]>
Commit | Line | Data |
---|---|---|
cdda479f LP |
1 | /* |
2 | * uvc_queue.c -- USB Video Class driver - Buffers management | |
3 | * | |
4 | * Copyright (C) 2005-2010 | |
5 | * Laurent Pinchart (laurent.pinchart@ideasonboard.com) | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
cdda479f LP |
11 | */ |
12 | ||
d6925225 | 13 | #include <linux/atomic.h> |
cdda479f LP |
14 | #include <linux/kernel.h> |
15 | #include <linux/mm.h> | |
16 | #include <linux/list.h> | |
17 | #include <linux/module.h> | |
18 | #include <linux/usb.h> | |
19 | #include <linux/videodev2.h> | |
20 | #include <linux/vmalloc.h> | |
21 | #include <linux/wait.h> | |
d6925225 | 22 | |
16bf900f | 23 | #include <media/v4l2-common.h> |
d6925225 | 24 | #include <media/videobuf2-vmalloc.h> |
cdda479f LP |
25 | |
26 | #include "uvc.h" | |
27 | ||
28 | /* ------------------------------------------------------------------------ | |
29 | * Video buffers queue management. | |
30 | * | |
31 | * Video queues is initialized by uvc_queue_init(). The function performs | |
32 | * basic initialization of the uvc_video_queue struct and never fails. | |
33 | * | |
d6925225 BS |
34 | * Video buffers are managed by videobuf2. The driver uses a mutex to protect |
35 | * the videobuf2 queue operations by serializing calls to videobuf2 and a | |
36 | * spinlock to protect the IRQ queue that holds the buffers to be processed by | |
37 | * the driver. | |
cdda479f LP |
38 | */ |
39 | ||
d6925225 BS |
40 | /* ----------------------------------------------------------------------------- |
41 | * videobuf2 queue operations | |
5d9955f8 | 42 | */ |
d6925225 BS |
43 | |
44 | static int uvc_queue_setup(struct vb2_queue *vq, const struct v4l2_format *fmt, | |
45 | unsigned int *nbuffers, unsigned int *nplanes, | |
46 | unsigned int sizes[], void *alloc_ctxs[]) | |
5d9955f8 | 47 | { |
d6925225 BS |
48 | struct uvc_video_queue *queue = vb2_get_drv_priv(vq); |
49 | struct uvc_video *video = container_of(queue, struct uvc_video, queue); | |
5d9955f8 | 50 | |
d6925225 BS |
51 | if (*nbuffers > UVC_MAX_VIDEO_BUFFERS) |
52 | *nbuffers = UVC_MAX_VIDEO_BUFFERS; | |
5d9955f8 | 53 | |
d6925225 BS |
54 | *nplanes = 1; |
55 | ||
56 | sizes[0] = video->imagesize; | |
5d9955f8 LP |
57 | |
58 | return 0; | |
59 | } | |
60 | ||
d6925225 | 61 | static int uvc_buffer_prepare(struct vb2_buffer *vb) |
cdda479f | 62 | { |
d6925225 BS |
63 | struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); |
64 | struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); | |
cdda479f | 65 | |
d6925225 BS |
66 | if (vb->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_OUTPUT && |
67 | vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) { | |
68 | uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n"); | |
69 | return -EINVAL; | |
70 | } | |
cdda479f | 71 | |
d6925225 BS |
72 | if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED)) |
73 | return -ENODEV; | |
cdda479f | 74 | |
d6925225 BS |
75 | buf->state = UVC_BUF_STATE_QUEUED; |
76 | buf->mem = vb2_plane_vaddr(vb, 0); | |
77 | buf->length = vb2_plane_size(vb, 0); | |
78 | if (vb->v4l2_buf.type == V4L2_BUF_TYPE_VIDEO_CAPTURE) | |
79 | buf->bytesused = 0; | |
80 | else | |
81 | buf->bytesused = vb2_get_plane_payload(vb, 0); | |
cdda479f | 82 | |
d6925225 BS |
83 | return 0; |
84 | } | |
cdda479f | 85 | |
d6925225 BS |
86 | static void uvc_buffer_queue(struct vb2_buffer *vb) |
87 | { | |
88 | struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); | |
89 | struct uvc_buffer *buf = container_of(vb, struct uvc_buffer, buf); | |
90 | unsigned long flags; | |
cdda479f | 91 | |
d6925225 | 92 | spin_lock_irqsave(&queue->irqlock, flags); |
cdda479f | 93 | |
d6925225 BS |
94 | if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) { |
95 | list_add_tail(&buf->queue, &queue->irqqueue); | |
96 | } else { | |
97 | /* If the device is disconnected return the buffer to userspace | |
98 | * directly. The next QBUF call will fail with -ENODEV. | |
99 | */ | |
100 | buf->state = UVC_BUF_STATE_ERROR; | |
101 | vb2_buffer_done(&buf->buf, VB2_BUF_STATE_ERROR); | |
cdda479f LP |
102 | } |
103 | ||
d6925225 | 104 | spin_unlock_irqrestore(&queue->irqlock, flags); |
cdda479f LP |
105 | } |
106 | ||
a2cc81d3 MG |
107 | static void uvc_wait_prepare(struct vb2_queue *vq) |
108 | { | |
109 | struct uvc_video_queue *queue = vb2_get_drv_priv(vq); | |
110 | ||
