This patch adds a helper function that allows to modify range, i.e. minimum, maximum, step and default value of a v4l2 control, after the control has been created and initialized. This is helpful in situations when range of a control depends on user configurable parameters, e.g. camera sensor absolute exposure time depending on an output image resolution and frame rate. v4l2_ctrl_modify_range() function allows to modify range of an INTEGER, BOOL, MENU, INTEGER_MENU and BITMASK type controls. Based on a patch from Hans Verkuil http://patchwork.linuxtv.org/patch/8654. Signed-off-by: Sylwester Nawrocki <sylvester.nawrocki@xxxxxxxxx> Acked-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> --- Changes since previous version: - added missing V4L2_CTRL_TYPE_INTEGER_MENU in the switch statement in v4l2_ctrl_modify_range() function, - added DocBook entries in v4l2.xml, compat.xml --- Documentation/DocBook/media/v4l/compat.xml | 4 + Documentation/DocBook/media/v4l/v4l2.xml | 4 +- Documentation/DocBook/media/v4l/vidioc-dqevent.xml | 6 + drivers/media/v4l2-core/v4l2-ctrls.c | 143 ++++++++++++++------ include/media/v4l2-ctrls.h | 20 +++ include/uapi/linux/videodev2.h | 1 + 6 files changed, 138 insertions(+), 40 deletions(-) diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml index ebd2bfd..104a1a2 100644 --- a/Documentation/DocBook/media/v4l/compat.xml +++ b/Documentation/DocBook/media/v4l/compat.xml @@ -2486,6 +2486,10 @@ that used it. It was originally scheduled for removal in 2.6.35. <structname>v4l2_buffer</structname>. See <xref linkend="buffer-flags" />.</para> </listitem> + <listitem> + <para>Added <constant>V4L2_EVENT_CTRL_CH_RANGE</constant> control event + changes flag. See <xref linkend="changes-flags"/>.</para> + </listitem> </orderedlist> </section> diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml index 8fe2942..c3851a2 100644 --- a/Documentation/DocBook/media/v4l/v4l2.xml +++ b/Documentation/DocBook/media/v4l/v4l2.xml @@ -142,10 +142,12 @@ applications. --> <revision> <revnumber>3.9</revnumber> <date>2012-12-03</date> - <authorinitials>sa</authorinitials> + <authorinitials>sa, sn</authorinitials> <revremark>Added timestamp types to <structname>v4l2_buffer</structname>, see <xref linkend="buffer-flags" />. + Added <constant>V4L2_EVENT_CTRL_CH_RANGE</constant> control + event changes flag, see <xref linkend="changes-flags"/>. </revremark> </revision> diff --git a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml index 98a856f..89891ad 100644 --- a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml +++ b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml @@ -261,6 +261,12 @@ <entry>This control event was triggered because the control flags changed.</entry> </row> + <row> + <entry><constant>V4L2_EVENT_CTRL_CH_RANGE</constant></entry> + <entry>0x0004</entry> + <entry>This control event was triggered because the minimum, + maximum, step or the default value of the control changed.</entry> + </row> </tbody> </tgroup> </table> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index 7b486ac..3f27571 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -1158,8 +1158,7 @@ static int new_to_user(struct v4l2_ext_control *c, } /* Copy the new value to the current value. */ -static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, - bool update_inactive) +static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, u32 ch_flags) { bool changed = false; @@ -1183,8 +1182,8 @@ static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, ctrl->cur.val = ctrl->val; break; } - if (update_inactive) { - /* Note: update_inactive can only be true for auto clusters. */ + if (ch_flags & V4L2_EVENT_CTRL_CH_FLAGS) { + /* Note: CH_FLAGS is only set for auto clusters. */ ctrl->flags &= ~(V4L2_CTRL_FLAG_INACTIVE | V4L2_CTRL_FLAG_VOLATILE); if (!is_cur_manual(ctrl->cluster[0])) { @@ -1194,14 +1193,13 @@ static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, } fh = NULL; } - if (changed || update_inactive) { + if (changed || ch_flags) { /* If a control was changed that was not one of the controls modified by the application, then send the event to all. */ if (!ctrl->is_new) fh = NULL; send_event(fh, ctrl, - (changed ? V4L2_EVENT_CTRL_CH_VALUE : 0) | - (update_inactive ? V4L2_EVENT_CTRL_CH_FLAGS : 0)); + (changed ? V4L2_EVENT_CTRL_CH_VALUE : 0) | ch_flags); if (ctrl->call_notify && changed && ctrl->handler->notify) ctrl->handler->notify(ctrl, ctrl->handler->notify_priv); } @@ -1257,6 +1255,41 @@ static int cluster_changed(struct v4l2_ctrl *master) return diff; } +/* Control range checking */ +static int check_range(enum v4l2_ctrl_type type, + s32 min, s32 max, u32 step, s32 def) +{ + switch (type) { + case V4L2_CTRL_TYPE_BOOLEAN: + if (step != 1 || max > 1 || min < 0) + return -ERANGE; + /* fall through */ + case V4L2_CTRL_TYPE_INTEGER: + if (step <= 0 || min > max || def < min || def > max) + return -ERANGE; + return 0; + case V4L2_CTRL_TYPE_BITMASK: + if (step || min || !max || (def & ~max)) + return -ERANGE; + return 0; + case V4L2_CTRL_TYPE_MENU: + case V4L2_CTRL_TYPE_INTEGER_MENU: + if (min > max || def < min || def > max) + return -ERANGE; + /* Note: step == menu_skip_mask for menu controls. + So here we check if the default value is masked out. */ + if (step && ((1 << def) & step)) + return -EINVAL; + return 0; + case V4L2_CTRL_TYPE_STRING: + if (min > max || min < 0 || step < 1 || def) + return -ERANGE; + return 0; + default: + return 0; + } +} + /* Validate a new control */ static int validate_new(const struct v4l2_ctrl *ctrl, struct v4l2_ext_control *c) @@ -1529,30 +1562,21 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl, { struct v4l2_ctrl *ctrl; unsigned sz_extra = 0; + int err; if (hdl->error) return NULL; /* Sanity checks */ if (id == 0 || name == NULL || id >= V4L2_CID_PRIVATE_BASE || - (type == V4L2_CTRL_TYPE_INTEGER && step == 0) || - (type == V4L2_CTRL_TYPE_BITMASK && max == 0) || (type == V4L2_CTRL_TYPE_MENU && qmenu == NULL) || - (type == V4L2_CTRL_TYPE_INTEGER_MENU && qmenu_int == NULL) || - (type == V4L2_CTRL_TYPE_STRING && max == 0)) { - handler_set_err(hdl, -ERANGE); - return NULL; - } - if (type != V4L2_CTRL_TYPE_BITMASK && max < min) { + (type == V4L2_CTRL_TYPE_INTEGER_MENU && qmenu_int == NULL)) { handler_set_err(hdl, -ERANGE); return NULL; } - if ((type == V4L2_CTRL_TYPE_INTEGER || - type == V4L2_CTRL_TYPE_MENU || - type == V4L2_CTRL_TYPE_INTEGER_MENU || - type == V4L2_CTRL_TYPE_BOOLEAN) && - (def < min || def > max)) { - handler_set_err(hdl, -ERANGE); + err = check_range(type, min, max, step, def); + if (err) { + handler_set_err(hdl, err); return NULL; } if (type == V4L2_CTRL_TYPE_BITMASK && ((def & ~max) || min || step)) { @@ -2426,8 +2450,8 @@ EXPORT_SYMBOL(v4l2_ctrl_g_ctrl_int64); /* Core function that calls try/s_ctrl and ensures that the new value is copied to the current value on a set. Must be called with ctrl->handler->lock held. */ -static int try_or_set_cluster(struct v4l2_fh *fh, - struct v4l2_ctrl *master, bool set) +static int try_or_set_cluster(struct v4l2_fh *fh, struct v4l2_ctrl *master, + bool set, u32 ch_flags) { bool update_flag; int ret; @@ -2465,7 +2489,8 @@ static int try_or_set_cluster(struct v4l2_fh *fh, /* 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); + new_to_cur(fh, master->cluster[i], ch_flags | + ((update_flag && i > 0) ? V4L2_EVENT_CTRL_CH_FLAGS : 0)); return 0; } @@ -2592,7 +2617,7 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, } while (!ret && idx); if (!ret) - ret = try_or_set_cluster(fh, master, set); + ret = try_or_set_cluster(fh, master, set, 0); /* Copy the new values back to userspace. */ if (!ret) { @@ -2638,10 +2663,9 @@ EXPORT_SYMBOL(v4l2_subdev_s_ext_ctrls); /* Helper function for VIDIOC_S_CTRL compatibility */ static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, - struct v4l2_ext_control *c) + struct v4l2_ext_control *c, u32 ch_flags) { struct v4l2_ctrl *master = ctrl->cluster[0]; - int ret; int i; /* String controls are not supported. The user_to_new() and @@ -2651,12 +2675,6 @@ static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, if (ctrl->type == V4L2_CTRL_TYPE_STRING) return -EINVAL; - ret = validate_new(ctrl, c); - if (ret) - return ret; - - v4l2_ctrl_lock(ctrl); - /* Reset the 'is_new' flags of the cluster */ for (i = 0; i < master->ncontrols; i++) if (master->cluster[i]) @@ -2670,10 +2688,22 @@ static int