(has_op(master, op) ? master->ops->op(master) : 0)
/* Internal temporary helper struct, one for each v4l2_ext_control */
-struct ctrl_helper {
+struct v4l2_ctrl_helper {
+ /* Pointer to the control reference of the master control */
+ struct v4l2_ctrl_ref *mref;
/* The control corresponding to the v4l2_ext_control ID field. */
struct v4l2_ctrl *ctrl;
- /* Used internally to mark whether this control was already
- processed. */
- bool handled;
+ /* v4l2_ext_control index of the next control belonging to the
+ same cluster, or 0 if there isn't any. */
+ u32 next;
};
/* Small helper function to determine if the autocluster is set to manual
return 0;
}
-static int ctrl_to_user(struct v4l2_ext_control *c,
- struct v4l2_ctrl *ctrl)
-{
- if (ctrl->is_volatile)
- return new_to_user(c, ctrl);
- return cur_to_user(c, ctrl);
-}
-
-static int ctrl_is_volatile(struct v4l2_ext_control *c,
- struct v4l2_ctrl *ctrl)
-{
- return ctrl->is_volatile;
-}
-
/* Copy the new value to the current value. */
static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl,
bool update_inactive)
return diff;
}
-/* Validate a new control */
-static int validate_new(struct v4l2_ctrl *ctrl)
+/* Validate integer-type control */
+static int validate_new_int(const struct v4l2_ctrl *ctrl, s32 *pval)
{
- s32 val = ctrl->val;
- char *s = ctrl->string;
+ s32 val = *pval;
u32 offset;
- size_t len;
switch (ctrl->type) {
case V4L2_CTRL_TYPE_INTEGER:
offset = val - ctrl->minimum;
offset = ctrl->step * (offset / ctrl->step);
val = ctrl->minimum + offset;
- ctrl->val = val;
+ *pval = val;
return 0;
case V4L2_CTRL_TYPE_BOOLEAN:
- ctrl->val = !!ctrl->val;
+ *pval = !!val;
return 0;
case V4L2_CTRL_TYPE_MENU:
case V4L2_CTRL_TYPE_BUTTON:
case V4L2_CTRL_TYPE_CTRL_CLASS:
- ctrl->val64 = 0;
+ *pval = 0;
return 0;
+ default:
+ return -EINVAL;
+ }
+}
+
+/* Validate a new control */
+static int validate_new(const struct v4l2_ctrl *ctrl, struct v4l2_ext_control *c)
+{
+ char *s = c->string;
+ size_t len;
+
+ switch (ctrl->type) {
+ case V4L2_CTRL_TYPE_INTEGER:
+ case V4L2_CTRL_TYPE_BOOLEAN:
+ case V4L2_CTRL_TYPE_MENU:
+ case V4L2_CTRL_TYPE_BUTTON:
+ case V4L2_CTRL_TYPE_CTRL_CLASS:
+ return validate_new_int(ctrl, &c->value);
+
case V4L2_CTRL_TYPE_INTEGER64:
return 0;
Find the controls in the control array and do some basic checks. */
static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
struct v4l2_ext_controls *cs,
- struct ctrl_helper *helpers)
+ struct v4l2_ctrl_helper *helpers)
{
+ struct v4l2_ctrl_helper *h;
+ bool have_clusters = false;
u32 i;
- for (i = 0; i < cs->count; i++) {
+ for (i = 0, h = helpers; i < cs->count; i++, h++) {
struct v4l2_ext_control *c = &cs->controls[i];
+ struct v4l2_ctrl_ref *ref;
struct v4l2_ctrl *ctrl;
u32 id = c->id & V4L2_CTRL_ID_MASK;
extended controls */
if (id >= V4L2_CID_PRIVATE_BASE)
return -EINVAL;
- ctrl = v4l2_ctrl_find(hdl, id);
- if (ctrl == NULL)
+ ref = find_ref_lock(hdl, id);
+ if (ref == NULL)
return -EINVAL;
+ ctrl = ref->ctrl;
if (ctrl->flags & V4L2_CTRL_FLAG_DISABLED)
return -EINVAL;
- helpers[i].ctrl = ctrl;
- helpers[i].handled = false;
+ if (ctrl->cluster[0]->ncontrols > 1)
+ have_clusters = true;
+ if (ctrl->cluster[0] != ctrl)
+ ref = find_ref_lock(hdl, ctrl->cluster[0]->id);
+ /* Store the ref to the master control of the cluster */
+ h->mref = ref;
+ h->ctrl = ctrl;
+ /* Initially set next to 0, meaning that there is no other
+ control in this helper array belonging to the same
+ cluster */
+ h->next = 0;
