[PATCH v7 3/7] media: uvcvideo: Add support for compound controls

Yunke Cao
2022-06-28T07:57:46Z

Supports getting/setting current value.
Supports getting default value.
Handles V4L2_CTRL_FLAG_NEXT_COMPOUND.

Signed-off-by: Yunke Cao <yunkec@google.com>
---
drivers/media/usb/uvc/uvc_ctrl.c | 279 ++++++++++++++++++++++++++-----
drivers/media/usb/uvc/uvcvideo.h | 4 +
2 files changed, 238 insertions(+), 45 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 772d9d28a520..508ee04afbcd 100644
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -815,6 +815,34 @@ static void uvc_set_le_value(struct uvc_control_mapping *mapping,
}
}

+/* Extract the byte array specified by mapping->offset and mapping->size
+ * stored at 'data' to the output array 'data_out'.
+ */
+static int uvc_get_array(struct uvc_control_mapping *mapping, const u8 *data,
+ u8 *data_out)
+{
+ // Only supports byte-aligned data.
+ if (WARN_ON(mapping->offset % 8 || mapping->size % 8))
+ return -EINVAL;
+
+ memcpy(data_out, data + mapping->offset / 8, mapping->size / 8);
+ return 0;
+}
+
+/* Copy the byte array 'data_in' to the destination specified by mapping->offset
+ * and mapping->size stored at 'data'.
+ */
+static int uvc_set_array(struct uvc_control_mapping *mapping, const u8 *data_in,
+ u8 *data)
+{
+ // Only supports byte-aligned data.
+ if (WARN_ON(mapping->offset % 8 || mapping->size % 8))
+ return -EINVAL;
+
+ memcpy(data + mapping->offset / 8, data_in, mapping->size / 8);
+ return 0;
+}
+
/* ------------------------------------------------------------------------
* Terminal and unit management
*/
@@ -831,7 +859,7 @@ static int uvc_entity_match_guid(const struct uvc_entity *entity,

static void __uvc_find_control(struct uvc_entity *entity, u32 v4l2_id,
struct uvc_control_mapping **mapping, struct uvc_control **control,
- int next)
+ int next, int next_compound)
{
struct uvc_control *ctrl;
struct uvc_control_mapping *map;
@@ -846,14 +874,18 @@ static void __uvc_find_control(struct uvc_entity *entity, u32 v4l2_id,
continue;

list_for_each_entry(map, &ctrl->info.mappings, list) {
- if ((map->id == v4l2_id) && !next) {
+ if (map->id == v4l2_id && !next && !next_compound) {
*control = ctrl;
*mapping = map;
return;
}

if ((*mapping == NULL || (*mapping)->id > map->id) &&
- (map->id > v4l2_id) && next) {
+ (map->id > v4l2_id) &&
+ ((map->v4l2_type < V4L2_CTRL_COMPOUND_TYPES &&
+ next) ||
+ (map->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES &&
+ next_compound))) {
*control = ctrl;
*mapping = map;
}
@@ -867,6 +899,7 @@ static struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,
struct uvc_control *ctrl = NULL;
struct uvc_entity *entity;
int next = v4l2_id & V4L2_CTRL_FLAG_NEXT_CTRL;
+ int next_compound = v4l2_id & V4L2_CTRL_FLAG_NEXT_COMPOUND;

*mapping = NULL;

@@ -875,12 +908,13 @@ static struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,

/* Find the control. */
list_for_each_entry(entity, &chain->entities, chain) {
- __uvc_find_control(entity, v4l2_id, mapping, &ctrl, next);
- if (ctrl && !next)
+ __uvc_find_control(entity, v4l2_id, mapping, &ctrl, next,
+ next_compound);
+ if (ctrl && !next && !next_compound)
return ctrl;
}

- if (ctrl == NULL && !next)
+ if (!ctrl && !next && !next_compound)
uvc_dbg(chain->dev, CONTROL, "Control 0x%08x not found\n",
v4l2_id);

