drivers/media/platform/vimc/vimc-capture.c

   1 /*
   2  * vimc-capture.c Virtual Media Controller Driver
   3  *
   4  * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 #include <linux/component.h>
  19 #include <linux/module.h>
  20 #include <linux/mod_devicetable.h>
  21 #include <linux/platform_device.h>
  22 #include <media/v4l2-ioctl.h>
  23 #include <media/videobuf2-core.h>
  24 #include <media/videobuf2-vmalloc.h>
  25
  26 #include "vimc-common.h"
  27
  28 #define VIMC_CAP_DRV_NAME "vimc-capture"
  29
  30 struct vimc_cap_device {
  31         struct vimc_ent_device ved;
  32         struct video_device vdev;
  33         struct device *dev;
  34         struct v4l2_pix_format format;
  35         struct vb2_queue queue;
  36         struct list_head buf_list;
  37         /*
  38          * NOTE: in a real driver, a spin lock must be used to access the
  39          * queue because the frames are generated from a hardware interruption
  40          * and the isr is not allowed to sleep.
  41          * Even if it is not necessary a spinlock in the vimc driver, we
  42          * use it here as a code reference
  43          */
  44         spinlock_t qlock;
  45         struct mutex lock;
  46         u32 sequence;
  47         struct media_pipeline pipe;
  48 };
  49
  50 static const struct v4l2_pix_format fmt_default = {
  51         .width = 640,
  52         .height = 480,
  53         .pixelformat = V4L2_PIX_FMT_RGB24,
  54         .field = V4L2_FIELD_NONE,
  55         .colorspace = V4L2_COLORSPACE_DEFAULT,
  56 };
  57
  58 struct vimc_cap_buffer {
  59         /*
  60          * struct vb2_v4l2_buffer must be the first element
  61          * the videobuf2 framework will allocate this struct based on
  62          * buf_struct_size and use the first sizeof(struct vb2_buffer) bytes of
  63          * memory as a vb2_buffer
  64          */
  65         struct vb2_v4l2_buffer vb2;
  66         struct list_head list;
  67 };
  68
  69 static int vimc_cap_querycap(struct file *file, void *priv,
  70                              struct v4l2_capability *cap)
  71 {
  72         struct vimc_cap_device *vcap = video_drvdata(file);
  73
  74         strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
  75         strlcpy(cap->card, KBUILD_MODNAME, sizeof(cap->card));
  76         snprintf(cap->bus_info, sizeof(cap->bus_info),
  77                  "platform:%s", vcap->vdev.v4l2_dev->name);
  78
  79         return 0;
  80 }
  81
  82 static void vimc_cap_get_format(struct vimc_ent_device *ved,
  83                                 struct v4l2_pix_format *fmt)
  84 {
  85         struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
  86                                                     ved);
  87
  88         *fmt = vcap->format;
  89 }
  90
  91 static int vimc_cap_g_fmt_vid_cap(struct file *file, void *priv,
  92                                   struct v4l2_format *f)
  93 {
  94         struct vimc_cap_device *vcap = video_drvdata(file);
  95
  96         f->fmt.pix = vcap->format;
  97
  98         return 0;
  99 }
 100
 101 static int vimc_cap_try_fmt_vid_cap(struct file *file, void *priv,
 102                                     struct v4l2_format *f)
 103 {
 104         struct v4l2_pix_format *format = &f->fmt.pix;
 105         const struct vimc_pix_map *vpix;
 106
 107         format->width = clamp_t(u32, format->width, VIMC_FRAME_MIN_WIDTH,
 108                                 VIMC_FRAME_MAX_WIDTH) & ~1;
 109         format->height = clamp_t(u32, format->height, VIMC_FRAME_MIN_HEIGHT,
 110                                  VIMC_FRAME_MAX_HEIGHT) & ~1;
 111
 112         /* Don't accept a pixelformat that is not on the table */
 113         vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
 114         if (!vpix) {
 115                 format->pixelformat = fmt_default.pixelformat;
 116                 vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
 117         }
 118         /* TODO: Add support for custom bytesperline values */
 119         format->bytesperline = format->width * vpix->bpp;
