diff mbox series

[v5,02/12] media: uvcvideo: Allow more that one asyc_ctrl

Message ID 20201221164819.792019-3-ribalda@chromium.org (mailing list archive)
State New, archived
Headers show
Series Show privacy_gpio as a v4l2_ctrl | expand

Commit Message

Ricardo Ribalda Dec. 21, 2020, 4:48 p.m. UTC 
The current implementation allocates memory for only one async_control.
If we get a second event before we have processed the previous one, the
old one gets lost.

Introduce a dynamic memory allocation and a list to handle the
async_controls.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
 drivers/media/usb/uvc/uvc_ctrl.c | 49 ++++++++++++++++++++++++++------
 drivers/media/usb/uvc/uvcvideo.h | 19 ++++++++-----
 2 files changed, 52 insertions(+), 16 deletions(-)

Comments

Laurent Pinchart Dec. 22, 2020, 8:07 a.m. UTC | #1 
Hi Ricardo,

Thank you for the patch.

On Mon, Dec 21, 2020 at 05:48:09PM +0100, Ricardo Ribalda wrote:
> The current implementation allocates memory for only one async_control.
> If we get a second event before we have processed the previous one, the
> old one gets lost.
> 
> Introduce a dynamic memory allocation and a list to handle the
> async_controls.

Thinking some more about this, do we need to go through the work queue
at all for GPIO-based events ? Could the part of
uvc_ctrl_status_event_work() before the URB resubmission be moved to
another function, which would be called directly by the GPIO threaded
IRQ handler ?

> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
>  drivers/media/usb/uvc/uvc_ctrl.c | 49 ++++++++++++++++++++++++++------
>  drivers/media/usb/uvc/uvcvideo.h | 19 ++++++++-----
>  2 files changed, 52 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index aa18dcdf8165..69b2fc6ce12c 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1275,11 +1275,9 @@ static void uvc_ctrl_send_slave_event(struct uvc_video_chain *chain,
>  	uvc_ctrl_send_event(chain, handle, ctrl, mapping, val, changes);
>  }
>  
> -static void uvc_ctrl_status_event_work(struct work_struct *work)
> +static void __uvc_ctrl_status_event_work(struct uvc_device *dev,
> +					 struct uvc_ctrl_work *w)
>  {
> -	struct uvc_device *dev = container_of(work, struct uvc_device,
> -					      async_ctrl.work);
> -	struct uvc_ctrl_work *w = &dev->async_ctrl;
>  	struct uvc_video_chain *chain = w->chain;
>  	struct uvc_control_mapping *mapping;
>  	struct uvc_control *ctrl = w->ctrl;
> @@ -1321,23 +1319,54 @@ static void uvc_ctrl_status_event_work(struct work_struct *work)
>  			   ret);
>  }
>  
> +static void uvc_ctrl_status_event_work(struct work_struct *work)
> +{
> +	struct uvc_device *dev = container_of(work, struct uvc_device,
> +					      async_ctrl_work);
> +	struct uvc_ctrl_work *w;
> +
> +	do {
> +		mutex_lock(&dev->async_ctrl_lock);
> +		w = list_first_entry_or_null(&dev->async_ctrl_list,
> +					     struct uvc_ctrl_work,
> +					     list);
> +		if (w)
> +			list_del(&w->list);
> +		mutex_unlock(&dev->async_ctrl_lock);
> +
> +		if (!w)
> +			return;
> +
> +		__uvc_ctrl_status_event_work(dev, w);
> +		kfree(w);
> +	} while (w);
> +}
> +
>  bool uvc_ctrl_status_event(struct urb *urb, struct uvc_video_chain *chain,
>  			   struct uvc_control *ctrl, const u8 *data)
>  {
>  	struct uvc_device *dev = chain->dev;
> -	struct uvc_ctrl_work *w = &dev->async_ctrl;
> +	struct uvc_ctrl_work *w;
>  
>  	if (list_empty(&ctrl->info.mappings)) {
>  		ctrl->handle = NULL;
>  		return false;
>  	}
>  
> +	w = kzalloc(sizeof(*w), GFP_KERNEL);
> +	if (WARN(!w, "Not enough memory to trigger uvc event"))
> +		return false;
> +
>  	memcpy(w->data, data, ctrl->info.size);
>  	w->urb = urb;
>  	w->chain = chain;
>  	w->ctrl = ctrl;
>  
> -	schedule_work(&w->work);
> +	mutex_lock(&dev->async_ctrl_lock);
> +	list_add_tail(&w->list, &dev->async_ctrl_list);
> +	mutex_unlock(&dev->async_ctrl_lock);
> +
> +	schedule_work(&dev->async_ctrl_work);
>  
>  	return true;
>  }
> @@ -2277,7 +2306,9 @@ int uvc_ctrl_init_device(struct uvc_device *dev)
>  	struct uvc_entity *entity;
>  	unsigned int i;
>  
> -	INIT_WORK(&dev->async_ctrl.work, uvc_ctrl_status_event_work);
> +	INIT_WORK(&dev->async_ctrl_work, uvc_ctrl_status_event_work);
> +	mutex_init(&dev->async_ctrl_lock);
> +	INIT_LIST_HEAD(&dev->async_ctrl_list);
>  
>  	/* Walk the entities list and instantiate controls */
>  	list_for_each_entry(entity, &dev->entities, list) {
> @@ -2348,8 +2379,8 @@ void uvc_ctrl_cleanup_device(struct uvc_device *dev)
>  	unsigned int i;
>  
>  	/* Can be uninitialized if we are aborting on probe error. */
> -	if (dev->async_ctrl.work.func)
> -		cancel_work_sync(&dev->async_ctrl.work);
> +	if (dev->async_ctrl_work.func)
> +		cancel_work_sync(&dev->async_ctrl_work);
>  
>  	/* Free controls and control mappings for all entities. */
>  	list_for_each_entry(entity, &dev->entities, list) {
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 0db6c2e0bd98..afcaf49fad1a 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -637,6 +637,14 @@ struct uvc_device_info {
>  	u32	meta_format;
>  };
>  
> +struct uvc_ctrl_work {
> +	struct list_head list;
> +	struct urb *urb;
> +	struct uvc_video_chain *chain;
> +	struct uvc_control *ctrl;
> +	u8 data[UVC_MAX_STATUS_SIZE];
> +};
> +
>  struct uvc_device {
>  	struct usb_device *udev;
>  	struct usb_interface *intf;
> @@ -673,13 +681,10 @@ struct uvc_device {
>  	struct input_dev *input;
>  	char input_phys[64];
>  
> -	struct uvc_ctrl_work {
> -		struct work_struct work;
> -		struct urb *urb;
> -		struct uvc_video_chain *chain;
> -		struct uvc_control *ctrl;
> -		u8 data[UVC_MAX_STATUS_SIZE];
> -	} async_ctrl;
> +	/* Async control */
> +	struct work_struct async_ctrl_work;
> +	struct list_head async_ctrl_list;
> +	struct mutex async_ctrl_lock;
>  };
>  
>  enum uvc_handle_state {
diff mbox series

Patch

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index aa18dcdf8165..69b2fc6ce12c 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1275,11 +1275,9 @@  static void uvc_ctrl_send_slave_event(struct uvc_video_chain *chain,
 	uvc_ctrl_send_event(chain, handle, ctrl, mapping, val, changes);
 }
 
-static void uvc_ctrl_status_event_work(struct work_struct *work)
+static void __uvc_ctrl_status_event_work(struct uvc_device *dev,
+					 struct uvc_ctrl_work *w)
 {
-	struct uvc_device *dev = container_of(work, struct uvc_device,
-					      async_ctrl.work);
-	struct uvc_ctrl_work *w = &dev->async_ctrl;
 	struct uvc_video_chain *chain = w->chain;
 	struct uvc_control_mapping *mapping;
 	struct uvc_control *ctrl = w->ctrl;
@@ -1321,23 +1319,54 @@  static void uvc_ctrl_status_event_work(struct work_struct *work)
 			   ret);
 }
 
