XU controls initialization requires querying the device for control
information. As some buggy UVC devices will crash when queried
repeatedly in a tight loop, delay XU controls initialization until first
use.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/video/uvc/uvc_ctrl.c | 194 ++++++++++++++++++++----------------
1 files changed, 107 insertions(+), 87 deletions(-)
diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c
index 97a2395..a0c9d58 100644
--- a/drivers/media/video/uvc/uvc_ctrl.c
+++ b/drivers/media/video/uvc/uvc_ctrl.c
@@ -1164,6 +1164,90 @@ int uvc_ctrl_set(struct uvc_video_chain *chain,
* Dynamic controls
*/
+/*
+ * Query control information (size and flags) for XU controls.
+ */
+static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
+ const struct uvc_control *ctrl, struct uvc_control_info *info)
+{
+ u8 *data;
+ int ret;
+
+ data = kmalloc(2, GFP_KERNEL);
+ if (data == NULL)
+ return -ENOMEM;
+
+ memcpy(info->entity, ctrl->entity->extension.guidExtensionCode,
+ sizeof(info->entity));
+ info->index = ctrl->index;
+ info->selector = ctrl->index + 1;
+
+ /* Query and verify the control length (GET_LEN) */
+ ret = uvc_query_ctrl(dev, UVC_GET_LEN, ctrl->entity->id, dev->intfnum,
+ info->selector, data, 2);
+ if (ret < 0) {
+ uvc_trace(UVC_TRACE_CONTROL,
+ "GET_LEN failed on control %pUl/%u (%d).\n",
+ info->entity, info->selector, ret);
+ goto done;
+ }
+
+ info->size = le16_to_cpup((__le16 *)data);
+
+ /* Query the control information (GET_INFO) */
+ ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id, dev->intfnum,
+ info->selector, data, 1);
+ if (ret < 0) {
+ uvc_trace(UVC_TRACE_CONTROL,
+ "GET_INFO failed on control %pUl/%u (%d).\n",
+ info->entity, info->selector, ret);
+ goto done;
+ }
+
+ info->flags = UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX
+ | UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF
+ | (data[0] & UVC_CONTROL_CAP_GET ? UVC_CONTROL_GET_CUR : 0)
+ | (data[0] & UVC_CONTROL_CAP_SET ? UVC_CONTROL_SET_CUR : 0)
+ | (data[0] & UVC_CONTROL_CAP_AUTOUPDATE ?
+ UVC_CONTROL_AUTO_UPDATE : 0);
+
+ uvc_trace(UVC_TRACE_CONTROL, "XU control %pUl/%u queried: len %u, "
+ "flags { get %u set %u auto %u }.\n",
+ info->entity, info->selector, info->size,
+ (info->flags & UVC_CONTROL_GET_CUR) ? 1 : 0,
+ (info->flags & UVC_CONTROL_SET_CUR) ? 1 : 0,
+ (info->flags & UVC_CONTROL_AUTO_UPDATE) ? 1 : 0);
+
+done:
+ kfree(data);
+ return ret;
+}
+
+static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
+ const struct uvc_control_info *info);
+
+static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
+ struct uvc_control *ctrl)
+{
+ struct uvc_control_info info;
+ int ret;
+
+ if (ctrl->initialized)
+ return 0;
+
+ ret = uvc_ctrl_fill_xu_info(dev, ctrl, &info);
+ if (ret < 0)
+ return ret;
+
+ ret = uvc_ctrl_add_info(dev, ctrl, &info);
+ if (ret < 0)
+ uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize control "
+ "%pUl/%u on device %s entity %u\n", info.entity,
+ info.selector, dev->udev->devpath, ctrl->entity->id);
+
+ return ret;
+}
+
int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
struct uvc_xu_control *xctrl, int set)
{
@@ -1186,13 +1270,10 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
return -EINVAL;
}
- /* Find the control. */
+ /* Find the control and perform delayed initialization if needed. */
for (i = 0; i < entity->ncontrols; ++i) {
ctrl = &entity->controls[i];
- if (!ctrl->initialized)
- continue;
-
- if (ctrl->info.selector == xctrl->selector) {
+ if (ctrl->index == xctrl->selector - 1) {
found = 1;
break;
}
@@ -1204,6 +1285,10 @@ int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
return -EINVAL;
}
+ ret = uvc_ctrl_init_xu_ctrl(chain->dev, ctrl);
+ if (ret < 0)
+ return -ENOENT;
+
/* Validate control data size. */
if (ctrl->info.size != xctrl->size)
return -EINVAL;
@@ -1295,65 +1380,6 @@ int uvc_ctrl_resume_device(struct uvc_device *dev)
*/
/*
- * Query control information (size and flags) for XU controls.
