[PATCH v7 0/8] Implement UNIT_CELL_SIZE control

[PATCH v7 0/8] Implement UNIT_CELL_SIZE control

[Ricardo Ribalda Delgado]

UNIT_CELL_SIZE is a control that represents the size of a cell (pixel).
We required a bit of boilerplate to add this control :)
- New way to init compount controls
- New control type

Thanks to Hans, Jacopo and Philipp for your help.

You might want to see the series at my github repository if needed.

https://github.com/ribalda/linux/tree/unit-size-v6

v7: Add new helper v4l2_ctrl_ptr_from_void

v4, v5 of this patchset never reached the mailing list.

Ricardo Ribalda Delgado (8):
  media: v4l2-core: Implement v4l2_ctrl_new_std_compound
  Documentation: v4l2_ctrl_new_std_compound
  media: add V4L2_CTRL_TYPE_AREA control type
  Documentation: media: Document V4L2_CTRL_TYPE_AREA
  media: add V4L2_CID_UNIT_CELL_SIZE control
  Documentation: media: Describe V4L2_CID_UNIT_CELL_SIZE
  media: v4l2-ctrl: Add new helper v4l2_ctrl_ptr_from_void
  media: imx214: Add new control with V4L2_CID_UNIT_CELL_SIZE

 Documentation/media/kapi/v4l2-controls.rst    |  9 +++
 .../media/uapi/v4l/ext-ctrls-image-source.rst |  9 +++
 .../media/uapi/v4l/vidioc-queryctrl.rst       |  6 ++
 drivers/media/i2c/imx214.c                    |  9 +++
 drivers/media/v4l2-core/v4l2-ctrls.c          | 76 +++++++++++++++++--
 include/media/v4l2-ctrls.h                    | 74 ++++++++++++++++++
 include/uapi/linux/v4l2-controls.h            |  1 +
 include/uapi/linux/videodev2.h                |  6 ++
 8 files changed, 183 insertions(+), 7 deletions(-)

-- 
2.23.0

[PATCH v7 1/8] media: v4l2-core: Implement v4l2_ctrl_new_std_compound

[Ricardo Ribalda Delgado]

From: Ricardo Ribalda Delgado <ricardo@ribalda.com>

Currently compound controls do not have a simple way of initializing its
values. This results in ofuscated code with type_ops init.

This patch introduces a new field on the control with the default value
for the compound control that can be set with the brand new
v4l2_ctrl_new_std_compound function

Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Ricardo Ribalda Delgado <ricardo@kernel.org>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 50 ++++++++++++++++++++++++----
 include/media/v4l2-ctrls.h           | 21 ++++++++++++
 2 files changed, 64 insertions(+), 7 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 1d8f38824631..219d8aeefa20 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -29,6 +29,8 @@
 #define call_op(master, op) \
 	(has_op(master, op) ? master->ops->op(master) : 0)
 
+static const union v4l2_ctrl_ptr ptr_null;
+
 /* Internal temporary helper struct, one for each v4l2_ext_control */
 struct v4l2_ctrl_helper {
 	/* Pointer to the control reference of the master control */
@@ -1530,7 +1532,10 @@ static void std_init_compound(const struct v4l2_ctrl *ctrl, u32 idx,
 	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
 	void *p = ptr.p + idx * ctrl->elem_size;
 
-	memset(p, 0, ctrl->elem_size);
+	if (ctrl->p_def.p)
+		memcpy(p, ctrl->p_def.p, ctrl->elem_size);
+	else
+		memset(p, 0, ctrl->elem_size);
 
 	/*
 	 * The cast is needed to get rid of a gcc warning complaining that
@@ -2354,7 +2359,8 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
 			s64 min, s64 max, u64 step, s64 def,
 			const u32 dims[V4L2_CTRL_MAX_DIMS], u32 elem_size,
 			u32 flags, const char * const *qmenu,
-			const s64 *qmenu_int, void *priv)
+			const s64 *qmenu_int, const union v4l2_ctrl_ptr p_def,
+			void *priv)
 {
 	struct v4l2_ctrl *ctrl;
 	unsigned sz_extra;
@@ -2460,6 +2466,9 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
 		 is_array)
 		sz_extra += 2 * tot_ctrl_size;
 