@@ -943,6 +977,39 @@ static int uvc_ctrl_populate_cache(struct uvc_video_chain *chain,
return 0;
}

+static int __uvc_ctrl_load_cur(struct uvc_video_chain *chain,
+ struct uvc_control *ctrl)
+{
+ int ret = 0;
+
+ if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
+ return -EACCES;
+
+ if (ctrl->loaded)
+ return 0;
+
+ if (ctrl->entity->get_cur) {
+ ret = ctrl->entity->get_cur(chain->dev,
+ ctrl->entity,
+ ctrl->info.selector,
+ uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+ ctrl->info.size);
+ } else {
+ ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
+ ctrl->entity->id, chain->dev->intfnum,
+ ctrl->info.selector,
+ uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+ ctrl->info.size);
+ }
+
+ if (ret < 0)
+ return ret;
+
+ ctrl->loaded = 1;
+
+ return ret;
+}
+
static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
const u8 *data)
{
@@ -963,35 +1030,19 @@ static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
return value;
}

-static int __uvc_ctrl_get(struct uvc_video_chain *chain,
- struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
- s32 *value)
+static int __uvc_ctrl_get_std(struct uvc_video_chain *chain,
+ struct uvc_control *ctrl,
+ struct uvc_control_mapping *mapping,
+ s32 *value)
{
int ret;

- if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
- return -EACCES;
-
- if (!ctrl->loaded) {
- if (ctrl->entity->get_cur) {
- ret = ctrl->entity->get_cur(chain->dev,
- ctrl->entity,
- ctrl->info.selector,
- uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
- ctrl->info.size);
- } else {
- ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
- ctrl->entity->id,
- chain->dev->intfnum,
- ctrl->info.selector,
- uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
- ctrl->info.size);
- }
- if (ret < 0)
- return ret;
+ if (mapping->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES)
+ return -EINVAL;

- ctrl->loaded = 1;
- }
+ ret = __uvc_ctrl_load_cur(chain, ctrl);
+ if (ret < 0)
+ return ret;

*value = __uvc_ctrl_get_value(mapping,
uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
@@ -999,6 +1050,57 @@ static int __uvc_ctrl_get(struct uvc_video_chain *chain,
return 0;
}

+static int __uvc_ctrl_get_compound_to_user(struct uvc_control_mapping *mapping,
+ struct uvc_control *ctrl,
+ int id,
+ struct v4l2_ext_control *xctrl)
+{
+ int ret, size;
+ u8 *data;
+
+ if (WARN_ON(!mapping->size % 8))
+ return -EINVAL;
+
+ size = mapping->size / 8;
+ if (xctrl->size < size) {
+ xctrl->size = size;
+ return -ENOSPC;
+ }
+
+ data = kmalloc(size, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = mapping->get_array(mapping, uvc_ctrl_data(ctrl, id), data);
+ if (ret < 0)
+ goto out;
+
+ ret = copy_to_user(xctrl->ptr, data, size) ? -EFAULT : 0;
+
+out:
+ kfree(data);
+ return ret;
+}
+
+static int __uvc_ctrl_get_compound(struct uvc_video_chain *chain,
+ struct uvc_control *ctrl,
+ struct uvc_control_mapping *mapping,
+ struct v4l2_ext_control *xctrl)
+{
+ int ret;
+
+ if (mapping->v4l2_type < V4L2_CTRL_COMPOUND_TYPES)
+ return -EINVAL;
+
+ ret = __uvc_ctrl_load_cur(chain, ctrl);
+ if (ret < 0)
+ return ret;
+
+ return __uvc_ctrl_get_compound_to_user(mapping, ctrl,
+ UVC_CTRL_DATA_CURRENT,
+ xctrl);
+}
+
static int __uvc_query_v4l2_class(struct uvc_video_chain *chain, u32 req_id,
u32 found_id)
{
@@ -1102,10 +1204,15 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,

if (mapping->master_id)
__uvc_find_control(ctrl->entity, mapping->master_id,
- &master_map, &master_ctrl, 0);
+ &master_map, &master_ctrl, 0, 0);
if (master_ctrl && (master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) {
- s32 val;
- int ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
+ int ret;
+ s32 val = 0;
+
+ if (master_map->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES)
+ return -EINVAL;
+
+ ret = __uvc_ctrl_get_std(chain, master_ctrl, master_map, &val);
if (ret < 0)
return ret;

