
 	pr_debug("%s: Media Devnode Deallocated\n", __func__);
 }
 
-static struct bus_type media_bus_type = {
+static const struct bus_type media_bus_type = {
 	.name = MEDIA_NAME,
 };
 

-- 
2.43.0

Re: [PATCH 2/2] media: media-devnode: make media_bus_type const

[Greg Kroah-Hartman]

On Sat, Feb 03, 2024 at 12:31:27PM -0300, Ricardo B. Marliere wrote:
> Now that the driver core can properly handle constant struct bus_type,
> move the media_bus_type variable to be a constant structure as well,
> placing it into read-only memory which can not be modified at runtime.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
> ---
>  drivers/media/mc/mc-devnode.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Re: [PATCH 2/2] media: media-devnode: make media_bus_type const

[Laurent Pinchart]

Hi Ricardo,

Thank you for the patch.

On Sat, Feb 03, 2024 at 12:31:27PM -0300, Ricardo B. Marliere wrote:
> Now that the driver core can properly handle constant struct bus_type,
> move the media_bus_type variable to be a constant structure as well,
> placing it into read-only memory which can not be modified at runtime.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>

Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

> ---
>  drivers/media/mc/mc-devnode.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c
> index 680fbb3a9340..90646805bd81 100644
> --- a/drivers/media/mc/mc-devnode.c
> +++ b/drivers/media/mc/mc-devnode.c
> @@ -63,7 +63,7 @@ static void media_devnode_release(struct device *cd)
>  	pr_debug("%s: Media Devnode Deallocated\n", __func__);
>  }
>  
> -static struct bus_type media_bus_type = {
> +static const struct bus_type media_bus_type = {
>  	.name = MEDIA_NAME,
>  };
>  
> 

-- 
Regards,

Laurent Pinchart