[PATCH v9 08/11] v4l2-ctrls: add support for V4L2_CTRL_WHICH_MIN/MAX_VAL

Yunke Cao
2022-10-25T05:56:25Z

From: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Add the capability of retrieving the min and max values of a
compound control.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Yunke Cao <yunkec@google.com>
---
Changelog since v8:
- Return ENODATA when min/max is not implemented. Document this behavior.
- Created a shared helper function __v4l2_ctrl_type_op_init that takes "which"
as a parameter. Call it in def, min and max operations.
Changelog since v7:
- Document that the definition of the min/max are provided by compound controls
are defined in control documentation.
- Return error, instead of zeroed memory for v4l2_ctrl_ptr_create(NULL).

git am from https://lore.kernel.org/all/20191119113457.57833-3-hverkuil-cisco@xs4all.nl/
- Fixed some merge conflits.
- Fixed the build error in drivers/media/platform/qcom/venus.
.../media/v4l/vidioc-g-ext-ctrls.rst | 11 +-
.../media/videodev2.h.rst.exceptions | 2 +
drivers/media/i2c/imx214.c | 5 +-
.../media/platform/qcom/venus/venc_ctrls.c | 9 +-
drivers/media/v4l2-core/v4l2-ctrls-api.c | 57 +++++--
drivers/media/v4l2-core/v4l2-ctrls-core.c | 156 +++++++++++++++---
drivers/media/v4l2-core/v4l2-ioctl.c | 4 +-
include/media/v4l2-ctrls.h | 34 +++-
include/uapi/linux/videodev2.h | 2 +
9 files changed, 236 insertions(+), 44 deletions(-)

diff --git a/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst b/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
index 927ef397f1ce..1cc21ee229aa 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst
@@ -304,14 +304,21 @@ still cause this situation.
- Which value of the control to get/set/try.
* - :cspan:`2` ``V4L2_CTRL_WHICH_CUR_VAL`` will return the current value of
the control, ``V4L2_CTRL_WHICH_DEF_VAL`` will return the default
+ value of the control, ``V4L2_CTRL_WHICH_MIN_VAL`` will return the minimum
+ value of the control, ``V4L2_CTRL_WHICH_MAX_VAL`` will return the maximum
value of the control and ``V4L2_CTRL_WHICH_REQUEST_VAL`` indicates that
these controls have to be retrieved from a request or tried/set for
a request. In the latter case the ``request_fd`` field contains the
file descriptor of the request that should be used. If the device
does not support requests, then ``EACCES`` will be returned.

- When using ``V4L2_CTRL_WHICH_DEF_VAL`` be aware that you can only
- get the default value of the control, you cannot set or try it.
+ When using ``V4L2_CTRL_WHICH_DEF_VAL``, ``V4L2_CTRL_WHICH_MIN_VAL``
+ or ``V4L2_CTRL_WHICH_MAX_VAL`` be aware that you can only get the
+ default/minimum/maximum value of the control, you cannot set or try it.
+ The definition of minimum/maximum values for compound types are provided by
+ the control documentation. If the control documentation does not
+ document the meaning of minimum/maximum value, then it is not supported.
+ Querying its minmimum/maximum value will result in -ENODATA.

