[v12,5/6] staging: bcm2835-camera: Register bcm2835-camera with vchiq_bus_type

Message ID 20230923143200.268063-6-umang.jain@ideasonboard.com (mailing list archive)
State New
Headers
Series staging: vc04_services: vchiq: Register devices with a custom bus_type |

Commit Message

Umang Jain Sept. 23, 2023, 2:31 p.m. UTC
  Register the bcm2835-camera with the vchiq_bus_type instead of using
platform driver/device.

Since we moved away bcm2835-camera from platform driver/device,
we have to set the DMA mask explicitly. Set the DMA mask at probe
time.

Also the VCHIQ firmware doesn't support device enumeration, hence
one has to maintain a list of devices to be registered in the interface.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
---
 .../bcm2835-camera/bcm2835-camera.c           | 21 ++++++++++---------
 .../interface/vchiq_arm/vchiq_arm.c           | 11 +++++++---
 2 files changed, 19 insertions(+), 13 deletions(-)
  

Comments

Greg Kroah-Hartman Oct. 5, 2023, 8:04 a.m. UTC | #1
On Sat, Sep 23, 2023 at 08:01:59PM +0530, Umang Jain wrote:
> Register the bcm2835-camera with the vchiq_bus_type instead of using
> platform driver/device.
> 
> Since we moved away bcm2835-camera from platform driver/device,
> we have to set the DMA mask explicitly. Set the DMA mask at probe
> time.
> 
> Also the VCHIQ firmware doesn't support device enumeration, hence
> one has to maintain a list of devices to be registered in the interface.
> 
> Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
> ---
>  .../bcm2835-camera/bcm2835-camera.c           | 21 ++++++++++---------
>  .../interface/vchiq_arm/vchiq_arm.c           | 11 +++++++---
>  2 files changed, 19 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> index fcad5118f3e8..c873eace1437 100644
> --- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> +++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> @@ -11,6 +11,7 @@
>   *          Luke Diamand @ Broadcom
>   */
>  
> +#include <linux/dma-mapping.h>
>  #include <linux/errno.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> @@ -24,8 +25,8 @@
>  #include <media/v4l2-event.h>
>  #include <media/v4l2-common.h>
>  #include <linux/delay.h>
> -#include <linux/platform_device.h>
>  
> +#include "../interface/vchiq_arm/vchiq_bus.h"
>  #include "../vchiq-mmal/mmal-common.h"
>  #include "../vchiq-mmal/mmal-encodings.h"
>  #include "../vchiq-mmal/mmal-vchiq.h"
> @@ -1841,7 +1842,7 @@ static struct v4l2_format default_v4l2_format = {
>  	.fmt.pix.sizeimage = 1024 * 768,
>  };
>  
> -static int bcm2835_mmal_probe(struct platform_device *pdev)
> +static int bcm2835_mmal_probe(struct vchiq_device *device)
>  {
>  	int ret;
>  	struct bcm2835_mmal_dev *dev;
> @@ -1852,9 +1853,9 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>  	unsigned int resolutions[MAX_BCM2835_CAMERAS][2];
>  	int i;
>  
> -	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> +	ret = dma_set_mask_and_coherent(&device->dev, DMA_BIT_MASK(32));
>  	if (ret) {
> -		dev_err(&pdev->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
> +		dev_err(&device->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
>  		return ret;
>  	}
>  
> @@ -1902,7 +1903,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>  						       &camera_instance);
>  		ret = v4l2_device_register(NULL, &dev->v4l2_dev);
>  		if (ret) {
> -			dev_err(&pdev->dev, "%s: could not register V4L2 device: %d\n",
> +			dev_err(&device->dev, "%s: could not register V4L2 device: %d\n",
>  				__func__, ret);
>  			goto free_dev;
>  		}
> @@ -1982,7 +1983,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>  	return ret;
>  }
>  
> -static void bcm2835_mmal_remove(struct platform_device *pdev)
> +static void bcm2835_mmal_remove(struct vchiq_device *device)
>  {
>  	int camera;
>  	struct vchiq_mmal_instance *instance = gdev[0]->instance;
> @@ -1994,17 +1995,17 @@ static void bcm2835_mmal_remove(struct platform_device *pdev)
>  	vchiq_mmal_finalise(instance);
>  }
>  
> -static struct platform_driver bcm2835_camera_driver = {
> +static struct vchiq_driver bcm2835_camera_driver = {
>  	.probe		= bcm2835_mmal_probe,
> -	.remove_new	= bcm2835_mmal_remove,
> +	.remove		= bcm2835_mmal_remove,
>  	.driver		= {
>  		.name	= "bcm2835-camera",
>  	},
>  };
>  
> -module_platform_driver(bcm2835_camera_driver)
> +module_vchiq_driver(bcm2835_camera_driver)
>  
>  MODULE_DESCRIPTION("Broadcom 2835 MMAL video capture");
>  MODULE_AUTHOR("Vincent Sanders");
>  MODULE_LICENSE("GPL");
> -MODULE_ALIAS("platform:bcm2835-camera");
> +MODULE_ALIAS("bcm2835-camera");

