From: Jing Leng <jleng@xxxxxxxxxxxxx>
Currently the uvc gadget can't support H264/HEVC transport, After
adding framebased stream support, the driver can support them.
Framebased stream is a little different from uncompressed stream.
So we can support framebased stream on the basis of uncompressed stream.
Here are the differences:
1. For the format, framebased format has an extra member (
__u8 bVariableSize) than uncompressed format.
2. For the frame, the layout of last three members of framebased frame
is different from uncompressed frame.
a. Last three members of uncompressed frame are:
u32 dw_max_video_frame_buffer_size;
u32 dw_default_frame_interval;
u8 b_frame_interval_type;
b. Last three members of framebased frame are:
u32 dw_default_frame_interval;
u8 b_frame_interval_type;
u32 dw_bytes_perline;
Here is an example of configuring H264:
cd /sys/kernel/config/usb_gadget/g1
ndir=functions/uvc.usb0/streaming/uncompressed/$NAME
mkdir -p $ndir
echo -n "H264" > $ndir/guidFormat # H264 or HEVC
echo 12 > $ndir/bBitsPerPixel
echo 1 > $ndir/bVariableSize
wdir=functions/uvc.usb0/streaming/uncompressed/$NAME/${HEIGHT}p
mkdir -p $wdir
echo 0 > $wdir/dwBytesPerLine
echo $WIDTH > $wdir/wWidth
echo $HEIGHT > $wdir/wHeight
echo 29491200 > $wdir/dwMinBitRate
echo 29491200 > $wdir/dwMaxBitRate
cat <<EOF > $wdir/dwFrameInterval
$INTERVAL
EOF
Signed-off-by: Jing Leng <jleng@xxxxxxxxxxxxx>
---
ChangeLog v2->v3:
- Revert modification in v2, use '#define' to handle frames.
- Update the example, the value of bBitsPerPixel is 12 for YUV420 encoded.
ChangeLog v1->v2:
- Use another way to handle frames, previous implementation within
- using union has a warning. (Reported-by: kernel test robot <lkp@xxxxxxxxx>)
---
.../ABI/testing/configfs-usb-gadget-uvc | 13 ++-
drivers/usb/gadget/function/uvc_configfs.c | 79 +++++++++++++++++--
drivers/usb/gadget/function/uvc_v4l2.c | 2 +
include/uapi/linux/usb/video.h | 3 +
4 files changed, 89 insertions(+), 8 deletions(-)
diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uvc b/Documentation/ABI/testing/configfs-usb-gadget-uvc
index 889ed45be4ca..2bf515dad516 100644
--- a/Documentation/ABI/testing/configfs-usb-gadget-uvc
+++ b/Documentation/ABI/testing/configfs-usb-gadget-uvc
@@ -243,7 +243,7 @@ Description: Uncompressed format descriptors
What: /config/usb-gadget/gadget/functions/uvc.name/streaming/uncompressed/name
Date: Dec 2014
KernelVersion: 4.0
-Description: Specific uncompressed format descriptors
+Description: Specific uncompressed/framebased format descriptors
================== =======================================
bFormatIndex unique id for this format descriptor;
@@ -264,12 +264,15 @@ Description: Specific uncompressed format descriptors
frame
guidFormat globally unique id used to identify
stream-encoding format
+ bVariableSize whether the data within the frame is of
+ variable length from frame to frame (
+ only for framebased format)
================== =======================================
What: /config/usb-gadget/gadget/functions/uvc.name/streaming/uncompressed/name/name
Date: Dec 2014
KernelVersion: 4.0
-Description: Specific uncompressed frame descriptors
+Description: Specific uncompressed/framebased frame descriptors
========================= =====================================
bFrameIndex unique id for this framedescriptor;
@@ -283,7 +286,11 @@ Description: Specific uncompressed frame descriptors
like to use as default
dwMaxVideoFrameBufferSize the maximum number of bytes the
compressor will produce for a video
- frame or still image
+ frame or still image (only for
+ uncompressed frame)
+ dwBytesPerLine the per-line bytes of the framebased
+ frame, e.g. H264 or HEVC (only for
+ framebased frame)
dwMaxBitRate the maximum bit rate at the shortest
frame interval in bps
dwMinBitRate the minimum bit rate at the longest
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index 77d64031aa9c..5dda825408ca 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -11,6 +11,7 @@
*/
#include <linux/sort.h>
+#include <linux/videodev2.h>
#include "u_uvc.h"
#include "uvc_configfs.h"
@@ -782,6 +783,8 @@ struct uvcg_format {
__u8 bmaControls[UVCG_STREAMING_CONTROL_SIZE];
};
+static u8 uvcg_uncompressed_subtype(struct uvcg_format *fmt);
+
static struct uvcg_format *to_uvcg_format(struct config_item *item)
{
return container_of(to_config_group(item), struct uvcg_format, group);
@@ -1072,9 +1075,23 @@ struct uvcg_frame {
u16 w_height;
u32 dw_min_bit_rate;
u32 dw_max_bit_rate;
+
+ /*
+ * The layout of last three members of framebased frame
+ * is different from uncompressed frame.