For backwards compatibility you can also use a control class here
(see :ref:`ctrl-class`). In that case all controls have to
diff --git a/Documentation/userspace-api/media/videodev2.h.rst.exceptions b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
index 828cca8e2daa..6295b0fa5716 100644
--- a/Documentation/userspace-api/media/videodev2.h.rst.exceptions
+++ b/Documentation/userspace-api/media/videodev2.h.rst.exceptions
@@ -563,6 +563,8 @@ ignore define V4L2_CTRL_DRIVER_PRIV
ignore define V4L2_CTRL_MAX_DIMS
ignore define V4L2_CTRL_WHICH_CUR_VAL
ignore define V4L2_CTRL_WHICH_DEF_VAL
+ignore define V4L2_CTRL_WHICH_MIN_VAL
+ignore define V4L2_CTRL_WHICH_MAX_VAL
ignore define V4L2_CTRL_WHICH_REQUEST_VAL
ignore define V4L2_OUT_CAP_CUSTOM_TIMINGS
ignore define V4L2_CID_MAX_CTRLS
diff --git a/drivers/media/i2c/imx214.c b/drivers/media/i2c/imx214.c
index 710c9fb515fd..bd11bd8105aa 100644
--- a/drivers/media/i2c/imx214.c
+++ b/drivers/media/i2c/imx214.c
@@ -1037,7 +1037,10 @@ static int imx214_probe(struct i2c_client *client)
imx214->unit_size = v4l2_ctrl_new_std_compound(&imx214->ctrls,
NULL,
V4L2_CID_UNIT_CELL_SIZE,
- v4l2_ctrl_ptr_create((void *)&unit_size));
+ v4l2_ctrl_ptr_create((void *)&unit_size),
+ v4l2_ctrl_ptr_create(NULL),
+ v4l2_ctrl_ptr_create(NULL));
+
ret = imx214->ctrls.error;
if (ret) {
dev_err(&client->dev, "%s control init failed (%d)\n",
diff --git a/drivers/media/platform/qcom/venus/venc_ctrls.c b/drivers/media/platform/qcom/venus/venc_ctrls.c
index 7468e43800a9..28eca8f9d148 100644
--- a/drivers/media/platform/qcom/venus/venc_ctrls.c
+++ b/drivers/media/platform/qcom/venus/venc_ctrls.c
@@ -607,11 +607,16 @@ int venc_ctrl_init(struct venus_inst *inst)

v4l2_ctrl_new_std_compound(&inst->ctrl_handler, &venc_ctrl_ops,
V4L2_CID_COLORIMETRY_HDR10_CLL_INFO,
- v4l2_ctrl_ptr_create(&p_hdr10_cll));
+ v4l2_ctrl_ptr_create(&p_hdr10_cll),
+ v4l2_ctrl_ptr_create(NULL),
+ v4l2_ctrl_ptr_create(NULL));

v4l2_ctrl_new_std_compound(&inst->ctrl_handler, &venc_ctrl_ops,
V4L2_CID_COLORIMETRY_HDR10_MASTERING_DISPLAY,
- v4l2_ctrl_ptr_create((void *)&p_hdr10_mastering));
+ v4l2_ctrl_ptr_create((void *)&p_hdr10_mastering),
+ v4l2_ctrl_ptr_create(NULL),
+ v4l2_ctrl_ptr_create(NULL));
+

v4l2_ctrl_new_std_menu(&inst->ctrl_handler, &venc_ctrl_ops,
V4L2_CID_MPEG_VIDEO_INTRA_REFRESH_PERIOD_TYPE,
diff --git a/drivers/media/v4l2-core/v4l2-ctrls-api.c b/drivers/media/v4l2-core/v4l2-ctrls-api.c
index d0a3aa3806fb..3bfab11fe148 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-api.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-api.c
@@ -94,6 +94,34 @@ static int def_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
return ptr_to_user(c, ctrl, ctrl->p_new);
}

+/* Helper function: copy the minimum control value back to the caller */
+static int min_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
+{
+ int idx, ret;
+
+ for (idx = 0; idx < ctrl->elems; idx++) {
+ ret = ctrl->type_ops->minimum(ctrl, idx, ctrl->p_new);
+ if (ret)
+ return ret;
+ }
+
+ return ptr_to_user(c, ctrl, ctrl->p_new);
+}
+
+/* Helper function: copy the maximum control value back to the caller */
+static int max_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
+{
+ int idx, ret;
+
+ for (idx = 0; idx < ctrl->elems; idx++) {
+ ret = ctrl->type_ops->maximum(ctrl, idx, ctrl->p_new);
+ if (ret)
+ return ret;
+ }
+
+ return ptr_to_user(c, ctrl, ctrl->p_new);
+}
+
/* Helper function: copy the caller-provider value as the new control value */
static int user_to_new(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
{
@@ -228,8 +256,8 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
cs->error_idx = i;