Now that you are on your own bus, why do you need the MODULE_ALIAS()
line at all?

thanks,

greg k-h
  
Umang Jain Oct. 9, 2023, 4:20 a.m. UTC | #2
Hi Greg,

Sorry for late reply, as I was traveling and then was on vacation for 
rest of the week.

On 10/5/23 1:34 PM, Greg Kroah-Hartman wrote:
> On Sat, Sep 23, 2023 at 08:01:59PM +0530, Umang Jain wrote:
>> Register the bcm2835-camera with the vchiq_bus_type instead of using
>> platform driver/device.
>>
>> Since we moved away bcm2835-camera from platform driver/device,
>> we have to set the DMA mask explicitly. Set the DMA mask at probe
>> time.
>>
>> Also the VCHIQ firmware doesn't support device enumeration, hence
>> one has to maintain a list of devices to be registered in the interface.
>>
>> Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
>> ---
>>   .../bcm2835-camera/bcm2835-camera.c           | 21 ++++++++++---------
>>   .../interface/vchiq_arm/vchiq_arm.c           | 11 +++++++---
>>   2 files changed, 19 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
>> index fcad5118f3e8..c873eace1437 100644
>> --- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
>> +++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
>> @@ -11,6 +11,7 @@
>>    *          Luke Diamand @ Broadcom
>>    */
>>   
>> +#include <linux/dma-mapping.h>
>>   #include <linux/errno.h>
>>   #include <linux/kernel.h>
>>   #include <linux/module.h>
>> @@ -24,8 +25,8 @@
>>   #include <media/v4l2-event.h>
>>   #include <media/v4l2-common.h>
>>   #include <linux/delay.h>
>> -#include <linux/platform_device.h>
>>   
>> +#include "../interface/vchiq_arm/vchiq_bus.h"
>>   #include "../vchiq-mmal/mmal-common.h"
>>   #include "../vchiq-mmal/mmal-encodings.h"
>>   #include "../vchiq-mmal/mmal-vchiq.h"
>> @@ -1841,7 +1842,7 @@ static struct v4l2_format default_v4l2_format = {
>>   	.fmt.pix.sizeimage = 1024 * 768,
>>   };
>>   
>> -static int bcm2835_mmal_probe(struct platform_device *pdev)
>> +static int bcm2835_mmal_probe(struct vchiq_device *device)
>>   {
>>   	int ret;
>>   	struct bcm2835_mmal_dev *dev;
>> @@ -1852,9 +1853,9 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>>   	unsigned int resolutions[MAX_BCM2835_CAMERAS][2];
>>   	int i;
>>   
>> -	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>> +	ret = dma_set_mask_and_coherent(&device->dev, DMA_BIT_MASK(32));
>>   	if (ret) {
>> -		dev_err(&pdev->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
>> +		dev_err(&device->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
>>   		return ret;
>>   	}
>>   
>> @@ -1902,7 +1903,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>>   						       &camera_instance);
>>   		ret = v4l2_device_register(NULL, &dev->v4l2_dev);
>>   		if (ret) {
>> -			dev_err(&pdev->dev, "%s: could not register V4L2 device: %d\n",
>> +			dev_err(&device->dev, "%s: could not register V4L2 device: %d\n",
>>   				__func__, ret);
>>   			goto free_dev;
>>   		}
>> @@ -1982,7 +1983,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
>>   	return ret;
>>   }
>>   
>> -static void bcm2835_mmal_remove(struct platform_device *pdev)
>> +static void bcm2835_mmal_remove(struct vchiq_device *device)
>>   {
>>   	int camera;
>>   	struct vchiq_mmal_instance *instance = gdev[0]->instance;
>> @@ -1994,17 +1995,17 @@ static void bcm2835_mmal_remove(struct platform_device *pdev)
>>   	vchiq_mmal_finalise(instance);
>>   }
>>   
>> -static struct platform_driver bcm2835_camera_driver = {
>> +static struct vchiq_driver bcm2835_camera_driver = {
>>   	.probe		= bcm2835_mmal_probe,
>> -	.remove_new	= bcm2835_mmal_remove,
>> +	.remove		= bcm2835_mmal_remove,
>>   	.driver		= {
>>   		.name	= "bcm2835-camera",
>>   	},
>>   };
>>   
>> -module_platform_driver(bcm2835_camera_driver)
>> +module_vchiq_driver(bcm2835_camera_driver)
>>   
>>   MODULE_DESCRIPTION("Broadcom 2835 MMAL video capture");
>>   MODULE_AUTHOR("Vincent Sanders");
>>   MODULE_LICENSE("GPL");
>> -MODULE_ALIAS("platform:bcm2835-camera");
>> +MODULE_ALIAS("bcm2835-camera");
> Now that you are on your own bus, why do you need the MODULE_ALIAS()
> line at all?

