UVC driver used to have partial no-mmu arch support, but it's removed by
commit c29fcff3daafbf46d64a543c1950bbd206ad8c1c.
This patch added them back and expanded to fully support no-mmu arch, so that
uvc cameras can be used on no-mmu platforms like Blackfin.
Signed-off-by: Bob Liu <[email protected]>
---
drivers/media/video/uvc/uvc_v4l2.c | 36 ++++++++++++++++++++++++++++++++++++
drivers/media/video/v4l2-dev.c | 18 ++++++++++++++++++
drivers/usb/gadget/uvc_queue.c | 15 +++++++++++++++
include/media/v4l2-dev.h | 2 ++
4 files changed, 71 insertions(+), 0 deletions(-)
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 9005a8d..2413ec9 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -1081,6 +1081,39 @@ static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
return uvc_queue_poll(&stream->queue, file, wait);
}
+#ifndef CONFIG_MMU
+static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
+ unsigned long addr, unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
+ struct uvc_streaming *stream = handle->stream;
+ struct uvc_video_queue *queue = &stream->queue;
+ struct uvc_buffer *uninitialized_var(buffer);
+ unsigned int i;
+ int ret = 0;
+
+ mutex_lock(&queue->mutex);
+ for (i = 0; i < queue->count; ++i) {
+ buffer = &queue->buffer[i];
+ if ((buffer->buf.m.offset >> PAGE_SHIFT) == pgoff)
+ break;
+ }
+
+ if (i == queue->count ||
+ PAGE_ALIGN(len) != queue->buf_size) {
+ ret = -EINVAL;
+ goto done;
+ }
+
+ addr = (unsigned long)queue->mem + buffer->buf.m.offset;
+ ret = addr;
+done:
+ mutex_unlock(&queue->mutex);
+ return ret;
+}
+#endif
+
const struct v4l2_file_operations uvc_fops = {
.owner = THIS_MODULE,
.open = uvc_v4l2_open,
@@ -1089,5 +1122,8 @@ const struct v4l2_file_operations uvc_fops = {
.read = uvc_v4l2_read,
.mmap = uvc_v4l2_mmap,
.poll = uvc_v4l2_poll,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = uvc_v4l2_get_unmapped_area,
+#endif
};
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index 341764a..bdcf413 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -299,6 +299,21 @@ static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm)
return ret;
}
+#ifndef CONFIG_MMU
+static unsigned long v4l2_get_unmapped_area(struct file *filp,
+ unsigned long addr, unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ struct video_device *vdev = video_devdata(filp);
+
+ if (!vdev->fops->get_unmapped_area)
+ return -ENOSYS;
+ if (!video_is_registered(vdev))
+ return -ENODEV;
+ return vdev->fops->get_unmapped_area(filp, addr, len, pgoff, flags);
+}
+#endif
+
/* Override for the open function */
static int v4l2_open(struct inode *inode, struct file *filp)
{
@@ -362,6 +377,9 @@ static const struct file_operations v4l2_fops = {
.write = v4l2_write,
.open = v4l2_open,
.mmap = v4l2_mmap,
+#ifndef CONFIG_MMU
+ .get_unmapped_area = v4l2_get_unmapped_area,
+#endif
.unlocked_ioctl = v4l2_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = v4l2_compat_ioctl32,
diff --git a/drivers/usb/gadget/uvc_queue.c b/drivers/usb/gadget/uvc_queue.c
index f7395ac..24378fb 100644
--- a/drivers/usb/gadget/uvc_queue.c
+++ b/drivers/usb/gadget/uvc_queue.c
@@ -431,6 +431,7 @@ uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
break;
}
+#ifdef CONFIG_MMU
if (i == queue->count || size != queue->buf_size) {
ret = -EINVAL;
goto done;
@@ -452,6 +453,20 @@ uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
addr += PAGE_SIZE;
size -= PAGE_SIZE;
}
+#else
+ if (i == queue->count ||
+ PAGE_ALIGN(size) != queue->buf_size) {
+ ret = -EINVAL;
+ goto done;
+ }
+
+ /* documentation/nommu-mmap.txt */
+ vma->vm_flags |= VM_IO | VM_MAYSHARE;
+
+ addr = (unsigned long)queue->mem + buffer->buf.m.offset;
+ vma->vm_start = addr;
+ vma->vm_end = addr + queue->buf_size;
+#endif
vma->vm_ops = &uvc_vm_ops;
vma->vm_private_data = buffer;
diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
index 15802a0..a0af49a 100644
--- a/include/media/v4l2-dev.h
+++ b/include/media/v4l2-dev.h
@@ -42,6 +42,8 @@ struct v4l2_file_operations {
long (*ioctl) (struct file *, unsigned int, unsigned long);
long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
int (*mmap) (struct file *, struct vm_area_struct *);
+ unsigned long (*get_unmapped_area) (struct file *, unsigned long,
+ unsigned long, unsigned long, unsigned long);
int (*open) (struct file *);
int (*release) (struct file *);
};
--
1.6.3.3
Hi Bob,
Thanks for the patch.