if (cs->which &&
- cs->which != V4L2_CTRL_WHICH_DEF_VAL &&
- cs->which != V4L2_CTRL_WHICH_REQUEST_VAL &&
+ (cs->which < V4L2_CTRL_WHICH_DEF_VAL ||
+ cs->which > V4L2_CTRL_WHICH_MAX_VAL) &&
V4L2_CTRL_ID2WHICH(id) != cs->which) {
dprintk(vdev,
"invalid which 0x%x or control id 0x%x\n",
@@ -367,8 +395,8 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler *hdl,
*/
static int class_check(struct v4l2_ctrl_handler *hdl, u32 which)
{
- if (which == 0 || which == V4L2_CTRL_WHICH_DEF_VAL ||
- which == V4L2_CTRL_WHICH_REQUEST_VAL)
+ if (which == 0 || (which >= V4L2_CTRL_WHICH_DEF_VAL &&
+ which <= V4L2_CTRL_WHICH_MAX_VAL))
return 0;
return find_ref_lock(hdl, which | 1) ? 0 : -EINVAL;
}
@@ -388,10 +416,12 @@ int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl,
struct v4l2_ctrl_helper *helpers = helper;
int ret;
int i, j;
- bool is_default, is_request;
+ bool is_default, is_request, is_min, is_max;

is_default = (cs->which == V4L2_CTRL_WHICH_DEF_VAL);
is_request = (cs->which == V4L2_CTRL_WHICH_REQUEST_VAL);
+ is_min = (cs->which == V4L2_CTRL_WHICH_MIN_VAL);
+ is_max = (cs->which == V4L2_CTRL_WHICH_MAX_VAL);

cs->error_idx = cs->count;
cs->which = V4L2_CTRL_ID2WHICH(cs->which);
@@ -431,13 +461,14 @@ int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl,

/*
* g_volatile_ctrl will update the new control values.
- * This makes no sense for V4L2_CTRL_WHICH_DEF_VAL and
+ * This makes no sense for V4L2_CTRL_WHICH_DEF_VAL,
+ * V4L2_CTRL_WHICH_MIN_VAL, V4L2_CTRL_WHICH_MAX_VAL and
* V4L2_CTRL_WHICH_REQUEST_VAL. In the case of requests
* it is v4l2_ctrl_request_complete() that copies the
* volatile controls at the time of request completion
* to the request, so you don't want to do that again.
*/
- if (!is_default && !is_request &&
+ if (!is_default && !is_request && !is_min && !is_max &&
((master->flags & V4L2_CTRL_FLAG_VOLATILE) ||
(master->has_volatiles && !is_cur_manual(master)))) {
for (j = 0; j < master->ncontrols; j++)
@@ -466,6 +497,10 @@ int v4l2_g_ext_ctrls_common(struct v4l2_ctrl_handler *hdl,
ret = -ENOMEM;
else if (is_request && ref->p_req_valid)
ret = req_to_user(cs->controls + idx, ref);
+ else if (is_min)
+ ret = min_to_user(cs->controls + idx, ref->ctrl);
+ else if (is_max)
+ ret = max_to_user(cs->controls + idx, ref->ctrl);
else if (is_volatile)
ret = new_to_user(cs->controls + idx, ref->ctrl);
else
@@ -563,9 +598,11 @@ int try_set_ext_ctrls_common(struct v4l2_fh *fh,

cs->error_idx = cs->count;

- /* Default value cannot be changed */
- if (cs->which == V4L2_CTRL_WHICH_DEF_VAL) {
- dprintk(vdev, "%s: cannot change default value\n",
+ /* Default/minimum/maximum values cannot be changed */
+ if (cs->which == V4L2_CTRL_WHICH_DEF_VAL ||
+ cs->which == V4L2_CTRL_WHICH_MIN_VAL ||
+ cs->which == V4L2_CTRL_WHICH_MAX_VAL) {
+ dprintk(vdev, "%s: cannot change default/min/max value\n",
video_device_node_name(vdev));
return -EINVAL;
}
diff --git a/drivers/media/v4l2-core/v4l2-ctrls-core.c b/drivers/media/v4l2-core/v4l2-ctrls-core.c
index 0ac36ebc45dd..f8de0a974f16 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-core.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-core.c
@@ -177,29 +177,72 @@ static void std_init_compound(const struct v4l2_ctrl *ctrl, u32 idx,
}
}