Because it breaks the module auto-loading support...

If you look at the vchiq_bus patch (3/6) in this series, there is 
vchiq_bus_uevent() which sends a event that includes the MODALIAS.
>
> thanks,
>
> greg k-h
  
Greg Kroah-Hartman Oct. 9, 2023, 10:12 a.m. UTC | #3
On Mon, Oct 09, 2023 at 09:50:29AM +0530, Umang Jain wrote:
> Hi Greg,
> 
> Sorry for late reply, as I was traveling and then was on vacation for rest
> of the week.
> 
> On 10/5/23 1:34 PM, Greg Kroah-Hartman wrote:
> > On Sat, Sep 23, 2023 at 08:01:59PM +0530, Umang Jain wrote:
> > > Register the bcm2835-camera with the vchiq_bus_type instead of using
> > > platform driver/device.
> > > 
> > > Since we moved away bcm2835-camera from platform driver/device,
> > > we have to set the DMA mask explicitly. Set the DMA mask at probe
> > > time.
> > > 
> > > Also the VCHIQ firmware doesn't support device enumeration, hence
> > > one has to maintain a list of devices to be registered in the interface.
> > > 
> > > Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
> > > ---
> > >   .../bcm2835-camera/bcm2835-camera.c           | 21 ++++++++++---------
> > >   .../interface/vchiq_arm/vchiq_arm.c           | 11 +++++++---
> > >   2 files changed, 19 insertions(+), 13 deletions(-)
> > > 
> > > diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> > > index fcad5118f3e8..c873eace1437 100644
> > > --- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> > > +++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
> > > @@ -11,6 +11,7 @@
> > >    *          Luke Diamand @ Broadcom
> > >    */
> > > +#include <linux/dma-mapping.h>
> > >   #include <linux/errno.h>
> > >   #include <linux/kernel.h>
> > >   #include <linux/module.h>
> > > @@ -24,8 +25,8 @@
> > >   #include <media/v4l2-event.h>
> > >   #include <media/v4l2-common.h>
> > >   #include <linux/delay.h>
> > > -#include <linux/platform_device.h>
> > > +#include "../interface/vchiq_arm/vchiq_bus.h"
> > >   #include "../vchiq-mmal/mmal-common.h"
> > >   #include "../vchiq-mmal/mmal-encodings.h"
> > >   #include "../vchiq-mmal/mmal-vchiq.h"
> > > @@ -1841,7 +1842,7 @@ static struct v4l2_format default_v4l2_format = {
> > >   	.fmt.pix.sizeimage = 1024 * 768,
> > >   };
> > > -static int bcm2835_mmal_probe(struct platform_device *pdev)
> > > +static int bcm2835_mmal_probe(struct vchiq_device *device)
> > >   {
> > >   	int ret;
> > >   	struct bcm2835_mmal_dev *dev;
> > > @@ -1852,9 +1853,9 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
> > >   	unsigned int resolutions[MAX_BCM2835_CAMERAS][2];
> > >   	int i;
> > > -	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> > > +	ret = dma_set_mask_and_coherent(&device->dev, DMA_BIT_MASK(32));
> > >   	if (ret) {
> > > -		dev_err(&pdev->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
> > > +		dev_err(&device->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