On Thursday 10 March 2011 03:44:37 Bob Liu wrote:
> UVC driver used to have partial no-mmu arch support, but it's removed by
> commit c29fcff3daafbf46d64a543c1950bbd206ad8c1c.
>
> This patch added them back and expanded to fully support no-mmu arch, so
> that uvc cameras can be used on no-mmu platforms like Blackfin.
>
> Signed-off-by: Bob Liu <[email protected]>
> ---
> drivers/media/video/uvc/uvc_v4l2.c | 36
> ++++++++++++++++++++++++++++++++++++ drivers/media/video/v4l2-dev.c |
> 18 ++++++++++++++++++
> drivers/usb/gadget/uvc_queue.c | 15 +++++++++++++++
> include/media/v4l2-dev.h | 2 ++
> 4 files changed, 71 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/media/video/uvc/uvc_v4l2.c
> b/drivers/media/video/uvc/uvc_v4l2.c index 9005a8d..2413ec9 100644
> --- a/drivers/media/video/uvc/uvc_v4l2.c
> +++ b/drivers/media/video/uvc/uvc_v4l2.c
> @@ -1081,6 +1081,39 @@ static unsigned int uvc_v4l2_poll(struct file *file,
> poll_table *wait) return uvc_queue_poll(&stream->queue, file, wait);
> }
>
> +#ifndef CONFIG_MMU
> +static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
> + unsigned long addr, unsigned long len, unsigned long pgoff,
> + unsigned long flags)
> +{
> + struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
> + struct uvc_streaming *stream = handle->stream;
> + struct uvc_video_queue *queue = &stream->queue;
> + struct uvc_buffer *uninitialized_var(buffer);
> + unsigned int i;
> + int ret = 0;
> +
> + mutex_lock(&queue->mutex);
> + for (i = 0; i < queue->count; ++i) {
> + buffer = &queue->buffer[i];
> + if ((buffer->buf.m.offset >> PAGE_SHIFT) == pgoff)
> + break;
> + }
> +
> + if (i == queue->count ||
> + PAGE_ALIGN(len) != queue->buf_size) {
> + ret = -EINVAL;
> + goto done;
> + }
> +
> + addr = (unsigned long)queue->mem + buffer->buf.m.offset;
> + ret = addr;
> +done:
> + mutex_unlock(&queue->mutex);
> + return ret;
> +}
> +#endif
> +
Could you move the core of this function to uvc_queue.c ? Something like
unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
unsigned long addr, unsigned long len, unsigned long pgoff,
unsigned long flags),
static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
unsigned long addr, unsigned long len, unsigned long pgoff,
unsigned long flags)
{
struct uvc_fh *handle = (struct uvc_fh *)file->private_data;
struct uvc_streaming *stream = handle->stream;
return uvc_queue_get_unmapped_area(queue, addr, len, pgoff, flags);
}
> diff --git a/drivers/usb/gadget/uvc_queue.c
> b/drivers/usb/gadget/uvc_queue.c index f7395ac..24378fb 100644
> --- a/drivers/usb/gadget/uvc_queue.c
> +++ b/drivers/usb/gadget/uvc_queue.c
> @@ -431,6 +431,7 @@ uvc_queue_mmap(struct uvc_video_queue *queue, struct
> vm_area_struct *vma) break;
> }
>
> +#ifdef CONFIG_MMU
> if (i == queue->count || size != queue->buf_size) {
> ret = -EINVAL;
> goto done;
> @@ -452,6 +453,20 @@ uvc_queue_mmap(struct uvc_video_queue *queue, struct
> vm_area_struct *vma) addr += PAGE_SIZE;
> size -= PAGE_SIZE;
> }
> +#else
> + if (i == queue->count ||
> + PAGE_ALIGN(size) != queue->buf_size) {
> + ret = -EINVAL;
> + goto done;
> + }
> +
> + /* documentation/nommu-mmap.txt */
> + vma->vm_flags |= VM_IO | VM_MAYSHARE;
> +
> + addr = (unsigned long)queue->mem + buffer->buf.m.offset;
> + vma->vm_start = addr;
> + vma->vm_end = addr + queue->buf_size;
> +#endif
>
> vma->vm_ops = &uvc_vm_ops;
> vma->vm_private_data = buffer;
Note that uvc_queue.c will be replaced by videobuf2 in the (near ?) future.
NOMMU support will thus be removed once again. If you want to keep it, you
should add a patch to videobuf2 to implement NOMMU support there.
--
Regards,
Laurent Pinchart