Commit 4aaec3ea authored by David Ellingsworth's avatar David Ellingsworth Committed by Mauro Carvalho Chehab
Browse files

V4L/DVB (9034): With the recent patch to v4l2 titled "v4l2: use register_chrdev_region 



instead of register_chrdev", the internal reference count is no longer
necessary in order to free the internal stk_webcam struct. This patch
removes the reference counter from the stk_webcam struct and frees the
struct via the video_device release callback. It also fixes an
associated bug in stk_camera_probe which could result from
video_unregister_device being called before video_register_device.
Lastly, it simplifies access to the stk_webcam struct in several
places. This patch should apply cleanly against the "working" branch
of the v4l-dvb git repository.

This patch is identical to the patch I sent a couple of months back
titled "stk-webcam: Fix video_device handling" except that it has been
rebased against current modifications to stk-webcam and it no longer
depends on any other outstanding patches.

Acked-by: default avatarJaime Velasco Juan <jsagarribay@gmail.com>
Signed-off-by: default avatarDavid Ellingsworth <david@identd.dyndns.org>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
parent 714b9a1e

drivers/media/video/stk-webcam.c

+23 −61
Original line number Diff line number Diff line
@@ -65,22 +65,6 @@ static struct usb_device_id stkwebcam_table[] = { 
};

MODULE_DEVICE_TABLE(usb, stkwebcam_table);



static void stk_camera_cleanup(struct kref *kref)

{

	struct stk_camera *dev = to_stk_camera(kref);



	STK_INFO("Syntek USB2.0 Camera release resources"

		" video device /dev/video%d\n", dev->vdev.minor);

	video_unregister_device(&dev->vdev);

	video_set_drvdata(&dev->vdev, NULL);



	if (dev->sio_bufs != NULL || dev->isobufs != NULL)

		STK_ERROR("We are leaking memory\n");

	usb_put_intf(dev->interface);

	kfree(dev);

}





/*

 * Basic stuff

 */
@@ -694,8 +678,7 @@ static int v4l_stk_open(struct inode *inode, struct file *fp) 
		unlock_kernel();

		return -ENXIO;

	}

	fp->private_data = vdev;

	kref_get(&dev->kref);

	fp->private_data = dev;

	usb_autopm_get_interface(dev->interface);

	unlock_kernel();
@@ -704,23 +687,10 @@ static int v4l_stk_open(struct inode *inode, struct file *fp) 


static int v4l_stk_release(struct inode *inode, struct file *fp)

{

	struct stk_camera *dev;

	struct video_device *vdev;



	vdev = video_devdata(fp);

	if (vdev == NULL) {

		STK_ERROR("v4l_release called w/o video devdata\n");

		return -EFAULT;

	}

	dev = vdev_to_camera(vdev);

	if (dev == NULL) {

		STK_ERROR("v4l_release called on removed device\n");

		return -ENODEV;

	}

	struct stk_camera *dev = fp->private_data;



	if (dev->owner != fp) {

		usb_autopm_put_interface(dev->interface);

		kref_put(&dev->kref, stk_camera_cleanup);

		return 0;

	}
@@ -731,7 +701,6 @@ static int v4l_stk_release(struct inode *inode, struct file *fp) 
	dev->owner = NULL;



	usb_autopm_put_interface(dev->interface);

	kref_put(&dev->kref, stk_camera_cleanup);



	return 0;

}
@@ -742,14 +711,8 @@ static ssize_t v4l_stk_read(struct file *fp, char __user *buf, 
	int i;

	int ret;

	unsigned long flags;

	struct stk_camera *dev;

	struct video_device *vdev;

	struct stk_sio_buffer *sbuf;



	vdev = video_devdata(fp);

	if (vdev == NULL)

		return -EFAULT;

	dev = vdev_to_camera(vdev);

	struct stk_camera *dev = fp->private_data;



	if (dev == NULL)

		return -EIO;
@@ -808,15 +771,8 @@ static ssize_t v4l_stk_read(struct file *fp, char __user *buf, 


static unsigned int v4l_stk_poll(struct file *fp, poll_table *wait)

{

	struct stk_camera *dev;

	struct video_device *vdev;



	vdev = video_devdata(fp);



	if (vdev == NULL)

		return -EFAULT;

	struct stk_camera *dev = fp->private_data;



	dev = vdev_to_camera(vdev);

	if (dev == NULL)

		return -ENODEV;
@@ -854,16 +810,12 @@ static int v4l_stk_mmap(struct file *fp, struct vm_area_struct *vma) 
	unsigned int i;

	int ret;

