summaryrefslogtreecommitdiff
path: root/drivers/media/video/zc0301/zc0301_core.c
diff options
context:
space:
mode:
authorLuca Risolia <luca.risolia@studio.unibo.it>2007-06-13 15:11:15 -0300
committerMauro Carvalho Chehab <mchehab@infradead.org>2007-07-18 14:24:09 -0300
commit4052fcc7ba32ebd54cc907991cb855d909ce9d1c (patch)
tree2f1049c2f26d1067fa4e15d74392013c2c091505 /drivers/media/video/zc0301/zc0301_core.c
parent3b2ae0be9e246974db65a5bf4ccd2de328f3dede (diff)
V4L/DVB (5767): ZC0301 driver updates
- Make the driver depend on V4L2 only (KConfig) - Better and safe locking mechanism of the device structure on open(), close() and disconnect() - Use kref for handling device deallocation - Generic cleanups Signed-off-by: Luca Risolia <luca.risolia@studio.unibo.it> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers/media/video/zc0301/zc0301_core.c')
-rw-r--r--drivers/media/video/zc0301/zc0301_core.c147
1 files changed, 75 insertions, 72 deletions
diff --git a/drivers/media/video/zc0301/zc0301_core.c b/drivers/media/video/zc0301/zc0301_core.c
index f1120551c70c..703b741e46df 100644
--- a/drivers/media/video/zc0301/zc0301_core.c
+++ b/drivers/media/video/zc0301/zc0301_core.c
@@ -49,11 +49,11 @@
#define ZC0301_MODULE_NAME "V4L2 driver for ZC0301[P] " \
"Image Processor and Control Chip"
-#define ZC0301_MODULE_AUTHOR "(C) 2006 Luca Risolia"
+#define ZC0301_MODULE_AUTHOR "(C) 2006-2007 Luca Risolia"
#define ZC0301_AUTHOR_EMAIL "<luca.risolia@studio.unibo.it>"
#define ZC0301_MODULE_LICENSE "GPL"
-#define ZC0301_MODULE_VERSION "1:1.07"
-#define ZC0301_MODULE_VERSION_CODE KERNEL_VERSION(1, 1, 7)
+#define ZC0301_MODULE_VERSION "1:1.10"
+#define ZC0301_MODULE_VERSION_CODE KERNEL_VERSION(1, 1, 10)
/*****************************************************************************/
@@ -573,7 +573,8 @@ static int zc0301_init(struct zc0301_device* cam)
int err = 0;
if (!(cam->state & DEV_INITIALIZED)) {
- init_waitqueue_head(&cam->open);
+ mutex_init(&cam->open_mutex);
+ init_waitqueue_head(&cam->wait_open);
qctrl = s->qctrl;
rect = &(s->cropcap.defrect);
cam->compression.quality = ZC0301_COMPRESSION_QUALITY;
@@ -634,59 +635,73 @@ static int zc0301_init(struct zc0301_device* cam)
return 0;
}
+/*****************************************************************************/
-static void zc0301_release_resources(struct zc0301_device* cam)
+static void zc0301_release_resources(struct kref *kref)
{
+ struct zc0301_device *cam = container_of(kref, struct zc0301_device,
+ kref);
DBG(2, "V4L2 device /dev/video%d deregistered", cam->v4ldev->minor);
video_set_drvdata(cam->v4ldev, NULL);
video_unregister_device(cam->v4ldev);
+ usb_put_dev(cam->usbdev);
kfree(cam->control_buffer);
+ kfree(cam);
}
-/*****************************************************************************/
static int zc0301_open(struct inode* inode, struct file* filp)
{
struct zc0301_device* cam;
int err = 0;
- /*
- This is the only safe way to prevent race conditions with
- disconnect
- */
- if (!down_read_trylock(&zc0301_disconnect))
+ if (!down_read_trylock(&zc0301_dev_lock))
return -ERESTARTSYS;
cam = video_get_drvdata(video_devdata(filp));
- if (mutex_lock_interruptible(&cam->dev_mutex)) {
- up_read(&zc0301_disconnect);
+ if (wait_for_completion_interruptible(&cam->probe)) {
+ up_read(&zc0301_dev_lock);
return -ERESTARTSYS;
}
+ kref_get(&cam->kref);
+
+ if (mutex_lock_interruptible(&cam->open_mutex)) {
