Re: [PATCH v9] uvcvideo: send a control event when a Control Change interrupt arrives
Hi Laurent,
Thanks. Now we can get to the next one:
https://patchwork.linuxtv.org/patch/46184/ - without that one nobody can
get complete D4XX metadata. After I get your comments to it I'll address
them together with Sakari's ones.
Thanks
Guennadi
On Thu, 26 Jul 2018, Laurent Pinchart wrote:
> Hi Guennadi,
>
> Thank you for the patch.
>
> On Thursday, 26 July 2018 11:17:53 EEST Guennadi Liakhovetski wrote:
> > From: Guennadi Liakhovetski
> >
> > UVC defines a method of handling asynchronous controls, which sends a
> > USB packet over the interrupt pipe. This patch implements support for
> > such packets by sending a control event to the user. Since this can
> > involve USB traffic and, therefore, scheduling, this has to be done
> > in a work queue.
> >
> > Signed-off-by: Guennadi Liakhovetski
>
> Reviewed-by: Laurent Pinchart
>
> applied to my tree and pushed to the uvc/next branch.
>
> > ---
> >
> > v9:
> > - multiple optimisations and style improvements from Laurent - thanks
> > - avoid the handle rewriting race at least in cases, when the user only
> > sends a new control after receiving an event for the previous one
> >
> > Laurent, you added a couple of comments, using DocBook markup like
> > "@param" but you didn't mark those comments for DocBook processing with
> > "/**" - I don't care that much, just wanted to check, that that was
> > intentional.
>
> Yes, it's not worth compiling that as kerneldoc, I just wanted to mark
> references to variable names for clarity.
>
> > drivers/media/usb/uvc/uvc_ctrl.c | 211
> > - drivers/media/usb/uvc/uvc_status.c |
> > 121 ++---
> > drivers/media/usb/uvc/uvc_v4l2.c | 4 +-
> > drivers/media/usb/uvc/uvcvideo.h | 15 ++-
> > include/uapi/linux/uvcvideo.h | 2 +
> > 5 files changed, 286 insertions(+), 67 deletions(-)
> >
> > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c
> > b/drivers/media/usb/uvc/uvc_ctrl.c index 2a213c8..ddd069b 100644
> > --- a/drivers/media/usb/uvc/uvc_ctrl.c
> > +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> > @@ -20,6 +20,7 @@
> > #include
> > #include
> > #include
> > +#include
> > #include
> > #include
> >
> > @@ -971,12 +972,30 @@ static int uvc_ctrl_populate_cache(struct
> > uvc_video_chain *chain, return 0;
> > }
> >
> > +static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
> > + const u8 *data)
> > +{
> > + s32 value = mapping->get(mapping, UVC_GET_CUR, data);
> > +
> > + if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
> > + struct uvc_menu_info *menu = mapping->menu_info;
> > + unsigned int i;
> > +
> > + for (i = 0; i < mapping->menu_count; ++i, ++menu) {
> > + if (menu->value == value) {
> > + value = i;
> > + break;
> > + }
> > + }
> > + }
> > +
> > + return value;
> > +}
> > +
> > static int __uvc_ctrl_get(struct uvc_video_chain *chain,
> > struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
> > s32 *value)
> > {
> > - struct uvc_menu_info *menu;
> > - unsigned int i;
> > int ret;
> >
> > if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
> > @@ -993,18 +1012,8 @@ static int __uvc_ctrl_get(struct uvc_video_chain
> > *chain, ctrl->loaded = 1;
> > }
> >
> > - *value = mapping->get(mapping, UVC_GET_CUR,
> > - uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
> > -
> > - if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
> > - menu = mapping->menu_info;
> > - for (i = 0; i < mapping->menu_count; ++i, ++menu) {
> > - if (menu->value == *value) {
> > - *value = i;
> > - break;
> > - }
> > - }
> > - }
> > + *value = __uvc_ctrl_get_value(mapping,
> > + uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
> >
> > return 0;
> > }
> > @@ -1216,53 +1225,135 @@ static void uvc_ctrl_fill_event(struct
> > uvc_video_chain *chain, ev->u.ctrl.default_value = v4l2_ctrl.default_value;
> > }
> >
> > -static void uvc_ctrl_send_event(struct uvc_fh *handle,
> > - struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
> > - s32 value, u32 changes)
> > +/*
> > + * Send control change events to all subscribers for the @ctrl control. By
> > + * default the subscriber that generated the event, as identified by
> > @handle, + * is not notified unless it has set the
> > V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK flag. + * @handle can be NULL for
> > asynchronous events related to auto-update controls, + * in which case all
> > subscribers are notified.