-void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
+static int std_min_compound(const struct v4l2_ctrl *ctrl, u32 idx,
union v4l2_ctrl_ptr ptr)
+{
+ void *p = ptr.p + idx * ctrl->elem_size;
+
+ if (!ctrl->p_min.p_const)
+ return -ENODATA;
+
+ memcpy(p, ctrl->p_min.p_const, ctrl->elem_size);
+ return 0;
+}
+
+static int std_max_compound(const struct v4l2_ctrl *ctrl, u32 idx,
+ union v4l2_ctrl_ptr ptr)
+{
+ void *p = ptr.p + idx * ctrl->elem_size;
+
+ if (!ctrl->p_max.p_const)
+ return -ENODATA;
+
+ memcpy(p, ctrl->p_max.p_const, ctrl->elem_size);
+ return 0;
+}
+
+static int __v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
+ u32 which, union v4l2_ctrl_ptr ptr)
{
unsigned int i;
u32 tot_elems = ctrl->elems;
u32 elems = tot_elems - from_idx;
+ s64 value;
+ int ret;

if (from_idx >= tot_elems)
- return;
+ return -EINVAL;
+
+ switch (which) {
+ case V4L2_CTRL_WHICH_DEF_VAL:
+ value = ctrl->default_value;
+ break;
+ case V4L2_CTRL_WHICH_MAX_VAL:
+ value = ctrl->maximum;
+ break;
+ case V4L2_CTRL_WHICH_MIN_VAL:
+ value = ctrl->minimum;
+ break;
+ default:
+ return -EINVAL;
+ }

switch (ctrl->type) {
case V4L2_CTRL_TYPE_STRING:
+ if (which == V4L2_CTRL_WHICH_DEF_VAL)
+ value = ctrl->minimum;
+
for (i = from_idx; i < tot_elems; i++) {
unsigned int offset = i * ctrl->elem_size;

- memset(ptr.p_char + offset, ' ', ctrl->minimum);
- ptr.p_char[offset + ctrl->minimum] = '\0';
+ memset(ptr.p_char + offset, ' ', value);
+ ptr.p_char[offset + value] = '\0';
}
break;
case V4L2_CTRL_TYPE_INTEGER64:
- if (ctrl->default_value) {
+ if (value) {
for (i = from_idx; i < tot_elems; i++)
- ptr.p_s64[i] = ctrl->default_value;
+ ptr.p_s64[i] = value;
} else {
memset(ptr.p_s64 + from_idx, 0, elems * sizeof(s64));
}
@@ -209,9 +252,9 @@ void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
case V4L2_CTRL_TYPE_MENU:
case V4L2_CTRL_TYPE_BITMASK:
case V4L2_CTRL_TYPE_BOOLEAN:
- if (ctrl->default_value) {
+ if (value) {
for (i = from_idx; i < tot_elems; i++)
- ptr.p_s32[i] = ctrl->default_value;
+ ptr.p_s32[i] = value;
} else {
memset(ptr.p_s32 + from_idx, 0, elems * sizeof(s32));
}
@@ -221,32 +264,69 @@ void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
memset(ptr.p_s32 + from_idx, 0, elems * sizeof(s32));
break;
case V4L2_CTRL_TYPE_U8:
- memset(ptr.p_u8 + from_idx, ctrl->default_value, elems);
+ memset(ptr.p_u8 + from_idx, value, elems);
break;
case V4L2_CTRL_TYPE_U16:
- if (ctrl->default_value) {
+ if (value) {
for (i = from_idx; i < tot_elems; i++)
- ptr.p_u16[i] = ctrl->default_value;
+ ptr.p_u16[i] = value;
} else {
memset(ptr.p_u16 + from_idx, 0, elems * sizeof(u16));
}
break;
case V4L2_CTRL_TYPE_U32:
- if (ctrl->default_value) {
+ if (value) {
for (i = from_idx; i < tot_elems; i++)
- ptr.p_u32[i] = ctrl->default_value;
+ ptr.p_u32[i] = value;
} else {
memset(ptr.p_u32 + from_idx, 0, elems * sizeof(u32));
}
break;
default:
- for (i = from_idx; i < tot_elems; i++)
- std_init_compound(ctrl, i, ptr);
+ for (i = from_idx; i < tot_elems; i++) {
+ switch (which) {
+ case V4L2_CTRL_WHICH_DEF_VAL:
+ std_init_compound(ctrl, i, ptr);
+ break;
+ case V4L2_CTRL_WHICH_MAX_VAL:
+ ret = std_max_compound(ctrl, i, ptr);
+ if (ret)
+ return ret;
+ break;
+ case V4L2_CTRL_WHICH_MIN_VAL:
+ ret = std_min_compound(ctrl, i, ptr);
+ if (ret)
+ return ret;
+ break;
+ }
+ }
break;
}
+
+ return 0;
+}
+
+void v4l2_ctrl_type_op_init(const struct v4l2_ctrl *ctrl, u32 from_idx,
+ union v4l2_ctrl_ptr ptr)
+{
+ __v4l2_ctrl_type_op_init(ctrl, from_idx, V4L2_CTRL_WHICH_DEF_VAL, ptr);
}
EXPORT_SYMBOL(v4l2_ctrl_type_op_init);