> > >   		return ret;
> > >   	}
> > > @@ -1902,7 +1903,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
> > >   						       &camera_instance);
> > >   		ret = v4l2_device_register(NULL, &dev->v4l2_dev);
> > >   		if (ret) {
> > > -			dev_err(&pdev->dev, "%s: could not register V4L2 device: %d\n",
> > > +			dev_err(&device->dev, "%s: could not register V4L2 device: %d\n",
> > >   				__func__, ret);
> > >   			goto free_dev;
> > >   		}
> > > @@ -1982,7 +1983,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev)
> > >   	return ret;
> > >   }
> > > -static void bcm2835_mmal_remove(struct platform_device *pdev)
> > > +static void bcm2835_mmal_remove(struct vchiq_device *device)
> > >   {
> > >   	int camera;
> > >   	struct vchiq_mmal_instance *instance = gdev[0]->instance;
> > > @@ -1994,17 +1995,17 @@ static void bcm2835_mmal_remove(struct platform_device *pdev)
> > >   	vchiq_mmal_finalise(instance);
> > >   }
> > > -static struct platform_driver bcm2835_camera_driver = {
> > > +static struct vchiq_driver bcm2835_camera_driver = {
> > >   	.probe		= bcm2835_mmal_probe,
> > > -	.remove_new	= bcm2835_mmal_remove,
> > > +	.remove		= bcm2835_mmal_remove,
> > >   	.driver		= {
> > >   		.name	= "bcm2835-camera",
> > >   	},
> > >   };
> > > -module_platform_driver(bcm2835_camera_driver)
> > > +module_vchiq_driver(bcm2835_camera_driver)
> > >   MODULE_DESCRIPTION("Broadcom 2835 MMAL video capture");
> > >   MODULE_AUTHOR("Vincent Sanders");
> > >   MODULE_LICENSE("GPL");
> > > -MODULE_ALIAS("platform:bcm2835-camera");
> > > +MODULE_ALIAS("bcm2835-camera");
> > Now that you are on your own bus, why do you need the MODULE_ALIAS()
> > line at all?
> 
> Because it breaks the module auto-loading support...

But that's not how auto-loading should work once you have a real bus.

> If you look at the vchiq_bus patch (3/6) in this series, there is
> vchiq_bus_uevent() which sends a event that includes the MODALIAS.

The module alias should be automatically picked out of the
MODULE_DEVICE_TABLE() macro that you should be using for this driver,
you should never have to manually create MODULE_ALIAS() lines.

That's a bad hold-over because the platform driver subsystem can not
handle module aliases on it's own, let's not copy that bad pattern here
as well please.

thanks,

greg k-h
  

Patch

diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
index fcad5118f3e8..c873eace1437 100644
--- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
+++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c
@@ -11,6 +11,7 @@ 
  *          Luke Diamand @ Broadcom
  */
 
+#include <linux/dma-mapping.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -24,8 +25,8 @@ 
 #include <media/v4l2-event.h>
 #include <media/v4l2-common.h>
 #include <linux/delay.h>
-#include <linux/platform_device.h>
 