> > + */
> > +static void uvc_ctrl_send_event(struct uvc_video_chain *chain,
> > + struct uvc_fh *handle, struct uvc_control *ctrl,
> > + struct uvc_control_mapping *mapping, s32 value, u32 changes)
> > {
> > + struct v4l2_fh *originator =
Re: [PATCH v9] uvcvideo: send a control event when a Control Change interrupt arrives
Hi Guennadi,
Thank you for the patch.
On Thursday, 26 July 2018 11:17:53 EEST Guennadi Liakhovetski wrote:
> From: Guennadi Liakhovetski
>
> UVC defines a method of handling asynchronous controls, which sends a
> USB packet over the interrupt pipe. This patch implements support for
> such packets by sending a control event to the user. Since this can
> involve USB traffic and, therefore, scheduling, this has to be done
> in a work queue.
>
> Signed-off-by: Guennadi Liakhovetski
Reviewed-by: Laurent Pinchart
applied to my tree and pushed to the uvc/next branch.
> ---
>
> v9:
> - multiple optimisations and style improvements from Laurent - thanks
> - avoid the handle rewriting race at least in cases, when the user only
> sends a new control after receiving an event for the previous one
>
> Laurent, you added a couple of comments, using DocBook markup like
> "@param" but you didn't mark those comments for DocBook processing with
> "/**" - I don't care that much, just wanted to check, that that was
> intentional.
Yes, it's not worth compiling that as kerneldoc, I just wanted to mark
references to variable names for clarity.
> drivers/media/usb/uvc/uvc_ctrl.c | 211
> - drivers/media/usb/uvc/uvc_status.c |
> 121 ++---
> drivers/media/usb/uvc/uvc_v4l2.c | 4 +-
> drivers/media/usb/uvc/uvcvideo.h | 15 ++-
> include/uapi/linux/uvcvideo.h | 2 +
> 5 files changed, 286 insertions(+), 67 deletions(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c
> b/drivers/media/usb/uvc/uvc_ctrl.c index 2a213c8..ddd069b 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -20,6 +20,7 @@
> #include
> #include
> #include
> +#include
> #include
> #include
>
> @@ -971,12 +972,30 @@ static int uvc_ctrl_populate_cache(struct
> uvc_video_chain *chain, return 0;
> }
>
> +static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
> + const u8 *data)
> +{
> + s32 value = mapping->get(mapping, UVC_GET_CUR, data);
> +
> + if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
> + struct uvc_menu_info *menu = mapping->menu_info;
> + unsigned int i;
> +
> + for (i = 0; i < mapping->menu_count; ++i, ++menu) {
> + if (menu->value == value) {
> + value = i;
> + break;
> + }
> + }
> + }
> +
> + return value;
> +}
> +
> static int __uvc_ctrl_get(struct uvc_video_chain *chain,
> struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
> s32 *value)
> {
> - struct uvc_menu_info *menu;
> - unsigned int i;
> int ret;
>
> if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
> @@ -993,18 +1012,8 @@ static int __uvc_ctrl_get(struct uvc_video_chain
> *chain, ctrl->loaded = 1;
> }
>
> - *value = mapping->get(mapping, UVC_GET_CUR,
> - uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
> -
> - if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
> - menu = mapping->menu_info;
> - for (i = 0; i < mapping->menu_count; ++i, ++menu) {
> - if (menu->value == *value) {
> - *value = i;
> - break;
> - }
> - }
> - }
> + *value = __uvc_ctrl_get_value(mapping,
> + uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
>
> return 0;
> }
> @@ -1216,53 +1225,135 @@ static void uvc_ctrl_fill_event(struct
> uvc_video_chain *chain, ev->u.ctrl.default_value = v4l2_ctrl.default_value;
> }
>
> -static void uvc_ctrl_send_event(struct uvc_fh *handle,
> - struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
> - s32 value, u32 changes)
> +/*
> + * Send control change events to all subscribers for the @ctrl control. By
> + * default the subscriber that generated the event, as identified by
> @handle, + * is not notified unless it has set the
> V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK flag. + * @handle can be NULL for
> asynchronous events related to auto-update controls, + * in which case all
> subscribers are notified.