- */
-static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
- const struct uvc_control *ctrl, struct uvc_control_info *info)
-{
- u8 *data;
- int ret;
-
- data = kmalloc(2, GFP_KERNEL);
- if (data == NULL)
- return -ENOMEM;
-
- memcpy(info->entity, ctrl->entity->extension.guidExtensionCode,
- sizeof(info->entity));
- info->index = ctrl->index;
- info->selector = ctrl->index + 1;
-
- /* Query and verify the control length (GET_LEN) */
- ret = uvc_query_ctrl(dev, UVC_GET_LEN, ctrl->entity->id, dev->intfnum,
- info->selector, data, 2);
- if (ret < 0) {
- uvc_trace(UVC_TRACE_CONTROL,
- "GET_LEN failed on control %pUl/%u (%d).\n",
- info->entity, info->selector, ret);
- goto done;
- }
-
- info->size = le16_to_cpup((__le16 *)data);
-
- /* Query the control information (GET_INFO) */
- ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id, dev->intfnum,
- info->selector, data, 1);
- if (ret < 0) {
- uvc_trace(UVC_TRACE_CONTROL,
- "GET_INFO failed on control %pUl/%u (%d).\n",
- info->entity, info->selector, ret);
- goto done;
- }
-
- info->flags = UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX
- | UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF
- | (data[0] & UVC_CONTROL_CAP_GET ? UVC_CONTROL_GET_CUR : 0)
- | (data[0] & UVC_CONTROL_CAP_SET ? UVC_CONTROL_SET_CUR : 0)
- | (data[0] & UVC_CONTROL_CAP_AUTOUPDATE ?
- UVC_CONTROL_AUTO_UPDATE : 0);
-
- uvc_trace(UVC_TRACE_CONTROL, "XU control %pUl/%u queried: len %u, "
- "flags { get %u set %u auto %u }.\n",
- info->entity, info->selector, info->size,
- (info->flags & UVC_CONTROL_GET_CUR) ? 1 : 0,
- (info->flags & UVC_CONTROL_SET_CUR) ? 1 : 0,
- (info->flags & UVC_CONTROL_AUTO_UPDATE) ? 1 : 0);
-
-done:
- kfree(data);
- return ret;
-}
-
-/*
* Add control information to a given control.
*/
static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
@@ -1434,7 +1460,7 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
if (mapping->id & ~V4L2_CTRL_ID_MASK) {
uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', control "
- "control id 0x%08x is invalid.\n", mapping->name,
+ "id 0x%08x is invalid.\n", mapping->name,
mapping->id);
return -EINVAL;
}
@@ -1443,13 +1469,13 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
list_for_each_entry(entity, &dev->entities, list) {
unsigned int i;
- if (!uvc_entity_match_guid(entity, mapping->entity))
+ if (UVC_ENTITY_TYPE(entity) != UVC_VC_EXTENSION_UNIT ||
+ !uvc_entity_match_guid(entity, mapping->entity))
continue;
for (i = 0; i < entity->ncontrols; ++i) {
ctrl = &entity->controls[i];
- if (ctrl->initialized &&
- ctrl->info.selector == mapping->selector) {
+ if (ctrl->index == mapping->selector - 1) {
found = 1;
break;
}
@@ -1464,6 +1490,13 @@ int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
if (mutex_lock_interruptible(&chain->ctrl_mutex))
return -ERESTARTSYS;
+ /* Perform delayed initialization of XU controls */
+ ret = uvc_ctrl_init_xu_ctrl(dev, ctrl);
+ if (ret < 0) {
+ ret = -ENOENT;
+ goto done;
+ }
+
list_for_each_entry(map, &ctrl->info.mappings, list) {
if (mapping->id == map->id) {
uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', "
@@ -1567,26 +1600,13 @@ static void uvc_ctrl_init_ctrl(struct uvc_device *dev, struct uvc_control *ctrl)
const struct uvc_control_mapping *mend =
mapping + ARRAY_SIZE(uvc_ctrl_mappings);
- /* Query XU controls for control information */
- if (UVC_ENTITY_TYPE(ctrl->entity) == UVC_VC_EXTENSION_UNIT) {
- struct uvc_control_info info;
- int ret;
-
- ret = uvc_ctrl_fill_xu_info(dev, ctrl, &info);
- if (ret < 0)
- return;
-
- ret = uvc_ctrl_add_info(dev, ctrl, &info);
- if (ret < 0) {
- /* Skip the control */
- uvc_trace(UVC_TRACE_CONTROL, "Failed to initialize "
- "control %pUl/%u on device %s entity %u\n",
- info.entity, info.selector, dev->udev->devpath,
- ctrl->entity->id);
- memset(ctrl, 0, sizeof(*ctrl));
- }
+ /* XU controls initialization requires querying the device for control
+ * information. As some buggy UVC devices will crash when queried
+ * repeatedly in a tight loop, delay XU controls initialization until
+ * first use.
+ */
+ if (UVC_ENTITY_TYPE(ctrl->entity) == UVC_VC_EXTENSION_UNIT)
return;
- }
for (; info < iend; ++info) {
if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
--
1.7.2.2
--
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