}
- return 0;
-}
-typedef int (*cluster_func)(struct v4l2_ext_control *c,
- struct v4l2_ctrl *ctrl);
+ /* We are done if there were no controls that belong to a multi-
+ control cluster. */
+ if (!have_clusters)
+ return 0;
-/* Walk over all controls in v4l2_ext_controls belonging to the same cluster
- and call the provided function. */
-static int cluster_walk(unsigned from,
- struct v4l2_ext_controls *cs,
- struct ctrl_helper *helpers,
- cluster_func f)
-{
- struct v4l2_ctrl **cluster = helpers[from].ctrl->cluster;
- int ret = 0;
- int i;
+ /* The code below figures out in O(n) time which controls in the list
+ belong to the same cluster. */
- /* Find any controls from the same cluster and call the function */
- for (i = from; !ret && i < cs->count; i++) {
- struct v4l2_ctrl *ctrl = helpers[i].ctrl;
+ /* This has to be done with the handler lock taken. */
+ mutex_lock(&hdl->lock);
- if (!helpers[i].handled && ctrl->cluster == cluster)
- ret = f(&cs->controls[i], ctrl);
+ /* First zero the helper field in the master control references */
+ for (i = 0; i < cs->count; i++)
+ helpers[i].mref->helper = 0;
+ for (i = 0, h = helpers; i < cs->count; i++, h++) {
+ struct v4l2_ctrl_ref *mref = h->mref;
+
+ /* If the mref->helper is set, then it points to an earlier
+ helper that belongs to the same cluster. */
+ if (mref->helper) {
+ /* Set the next field of mref->helper to the current
+ index: this means that that earlier helper now
+ points to the next helper in the same cluster. */
+ mref->helper->next = i;
+ /* mref should be set only for the first helper in the
+ cluster, clear the others. */
+ h->mref = NULL;
+ }
+ /* Point the mref helper to the current helper struct. */
+ mref->helper = h;
}
- return ret;
-}
-
-static void cluster_done(unsigned from,
- struct v4l2_ext_controls *cs,
- struct ctrl_helper *helpers)
-{
- struct v4l2_ctrl **cluster = helpers[from].ctrl->cluster;
- int i;
-
- /* Find any controls from the same cluster and mark them as handled */
- for (i = from; i < cs->count; i++)
- if (helpers[i].ctrl->cluster == cluster)
- helpers[i].handled = true;
+ mutex_unlock(&hdl->lock);
+ return 0;
}
/* Handles the corner case where cs->count == 0. It checks whether the
/* Get extended controls. Allocates the helpers array if needed. */
int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs)
{
- struct ctrl_helper helper[4];
- struct ctrl_helper *helpers = helper;
+ struct v4l2_ctrl_helper helper[4];
+ struct v4l2_ctrl_helper *helpers = helper;
int ret;
int i, j;
ret = -EACCES;
for (i = 0; !ret && i < cs->count; i++) {
- struct v4l2_ctrl *ctrl = helpers[i].ctrl;
- struct v4l2_ctrl *master = ctrl->cluster[0];
- bool has_volatiles;
+ int (*ctrl_to_user)(struct v4l2_ext_control *c,
+ struct v4l2_ctrl *ctrl) = cur_to_user;
+ struct v4l2_ctrl *master;
- if (helpers[i].handled)
+ if (helpers[i].mref == NULL)
continue;
+ master = helpers[i].mref->ctrl;
cs->error_idx = i;
- /* Any volatile controls requested from this cluster? */
- has_volatiles = ctrl->is_volatile;
- if (!has_volatiles && has_op(master, g_volatile_ctrl) &&
- master->ncontrols > 1)
- has_volatiles = cluster_walk(i, cs, helpers,
- ctrl_is_volatile);
-
v4l2_ctrl_lock(master);
/* g_volatile_ctrl will update the new control values */
- if (has_volatiles && !is_cur_manual(master)) {
+ if (has_op(master, g_volatile_ctrl) && !is_cur_manual(master)) {
for (j = 0; j < master->ncontrols; j++)
cur_to_new(master->cluster[j]);
ret = call_op(master, g_volatile_ctrl);