 120         format->sizeimage = format->bytesperline * format->height;
 121
 122         if (format->field == V4L2_FIELD_ANY)
 123                 format->field = fmt_default.field;
 124
 125         vimc_colorimetry_clamp(format);
 126
 127         return 0;
 128 }
 129
 130 static int vimc_cap_s_fmt_vid_cap(struct file *file, void *priv,
 131                                   struct v4l2_format *f)
 132 {
 133         struct vimc_cap_device *vcap = video_drvdata(file);
 134
 135         /* Do not change the format while stream is on */
 136         if (vb2_is_busy(&vcap->queue))
 137                 return -EBUSY;
 138
 139         vimc_cap_try_fmt_vid_cap(file, priv, f);
 140
 141         dev_dbg(vcap->dev, "%s: format update: "
 142                 "old:%dx%d (0x%x, %d, %d, %d, %d) "
 143                 "new:%dx%d (0x%x, %d, %d, %d, %d)\n", vcap->vdev.name,
 144                 /* old */
 145                 vcap->format.width, vcap->format.height,
 146                 vcap->format.pixelformat, vcap->format.colorspace,
 147                 vcap->format.quantization, vcap->format.xfer_func,
 148                 vcap->format.ycbcr_enc,
 149                 /* new */
 150                 f->fmt.pix.width, f->fmt.pix.height,
 151                 f->fmt.pix.pixelformat, f->fmt.pix.colorspace,
 152                 f->fmt.pix.quantization, f->fmt.pix.xfer_func,
 153                 f->fmt.pix.ycbcr_enc);
 154
 155         vcap->format = f->fmt.pix;
 156
 157         return 0;
 158 }
 159
 160 static int vimc_cap_enum_fmt_vid_cap(struct file *file, void *priv,
 161                                      struct v4l2_fmtdesc *f)
 162 {
 163         const struct vimc_pix_map *vpix = vimc_pix_map_by_index(f->index);
 164
 165         if (!vpix)
 166                 return -EINVAL;
 167
 168         f->pixelformat = vpix->pixelformat;
 169
 170         return 0;
 171 }
 172
 173 static int vimc_cap_enum_framesizes(struct file *file, void *fh,
 174                                     struct v4l2_frmsizeenum *fsize)
 175 {
 176         const struct vimc_pix_map *vpix;
 177
 178         if (fsize->index)
 179                 return -EINVAL;
 180
 181         /* Only accept code in the pix map table */
 182         vpix = vimc_pix_map_by_code(fsize->pixel_format);
 183         if (!vpix)
 184                 return -EINVAL;
 185
 186         fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
 187         fsize->stepwise.min_width = VIMC_FRAME_MIN_WIDTH;
 188         fsize->stepwise.max_width = VIMC_FRAME_MAX_WIDTH;
 189         fsize->stepwise.min_height = VIMC_FRAME_MIN_HEIGHT;
 190         fsize->stepwise.max_height = VIMC_FRAME_MAX_HEIGHT;
 191         fsize->stepwise.step_width = 2;
 192         fsize->stepwise.step_height = 2;
 193
 194         return 0;
 195 }
 196
 197 static const struct v4l2_file_operations vimc_cap_fops = {
 198         .owner          = THIS_MODULE,
 199         .open           = v4l2_fh_open,
 200         .release        = vb2_fop_release,
 201         .read           = vb2_fop_read,
 202         .poll           = vb2_fop_poll,
 203         .unlocked_ioctl = video_ioctl2,
 204         .mmap           = vb2_fop_mmap,
 205 };
 206
 207 static const struct v4l2_ioctl_ops vimc_cap_ioctl_ops = {
 208         .vidioc_querycap = vimc_cap_querycap,
 209
 210         .vidioc_g_fmt_vid_cap = vimc_cap_g_fmt_vid_cap,
 211         .vidioc_s_fmt_vid_cap = vimc_cap_s_fmt_vid_cap,
 212         .vidioc_try_fmt_vid_cap = vimc_cap_try_fmt_vid_cap,
 213         .vidioc_enum_fmt_vid_cap = vimc_cap_enum_fmt_vid_cap,
 214         .vidioc_enum_framesizes = vimc_cap_enum_framesizes,
 215
 216         .vidioc_reqbufs = vb2_ioctl_reqbufs,
 217         .vidioc_create_bufs = vb2_ioctl_create_bufs,
 218         .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
 219         .vidioc_querybuf = vb2_ioctl_querybuf,
 220         .vidioc_qbuf = vb2_ioctl_qbuf,
 221         .vidioc_dqbuf = vb2_ioctl_dqbuf,
 222         .vidioc_expbuf = vb2_ioctl_expbuf,
 223         .vidioc_streamon = vb2_ioctl_streamon,
 224         .vidioc_streamoff = vb2_ioctl_streamoff,
 225 };
 226