+ kref_put(&cam->kref, zc0301_release_resources);
+ up_read(&zc0301_dev_lock);
+ return -ERESTARTSYS;
+ }
+
+ if (cam->state & DEV_DISCONNECTED) {
+ DBG(1, "Device not present");
+ err = -ENODEV;
+ goto out;
+ }
+
if (cam->users) {
DBG(2, "Device /dev/video%d is busy...", cam->v4ldev->minor);
+ DBG(3, "Simultaneous opens are not supported");
if ((filp->f_flags & O_NONBLOCK) ||
(filp->f_flags & O_NDELAY)) {
err = -EWOULDBLOCK;
goto out;
}
- mutex_unlock(&cam->dev_mutex);
- err = wait_event_interruptible_exclusive(cam->open,
- cam->state & DEV_DISCONNECTED
+ DBG(2, "A blocking open() has been requested. Wait for the "
+ "device to be released...");
+ up_read(&zc0301_dev_lock);
+ err = wait_event_interruptible_exclusive(cam->wait_open,
+ (cam->state & DEV_DISCONNECTED)
|| !cam->users);
- if (err) {
- up_read(&zc0301_disconnect);
- return err;
- }
+ down_read(&zc0301_dev_lock);
+ if (err)
+ goto out;
if (cam->state & DEV_DISCONNECTED) {
- up_read(&zc0301_disconnect);
- return -ENODEV;
+ err = -ENODEV;
+ goto out;
}
- mutex_lock(&cam->dev_mutex);
}
-
if (cam->state & DEV_MISCONFIGURED) {
err = zc0301_init(cam);
if (err) {
@@ -711,36 +726,32 @@ static int zc0301_open(struct inode* inode, struct file* filp)
DBG(3, "Video device /dev/video%d is open", cam->v4ldev->minor);
out:
- mutex_unlock(&cam->dev_mutex);
- up_read(&zc0301_disconnect);
+ mutex_unlock(&cam->open_mutex);
+ if (err)
+ kref_put(&cam->kref, zc0301_release_resources);
+ up_read(&zc0301_dev_lock);
return err;
}
static int zc0301_release(struct inode* inode, struct file* filp)
{
- struct zc0301_device* cam = video_get_drvdata(video_devdata(filp));
+ struct zc0301_device* cam;
- mutex_lock(&cam->dev_mutex); /* prevent disconnect() to be called */
+ down_write(&zc0301_dev_lock);
- zc0301_stop_transfer(cam);
+ cam = video_get_drvdata(video_devdata(filp));
+ zc0301_stop_transfer(cam);
zc0301_release_buffers(cam);
-
- if (cam->state & DEV_DISCONNECTED) {
- zc0301_release_resources(cam);
- usb_put_dev(cam->usbdev);
- mutex_unlock(&cam->dev_mutex);
- kfree(cam);
- return 0;
- }
-
cam->users--;
- wake_up_interruptible_nr(&cam->open, 1);
+ wake_up_interruptible_nr(&cam->wait_open, 1);
DBG(3, "Video device /dev/video%d closed", cam->v4ldev->minor);
- mutex_unlock(&cam->dev_mutex);
+ kref_put(&cam->kref, zc0301_release_resources);
+
+ up_write(&zc0301_dev_lock);
return 0;
}
@@ -775,7 +786,7 @@ zc0301_read(struct file* filp, char __user * buf, size_t count, loff_t* f_pos)
DBG(3, "Close and open the device again to choose the read "
"method");
mutex_unlock(&cam->fileop_mutex);
- return -EINVAL;
+ return -EBUSY;
}
if (cam->io == IO_NONE) {
@@ -953,7 +964,12 @@ static int zc0301_mmap(struct file* filp, struct vm_area_struct *vma)
return -EIO;
}
- if (cam->io != IO_MMAP || !(vma->vm_flags & VM_WRITE) ||
+ if (!(vma->vm_flags & (VM_WRITE | VM_READ))) {
+ mutex_unlock(&cam->fileop_mutex);
+ return -EACCES;
+ }
+
+ if (cam->io != IO_MMAP ||
size != PAGE_ALIGN(cam->frame[0].buf.length)) {
mutex_unlock(&cam->fileop_mutex);
return -EINVAL;
@@ -984,7 +1000,6 @@ static int zc0301_mmap(struct file* filp, struct vm_area_struct *vma)
vma->vm_ops = &zc0301_vm_ops;
vma->vm_private_data = &cam->frame[i];
-
zc0301_vm_open(vma);
mutex_unlock(&cam->fileop_mutex);
@@ -1211,7 +1226,7 @@ zc0301_vidioc_s_crop(struct zc0301_device* cam, void __user * arg)
if (cam->frame[i].vma_use_count) {