+	if (type >= V4L2_CTRL_COMPOUND_TYPES && p_def.p)
+		sz_extra += elem_size;
+
 	ctrl = kvzalloc(sizeof(*ctrl) + sz_extra, GFP_KERNEL);
 	if (ctrl == NULL) {
 		handler_set_err(hdl, -ENOMEM);
@@ -2503,6 +2512,12 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
 		ctrl->p_new.p = &ctrl->val;
 		ctrl->p_cur.p = &ctrl->cur.val;
 	}
+
+	if (type >= V4L2_CTRL_COMPOUND_TYPES && p_def.p) {
+		ctrl->p_def.p = ctrl->p_cur.p + tot_ctrl_size;
+		memcpy(ctrl->p_def.p, p_def.p, elem_size);
+	}
+
 	for (idx = 0; idx < elems; idx++) {
 		ctrl->type_ops->init(ctrl, idx, ctrl->p_cur);
 		ctrl->type_ops->init(ctrl, idx, ctrl->p_new);
@@ -2554,7 +2569,7 @@ struct v4l2_ctrl *v4l2_ctrl_new_custom(struct v4l2_ctrl_handler *hdl,
 			type, min, max,
 			is_menu ? cfg->menu_skip_mask : step, def,
 			cfg->dims, cfg->elem_size,
-			flags, qmenu, qmenu_int, priv);
+			flags, qmenu, qmenu_int, ptr_null, priv);
 	if (ctrl)
 		ctrl->is_private = cfg->is_private;
 	return ctrl;
@@ -2579,7 +2594,7 @@ struct v4l2_ctrl *v4l2_ctrl_new_std(struct v4l2_ctrl_handler *hdl,
 	}
 	return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
 			     min, max, step, def, NULL, 0,
-			     flags, NULL, NULL, NULL);
+			     flags, NULL, NULL, ptr_null, NULL);
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_std);
 
@@ -2612,7 +2627,7 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu(struct v4l2_ctrl_handler *hdl,
 	}
 	return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
 			     0, max, mask, def, NULL, 0,
-			     flags, qmenu, qmenu_int, NULL);
+			     flags, qmenu, qmenu_int, ptr_null, NULL);
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu);
 
@@ -2644,11 +2659,32 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
 	}
 	return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
 			     0, max, mask, def, NULL, 0,
-			     flags, qmenu, NULL, NULL);
+			     flags, qmenu, NULL, ptr_null, NULL);
 
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_std_menu_items);
 
+/* Helper function for standard compound controls */
+struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
+				const struct v4l2_ctrl_ops *ops, u32 id,
+				const union v4l2_ctrl_ptr p_def)
+{
+	const char *name;
+	enum v4l2_ctrl_type type;
+	u32 flags;
+	s64 min, max, step, def;
+
+	v4l2_ctrl_fill(id, &name, &type, &min, &max, &step, &def, &flags);
+	if (type < V4L2_CTRL_COMPOUND_TYPES) {
+		handler_set_err(hdl, -EINVAL);
+		return NULL;
+	}
+	return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
+			     min, max, step, def, NULL, 0,
+			     flags, NULL, NULL, p_def, NULL);
+}
+EXPORT_SYMBOL(v4l2_ctrl_new_std_compound);
+
 /* Helper function for standard integer menu controls */
 struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 			const struct v4l2_ctrl_ops *ops,
@@ -2669,7 +2705,7 @@ struct v4l2_ctrl *v4l2_ctrl_new_int_menu(struct v4l2_ctrl_handler *hdl,
 	}
 	return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
 			     0, max, 0, def, NULL, 0,
-			     flags, NULL, qmenu_int, NULL);
+			     flags, NULL, qmenu_int, ptr_null, NULL);
 }
 EXPORT_SYMBOL(v4l2_ctrl_new_int_menu);
 