+static int v4l2_ctrl_type_op_minimum(const struct v4l2_ctrl *ctrl, u32 from_idx,
+ union v4l2_ctrl_ptr ptr)
+{
+ return __v4l2_ctrl_type_op_init(ctrl, from_idx,
+ V4L2_CTRL_WHICH_MIN_VAL, ptr);
+}
+
+static int v4l2_ctrl_type_op_maximum(const struct v4l2_ctrl *ctrl, u32 from_idx,
+ union v4l2_ctrl_ptr ptr)
+{
+ return __v4l2_ctrl_type_op_init(ctrl, from_idx,
+ V4L2_CTRL_WHICH_MAX_VAL, ptr);
+}
+
void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl)
{
union v4l2_ctrl_ptr ptr = ctrl->p_cur;
@@ -1043,6 +1123,8 @@ EXPORT_SYMBOL(v4l2_ctrl_type_op_validate);
static const struct v4l2_ctrl_type_ops std_type_ops = {
.equal = v4l2_ctrl_type_op_equal,
.init = v4l2_ctrl_type_op_init,
+ .minimum = v4l2_ctrl_type_op_minimum,
+ .maximum = v4l2_ctrl_type_op_maximum,
.log = v4l2_ctrl_type_op_log,
.validate = v4l2_ctrl_type_op_validate,
};
@@ -1514,7 +1596,10 @@ 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, const union v4l2_ctrl_ptr p_def,
+ const s64 *qmenu_int,
+ const union v4l2_ctrl_ptr p_def,
+ const union v4l2_ctrl_ptr p_min,
+ const union v4l2_ctrl_ptr p_max,
void *priv)
{
struct v4l2_ctrl *ctrl;
@@ -1634,6 +1719,14 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
handler_set_err(hdl, -ERANGE);
return NULL;
}
+
+ if ((!p_def.p_const && p_min.p_const) ||
+ (p_min.p_const && !p_max.p_const) ||
+ (!p_min.p_const && p_max.p_const)) {
+ handler_set_err(hdl, -EINVAL);
+ return NULL;
+ }
+
err = check_range(type, min, max, step, def);
if (err) {
handler_set_err(hdl, err);
@@ -1675,6 +1768,8 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,

if (type >= V4L2_CTRL_COMPOUND_TYPES && p_def.p_const)
sz_extra += elem_size;
+ if (type >= V4L2_CTRL_COMPOUND_TYPES && p_min.p_const)
+ sz_extra += elem_size * 2;

ctrl = kvzalloc(sizeof(*ctrl) + sz_extra, GFP_KERNEL);
if (ctrl == NULL) {
@@ -1740,6 +1835,14 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
memcpy(ctrl->p_def.p, p_def.p_const, elem_size);
}