> + */
> +static void uvc_ctrl_send_event(struct uvc_video_chain *chain,
> + struct uvc_fh *handle, struct uvc_control *ctrl,
> + struct uvc_control_mapping *mapping, s32 value, u32 changes)
> {
> + struct v4l2_fh *originator = handle ? &handle->vfh : NULL;
> struct v4l2_subscribed_event *sev;
> struct v4l2_event ev;
>
> if (list_empty(&mapping->ev_subs))
> return;
>
> - uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, value, changes);
> + uvc_ctrl_fill_event(chain, &ev, ctrl, mapping, value, changes);
>
> list_for_each_entry(sev, &mapping->ev_subs, node) {
> - if (sev->fh != &handle->vfh ||
> + if (sev->fh != originat
[PATCH v9] uvcvideo: send a control event when a Control Change interrupt arrives
From: Guennadi Liakhovetski
UVC defines a method of handling asynchronous controls, which sends a
USB packet over the interrupt pipe. This patch implements support for
such packets by sending a control event to the user. Since this can
involve USB traffic and, therefore, scheduling, this has to be done
in a work queue.
Signed-off-by: Guennadi Liakhovetski
---
v9:
- multiple optimisations and style improvements from Laurent - thanks
- avoid the handle rewriting race at least in cases, when the user only
sends a new control after receiving an event for the previous one
Laurent, you added a couple of comments, using DocBook markup like
"@param" but you didn't mark those comments for DocBook processing with
"/**" - I don't care that much, just wanted to check, that that was
intentional.
drivers/media/usb/uvc/uvc_ctrl.c | 211 -
drivers/media/usb/uvc/uvc_status.c | 121 ++---
drivers/media/usb/uvc/uvc_v4l2.c | 4 +-
drivers/media/usb/uvc/uvcvideo.h | 15 ++-
include/uapi/linux/uvcvideo.h | 2 +
5 files changed, 286 insertions(+), 67 deletions(-)
diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 2a213c8..ddd069b 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -20,6 +20,7 @@
#include
#include
#include
+#include
#include
#include
@@ -971,12 +972,30 @@ static int uvc_ctrl_populate_cache(struct uvc_video_chain
*chain,
return 0;
}
+static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
+ const u8 *data)
+{
+ s32 value = mapping->get(mapping, UVC_GET_CUR, data);
+
+ if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
+ struct uvc_menu_info *menu = mapping->menu_info;
+ unsigned int i;
+
+ for (i = 0; i < mapping->menu_count; ++i, ++menu) {
+ if (menu->value == value) {
+ value = i;
+ break;
+ }
+ }
+ }
+
+ return value;
+}
+
static int __uvc_ctrl_get(struct uvc_video_chain *chain,
struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
s32 *value)
{
- struct uvc_menu_info *menu;
- unsigned int i;
int ret;
if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
@@ -993,18 +1012,8 @@ static int __uvc_ctrl_get(struct uvc_video_chain *chain,
ctrl->loaded = 1;
}
- *value = mapping->get(mapping, UVC_GET_CUR,
- uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
-
- if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
- menu = mapping->menu_info;
- for (i = 0; i < mapping->menu_count; ++i, ++menu) {
- if (menu->value == *value) {
- *value = i;
- break;
- }
- }
- }
+ *value = __uvc_ctrl_get_value(mapping,
+ uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
return 0;
}
@@ -1216,53 +1225,135 @@ static void uvc_ctrl_fill_event(struct uvc_video_chain
*chain,
ev->u.ctrl.default_value = v4l2_ctrl.default_value;
}
-static void uvc_ctrl_send_event(struct uvc_fh *handle,
- struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
- s32 value, u32 changes)
+/*
+ * Send control change events to all subscribers for the @ctrl control. By
+ * default the subscriber that generated the event, as identified by @handle,
+ * is not notified unless it has set the V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK flag.
+ * @handle can be NULL for asynchronous events related to auto-update controls,
+ * in which case all subscribers are notified.
+ */
+static void uvc_ctrl_send_event(struct uvc_video_chain *chain,
+ struct uvc_fh *handle, struct uvc_control *ctrl,
+ struct uvc_control_mapping *mapping, s32 value, u32 changes)
{
+ struct v4l2_fh *originator = handle ? &handle->vfh : NULL;
struct v4l2_subscribed_event *sev;
struct v4l2_event ev;
if (list_empty(&mapping->ev_subs))
return;
- uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, value, changes);
+ uvc_ctrl_fill_event(chain, &ev, ctrl, mapping, value, changes);
list_for_each_entry(sev, &mapping->ev_subs, node) {
- if (sev->fh != &handle->vfh ||
+ if (sev->fh != originator ||
(sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK) ||
(changes & V4L2_EVENT_CTRL_CH_FLAGS))
v4l2_event_queue_fh(sev->fh, &ev);
}
}
-static void uvc_ctrl_send_slave_event(struct uvc_fh *handle,
- struct uvc_control *master, u32 slave_id,
- const struct v4l2_ext_control *xctrls, unsigned int xctrls_count)
+/*
+ * Send control chan