@@ -1113,6 +1220,15 @@ static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
}

+ if (v4l2_ctrl->type >= V4L2_CTRL_COMPOUND_TYPES) {
+ v4l2_ctrl->flags |= V4L2_CTRL_FLAG_HAS_PAYLOAD;
+ v4l2_ctrl->default_value = 0;
+ v4l2_ctrl->minimum = 0;
+ v4l2_ctrl->maximum = 0;
+ v4l2_ctrl->step = 0;
+ return 0;
+ }
+
if (!ctrl->cached) {
int ret = uvc_ctrl_populate_cache(chain, ctrl);
if (ret < 0)
@@ -1346,11 +1462,12 @@ static void uvc_ctrl_send_slave_event(struct uvc_video_chain *chain,
u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
s32 val = 0;

- __uvc_find_control(master->entity, slave_id, &mapping, &ctrl, 0);
+ __uvc_find_control(master->entity, slave_id, &mapping, &ctrl, 0, 0);
if (ctrl == NULL)
return;

- if (__uvc_ctrl_get(chain, ctrl, mapping, &val) == 0)
+ if (mapping->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES ||
+ __uvc_ctrl_get_std(chain, ctrl, mapping, &val) == 0)
changes |= V4L2_EVENT_CTRL_CH_VALUE;

uvc_ctrl_send_event(chain, handle, ctrl, mapping, val, changes);
@@ -1517,7 +1634,8 @@ static int uvc_ctrl_add_event(struct v4l2_subscribed_event *sev, unsigned elems)
u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
s32 val = 0;

- if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
+ if (mapping->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES ||
+ __uvc_ctrl_get_std(handle->chain, ctrl, mapping, &val) == 0)
changes |= V4L2_EVENT_CTRL_CH_VALUE;

uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, val,
@@ -1647,7 +1765,7 @@ static int uvc_ctrl_find_ctrl_idx(struct uvc_entity *entity,

for (i = 0; i < ctrls->count; i++) {
__uvc_find_control(entity, ctrls->controls[i].id, &mapping,
- &ctrl_found, 0);
+ &ctrl_found, 0, 0);
if (uvc_control == ctrl_found)
return i;
}
@@ -1694,11 +1812,14 @@ int uvc_ctrl_get(struct uvc_video_chain *chain,
if (ctrl == NULL)
return -EINVAL;

- return __uvc_ctrl_get(chain, ctrl, mapping, &xctrl->value);
+ if (mapping->v4l2_type < V4L2_CTRL_COMPOUND_TYPES)
+ return __uvc_ctrl_get_std(chain, ctrl, mapping, &xctrl->value);
+ else
+ return __uvc_ctrl_get_compound(chain, ctrl, mapping, xctrl);
}

-int uvc_ctrl_get_fixed(struct uvc_video_chain *chain,
- struct v4l2_ext_control *xctrl)
+int __uvc_ctrl_get_fixed_std(struct uvc_video_chain *chain,
+ struct v4l2_ext_control *xctrl)
{
struct v4l2_queryctrl qc = { .id = xctrl->id };
int ret = uvc_query_v4l2_ctrl(chain, &qc);
@@ -1710,6 +1831,56 @@ int uvc_ctrl_get_fixed(struct uvc_video_chain *chain,
return 0;
}