+ if (type >= V4L2_CTRL_COMPOUND_TYPES &&
+ p_min.p_const && p_max.p_const) {
+ ctrl->p_min.p = ctrl->p_def.p + elem_size;
+ memcpy(ctrl->p_min.p, p_min.p_const, elem_size);
+ ctrl->p_max.p = ctrl->p_min.p + elem_size;
+ memcpy(ctrl->p_max.p, p_max.p_const, elem_size);
+ }
+
ctrl->type_ops->init(ctrl, 0, ctrl->p_cur);
cur_to_new(ctrl);

@@ -1790,7 +1893,8 @@ 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, cfg->p_def, priv);
+ flags, qmenu, qmenu_int, cfg->p_def, cfg->p_min,
+ cfg->p_max, priv);
if (ctrl)
ctrl->is_private = cfg->is_private;
return ctrl;
@@ -1815,7 +1919,8 @@ 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, ptr_null, NULL);
+ flags, NULL, NULL, ptr_null, ptr_null,
+ ptr_null, NULL);
}
EXPORT_SYMBOL(v4l2_ctrl_new_std);

@@ -1848,7 +1953,8 @@ 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, ptr_null, NULL);
+ flags, qmenu, qmenu_int, ptr_null, ptr_null,
+ ptr_null, NULL);
}
EXPORT_SYMBOL(v4l2_ctrl_new_std_menu);

@@ -1880,7 +1986,8 @@ 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, ptr_null, NULL);
+ flags, qmenu, NULL, ptr_null, ptr_null,
+ ptr_null, NULL);

}
EXPORT_SYMBOL(v4l2_ctrl_new_std_menu_items);
@@ -1888,7 +1995,9 @@ 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 union v4l2_ctrl_ptr p_def,
+ const union v4l2_ctrl_ptr p_min,
+ const union v4l2_ctrl_ptr p_max)
{
const char *name;
enum v4l2_ctrl_type type;
@@ -1902,7 +2011,7 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_compound(struct v4l2_ctrl_handler *hdl,
}
return v4l2_ctrl_new(hdl, ops, NULL, id, name, type,
min, max, step, def, NULL, 0,
- flags, NULL, NULL, p_def, NULL);
+ flags, NULL, NULL, p_def, p_min, p_max, NULL);
}
EXPORT_SYMBOL(v4l2_ctrl_new_std_compound);

@@ -1926,7 +2035,8 @@ 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, ptr_null, NULL);
+ flags, NULL, qmenu_int, ptr_null, ptr_null,
+ ptr_null, NULL);
}
EXPORT_SYMBOL(v4l2_ctrl_new_int_menu);

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index fddba75d9074..5d49e6d71b64 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -893,7 +893,9 @@ static bool check_ext_ctrls(struct v4l2_ext_controls *c, unsigned long ioctl)
return false;
break;
case V4L2_CTRL_WHICH_DEF_VAL:
- /* Default value cannot be changed */
+ case V4L2_CTRL_WHICH_MIN_VAL:
+ case V4L2_CTRL_WHICH_MAX_VAL:
+ /* Default, minimum or maximum value cannot be changed */
if (ioctl == VIDIOC_S_EXT_CTRLS ||
ioctl == VIDIOC_TRY_EXT_CTRLS) {
c->error_idx = c->count;
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 1846caf9dd53..6feeb18411e4 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -125,6 +125,8 @@ struct v4l2_ctrl_ops {
*
* @equal: return true if all ctrl->elems array elements are equal.
* @init: initialize the value for array elements from from_idx to ctrl->elems.
+ * @minimum: set the value to the minimum value of the control.
+ * @maximum: set the value to the maximum value of the control.
* @log: log the value.
* @validate: validate the value for ctrl->new_elems array elements.
* Return 0 on success and a negative value otherwise.
@@ -134,6 +136,10 @@ struct v4l2_ctrl_type_ops {
union v4l2_ctrl_ptr ptr1, union v4l2_ctrl_ptr ptr2);
void (*init)(const struct v4l2_ctrl *ctrl, u32 from_idx,
union v4l2_ctrl_ptr ptr);
+ int (*minimum)(const struct v4l2_ctrl *ctrl, u32 idx,
+ union v4l2_ctrl_ptr ptr);
+ int (*maximum)(const struct v4l2_ctrl *ctrl, u32 idx,
+ union v4l2_ctrl_ptr ptr);
void (*log)(const struct v4l2_ctrl *ctrl);
int (*validate)(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
};
@@ -239,6 +245,12 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv);
* @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_min: The control's minimum value represented via a union which
+ * provides a standard way of accessing control types
+ * through a pointer (for compound controls only).
+ * @p_max: The control's maximum 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.
@@ -298,6 +310,8 @@ struct v4l2_ctrl {
} cur;