+static void uvc_ctrl_status_event_work(struct work_struct *work)
+{
+	struct uvc_device *dev = container_of(work, struct uvc_device,
+					      async_ctrl_work);
+	struct uvc_ctrl_work *w;
+
+	do {
+		mutex_lock(&dev->async_ctrl_lock);
+		w = list_first_entry_or_null(&dev->async_ctrl_list,
+					     struct uvc_ctrl_work,
+					     list);
+		if (w)
+			list_del(&w->list);
+		mutex_unlock(&dev->async_ctrl_lock);
+
+		if (!w)
+			return;
+
+		__uvc_ctrl_status_event_work(dev, w);
+		kfree(w);
+	} while (w);
+}
+
 bool uvc_ctrl_status_event(struct urb *urb, struct uvc_video_chain *chain,
 			   struct uvc_control *ctrl, const u8 *data)
 {
 	struct uvc_device *dev = chain->dev;
-	struct uvc_ctrl_work *w = &dev->async_ctrl;
+	struct uvc_ctrl_work *w;
 
 	if (list_empty(&ctrl->info.mappings)) {
 		ctrl->handle = NULL;
 		return false;
 	}
 
+	w = kzalloc(sizeof(*w), GFP_KERNEL);
+	if (WARN(!w, "Not enough memory to trigger uvc event"))
+		return false;
+
 	memcpy(w->data, data, ctrl->info.size);
 	w->urb = urb;
 	w->chain = chain;
 	w->ctrl = ctrl;
 
-	schedule_work(&w->work);
+	mutex_lock(&dev->async_ctrl_lock);
+	list_add_tail(&w->list, &dev->async_ctrl_list);
+	mutex_unlock(&dev->async_ctrl_lock);
+
+	schedule_work(&dev->async_ctrl_work);
 
 	return true;
 }
@@ -2277,7 +2306,9 @@  int uvc_ctrl_init_device(struct uvc_device *dev)
 	struct uvc_entity *entity;
 	unsigned int i;
 
-	INIT_WORK(&dev->async_ctrl.work, uvc_ctrl_status_event_work);
+	INIT_WORK(&dev->async_ctrl_work, uvc_ctrl_status_event_work);
+	mutex_init(&dev->async_ctrl_lock);
+	INIT_LIST_HEAD(&dev->async_ctrl_list);
 
 	/* Walk the entities list and instantiate controls */
 	list_for_each_entry(entity, &dev->entities, list) {
@@ -2348,8 +2379,8 @@  void uvc_ctrl_cleanup_device(struct uvc_device *dev)
 	unsigned int i;
 
 	/* Can be uninitialized if we are aborting on probe error. */
-	if (dev->async_ctrl.work.func)
-		cancel_work_sync(&dev->async_ctrl.work);
+	if (dev->async_ctrl_work.func)
+		cancel_work_sync(&dev->async_ctrl_work);
 
 	/* Free controls and control mappings for all entities. */
 	list_for_each_entry(entity, &dev->entities, list) {
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 0db6c2e0bd98..afcaf49fad1a 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -637,6 +637,14 @@  struct uvc_device_info {
 	u32	meta_format;
 };
 
+struct uvc_ctrl_work {
+	struct list_head list;
+	struct urb *urb;
+	struct uvc_video_chain *chain;
+	struct uvc_control *ctrl;
+	u8 data[UVC_MAX_STATUS_SIZE];
+};
+
 struct uvc_device {
 	struct usb_device *udev;
 	struct usb_interface *intf;
@@ -673,13 +681,10 @@  struct uvc_device {
 	struct input_dev *input;
 	char input_phys[64];
 
-	struct uvc_ctrl_work {
-		struct work_struct work;
-		struct urb *urb;
-		struct uvc_video_chain *chain;
-		struct uvc_control *ctrl;
-		u8 data[UVC_MAX_STATUS_SIZE];
-	} async_ctrl;
+	/* Async control */
+	struct work_struct async_ctrl_work;
+	struct list_head async_ctrl_list;
+	struct mutex async_ctrl_lock;
 };
 
 enum uvc_handle_state {