+int uvc_ctrl_get_fixed(struct uvc_video_chain *chain,
+ struct v4l2_ext_control *xctrl)
+{
+ struct uvc_control *ctrl;
+ struct uvc_control_mapping *mapping;
+ int ret;
+
+ if (__uvc_query_v4l2_class(chain, xctrl->id, 0) >= 0)
+ return -EACCES;
+
+ ctrl = uvc_find_control(chain, xctrl->id, &mapping);
+ if (!ctrl)
+ return -EINVAL;
+
+ if (mapping->v4l2_type < V4L2_CTRL_COMPOUND_TYPES)
+ return __uvc_ctrl_get_fixed_std(chain, xctrl);
+
+ if (!ctrl->cached) {
+ ret = uvc_ctrl_populate_cache(chain, ctrl);
+ if (ret < 0)
+ return ret;
+ }
+
+ return __uvc_ctrl_get_compound_to_user(mapping, ctrl, UVC_CTRL_DATA_DEF,
+ xctrl);
+}
+
+int __uvc_ctrl_set_compound(struct uvc_control_mapping *mapping,
+ struct v4l2_ext_control *xctrl,
+ struct uvc_control *ctrl)
+{
+ int ret;
+ u8 *data;
+
+ data = kmalloc(xctrl->size, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ ret = copy_from_user(data, xctrl->ptr, xctrl->size);
+ if (ret < 0)
+ goto out;
+
+ ret = mapping->set_array(mapping, data,
+ uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+
+out:
+ kfree(data);
+ return ret;
+}
+
int uvc_ctrl_set(struct uvc_fh *handle,
struct v4l2_ext_control *xctrl)
{
@@ -1820,8 +1991,14 @@ int uvc_ctrl_set(struct uvc_fh *handle,
ctrl->info.size);
}

- mapping->set(mapping, value,
- uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+ if (mapping->v4l2_type < V4L2_CTRL_COMPOUND_TYPES) {
+ mapping->set(mapping, value,
+ uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+ } else {
+ ret = __uvc_ctrl_set_compound(mapping, xctrl, ctrl);
+ if (ret < 0)
+ return ret;
+ }

if (ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
ctrl->handle = handle;
@@ -2220,10 +2397,14 @@ static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
return -ENOMEM;
}

- if (map->get == NULL)
+ if (!map->get && map->v4l2_type < V4L2_CTRL_COMPOUND_TYPES)
map->get = uvc_get_le_value;
- if (map->set == NULL)
+ if (!map->set && map->v4l2_type < V4L2_CTRL_COMPOUND_TYPES)
map->set = uvc_set_le_value;
+ if (!map->get_array && map->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES)
+ map->get_array = uvc_get_array;
+ if (!map->set_array && map->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES)
+ map->set_array = uvc_set_array;

for (i = 0; i < ARRAY_SIZE(uvc_control_classes); i++) {
if (V4L2_CTRL_ID2WHICH(uvc_control_classes[i]) ==
@@ -2233,6 +2414,14 @@ static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
}
}

+ if (map->v4l2_type < V4L2_CTRL_COMPOUND_TYPES &&
+ WARN_ON(!map->get || !map->set))
+ return -EINVAL;
+
+ if (map->v4l2_type >= V4L2_CTRL_COMPOUND_TYPES &&
+ WARN_ON(!map->get_array || !map->set_array))
+ return -EINVAL;
+
list_add_tail(&map->list, &ctrl->info.mappings);
uvc_dbg(chain->dev, CONTROL, "Adding mapping '%s' to control %pUl/%u\n",
uvc_map_get_name(map), ctrl->info.entity,
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index ba028ba7c34e..2f9b75faae83 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -262,8 +262,12 @@ struct uvc_control_mapping {

s32 (*get)(struct uvc_control_mapping *mapping, u8 query,
const u8 *data);
+ int (*get_array)(struct uvc_control_mapping *mapping, const u8 *data,
+ u8 *data_out);
void (*set)(struct uvc_control_mapping *mapping, s32 value,
u8 *data);
+ int (*set_array)(struct uvc_control_mapping *mapping, const u8 *data_in,
+ u8 *data);
};

struct uvc_control {
--
2.37.0.rc0.161.g10f37bed90-goog