+ ctrl_to_user = new_to_user;
}
/* If OK, then copy the current (for non-volatile controls)
or the new (for volatile controls) control values to the
caller */
- if (!ret)
- ret = cluster_walk(i, cs, helpers, ctrl_to_user);
+ if (!ret) {
+ u32 idx = i;
+
+ do {
+ ret = ctrl_to_user(cs->controls + idx,
+ helpers[idx].ctrl);
+ idx = helpers[idx].next;
+ } while (!ret && idx);
+ }
v4l2_ctrl_unlock(master);
- cluster_done(i, cs, helpers);
}
if (cs->count > ARRAY_SIZE(helper))
struct v4l2_ctrl *master, bool set)
{
bool update_flag;
- bool try = !set;
- int ret = 0;
+ int ret;
int i;
/* Go through the cluster and either validate the new value or
(if no new value was set), copy the current value to the new
value, ensuring a consistent view for the control ops when
called. */
- for (i = 0; !ret && i < master->ncontrols; i++) {
+ for (i = 0; i < master->ncontrols; i++) {
struct v4l2_ctrl *ctrl = master->cluster[i];
if (ctrl == NULL)
continue;
- if (ctrl->is_new) {
- /* Double check this: it may have changed since the
- last check in try_or_set_ext_ctrls(). */
- if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
- return -EBUSY;
-
- /* Validate if required */
- if (!set)
- ret = validate_new(ctrl);
+ if (!ctrl->is_new) {
+ cur_to_new(ctrl);
continue;
}
- /* No new value was set, so copy the current and force
- a call to try_ctrl later, since the values for the cluster
- may now have changed and the end result might be invalid. */
- try = true;
- cur_to_new(ctrl);
+ /* Check again: it may have changed since the
+ previous check in try_or_set_ext_ctrls(). */
+ if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
+ return -EBUSY;
}
- /* For larger clusters you have to call try_ctrl again to
- verify that the controls are still valid after the
- 'cur_to_new' above. */
- if (!ret && try)
- ret = call_op(master, try_ctrl);
+ ret = call_op(master, try_ctrl);
/* Don't set if there is no change */
if (ret || !set || !cluster_changed(master))
return ret;
ret = call_op(master, s_ctrl);
- /* If OK, then make the new values permanent. */
if (ret)
return ret;
+ /* If OK, then make the new values permanent. */
update_flag = is_cur_manual(master) != is_new_manual(master);
for (i = 0; i < master->ncontrols; i++)
new_to_cur(fh, master->cluster[i], update_flag && i > 0);
static int try_or_set_ext_ctrls(struct v4l2_fh *fh,
struct v4l2_ctrl_handler *hdl,
struct v4l2_ext_controls *cs,
- struct ctrl_helper *helpers,
+ struct v4l2_ctrl_helper *helpers,
bool set)
{
unsigned i, j;
int ret = 0;
+ /* Phase 1: validation */
+ cs->error_idx = cs->count;
for (i = 0; i < cs->count; i++) {
struct v4l2_ctrl *ctrl = helpers[i].ctrl;
- cs->error_idx = i;
+ if (!set)
+ cs->error_idx = i;
if (ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY)
return -EACCES;
best-effort to avoid that. */
if (set && (ctrl->flags & V4L2_CTRL_FLAG_GRABBED))
return -EBUSY;
+ ret = validate_new(ctrl, &cs->controls[i]);
+ if (ret)
+ return ret;
}
+ /* Phase 2: set/try controls */
for (i = 0; !ret && i < cs->count; i++) {
- struct v4l2_ctrl *ctrl = helpers[i].ctrl;
- struct v4l2_ctrl *master = ctrl->cluster[0];
+ struct v4l2_ctrl *master;
+ u32 idx = i;
- if (helpers[i].handled)
+ if (helpers[i].mref == NULL)
continue;
cs->error_idx = i;
- v4l2_ctrl_lock(ctrl);
+ master = helpers[i].mref->ctrl;
+ v4l2_ctrl_lock(master);
/* Reset the 'is_new' flags of the cluster */
for (j = 0; j < master->ncontrols; j++)
/* Copy the new caller-supplied control values.
