[PATCH v14 08/11] media: uvcvideo: support V4L2_CTRL_WHICH_MIN/MAX_VAL

[Yunke Cao <yunkec@google.com>]

Add support for V4L2_CTRL_WHICH_MIN/MAX_VAL in uvc driver.
It is useful for the V4L2_CID_UVC_REGION_OF_INTEREST_RECT control.

Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Yunke Cao <yunkec@google.com>
---
Changelog since v11:
- No change.
Changelog since v10:
- Added Reviewed-by from Sergey.
Changelog since v9:
- Revert a change in v7 that causes v4l2-compliance failure:
- In uvc_ioctl_g_ext_ctrls(), when v4l2_which is not V4L2_CTRL_WHICH_*_VAL,
- treat it the same as cur instead of returning EINVAL. This is the existing
- behavior.
- The change in v7 of returning EINVAL fails the check in
- v4l2-compliance/v4l2-test-controls.cpp#L834.
Changelog since v8:
- No change.
Changelog since v7:
- Address some comments.

 drivers/media/usb/uvc/uvc_ctrl.c | 64 +++++++++++++++++++++++++++-----
 drivers/media/usb/uvc/uvc_v4l2.c |  7 +++-
 drivers/media/usb/uvc/uvcvideo.h |  3 +-
 3 files changed, 61 insertions(+), 13 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index aae2480496b7..c073c2a02102 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -1247,11 +1247,18 @@ int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
 	if (!ctrl)
 		return -EINVAL;
 
-	if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) && read)
-		return -EACCES;
-
-	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR) && !read)
-		return -EACCES;
+	if (read) {
+		if (ctrls->which == V4L2_CTRL_WHICH_MIN_VAL ||
+		    ctrls->which == V4L2_CTRL_WHICH_MAX_VAL) {
+			if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) ||
+			    !(ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX))
+				return -EINVAL;
+		} else if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
+			return -EACCES;
+	} else {
+		if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
+			return -EACCES;
+	}
 
 	if (ioctl != VIDIOC_S_EXT_CTRLS || !mapping->master_id)
 		return 0;
@@ -1332,6 +1339,9 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
 		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
 	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
 		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+	if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX) &&
+	    (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN))
+		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_HAS_WHICH_MIN_MAX;
 
 	if (mapping->master_id)
 		__uvc_find_control(ctrl->entity, mapping->master_id,
@@ -1981,6 +1991,7 @@ int uvc_ctrl_get(struct uvc_video_chain *chain,
 static int __uvc_ctrl_get_boundary_std(struct uvc_video_chain *chain,
 				       struct uvc_control *ctrl,
 				       struct uvc_control_mapping *mapping,
+				       u32 v4l2_which,
 				       struct v4l2_ext_control *xctrl)
 {
 	struct v4l2_queryctrl qc = { .id = xctrl->id };
@@ -1990,28 +2001,59 @@ static int __uvc_ctrl_get_boundary_std(struct uvc_video_chain *chain,
 	if (ret < 0)
 		return ret;
 
-	xctrl->value = qc.default_value;
+	switch (v4l2_which) {
+	case V4L2_CTRL_WHICH_DEF_VAL:
+		xctrl->value = qc.default_value;
+		break;
+	case V4L2_CTRL_WHICH_MIN_VAL:
+		xctrl->value = qc.minimum;
+		break;
+	case V4L2_CTRL_WHICH_MAX_VAL:
+		xctrl->value = qc.maximum;
+		break;
+	}
+
 	return 0;
 }
 
 static int __uvc_ctrl_get_boundary_compound(struct uvc_video_chain *chain,
 					    struct uvc_control *ctrl,
 					    struct uvc_control_mapping *mapping,
+					    u32 v4l2_which,
 					    struct v4l2_ext_control *xctrl)
 {
+	u32 flag, id;
 	int ret;
 
+	switch (v4l2_which) {
+	case V4L2_CTRL_WHICH_DEF_VAL:
+		flag = UVC_CTRL_FLAG_GET_DEF;
+		id = UVC_CTRL_DATA_DEF;
+		break;
+	case V4L2_CTRL_WHICH_MIN_VAL:
+		flag = UVC_CTRL_FLAG_GET_MIN;
+		id = UVC_CTRL_DATA_MIN;
+		break;
+	case V4L2_CTRL_WHICH_MAX_VAL:
+		flag = UVC_CTRL_FLAG_GET_MAX;
+		id = UVC_CTRL_DATA_MAX;
+		break;
+	}
+
+	if (!(ctrl->info.flags & flag) && flag != UVC_CTRL_FLAG_GET_DEF)
+		return -EINVAL;
+
 	if (!ctrl->cached) {
 		ret = uvc_ctrl_populate_cache(chain, ctrl);
 		if (ret < 0)
 			return ret;
 	}
 
-	return __uvc_ctrl_get_compound(mapping, ctrl, UVC_CTRL_DATA_DEF, xctrl);
+	return __uvc_ctrl_get_compound(mapping, ctrl, id, xctrl);
 }
 
 int uvc_ctrl_get_boundary(struct uvc_video_chain *chain,
-			  struct v4l2_ext_control *xctrl)
+			  struct v4l2_ext_control *xctrl, u32 v4l2_which)
 {
 	struct uvc_control *ctrl;
 	struct uvc_control_mapping *mapping;
@@ -2028,9 +2070,11 @@ int uvc_ctrl_get_boundary(struct uvc_video_chain *chain,
 
 	if (uvc_ctrl_mapping_is_compound(mapping))
 		ret = __uvc_ctrl_get_boundary_compound(chain, ctrl, mapping,
-						       xctrl);
+						       v4l2_which, xctrl);
 	else
-		ret = __uvc_ctrl_get_boundary_std(chain, ctrl, mapping, xctrl);
+		ret = __uvc_ctrl_get_boundary_std(chain, ctrl, mapping,
+						  v4l2_which, xctrl);
+
 
 done:
 	mutex_unlock(&chain->ctrl_mutex);
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index ff72caf7bc9e..352f62ef02f2 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -1094,9 +1094,12 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
 	if (ret < 0)
 		return ret;
 
-	if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
+	switch (ctrls->which) {
+	case V4L2_CTRL_WHICH_DEF_VAL:
+	case V4L2_CTRL_WHICH_MIN_VAL:
+	case V4L2_CTRL_WHICH_MAX_VAL:
 		for (i = 0; i < ctrls->count; ++ctrl, ++i) {
-			ret = uvc_ctrl_get_boundary(chain, ctrl);
+			ret = uvc_ctrl_get_boundary(chain, ctrl, ctrls->which);
 			if (ret < 0) {
 				ctrls->error_idx = i;
 				return ret;
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 11805b729c22..6fda40919e7f 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -790,7 +790,8 @@ static inline int uvc_ctrl_rollback(struct uvc_fh *handle)
 
 int uvc_ctrl_get(struct uvc_video_chain *chain, struct v4l2_ext_control *xctrl);
 int uvc_ctrl_get_boundary(struct uvc_video_chain *chain,
-			  struct v4l2_ext_control *xctrl);
+			  struct v4l2_ext_control *xctrl,
+			  u32 v4l2_which);
 int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
 int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
 			   const struct v4l2_ext_controls *ctrls,
-- 
2.43.0.rc2.451.g8631bc7472-goog