From 953eae5d8d7492a9200aaee0a60cc0838e7a2cfe Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Date: Thu, 29 Oct 2015 08:10:29 -0200 Subject: [PATCH] [media] media/v4l2-core: struct struct v4l2_ext_controls param which Support for new field which on v4l2_ext_controls, used to get the default value of one or more controls. Signed-off-by: Ricardo Ribalda Delgado Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-ctrls.c | 34 ++++++++++++++++++++++++---- 1 file changed, 29 insertions(+), 5 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index f3fba8661166..c9d5537b6af7 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -1491,6 +1491,17 @@ static int new_to_user(struct v4l2_ext_control *c, return ptr_to_user(c, ctrl, ctrl->p_new); } +/* Helper function: copy the initial control value back to the caller */ +static int def_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl) +{ + int idx; + + for (idx = 0; idx < ctrl->elems; idx++) + ctrl->type_ops->init(ctrl, idx, ctrl->p_new); + + return ptr_to_user(c, ctrl, ctrl->p_new); +} + /* Helper function: copy the caller-provider value to the given control value */ static int user_to_ptr(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl, @@ -2710,7 +2721,9 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, cs->error_idx = i; - if (cs->which && V4L2_CTRL_ID2WHICH(id) != cs->which) + if (cs->which && + cs->which != V4L2_CTRL_WHICH_DEF_VAL && + V4L2_CTRL_ID2WHICH(id) != cs->which) return -EINVAL; /* Old-style private controls are not allowed for @@ -2789,7 +2802,7 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl, whether there are any controls at all. */ static int class_check(struct v4l2_ctrl_handler *hdl, u32 which) { - if (!which) + if (which == 0 || which == V4L2_CTRL_WHICH_DEF_VAL) return list_empty(&hdl->ctrl_refs) ? -EINVAL : 0; return find_ref_lock(hdl, which | 1) ? 0 : -EINVAL; } @@ -2803,6 +2816,9 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs struct v4l2_ctrl_helper *helpers = helper; int ret; int i, j; + bool def_value; + + def_value = (cs->which == V4L2_CTRL_WHICH_DEF_VAL); cs->error_idx = cs->count; cs->which = V4L2_CTRL_ID2WHICH(cs->which); @@ -2829,9 +2845,11 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs for (i = 0; !ret && i < cs->count; i++) { int (*ctrl_to_user)(struct v4l2_ext_control *c, - struct v4l2_ctrl *ctrl) = cur_to_user; + struct v4l2_ctrl *ctrl); struct v4l2_ctrl *master; + ctrl_to_user = def_value ? def_to_user : cur_to_user; + if (helpers[i].mref == NULL) continue; @@ -2841,8 +2859,9 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs v4l2_ctrl_lock(master); /* g_volatile_ctrl will update the new control values */ - if ((master->flags & V4L2_CTRL_FLAG_VOLATILE) || - (master->has_volatiles && !is_cur_manual(master))) { + if (!def_value && + ((master->flags & V4L2_CTRL_FLAG_VOLATILE) || + (master->has_volatiles && !is_cur_manual(master)))) { for (j = 0; j < master->ncontrols; j++) cur_to_new(master->cluster[j]); ret = call_op(master, g_volatile_ctrl); @@ -3064,6 +3083,11 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, struct v4l2_ctrl_handler *hdl, int ret; cs->error_idx = cs->count; + + /* Default value cannot be changed */ + if (cs->which == V4L2_CTRL_WHICH_DEF_VAL) + return -EINVAL; + cs->which = V4L2_CTRL_ID2WHICH(cs->which); if (hdl == NULL) -- 2.20.1