 227 static void vimc_cap_return_all_buffers(struct vimc_cap_device *vcap,
 228                                         enum vb2_buffer_state state)
 229 {
 230         struct vimc_cap_buffer *vbuf, *node;
 231
 232         spin_lock(&vcap->qlock);
 233
 234         list_for_each_entry_safe(vbuf, node, &vcap->buf_list, list) {
 235                 list_del(&vbuf->list);
 236                 vb2_buffer_done(&vbuf->vb2.vb2_buf, state);
 237         }
 238
 239         spin_unlock(&vcap->qlock);
 240 }
 241
 242 static int vimc_cap_start_streaming(struct vb2_queue *vq, unsigned int count)
 243 {
 244         struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
 245         struct media_entity *entity = &vcap->vdev.entity;
 246         int ret;
 247
 248         vcap->sequence = 0;
 249
 250         /* Start the media pipeline */
 251         ret = media_pipeline_start(entity, &vcap->pipe);
 252         if (ret) {
 253                 vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
 254                 return ret;
 255         }
 256
 257         /* Enable streaming from the pipe */
 258         ret = vimc_pipeline_s_stream(&vcap->vdev.entity, 1);
 259         if (ret) {
 260                 media_pipeline_stop(entity);
 261                 vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
 262                 return ret;
 263         }
 264
 265         return 0;
 266 }
 267
 268 /*
 269  * Stop the stream engine. Any remaining buffers in the stream queue are
 270  * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
 271  */
 272 static void vimc_cap_stop_streaming(struct vb2_queue *vq)
 273 {
 274         struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
 275
 276         /* Disable streaming from the pipe */
 277         vimc_pipeline_s_stream(&vcap->vdev.entity, 0);
 278
 279         /* Stop the media pipeline */
 280         media_pipeline_stop(&vcap->vdev.entity);
 281
 282         /* Release all active buffers */
 283         vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_ERROR);
 284 }
 285
 286 static void vimc_cap_buf_queue(struct vb2_buffer *vb2_buf)
 287 {
 288         struct vimc_cap_device *vcap = vb2_get_drv_priv(vb2_buf->vb2_queue);
 289         struct vimc_cap_buffer *buf = container_of(vb2_buf,
 290                                                    struct vimc_cap_buffer,
 291                                                    vb2.vb2_buf);
 292
 293         spin_lock(&vcap->qlock);
 294         list_add_tail(&buf->list, &vcap->buf_list);
 295         spin_unlock(&vcap->qlock);
 296 }
 297
 298 static int vimc_cap_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
 299                                 unsigned int *nplanes, unsigned int sizes[],
 300                                 struct device *alloc_devs[])
 301 {
 302         struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
 303
 304         if (*nplanes)
 305                 return sizes[0] < vcap->format.sizeimage ? -EINVAL : 0;
 306         /* We don't support multiplanes for now */
 307         *nplanes = 1;
 308         sizes[0] = vcap->format.sizeimage;
 309
 310         return 0;
 311 }
 312
 313 static int vimc_cap_buffer_prepare(struct vb2_buffer *vb)
 314 {
 315         struct vimc_cap_device *vcap = vb2_get_drv_priv(vb->vb2_queue);
 316         unsigned long size = vcap->format.sizeimage;
 317
 318         if (vb2_plane_size(vb, 0) < size) {
 319                 dev_err(vcap->dev, "%s: buffer too small (%lu < %lu)\n",
 320                         vcap->vdev.name, vb2_plane_size(vb, 0), size);
 321                 return -EINVAL;
 322         }
 323         return 0;
 324 }
 325
 326 static const struct vb2_ops vimc_cap_qops = {
 327         .start_streaming        = vimc_cap_start_streaming,
 328         .stop_streaming         = vimc_cap_stop_streaming,
 329         .buf_queue              = vimc_cap_buf_queue,
 330         .queue_setup            = vimc_cap_queue_setup,
 331         .buf_prepare            = vimc_cap_buffer_prepare,
 332         /*
 333          * Since q->lock is set we can use the standard
 334          * vb2_ops_wait_prepare/finish helper functions.