union v4l2_ctrl_ptr p_def;
+ union v4l2_ctrl_ptr p_min;
+ union v4l2_ctrl_ptr p_max;
union v4l2_ctrl_ptr p_new;
union v4l2_ctrl_ptr p_cur;
};
@@ -417,6 +431,8 @@ struct v4l2_ctrl_handler {
* @step: The control's step value for non-menu controls.
* @def: The control's default value.
* @p_def: The control's default value for compound controls.
+ * @p_min: The control's minimum value for compound controls.
+ * @p_max: The control's maximum value for compound controls.
* @dims: The size of each dimension.
* @elem_size: The size in bytes of the control.
* @flags: The control's flags.
@@ -446,6 +462,8 @@ struct v4l2_ctrl_config {
u64 step;
s64 def;
union v4l2_ctrl_ptr p_def;
+ union v4l2_ctrl_ptr p_min;
+ union v4l2_ctrl_ptr p_max;
u32 dims[V4L2_CTRL_MAX_DIMS];
u32 elem_size;
u32 flags;
@@ -715,17 +733,23 @@ struct v4l2_ctrl *v4l2_ctrl_new_std_menu_items(struct v4l2_ctrl_handler *hdl,
* @ops: The control ops.
* @id: The control ID.
* @p_def: The control's default value.
+ * @p_min: The control's minimum value.
+ * @p_max: The control's maximum value.
*
- * Sames as v4l2_ctrl_new_std(), but with support to compound controls, thanks
- * to the @p_def field. Use v4l2_ctrl_ptr_create() to create @p_def from a
- * pointer. Use v4l2_ctrl_ptr_create(NULL) if the default value of the
- * compound control should be all zeroes.
+ * Same as v4l2_ctrl_new_std(), but with support to compound controls, thanks
+ * to the @p_def/min/max fields. Use v4l2_ctrl_ptr_create() to create
+ * @p_def/min/max from a pointer. Use v4l2_ctrl_ptr_create(NULL) if the
+ * default value of the compound control should be all zeroes. Use
+ * v4l2_ctrl_ptr_create(NULL) if the min/max value of the compound control
+ * is not defined, -ENODATA will be returned in this case.
*
*/
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 union v4l2_ctrl_ptr p_def,
+ const union v4l2_ctrl_ptr p_min,
+ const union v4l2_ctrl_ptr p_max);

/**
* v4l2_ctrl_new_int_menu() - Create a new standard V4L2 integer menu control.
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index a81951c51325..5f698b49c02e 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -1827,6 +1827,8 @@ struct v4l2_ext_controls {
#define V4L2_CTRL_WHICH_CUR_VAL 0
#define V4L2_CTRL_WHICH_DEF_VAL 0x0f000000
#define V4L2_CTRL_WHICH_REQUEST_VAL 0x0f010000
+#define V4L2_CTRL_WHICH_MIN_VAL 0x0f020000
+#define V4L2_CTRL_WHICH_MAX_VAL 0x0f030000

enum v4l2_ctrl_type {
V4L2_CTRL_TYPE_INTEGER = 1,
--
2.38.0.135.g90850a2211-goog