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 570ff4b0205a..90a8ee48c2f3 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -200,6 +200,9 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
  *		not freed when the control is deleted. Should this be needed
  *		then a new internal bitfield can be added to tell the framework
  *		to free this pointer.
+ * @p_def:	The control's default value represented via a union which
+ *		provides a standard way of accessing control types
+ *		through a pointer (for compound controls only).
  * @p_cur:	The control's current value represented via a union which
  *		provides a standard way of accessing control types
  *		through a pointer.
@@ -254,6 +257,7 @@ struct v4l2_ctrl {
 		s32 val;
 	} cur;
 
+	union v4l2_ctrl_ptr p_def;
 	union v4l2_ctrl_ptr p_new;
 	union v4l2_ctrl_ptr p_cur;
 };
@@ -646,6 +650,23 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
 					       u64 mask, u8 def,
 					       const char * const *qmenu);
 
+/**
+ * v4l2_ctrl_new_std_compound() - Allocate and initialize a new standard V4L2
+ *      compound control.
+ *
+ * @hdl:       The control handler.
+ * @ops:       The control ops.
+ * @id:        The control ID.
+ * @p_def:     The control's default value.
+ *
+ * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
+ * to the @p_def field.
+ *
+ */
+struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
+				const struct v4l2_ctrl_ops *ops, u32 id,
+				const union v4l2_ctrl_ptr p_def);
+
 /**
  * v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
  *
-- 
2.23.0

[PATCH v7 2/8] Documentation: v4l2_ctrl_new_std_compound

[Ricardo Ribalda Delgado]

From: Ricardo Ribalda Delgado <ricardo@ribalda.com>

Function for initializing compound controls with a default value.

Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo@kernel.org>
---
 Documentation/media/kapi/v4l2-controls.rst | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/media/kapi/v4l2-controls.rst b/Documentation/media/kapi/v4l2-controls.rst
index ebe2a55908be..b20800cae3f2 100644
--- a/Documentation/media/kapi/v4l2-controls.rst
+++ b/Documentation/media/kapi/v4l2-controls.rst
@@ -140,6 +140,15 @@ Menu controls with a driver specific menu are added by calling
                        const struct v4l2_ctrl_ops *ops, u32 id, s32 max,
                        s32 skip_mask, s32 def, const char * const *qmenu);
 
+Standard compound controls can be added by calling
+:c:func:`v4l2_ctrl_new_std_compound`:
+
+.. code-block:: c
+
+       struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
+                       const struct v4l2_ctrl_ops *ops, u32 id,
+                       const union v4l2_ctrl_ptr p_def);
+
 Integer menu controls with a driver specific menu can be added by calling
 :c:func:`v4l2_ctrl_new_int_menu`:
 
-- 
2.23.0

[PATCH v7 3/8] media: add V4L2_CTRL_TYPE_AREA control type

[Ricardo Ribalda Delgado]

From: Ricardo Ribalda Delgado <ricardo@ribalda.com>

This type contains the width and the height of a rectangular area.

Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo@kernel.org>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 21 ++++++++++++++
 include/media/v4l2-ctrls.h           | 42 ++++++++++++++++++++++++++++
 include/uapi/linux/videodev2.h       |  6 ++++
 3 files changed, 69 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 219d8aeefa20..b9a46f536406 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1678,6 +1678,7 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
 	struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
 	struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
 	void *p = ptr.p + idx * ctrl->elem_size;
+	struct v4l2_area *area;
 
 	switch ((u32)ctrl->type) {
 	case V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS:
@@ -1753,6 +1754,11 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
 		zero_padding(p_vp8_frame_header->entropy_header);
 		zero_padding(p_vp8_frame_header->coder_state);
 		break;
+	case V4L2_CTRL_TYPE_AREA:
+		area = p;
+		if (!area->width || !area->height)
+			return -EINVAL;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -2427,6 +2433,9 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
 	case V4L2_CTRL_TYPE_VP8_FRAME_HEADER:
 		elem_size = sizeof(struct v4l2_ctrl_vp8_frame_header);
 		break;
+	case V4L2_CTRL_TYPE_AREA:
+		elem_size = sizeof(struct v4l2_area);
+		break;
 	default:
 		if (type < V4L2_CTRL_COMPOUND_TYPES)
 			elem_size = sizeof(s32);
@@ -4116,6 +4125,18 @@ int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
 }
 EXPORT_SYMBOL(__v4l2_ctrl_s_ctrl_string);
 