+ * Last three members of uncompressed frame are:
+ * u32 dw_max_video_frame_buffer_size;
+ * u32 dw_default_frame_interval;
+ * u8 b_frame_interval_type;
+ * Last three members of framebased frame are:
+ * u32 dw_default_frame_interval;
+ * u8 b_frame_interval_type;
+ * u32 dw_bytes_perline;
+ */
u32 dw_max_video_frame_buffer_size;
u32 dw_default_frame_interval;
u8 b_frame_interval_type;
+#define dw_bytes_perline dw_max_video_frame_buffer_size
} __attribute__((packed)) frame;
u32 *dw_frame_interval;
};
@@ -1186,6 +1203,18 @@ UVCG_FRAME_ATTR(dw_max_bit_rate, dwMaxBitRate, 32);
UVCG_FRAME_ATTR(dw_max_video_frame_buffer_size, dwMaxVideoFrameBufferSize, 32);
UVCG_FRAME_ATTR(dw_default_frame_interval, dwDefaultFrameInterval, 32);
+/*
+ * Set the alias of "dwMaxVideoFrameBufferSize" in uncompressed frame
+ * to "dwBytesPerLine" in framebased frame.
+ */
+static struct configfs_attribute uvcg_frame_attr_dw_bytes_perline = {
+ .ca_name = "dwBytesPerLine",
+ .ca_mode = 0666,
+ .ca_owner = THIS_MODULE,
+ .show = uvcg_frame_dw_max_video_frame_buffer_size_show,
+ .store = uvcg_frame_dw_max_video_frame_buffer_size_store,
+};
+
#undef UVCG_FRAME_ATTR
static ssize_t uvcg_frame_dw_frame_interval_show(struct config_item *item,
@@ -1329,6 +1358,7 @@ static struct configfs_attribute *uvcg_frame_attrs[] = {
&uvcg_frame_attr_dw_max_video_frame_buffer_size,
&uvcg_frame_attr_dw_default_frame_interval,
&uvcg_frame_attr_dw_frame_interval,
+ &uvcg_frame_attr_dw_bytes_perline,
NULL,
};
@@ -1365,7 +1395,12 @@ static struct config_item *uvcg_frame_make(struct config_group *group,
mutex_lock(&opts->lock);
fmt = to_uvcg_format(&group->cg_item);
if (fmt->type == UVCG_UNCOMPRESSED) {
- h->frame.b_descriptor_subtype = UVC_VS_FRAME_UNCOMPRESSED;
+ if (uvcg_uncompressed_subtype(fmt) == UVC_VS_FORMAT_UNCOMPRESSED) {
+ h->frame.b_descriptor_subtype = UVC_VS_FRAME_UNCOMPRESSED;
+ } else {
+ h->frame.b_descriptor_subtype = UVC_VS_FRAME_FRAME_BASED;
+ h->frame.dw_bytes_perline = 0;
+ }
h->fmt_type = UVCG_UNCOMPRESSED;
} else if (fmt->type == UVCG_MJPEG) {
h->frame.b_descriptor_subtype = UVC_VS_FRAME_MJPEG;
@@ -1425,6 +1460,14 @@ struct uvcg_uncompressed {
struct uvc_format_uncompressed desc;
};
+static u8 uvcg_uncompressed_subtype(struct uvcg_format *fmt)
+{
+ struct uvcg_uncompressed *ch = container_of(fmt,
+ struct uvcg_uncompressed, fmt);
+
+ return ch->desc.bDescriptorSubType;
+}
+
static struct uvcg_uncompressed *to_uvcg_uncompressed(struct config_item *item)
{
return container_of(
@@ -1466,6 +1509,7 @@ static ssize_t uvcg_uncompressed_guid_format_store(struct config_item *item,
struct f_uvc_opts *opts;
struct config_item *opts_item;
struct mutex *su_mutex = &ch->fmt.group.cg_subsys->su_mutex;
+ u32 fcc;
int ret;
mutex_lock(su_mutex); /* for navigating configfs hierarchy */
@@ -1481,7 +1525,17 @@ static ssize_t uvcg_uncompressed_guid_format_store(struct config_item *item,
memcpy(ch->desc.guidFormat, page,
min(sizeof(ch->desc.guidFormat), len));
- ret = sizeof(ch->desc.guidFormat);
+ ret = len;
+
+ fcc = v4l2_fourcc(ch->desc.guidFormat[0], ch->desc.guidFormat[1],
+ ch->desc.guidFormat[2], ch->desc.guidFormat[3]);
+ if (fcc == V4L2_PIX_FMT_H264 || fcc == V4L2_PIX_FMT_HEVC) {
+ ch->desc.bLength = UVC_DT_FORMAT_FRAMEBASED_SIZE;
+ ch->desc.bDescriptorSubType = UVC_VS_FORMAT_FRAME_BASED;
+ } else {
+ ch->desc.bLength = UVC_DT_FORMAT_UNCOMPRESSED_SIZE;