+#include "../interface/vchiq_arm/vchiq_bus.h"
 #include "../vchiq-mmal/mmal-common.h"
 #include "../vchiq-mmal/mmal-encodings.h"
 #include "../vchiq-mmal/mmal-vchiq.h"
@@ -1841,7 +1842,7 @@  static struct v4l2_format default_v4l2_format = {
 	.fmt.pix.sizeimage = 1024 * 768,
 };
 
-static int bcm2835_mmal_probe(struct platform_device *pdev)
+static int bcm2835_mmal_probe(struct vchiq_device *device)
 {
 	int ret;
 	struct bcm2835_mmal_dev *dev;
@@ -1852,9 +1853,9 @@  static int bcm2835_mmal_probe(struct platform_device *pdev)
 	unsigned int resolutions[MAX_BCM2835_CAMERAS][2];
 	int i;
 
-	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+	ret = dma_set_mask_and_coherent(&device->dev, DMA_BIT_MASK(32));
 	if (ret) {
-		dev_err(&pdev->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
+		dev_err(&device->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
 		return ret;
 	}
 
@@ -1902,7 +1903,7 @@  static int bcm2835_mmal_probe(struct platform_device *pdev)
 						       &camera_instance);
 		ret = v4l2_device_register(NULL, &dev->v4l2_dev);
 		if (ret) {
-			dev_err(&pdev->dev, "%s: could not register V4L2 device: %d\n",
+			dev_err(&device->dev, "%s: could not register V4L2 device: %d\n",
 				__func__, ret);
 			goto free_dev;
 		}
@@ -1982,7 +1983,7 @@  static int bcm2835_mmal_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static void bcm2835_mmal_remove(struct platform_device *pdev)
+static void bcm2835_mmal_remove(struct vchiq_device *device)
 {
 	int camera;
 	struct vchiq_mmal_instance *instance = gdev[0]->instance;
@@ -1994,17 +1995,17 @@  static void bcm2835_mmal_remove(struct platform_device *pdev)
 	vchiq_mmal_finalise(instance);
 }
 
-static struct platform_driver bcm2835_camera_driver = {
+static struct vchiq_driver bcm2835_camera_driver = {
 	.probe		= bcm2835_mmal_probe,
-	.remove_new	= bcm2835_mmal_remove,
+	.remove		= bcm2835_mmal_remove,
 	.driver		= {
 		.name	= "bcm2835-camera",
 	},
 };
 
-module_platform_driver(bcm2835_camera_driver)
+module_vchiq_driver(bcm2835_camera_driver)
 
 MODULE_DESCRIPTION("Broadcom 2835 MMAL video capture");
 MODULE_AUTHOR("Vincent Sanders");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:bcm2835-camera");
+MODULE_ALIAS("bcm2835-camera");
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index 9388859b9b56..886025f0a452 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -67,8 +67,13 @@  int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
 DEFINE_SPINLOCK(msg_queue_spinlock);
 struct vchiq_state g_state;
 
-static struct platform_device *bcm2835_camera;
 static struct platform_device *bcm2835_audio;
+/*
+ * The devices implemented in the VCHIQ firmware are not discoverable,
+ * so we need to maintain a list of them in order to register them with
+ * the interface.
+ */
+static struct vchiq_device *bcm2835_camera;
 
 struct vchiq_drvdata {
 	const unsigned int cache_line_size;
@@ -1840,8 +1845,8 @@  static int vchiq_probe(struct platform_device *pdev)
 		goto error_exit;
 	}
 
-	bcm2835_camera = vchiq_register_child(pdev, "bcm2835-camera");
 	bcm2835_audio = vchiq_register_child(pdev, "bcm2835_audio");
+	bcm2835_camera = vchiq_device_register(&pdev->dev, "bcm2835-camera");
 
 	return 0;
 
@@ -1854,7 +1859,7 @@  static int vchiq_probe(struct platform_device *pdev)
 static void vchiq_remove(struct platform_device *pdev)
 {
 	platform_device_unregister(bcm2835_audio);
-	platform_device_unregister(bcm2835_camera);
+	vchiq_device_unregister(bcm2835_camera);
 	vchiq_debugfs_deinit();
 	vchiq_deregister_chrdev();
 }