set_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, update_from_auto_cluster(master); user_to_new(c, ctrl); - ret = try_or_set_cluster(fh, master, true); - cur_to_user(c, ctrl); + return try_or_set_cluster(fh, master, true, ch_flags); +} - v4l2_ctrl_unlock(ctrl); +/* Helper function for VIDIOC_S_CTRL compatibility */ +static int set_ctrl_lock(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, + struct v4l2_ext_control *c) +{ + int ret = validate_new(ctrl, c); + + if (!ret) { + v4l2_ctrl_lock(ctrl); + ret = set_ctrl(fh, ctrl, c, 0); + if (!ret) + cur_to_user(c, ctrl); + v4l2_ctrl_unlock(ctrl); + } return ret; } @@ -2691,7 +2721,7 @@ int v4l2_s_ctrl(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, return -EACCES; c.value = control->value; - ret = set_ctrl(fh, ctrl, &c); + ret = set_ctrl_lock(fh, ctrl, &c); control->value = c.value; return ret; } @@ -2710,7 +2740,7 @@ int v4l2_ctrl_s_ctrl(struct v4l2_ctrl *ctrl, s32 val) /* It's a driver bug if this happens. */ WARN_ON(!type_is_int(ctrl)); c.value = val; - return set_ctrl(NULL, ctrl, &c); + return set_ctrl_lock(NULL, ctrl, &c); } EXPORT_SYMBOL(v4l2_ctrl_s_ctrl); @@ -2721,7 +2751,7 @@ int v4l2_ctrl_s_ctrl_int64(struct v4l2_ctrl *ctrl, s64 val) /* It's a driver bug if this happens. */ WARN_ON(ctrl->type != V4L2_CTRL_TYPE_INTEGER64); c.value64 = val; - return set_ctrl(NULL, ctrl, &c); + return set_ctrl_lock(NULL, ctrl, &c); } EXPORT_SYMBOL(v4l2_ctrl_s_ctrl_int64); @@ -2741,6 +2771,41 @@ void v4l2_ctrl_notify(struct v4l2_ctrl *ctrl, v4l2_ctrl_notify_fnc notify, void } EXPORT_SYMBOL(v4l2_ctrl_notify); +int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, + s32 min, s32 max, u32 step, s32 def) +{ + int ret = check_range(ctrl->type, min, max, step, def); + struct v4l2_ext_control c; + + switch (ctrl->type) { + case V4L2_CTRL_TYPE_INTEGER: + case V4L2_CTRL_TYPE_BOOLEAN: + case V4L2_CTRL_TYPE_MENU: + case V4L2_CTRL_TYPE_INTEGER_MENU: + case V4L2_CTRL_TYPE_BITMASK: + if (ret) + return ret; + break; + default: + return -EINVAL; + } + v4l2_ctrl_lock(ctrl); + ctrl->minimum = min; + ctrl->maximum = max; + ctrl->step = step; + ctrl->default_value = def; + c.value = ctrl->cur.val; + if (validate_new(ctrl, &c)) + c.value = def; + if (c.value != ctrl->cur.val) + ret = set_ctrl(NULL, ctrl, &c, V4L2_EVENT_CTRL_CH_RANGE); + else + send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_RANGE); + v4l2_ctrl_unlock(ctrl); + return ret; +} +EXPORT_SYMBOL(v4l2_ctrl_modify_range); + static int v4l2_ctrl_add_event(struct v4l2_subscribed_event *sev, unsigned elems) { struct v4l2_ctrl *ctrl = v4l2_ctrl_find(sev->fh->ctrl_handler, sev->id); diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h index c4cc041..91125b6 100644 --- a/include/media/v4l2-ctrls.h +++ b/include/media/v4l2-ctrls.h @@ -518,6 +518,26 @@ void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); */ void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed); +/** v4l2_ctrl_modify_range() - Update the range of a control. + * @ctrl: The control to update. + * @min: The control's minimum value. + * @max: The control's maximum value. + * @step: The control's step value + * @def: The control's default value. + * + * Update the range of a control on the fly. This works for control types + * INTEGER, BOOLEAN, MENU, INTEGER MENU and BITMASK. For menu controls the + * @step value is interpreted as a menu_skip_mask. + * + * An error is returned if one of the range arguments is invalid for this + * control type. + * + * This function assumes that the control handler is not locked and will + * take the lock itself. + */ +int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, + s32 min, s32 max, u32 step, s32 def); + /** v4l2_ctrl_lock() - Helper function to lock the handler * associated with the control. * @ctrl: The control to lock. diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 94cbe26..928799c 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -1822,6 +1822,7 @@ struct v4l2_event_vsync { /* Payload for V4L2_EVENT_CTRL */ #define V4L2_EVENT_CTRL_CH_VALUE (1 << 0) #define V4L2_EVENT_CTRL_CH_FLAGS (1 << 1) +#define V4L2_EVENT_CTRL_CH_RANGE (1 << 2) struct v4l2_event_ctrl { __u32 changes; -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