DBG(3, "VIDIOC_S_CROP failed. "
"Unmap the buffers first.");
- return -EINVAL;
+ return -EBUSY;
}
if (!s->set_crop) {
@@ -1434,7 +1449,7 @@ zc0301_vidioc_try_s_fmt(struct zc0301_device* cam, unsigned int cmd,
if (cam->frame[i].vma_use_count) {
DBG(3, "VIDIOC_S_FMT failed. "
"Unmap the buffers first.");
- return -EINVAL;
+ return -EBUSY;
}
if (cam->stream == STREAM_ON)
@@ -1544,14 +1559,14 @@ zc0301_vidioc_reqbufs(struct zc0301_device* cam, void __user * arg)
if (cam->io == IO_READ) {
DBG(3, "Close and open the device again to choose the mmap "
"I/O method");
- return -EINVAL;
+ return -EBUSY;
}
for (i = 0; i < cam->nbuffers; i++)
if (cam->frame[i].vma_use_count) {
DBG(3, "VIDIOC_REQBUFS failed. "
"Previous buffers are still mapped.");
- return -EINVAL;
+ return -EBUSY;
}
if (cam->stream == STREAM_ON)
@@ -1699,9 +1714,6 @@ zc0301_vidioc_streamon(struct zc0301_device* cam, void __user * arg)
if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE || cam->io != IO_MMAP)
return -EINVAL;
- if (list_empty(&cam->inqueue))
- return -EINVAL;
-
cam->stream = STREAM_ON;
DBG(3, "Stream on");
@@ -1949,8 +1961,6 @@ zc0301_usb_probe(struct usb_interface* intf, const struct usb_device_id* id)
goto fail;
}
- mutex_init(&cam->dev_mutex);
-
DBG(2, "ZC0301[P] Image Processor and Control Chip detected "
"(vid/pid 0x%04X:0x%04X)",id->idVendor, id->idProduct);
@@ -1982,7 +1992,7 @@ zc0301_usb_probe(struct usb_interface* intf, const struct usb_device_id* id)
cam->v4ldev->release = video_device_release;
video_set_drvdata(cam->v4ldev, cam);
- mutex_lock(&cam->dev_mutex);
+ init_completion(&cam->probe);
err = video_register_device(cam->v4ldev, VFL_TYPE_GRABBER,
video_nr[dev_nr]);
@@ -1992,7 +2002,7 @@ zc0301_usb_probe(struct usb_interface* intf, const struct usb_device_id* id)
DBG(1, "Free /dev/videoX node not found");
video_nr[dev_nr] = -1;
dev_nr = (dev_nr < ZC0301_MAX_DEVICES-1) ? dev_nr+1 : 0;
- mutex_unlock(&cam->dev_mutex);
+ complete_all(&cam->probe);
goto fail;
}
@@ -2004,8 +2014,10 @@ zc0301_usb_probe(struct usb_interface* intf, const struct usb_device_id* id)
dev_nr = (dev_nr < ZC0301_MAX_DEVICES-1) ? dev_nr+1 : 0;
usb_set_intfdata(intf, cam);
+ kref_init(&cam->kref);
+ usb_get_dev(cam->usbdev);
- mutex_unlock(&cam->dev_mutex);
+ complete_all(&cam->probe);
return 0;
@@ -2022,40 +2034,31 @@ fail:
static void zc0301_usb_disconnect(struct usb_interface* intf)
{
- struct zc0301_device* cam = usb_get_intfdata(intf);
-
- if (!cam)
- return;
+ struct zc0301_device* cam;
- down_write(&zc0301_disconnect);
+ down_write(&zc0301_dev_lock);
- mutex_lock(&cam->dev_mutex);
+ cam = usb_get_intfdata(intf);
DBG(2, "Disconnecting %s...", cam->v4ldev->name);
- wake_up_interruptible_all(&cam->open);
-
if (cam->users) {
DBG(2, "Device /dev/video%d is open! Deregistration and "
- "memory deallocation are deferred on close.",
+ "memory deallocation are deferred.",
cam->v4ldev->minor);
cam->state |= DEV_MISCONFIGURED;
zc0301_stop_transfer(cam);
cam->state |= DEV_DISCONNECTED;
wake_up_interruptible(&cam->wait_frame);
wake_up(&cam->wait_stream);
- usb_get_dev(cam->usbdev);
- } else {
+ } else
cam->state |= DEV_DISCONNECTED;
- zc0301_release_resources(cam);
- }
- mutex_unlock(&cam->dev_mutex);
+ wake_up_interruptible_all(&cam->wait_open);
- if (!cam->users)
- kfree(cam);
+ kref_put(&cam->kref, zc0301_release_resources);
- up_write(&zc0301_disconnect);
+ up_write(&zc0301_dev_lock);
}