+ ch->desc.bDescriptorSubType = UVC_VS_FORMAT_UNCOMPRESSED;
+ }
end:
mutex_unlock(&opts->lock);
@@ -1581,6 +1635,7 @@ UVCG_UNCOMPRESSED_ATTR(b_default_frame_index, bDefaultFrameIndex, 8);
UVCG_UNCOMPRESSED_ATTR_RO(b_aspect_ratio_x, bAspectRatioX, 8);
UVCG_UNCOMPRESSED_ATTR_RO(b_aspect_ratio_y, bAspectRatioY, 8);
UVCG_UNCOMPRESSED_ATTR_RO(bm_interface_flags, bmInterfaceFlags, 8);
+UVCG_UNCOMPRESSED_ATTR(b_variable_size, bVariableSize, 8);
#undef UVCG_UNCOMPRESSED_ATTR
#undef UVCG_UNCOMPRESSED_ATTR_RO
@@ -1611,6 +1666,7 @@ static struct configfs_attribute *uvcg_uncompressed_attrs[] = {
&uvcg_uncompressed_attr_b_aspect_ratio_y,
&uvcg_uncompressed_attr_bm_interface_flags,
&uvcg_uncompressed_attr_bma_controls,
+ &uvcg_uncompressed_attr_b_variable_size,
NULL,
};
@@ -1644,6 +1700,7 @@ static struct config_group *uvcg_uncompressed_make(struct config_group *group,
h->desc.bAspectRatioY = 0;
h->desc.bmInterfaceFlags = 0;
h->desc.bCopyProtect = 0;
+ h->desc.bVariableSize = 0;
h->fmt.type = UVCG_UNCOMPRESSED;
config_group_init_type_name(&h->fmt.group, name,
@@ -2038,7 +2095,7 @@ static int __uvcg_cnt_strm(void *priv1, void *priv2, void *priv3, int n,
container_of(fmt, struct uvcg_uncompressed,
fmt);
- *size += sizeof(u->desc);
+ *size += u->desc.bLength;
} else if (fmt->type == UVCG_MJPEG) {
struct uvcg_mjpeg *m =
container_of(fmt, struct uvcg_mjpeg, fmt);
@@ -2108,8 +2165,8 @@ static int __uvcg_fill_strm(void *priv1, void *priv2, void *priv3, int n,
u->desc.bFormatIndex = n + 1;
u->desc.bNumFrameDescriptors = fmt->num_frames;
- memcpy(*dest, &u->desc, sizeof(u->desc));
- *dest += sizeof(u->desc);
+ memcpy(*dest, &u->desc, u->desc.bLength);
+ *dest += u->desc.bLength;
} else if (fmt->type == UVCG_MJPEG) {
struct uvcg_mjpeg *m =
container_of(fmt, struct uvcg_mjpeg, fmt);
@@ -2129,6 +2186,18 @@ static int __uvcg_fill_strm(void *priv1, void *priv2, void *priv3, int n,
sz = sizeof(frm->frame);
memcpy(*dest, &frm->frame, sz);
+ /*
+ * Reorder the frame struct layout due to the difference
+ * between uncompressed frame and framebased frame.
+ */
+ if (frm->frame.b_descriptor_subtype == UVC_VS_FRAME_FRAME_BASED) {
+ u8 *data = (u8 *)*dest;
+
+ memcpy(data + 17, &frm->frame.dw_default_frame_interval, 4);
+ memcpy(data + 21, &frm->frame.b_frame_interval_type, 1);
+ memcpy(data + 22, &frm->frame.dw_bytes_perline, 4);
+ }
+
*dest += sz;
sz = frm->frame.b_frame_interval_type *
sizeof(*frm->dw_frame_interval);
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c
index a2c78690c5c2..3d6217328c50 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -58,6 +58,8 @@ struct uvc_format {
static struct uvc_format uvc_formats[] = {
{ 16, V4L2_PIX_FMT_YUYV },
{ 0, V4L2_PIX_FMT_MJPEG },
+ { 0, V4L2_PIX_FMT_H264 },
+ { 0, V4L2_PIX_FMT_HEVC },
};
static int
diff --git a/include/uapi/linux/usb/video.h b/include/uapi/linux/usb/video.h
index bfdae12cdacf..383980bc9618 100644
--- a/include/uapi/linux/usb/video.h
+++ b/include/uapi/linux/usb/video.h
@@ -468,9 +468,12 @@ struct uvc_format_uncompressed {
__u8 bAspectRatioY;
__u8 bmInterfaceFlags;
__u8 bCopyProtect;
+ /* bVariableSize is only for framebased format. */
+ __u8 bVariableSize;
} __attribute__((__packed__));
#define UVC_DT_FORMAT_UNCOMPRESSED_SIZE 27
+#define UVC_DT_FORMAT_FRAMEBASED_SIZE 28
/* Uncompressed Payload - 3.1.2. Uncompressed Video Frame Descriptor */
struct uvc_frame_uncompressed {
--
2.17.1