 335          */
 336         .wait_prepare           = vb2_ops_wait_prepare,
 337         .wait_finish            = vb2_ops_wait_finish,
 338 };
 339
 340 static const struct media_entity_operations vimc_cap_mops = {
 341         .link_validate          = vimc_link_validate,
 342 };
 343
 344 static void vimc_cap_comp_unbind(struct device *comp, struct device *master,
 345                                  void *master_data)
 346 {
 347         struct vimc_ent_device *ved = dev_get_drvdata(comp);
 348         struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
 349                                                     ved);
 350
 351         vb2_queue_release(&vcap->queue);
 352         media_entity_cleanup(ved->ent);
 353         video_unregister_device(&vcap->vdev);
 354         vimc_pads_cleanup(vcap->ved.pads);
 355         kfree(vcap);
 356 }
 357
 358 static void vimc_cap_process_frame(struct vimc_ent_device *ved,
 359                                    struct media_pad *sink, const void *frame)
 360 {
 361         struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
 362                                                     ved);
 363         struct vimc_cap_buffer *vimc_buf;
 364         void *vbuf;
 365
 366         spin_lock(&vcap->qlock);
 367
 368         /* Get the first entry of the list */
 369         vimc_buf = list_first_entry_or_null(&vcap->buf_list,
 370                                             typeof(*vimc_buf), list);
 371         if (!vimc_buf) {
 372                 spin_unlock(&vcap->qlock);
 373                 return;
 374         }
 375
 376         /* Remove this entry from the list */
 377         list_del(&vimc_buf->list);
 378
 379         spin_unlock(&vcap->qlock);
 380
 381         /* Fill the buffer */
 382         vimc_buf->vb2.vb2_buf.timestamp = ktime_get_ns();
 383         vimc_buf->vb2.sequence = vcap->sequence++;
 384         vimc_buf->vb2.field = vcap->format.field;
 385
 386         vbuf = vb2_plane_vaddr(&vimc_buf->vb2.vb2_buf, 0);
 387
 388         memcpy(vbuf, frame, vcap->format.sizeimage);
 389
 390         /* Set it as ready */
 391         vb2_set_plane_payload(&vimc_buf->vb2.vb2_buf, 0,
 392                               vcap->format.sizeimage);
 393         vb2_buffer_done(&vimc_buf->vb2.vb2_buf, VB2_BUF_STATE_DONE);
 394 }
 395
 396 static int vimc_cap_comp_bind(struct device *comp, struct device *master,
 397                               void *master_data)
 398 {
 399         struct v4l2_device *v4l2_dev = master_data;
 400         struct vimc_platform_data *pdata = comp->platform_data;
 401         const struct vimc_pix_map *vpix;
 402         struct vimc_cap_device *vcap;
 403         struct video_device *vdev;
 404         struct vb2_queue *q;
 405         int ret;
 406
 407         /* Allocate the vimc_cap_device struct */
 408         vcap = kzalloc(sizeof(*vcap), GFP_KERNEL);
 409         if (!vcap)
 410                 return -ENOMEM;
 411
 412         /* Allocate the pads */
 413         vcap->ved.pads =
 414                 vimc_pads_init(1, (const unsigned long[1]) {MEDIA_PAD_FL_SINK});
 415         if (IS_ERR(vcap->ved.pads)) {
 416                 ret = PTR_ERR(vcap->ved.pads);
 417                 goto err_free_vcap;
 418         }
 419
 420         /* Initialize the media entity */
 421         vcap->vdev.entity.name = pdata->entity_name;
 422         vcap->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
 423         ret = media_entity_pads_init(&vcap->vdev.entity,
 424                                      1, vcap->ved.pads);
 425         if (ret)
 426                 goto err_clean_pads;
 427
 428         /* Initialize the lock */
 429         mutex_init(&vcap->lock);
 430
 431         /* Initialize the vb2 queue */
 432         q = &vcap->queue;
 433         q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
 434         q->io_modes = VB2_MMAP | VB2_DMABUF;
 435         q->drv_priv = vcap;