user_to_new() sets 'is_new' to 1. */
- ret = cluster_walk(i, cs, helpers, user_to_new);
+ do {
+ ret = user_to_new(cs->controls + idx, helpers[idx].ctrl);
+ idx = helpers[idx].next;
+ } while (!ret && idx);
if (!ret)
ret = try_or_set_control_cluster(fh, master, set);
/* Copy the new values back to userspace. */
- if (!ret)
- ret = cluster_walk(i, cs, helpers, new_to_user);
-
- v4l2_ctrl_unlock(ctrl);
- cluster_done(i, cs, helpers);
+ if (!ret) {
+ idx = i;
+ do {
+ ret = user_to_new(cs->controls + idx,
+ helpers[idx].ctrl);
+ idx = helpers[idx].next;
+ } while (!ret && idx);
+ }
+ v4l2_ctrl_unlock(master);
}
return ret;
}
struct v4l2_ext_controls *cs,
bool set)
{
- struct ctrl_helper helper[4];
- struct ctrl_helper *helpers = helper;
+ struct v4l2_ctrl_helper helper[4];
+ struct v4l2_ctrl_helper *helpers = helper;
int ret;
- int i;
cs->error_idx = cs->count;
cs->ctrl_class = V4L2_CTRL_ID2CLASS(cs->ctrl_class);
return -ENOMEM;
}
ret = prepare_ext_ctrls(hdl, cs, helpers);
-
- /* First 'try' all controls and abort on error */
if (!ret)
- ret = try_or_set_ext_ctrls(NULL, hdl, cs, helpers, false);
- /* If this is a 'set' operation and the initial 'try' failed,
- then set error_idx to count to tell the application that no
- controls changed value yet. */
- if (set)
+ ret = try_or_set_ext_ctrls(fh, hdl, cs, helpers, set);
+ else if (set)
cs->error_idx = cs->count;
- if (!ret && set) {
- /* Reset 'handled' state */
- for (i = 0; i < cs->count; i++)
- helpers[i].handled = false;
- ret = try_or_set_ext_ctrls(fh, hdl, cs, helpers, true);
- }
if (cs->count > ARRAY_SIZE(helper))
kfree(helpers);
int ret;
int i;
+ ret = validate_new_int(ctrl, val);
+ if (ret)
+ return ret;
+
v4l2_ctrl_lock(ctrl);
/* Reset the 'is_new' flags of the cluster */
ctrl->val = *val;
ctrl->is_new = 1;
- ret = try_or_set_control_cluster(NULL, master, false);
- if (!ret)
- ret = try_or_set_control_cluster(fh, master, true);
+ ret = try_or_set_control_cluster(fh, master, true);
*val = ctrl->cur.val;
v4l2_ctrl_unlock(ctrl);
return ret;