1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * uvc_metadata.c -- USB Video Class driver - Metadata handling 4 * 5 * Copyright (C) 2016 6 * Guennadi Liakhovetski (guennadi.liakhovetski@intel.com) 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/list.h> 11 #include <linux/module.h> 12 #include <linux/usb.h> 13 #include <linux/usb/uvc.h> 14 #include <linux/videodev2.h> 15 16 #include <media/v4l2-ioctl.h> 17 #include <media/videobuf2-v4l2.h> 18 #include <media/videobuf2-vmalloc.h> 19 20 #include "uvcvideo.h" 21 22 /* ----------------------------------------------------------------------------- 23 * V4L2 ioctls 24 */ 25 26 static int uvc_meta_v4l2_querycap(struct file *file, void *priv, 27 struct v4l2_capability *cap) 28 { 29 struct v4l2_fh *vfh = file_to_v4l2_fh(file); 30 struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); 31 struct uvc_video_chain *chain = stream->chain; 32 33 strscpy(cap->driver, "uvcvideo", sizeof(cap->driver)); 34 strscpy(cap->card, stream->dev->name, sizeof(cap->card)); 35 usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info)); 36 cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING 37 | chain->caps; 38 39 return 0; 40 } 41 42 static int uvc_meta_v4l2_get_format(struct file *file, void *priv, 43 struct v4l2_format *format) 44 { 45 struct v4l2_fh *vfh = file_to_v4l2_fh(file); 46 struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); 47 struct v4l2_meta_format *fmt = &format->fmt.meta; 48 49 if (format->type != vfh->vdev->queue->type) 50 return -EINVAL; 51 52 fmt->dataformat = stream->meta.format; 53 fmt->buffersize = UVC_METADATA_BUF_SIZE; 54 55 return 0; 56 } 57 58 static int uvc_meta_v4l2_try_format(struct file *file, void *priv, 59 struct v4l2_format *format) 60 { 61 struct v4l2_fh *vfh = file_to_v4l2_fh(file); 62 struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); 63 struct uvc_device *dev = stream->dev; 64 struct v4l2_meta_format *fmt = &format->fmt.meta; 65 u32 fmeta = V4L2_META_FMT_UVC; 66 67 if (format->type != vfh->vdev->queue->type) 68 return -EINVAL; 69 70 for (unsigned int i = 0; i < dev->nmeta_formats; i++) { 71 if (dev->meta_formats[i] == fmt->dataformat) { 72 fmeta = fmt->dataformat; 73 break; 74 } 75 } 76 77 memset(fmt, 0, sizeof(*fmt)); 78 79 fmt->dataformat = fmeta; 80 fmt->buffersize = UVC_METADATA_BUF_SIZE; 81 82 return 0; 83 } 84 85 static int uvc_meta_v4l2_set_format(struct file *file, void *priv, 86 struct v4l2_format *format) 87 { 88 struct v4l2_fh *vfh = file_to_v4l2_fh(file); 89 struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); 90 struct v4l2_meta_format *fmt = &format->fmt.meta; 91 int ret; 92 93 ret = uvc_meta_v4l2_try_format(file, priv, format); 94 if (ret < 0) 95 return ret; 96 97 /* 98 * We could in principle switch at any time, also during streaming. 99 * Metadata buffers would still be perfectly parseable, but it's more 100 * consistent and cleaner to disallow that. 101 */ 102 if (vb2_is_busy(&stream->meta.queue.queue)) 103 return -EBUSY; 104 105 stream->meta.format = fmt->dataformat; 106 107 return 0; 108 } 109 110 static int uvc_meta_v4l2_enum_formats(struct file *file, void *priv, 111 struct v4l2_fmtdesc *fdesc) 112 { 113 struct v4l2_fh *vfh = file_to_v4l2_fh(file); 114 struct uvc_streaming *stream = video_get_drvdata(vfh->vdev); 115 struct uvc_device *dev = stream->dev; 116 117 if (fdesc->type != vfh->vdev->queue->type) 118 return -EINVAL; 119 120 if (fdesc->index >= dev->nmeta_formats) 121 return -EINVAL; 122 123 fdesc->pixelformat = dev->meta_formats[fdesc->index]; 124 125 return 0; 126 } 127 128 static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = { 129 .vidioc_querycap = uvc_meta_v4l2_querycap, 130 .vidioc_g_fmt_meta_cap = uvc_meta_v4l2_get_format, 131 .vidioc_s_fmt_meta_cap = uvc_meta_v4l2_set_format, 132 .vidioc_try_fmt_meta_cap = uvc_meta_v4l2_try_format, 