 436         q->buf_struct_size = sizeof(struct vimc_cap_buffer);
 437         q->ops = &vimc_cap_qops;
 438         q->mem_ops = &vb2_vmalloc_memops;
 439         q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
 440         q->min_buffers_needed = 2;
 441         q->lock = &vcap->lock;
 442
 443         ret = vb2_queue_init(q);
 444         if (ret) {
 445                 dev_err(comp, "%s: vb2 queue init failed (err=%d)\n",
 446                         pdata->entity_name, ret);
 447                 goto err_clean_m_ent;
 448         }
 449
 450         /* Initialize buffer list and its lock */
 451         INIT_LIST_HEAD(&vcap->buf_list);
 452         spin_lock_init(&vcap->qlock);
 453
 454         /* Set default frame format */
 455         vcap->format = fmt_default;
 456         vpix = vimc_pix_map_by_pixelformat(vcap->format.pixelformat);
 457         vcap->format.bytesperline = vcap->format.width * vpix->bpp;
 458         vcap->format.sizeimage = vcap->format.bytesperline *
 459                                  vcap->format.height;
 460
 461         /* Fill the vimc_ent_device struct */
 462         vcap->ved.ent = &vcap->vdev.entity;
 463         vcap->ved.process_frame = vimc_cap_process_frame;
 464         vcap->ved.vdev_get_format = vimc_cap_get_format;
 465         dev_set_drvdata(comp, &vcap->ved);
 466         vcap->dev = comp;
 467
 468         /* Initialize the video_device struct */
 469         vdev = &vcap->vdev;
 470         vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
 471         vdev->entity.ops = &vimc_cap_mops;
 472         vdev->release = video_device_release_empty;
 473         vdev->fops = &vimc_cap_fops;
 474         vdev->ioctl_ops = &vimc_cap_ioctl_ops;
 475         vdev->lock = &vcap->lock;
 476         vdev->queue = q;
 477         vdev->v4l2_dev = v4l2_dev;
 478         vdev->vfl_dir = VFL_DIR_RX;
 479         strlcpy(vdev->name, pdata->entity_name, sizeof(vdev->name));
 480         video_set_drvdata(vdev, &vcap->ved);
 481
 482         /* Register the video_device with the v4l2 and the media framework */
 483         ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
 484         if (ret) {
 485                 dev_err(comp, "%s: video register failed (err=%d)\n",
 486                         vcap->vdev.name, ret);
 487                 goto err_release_queue;
 488         }
 489
 490         return 0;
 491
 492 err_release_queue:
 493         vb2_queue_release(q);
 494 err_clean_m_ent:
 495         media_entity_cleanup(&vcap->vdev.entity);
 496 err_clean_pads:
 497         vimc_pads_cleanup(vcap->ved.pads);
 498 err_free_vcap:
 499         kfree(vcap);
 500
 501         return ret;
 502 }
 503
 504 static const struct component_ops vimc_cap_comp_ops = {
 505         .bind = vimc_cap_comp_bind,
 506         .unbind = vimc_cap_comp_unbind,
 507 };
 508
 509 static int vimc_cap_probe(struct platform_device *pdev)
 510 {
 511         return component_add(&pdev->dev, &vimc_cap_comp_ops);
 512 }
 513
 514 static int vimc_cap_remove(struct platform_device *pdev)
 515 {
 516         component_del(&pdev->dev, &vimc_cap_comp_ops);
 517
 518         return 0;
 519 }
 520
 521 static const struct platform_device_id vimc_cap_driver_ids[] = {
 522         {
 523                 .name           = VIMC_CAP_DRV_NAME,
 524         },
 525         { }
 526 };
 527
 528 static struct platform_driver vimc_cap_pdrv = {
 529         .probe          = vimc_cap_probe,
 530         .remove         = vimc_cap_remove,
 531         .id_table       = vimc_cap_driver_ids,
 532         .driver         = {
 533                 .name   = VIMC_CAP_DRV_NAME,
 534         },
 535 };
 536
 537 module_platform_driver(vimc_cap_pdrv);
 538
 539 MODULE_DEVICE_TABLE(platform, vimc_cap_driver_ids);
 540
 541 MODULE_DESCRIPTION("Virtual Media Controller Driver (VIMC) Capture");
 542 MODULE_AUTHOR("Helen Mae Koike Fornazier <helen.fornazier@gmail.com>");
 543 MODULE_LICENSE("GPL");