	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;

	struct stk_camera *dev;

	struct video_device *vdev;

	struct stk_camera *dev = fp->private_data;

	struct stk_sio_buffer *sbuf = NULL;



	if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED))

		return -EINVAL;



	vdev = video_devdata(fp);

	dev = vdev_to_camera(vdev);



	for (i = 0; i < dev->n_sbufs; i++) {

		if (dev->sio_bufs[i].v4lbuf.m.offset == offset) {

			sbuf = dev->sio_bufs + i;
@@ -1359,6 +1311,12 @@ static const struct v4l2_ioctl_ops v4l_stk_ioctl_ops = { 


static void stk_v4l_dev_release(struct video_device *vd)

{

	struct stk_camera *dev = vdev_to_camera(vd);



	if (dev->sio_bufs != NULL || dev->isobufs != NULL)

		STK_ERROR("We are leaking memory\n");

	usb_put_intf(dev->interface);

	kfree(dev);

}



static struct video_device stk_v4l_data = {
@@ -1379,7 +1337,6 @@ static int stk_register_video_device(struct stk_camera *dev) 
	dev->vdev = stk_v4l_data;

	dev->vdev.debug = debug;

	dev->vdev.parent = &dev->interface->dev;

	video_set_drvdata(&dev->vdev, dev);

	err = video_register_device(&dev->vdev, VFL_TYPE_GRABBER, -1);

	if (err)

		STK_ERROR("v4l registration failed\n");
@@ -1396,7 +1353,7 @@ static int stk_camera_probe(struct usb_interface *interface, 
		const struct usb_device_id *id)

{

	int i;

	int err;

	int err = 0;



	struct stk_camera *dev = NULL;

	struct usb_device *udev = interface_to_usbdev(interface);
@@ -1409,7 +1366,6 @@ static int stk_camera_probe(struct usb_interface *interface, 
		return -ENOMEM;

	}



	kref_init(&dev->kref);

	spin_lock_init(&dev->spinlock);

	init_waitqueue_head(&dev->wait_frame);
@@ -1442,8 +1398,8 @@ static int stk_camera_probe(struct usb_interface *interface, 
	}

	if (!dev->isoc_ep) {

		STK_ERROR("Could not find isoc-in endpoint");

		kref_put(&dev->kref, stk_camera_cleanup);

		return -ENODEV;

		err = -ENODEV;

		goto error;

	}

	dev->vsettings.brightness = 0x7fff;

	dev->vsettings.palette = V4L2_PIX_FMT_RGB565;
@@ -1457,14 +1413,17 @@ static int stk_camera_probe(struct usb_interface *interface, 


	err = stk_register_video_device(dev);

	if (err) {

		kref_put(&dev->kref, stk_camera_cleanup);

		return err;

		goto error;

	}



	stk_create_sysfs_files(&dev->vdev);

	usb_autopm_enable(dev->interface);



	return 0;



error:

	kfree(dev);

	return err;

}



static void stk_camera_disconnect(struct usb_interface *interface)
@@ -1477,7 +1436,10 @@ static void stk_camera_disconnect(struct usb_interface *interface) 
	wake_up_interruptible(&dev->wait_frame);

	stk_remove_sysfs_files(&dev->vdev);



	kref_put(&dev->kref, stk_camera_cleanup);

	STK_INFO("Syntek USB2.0 Camera release resources"

		"video device /dev/video%d\n", dev->vdev.minor);



	video_unregister_device(&dev->vdev);

}



#ifdef CONFIG_PM

drivers/media/video/stk-webcam.h

+0 −2
Original line number Diff line number Diff line
@@ -99,7 +99,6 @@ struct stk_camera { 


	u8 isoc_ep;



	struct kref kref;

	/* Not sure if this is right */

	atomic_t urbs_used;
@@ -121,7 +120,6 @@ struct stk_camera { 
	unsigned sequence;

};



#define to_stk_camera(d) container_of(d, struct stk_camera, kref)

#define vdev_to_camera(d) container_of(d, struct stk_camera, vdev)



void stk_camera_delete(struct kref *);

CRA Git | Maintained and supported by SUSTech CRA and CCSE