+int __v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+			    const struct v4l2_area *area)
+{
+	lockdep_assert_held(ctrl->handler->lock);
+
+	/* It's a driver bug if this happens. */
+	WARN_ON(ctrl->type != V4L2_CTRL_TYPE_AREA);
+	memcpy(ctrl->p_new.p_area, area, sizeof(*area));
+	return set_ctrl(NULL, ctrl, 0);
+}
+EXPORT_SYMBOL(__v4l2_ctrl_s_ctrl_area);
+
 void v4l2_ctrl_request_complete(struct media_request *req,
 				struct v4l2_ctrl_handler *main_hdl)
 {
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 90a8ee48c2f3..c42f164e2c9e 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -50,6 +50,7 @@ struct poll_table_struct;
  * @p_h264_slice_params:	Pointer to a struct v4l2_ctrl_h264_slice_params.
  * @p_h264_decode_params:	Pointer to a struct v4l2_ctrl_h264_decode_params.
  * @p_vp8_frame_header:		Pointer to a VP8 frame header structure.
+ * @p_area:			Pointer to an area.
  * @p:				Pointer to a compound value.
  */
 union v4l2_ctrl_ptr {
@@ -68,6 +69,7 @@ union v4l2_ctrl_ptr {
 	struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
 	struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
 	struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
+	struct v4l2_area *p_area;
 	void *p;
 };
 
@@ -1086,6 +1088,46 @@ static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
 	return rval;
 }
 
+/**
+ * __v4l2_ctrl_s_ctrl_area() - Unlocked variant of v4l2_ctrl_s_ctrl_area().
+ *
+ * @ctrl:	The control.
+ * @area:	The new area.
+ *
+ * This sets the control's new area safely by going through the control
+ * framework. This function assumes the control's handler is already locked,
+ * allowing it to be used from within the &v4l2_ctrl_ops functions.
+ *
+ * This function is for area type controls only.
+ */
+int __v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+			    const struct v4l2_area *area);
+
+/**
+ * v4l2_ctrl_s_ctrl_area() - Helper function to set a control's area value
+ *	 from within a driver.
+ *
+ * @ctrl:	The control.
+ * @s:		The new area.
+ *
+ * This sets the control's new area safely by going through the control
+ * framework. This function will lock the control's handler, so it cannot be
+ * used from within the &v4l2_ctrl_ops functions.
+ *
+ * This function is for area type controls only.
+ */
+static inline int v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+					const struct v4l2_area *area)
+{
+	int rval;
+
+	v4l2_ctrl_lock(ctrl);
+	rval = __v4l2_ctrl_s_ctrl_area(ctrl, area);
+	v4l2_ctrl_unlock(ctrl);
+
+	return rval;
+}
+
 /* Internal helper functions that deal with control events. */
 extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;
 
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 530638dffd93..b3c0961b62a0 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -422,6 +422,11 @@ struct v4l2_fract {
 	__u32   denominator;
 };
 
+struct v4l2_area {
+	__u32   width;
+	__u32   height;
+};
+
 /**
   * struct v4l2_capability - Describes V4L2 device caps returned by VIDIOC_QUERYCAP
   *
@@ -1720,6 +1725,7 @@ enum v4l2_ctrl_type {
 	V4L2_CTRL_TYPE_U8	     = 0x0100,
 	V4L2_CTRL_TYPE_U16	     = 0x0101,
 	V4L2_CTRL_TYPE_U32	     = 0x0102,
+	V4L2_CTRL_TYPE_AREA          = 0x0106,
 };
 
 /*  Used in the VIDIOC_QUERYCTRL ioctl for querying controls */
-- 
2.23.0

[PATCH v7 4/8] Documentation: media: Document V4L2_CTRL_TYPE_AREA

[Ricardo Ribalda Delgado]

A struct v4l2_area containing the width and the height of a rectangular
area.

Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 Documentation/media/uapi/v4l/vidioc-queryctrl.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
index a3d56ffbf4cc..33aff21b7d11 100644
--- a/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
+++ b/Documentation/media/uapi/v4l/vidioc-queryctrl.rst
@@ -443,6 +443,12 @@ See also the examples in :ref:`control`.
       - n/a
       - A struct :c:type:`v4l2_ctrl_mpeg2_quantization`, containing MPEG-2
 	quantization matrices for stateless video decoders.
+    * - ``V4L2_CTRL_TYPE_AREA``
+      - n/a
+      - n/a
+      - n/a
+      - A struct :c:type:`v4l2_area`, containing the width and the height
+        of a rectangular area. Units depend on the use case.
     * - ``V4L2_CTRL_TYPE_H264_SPS``
       - n/a
       - n/a
-- 
2.23.0

[PATCH v7 5/8] media: add V4L2_CID_UNIT_CELL_SIZE control

[Ricardo Ribalda Delgado]

This control returns the unit cell size in nanometres. The struct provides
the width and the height in separated fields to take into consideration
asymmetric pixels and/or hardware binning.
This control is required for automatic calibration of sensors/cameras.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 drivers/media/v4l2-core/v4l2-ctrls.c | 5 +++++
 include/uapi/linux/v4l2-controls.h   | 1 +
 2 files changed, 6 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index b9a46f536406..f626f9983408 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -996,6 +996,7 @@ const char *v4l2_ctrl_get_name(u32 id)
 	case V4L2_CID_AUTO_FOCUS_RANGE:		return "Auto Focus, Range";
 	case V4L2_CID_PAN_SPEED:		return "Pan, Speed";
 	case V4L2_CID_TILT_SPEED:		return "Tilt, Speed";
+	case V4L2_CID_UNIT_CELL_SIZE:		return "Unit Cell Size";
 
 	/* FM Radio Modulator controls */
 	/* Keep the order of the 'case's the same as in v4l2-controls.h! */
@@ -1377,6 +1378,10 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
 	case V4L2_CID_MPEG_VIDEO_VP8_FRAME_HEADER:
 		*type = V4L2_CTRL_TYPE_VP8_FRAME_HEADER;
 		break;
+	case V4L2_CID_UNIT_CELL_SIZE:
+		*type = V4L2_CTRL_TYPE_AREA;
+		*flags |= V4L2_CTRL_FLAG_READ_ONLY;
+		break;
 	default:
 		*type = V4L2_CTRL_TYPE_INTEGER;
 		break;
diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index a2669b79b294..5a7bedee2b0e 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h
@@ -1034,6 +1034,7 @@ enum v4l2_jpeg_chroma_subsampling {
 #define V4L2_CID_TEST_PATTERN_GREENR		(V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 5)
 #define V4L2_CID_TEST_PATTERN_BLUE		(V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 6)
 #define V4L2_CID_TEST_PATTERN_GREENB		(V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 7)
+#define V4L2_CID_UNIT_CELL_SIZE			(V4L2_CID_IMAGE_SOURCE_CLASS_BASE + 8)
 
 
 /* Image processing controls */
-- 
2.23.0

[PATCH v7 6/8] Documentation: media: Describe V4L2_CID_UNIT_CELL_SIZE

[Ricardo Ribalda Delgado]

New control to pass to userspace the width/height of a pixel. Which is
needed for calibration and lens selection.

Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 Documentation/media/uapi/v4l/ext-ctrls-image-source.rst | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/media/uapi/v4l/ext-ctrls-image-source.rst b/Documentation/media/uapi/v4l/ext-ctrls-image-source.rst
index 2c3ab5796d76..033672dcb43d 100644
--- a/Documentation/media/uapi/v4l/ext-ctrls-image-source.rst
+++ b/Documentation/media/uapi/v4l/ext-ctrls-image-source.rst
@@ -55,3 +55,12 @@ Image Source Control IDs
 
 ``V4L2_CID_TEST_PATTERN_GREENB (integer)``
     Test pattern green (next to blue) colour component.
+
+``V4L2_CID_UNIT_CELL_SIZE (struct)``
+    This control returns the unit cell size in nanometres. The struct
+    :c:type:`v4l2_area` provides the width and the height in separated
+    fields to take into consideration asymmetric pixels and/or hardware
+    binning.
+    The unit cell consists of the whole area of the pixel, sensitive and
+    non-sensitive.
+    This control is required for automatic calibration sensors/cameras.
-- 
2.23.0

[PATCH v7 7/8] media: v4l2-ctrl: Add new helper v4l2_ctrl_ptr_from_void

[Ricardo Ribalda Delgado]

This helper function simplifies the code by not needing a union
v4l2_ctrl_ptr and an assignment every time we need to use
a ctrl_ptr.

Suggested-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 include/media/v4l2-ctrls.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index c42f164e2c9e..d69cfdffd41d 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -73,6 +73,17 @@ union v4l2_ctrl_ptr {
 	void *p;
 };
 
+/**
+ * v4l2_ctrl_ptr() - Helper function to return a v4l2_ctrl_ptr from a
+ * void pointer
+ * @ptr:	The void pointer
+ */
+static inline union v4l2_ctrl_ptr v4l2_ctrl_ptr_from_void(void *ptr)
+{
+	BUILD_BUG_ON(sizeof(union v4l2_ctrl_ptr) != sizeof(void *));
+	return (union v4l2_ctrl_ptr) ptr;
+}
+
 /**
  * struct v4l2_ctrl_ops - The control operations that the driver has to provide.
  *
-- 
2.23.0

[PATCH v7 8/8] media: imx214: Add new control with V4L2_CID_UNIT_CELL_SIZE

[Ricardo Ribalda Delgado]

According to the product brief, the unit cell size is 1120 nanometers^2.

https://www.sony-semicon.co.jp/products_en/IS/sensor1/img/products/ProductBrief_IMX214_20150428.pdf

Signed-off-by: Ricardo Ribalda Delgado <ribalda@kernel.org>
---
 drivers/media/i2c/imx214.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/media/i2c/imx214.c b/drivers/media/i2c/imx214.c
index 159a3a604f0e..4d9879f60dfb 100644
--- a/drivers/media/i2c/imx214.c
+++ b/drivers/media/i2c/imx214.c
@@ -47,6 +47,7 @@ struct imx214 {
 	struct v4l2_ctrl *pixel_rate;
 	struct v4l2_ctrl *link_freq;
 	struct v4l2_ctrl *exposure;
+	struct v4l2_ctrl *unit_size;
 
 	struct regulator_bulk_data	supplies[IMX214_NUM_SUPPLIES];
 
@@ -948,6 +949,10 @@ static int imx214_probe(struct i2c_client *client)
 	static const s64 link_freq[] = {
 		IMX214_DEFAULT_LINK_FREQ,
 	};
+	static const struct v4l2_area unit_size = {
+		.width = 1120,
+		.height = 1120,
+	};
 	int ret;
 
 	ret = imx214_parse_fwnode(dev);
@@ -1029,6 +1034,10 @@ static int imx214_probe(struct i2c_client *client)
 					     V4L2_CID_EXPOSURE,
 					     0, 3184, 1, 0x0c70);
 
+	imx214->unit_size = v4l2_ctrl_new_std_compound(&imx214->ctrls,
+				NULL,
+				V4L2_CID_UNIT_CELL_SIZE,
+				v4l2_ctrl_ptr_from_void((void *)&unit_size));
 	ret = imx214->ctrls.error;
 	if (ret) {
 		dev_err(&client->dev, "%s control init failed (%d)\n",
-- 
2.23.0