133 .vidioc_enum_fmt_meta_cap = uvc_meta_v4l2_enum_formats, 134 .vidioc_reqbufs = vb2_ioctl_reqbufs, 135 .vidioc_querybuf = vb2_ioctl_querybuf, 136 .vidioc_qbuf = vb2_ioctl_qbuf, 137 .vidioc_dqbuf = vb2_ioctl_dqbuf, 138 .vidioc_create_bufs = vb2_ioctl_create_bufs, 139 .vidioc_prepare_buf = vb2_ioctl_prepare_buf, 140 .vidioc_streamon = vb2_ioctl_streamon, 141 .vidioc_streamoff = vb2_ioctl_streamoff, 142 }; 143 144 /* ----------------------------------------------------------------------------- 145 * V4L2 File Operations 146 */ 147 148 static const struct v4l2_file_operations uvc_meta_fops = { 149 .owner = THIS_MODULE, 150 .unlocked_ioctl = video_ioctl2, 151 .open = v4l2_fh_open, 152 .release = vb2_fop_release, 153 .poll = vb2_fop_poll, 154 .mmap = vb2_fop_mmap, 155 }; 156 157 static struct uvc_entity *uvc_meta_find_msxu(struct uvc_device *dev) 158 { 159 static const u8 uvc_msxu_guid[16] = UVC_GUID_MSXU_1_5; 160 struct uvc_entity *entity; 161 162 list_for_each_entry(entity, &dev->entities, list) { 163 if (!memcmp(entity->guid, uvc_msxu_guid, sizeof(entity->guid))) 164 return entity; 165 } 166 167 return NULL; 168 } 169 170 static int uvc_meta_detect_msxu(struct uvc_device *dev) 171 { 172 u32 *data __free(kfree) = NULL; 173 struct uvc_entity *entity; 174 int ret; 175 176 entity = uvc_meta_find_msxu(dev); 177 if (!entity) 178 return 0; 179 180 /* 181 * USB requires buffers aligned in a special way, simplest way is to 182 * make sure that query_ctrl will work is to kmalloc() them. 183 */ 184 data = kmalloc(sizeof(*data), GFP_KERNEL); 185 if (!data) 186 return -ENOMEM; 187 188 /* 189 * Check if the metadata is already enabled, or if the device always 190 * returns metadata. 191 */ 192 ret = uvc_query_ctrl(dev, UVC_GET_CUR, entity->id, dev->intfnum, 193 UVC_MSXU_CONTROL_METADATA, data, sizeof(*data)); 194 if (ret) 195 return 0; 196 197 if (*data) { 198 dev->quirks |= UVC_QUIRK_MSXU_META; 199 return 0; 200 } 201 202 /* 203 * Set the value of UVC_MSXU_CONTROL_METADATA to the value reported by 204 * GET_MAX to enable production of MSXU metadata. The GET_MAX request 205 * reports the maximum size of the metadata, if its value is 0 then MSXU 206 * metadata is not supported. For more information, see 207 * https://learn.microsoft.com/en-us/windows-hardware/drivers/stream/uvc-extensions-1-5#2229-metadata-control 208 */ 209 ret = uvc_query_ctrl(dev, UVC_GET_MAX, entity->id, dev->intfnum, 210 UVC_MSXU_CONTROL_METADATA, data, sizeof(*data)); 211 if (ret || !*data) 212 return 0; 213 214 /* 215 * If we can set UVC_MSXU_CONTROL_METADATA, the device will report 216 * metadata. 217 */ 218 ret = uvc_query_ctrl(dev, UVC_SET_CUR, entity->id, dev->intfnum, 219 UVC_MSXU_CONTROL_METADATA, data, sizeof(*data)); 220 if (!ret) 221 dev->quirks |= UVC_QUIRK_MSXU_META; 222 223 return 0; 224 } 225 226 int uvc_meta_register(struct uvc_streaming *stream) 227 { 228 struct uvc_device *dev = stream->dev; 229 struct uvc_video_queue *queue = &stream->meta.queue; 230 231 stream->meta.format = V4L2_META_FMT_UVC; 232 233 return uvc_register_video_device(dev, stream, queue, 234 V4L2_BUF_TYPE_META_CAPTURE, 235 &uvc_meta_fops, &uvc_meta_ioctl_ops); 236 } 237 238 int uvc_meta_init(struct uvc_device *dev) 239 { 240 unsigned int i = 0; 241 int ret; 242 243 ret = uvc_meta_detect_msxu(dev); 244 if (ret) 245 return ret; 246 247 dev->meta_formats[i++] = V4L2_META_FMT_UVC; 248 249 if (dev->info->meta_format && 250 !WARN_ON(dev->info->meta_format == V4L2_META_FMT_UVC)) 251 dev->meta_formats[i++] = dev->info->meta_format; 252 253 if (dev->quirks & UVC_QUIRK_MSXU_META && 254 !WARN_ON(dev->info->meta_format == V4L2_META_FMT_UVC_MSXU_1_5)) 255 dev->meta_formats[i++] = V4L2_META_FMT_UVC_MSXU_1_5; 256 257 /* IMPORTANT: for new meta-formats update UVC_MAX_META_DATA_FORMATS. */ 258 dev->nmeta_formats = i; 259 260 return 0; 261 } 262