111 | mutex_unlock(&queue->mutex); | |
112 | } | |
113 | ||
114 | static void uvc_wait_finish(struct vb2_queue *vq) | |
115 | { | |
116 | struct uvc_video_queue *queue = vb2_get_drv_priv(vq); | |
117 | ||
118 | mutex_lock(&queue->mutex); | |
119 | } | |
120 | ||
d6925225 BS |
121 | static struct vb2_ops uvc_queue_qops = { |
122 | .queue_setup = uvc_queue_setup, | |
123 | .buf_prepare = uvc_buffer_prepare, | |
124 | .buf_queue = uvc_buffer_queue, | |
a2cc81d3 MG |
125 | .wait_prepare = uvc_wait_prepare, |
126 | .wait_finish = uvc_wait_finish, | |
d6925225 | 127 | }; |
cdda479f | 128 | |
d6925225 BS |
129 | static int uvc_queue_init(struct uvc_video_queue *queue, |
130 | enum v4l2_buf_type type) | |
cdda479f | 131 | { |
d6925225 | 132 | int ret; |
cdda479f | 133 | |
d6925225 BS |
134 | queue->queue.type = type; |
135 | queue->queue.io_modes = VB2_MMAP | VB2_USERPTR; | |
136 | queue->queue.drv_priv = queue; | |
137 | queue->queue.buf_struct_size = sizeof(struct uvc_buffer); | |
138 | queue->queue.ops = &uvc_queue_qops; | |
139 | queue->queue.mem_ops = &vb2_vmalloc_memops; | |
140 | ret = vb2_queue_init(&queue->queue); | |
141 | if (ret) | |
142 | return ret; | |
143 | ||
144 | mutex_init(&queue->mutex); | |
145 | spin_lock_init(&queue->irqlock); | |
146 | INIT_LIST_HEAD(&queue->irqqueue); | |
147 | queue->flags = 0; | |
cdda479f | 148 | |
d6925225 BS |
149 | return 0; |
150 | } | |
cdda479f | 151 | |
d6925225 BS |
152 | /* |
153 | * Free the video buffers. | |
154 | */ | |
155 | static void uvc_free_buffers(struct uvc_video_queue *queue) | |
156 | { | |
157 | mutex_lock(&queue->mutex); | |
158 | vb2_queue_release(&queue->queue); | |
cdda479f | 159 | mutex_unlock(&queue->mutex); |
cdda479f LP |
160 | } |
161 | ||
162 | /* | |
d6925225 | 163 | * Allocate the video buffers. |
cdda479f | 164 | */ |
d6925225 BS |
165 | static int uvc_alloc_buffers(struct uvc_video_queue *queue, |
166 | struct v4l2_requestbuffers *rb) | |
cdda479f | 167 | { |
d6925225 | 168 | int ret; |
cdda479f | 169 | |
d6925225 BS |
170 | mutex_lock(&queue->mutex); |
171 | ret = vb2_reqbufs(&queue->queue, rb); | |
172 | mutex_unlock(&queue->mutex); | |
cdda479f | 173 | |
d6925225 BS |
174 | return ret ? ret : rb->count; |
175 | } | |
cdda479f | 176 | |
d6925225 BS |
177 | static int uvc_query_buffer(struct uvc_video_queue *queue, |
178 | struct v4l2_buffer *buf) | |
179 | { | |
180 | int ret; | |
cdda479f | 181 | |
d6925225 BS |
182 | mutex_lock(&queue->mutex); |
183 | ret = vb2_querybuf(&queue->queue, buf); | |
184 | mutex_unlock(&queue->mutex); | |
cdda479f | 185 | |
d6925225 BS |
186 | return ret; |
187 | } | |
cdda479f | 188 | |
d6925225 BS |
189 | static int uvc_queue_buffer(struct uvc_video_queue *queue, |
190 | struct v4l2_buffer *buf) | |
191 | { | |
192 | unsigned long flags; | |
193 | int ret; | |
cdda479f | 194 | |
d6925225 BS |
195 | mutex_lock(&queue->mutex); |
196 | ret = vb2_qbuf(&queue->queue, buf); | |
ebe864a6 LP |
197 | if (ret < 0) |
198 | goto done; | |
199 | ||
cdda479f | 200 | spin_lock_irqsave(&queue->irqlock, flags); |
cdda479f LP |
201 | ret = (queue->flags & UVC_QUEUE_PAUSED) != 0; |
202 | queue->flags &= ~UVC_QUEUE_PAUSED; | |
cdda479f | 203 | spin_unlock_irqrestore(&queue->irqlock, flags); |
cdda479f | 204 | |
ebe864a6 LP |
205 | done: |
206 | mutex_unlock(&queue->mutex); | |
d6925225 | 207 | return ret; |
cdda479f LP |
208 | } |
209 | ||
210 | /* | |
211 | * Dequeue a video buffer. If nonblocking is false, block until a buffer is | |
212 | * available. | |
213 | */ | |
d6925225 BS |
214 | static int uvc_dequeue_buffer(struct uvc_video_queue *queue, |
215 | struct v4l2_buffer *buf, int nonblocking) | |
cdda479f | 216 | { |
d6925225 | 217 | int ret; |
cdda479f LP |
218 | |
219 | mutex_lock(&queue->mutex); | |
d6925225 | 220 | ret = vb2_dqbuf(&queue->queue, buf, nonblocking); |
cdda479f | 221 | mutex_unlock(&queue->mutex); |
d6925225 | 222 | |
cdda479f LP |
223 | return ret; |
224 | } | |
225 | ||
226 | /* | |
227 | * Poll the video queue. | |
228 | * | |
229 | * This function implements video queue polling and is intended to be used by | |
230 | * the device poll handler. | |
231 | */ | |
d6925225 BS |
232 | static unsigned int uvc_queue_poll(struct uvc_video_queue *queue, |
233 | struct file *file, poll_table *wait) | |
cdda479f | 234 | { |
d6925225 | 235 | unsigned int ret; |
cdda479f LP |
236 | |
237 | mutex_lock(&queue->mutex); | |
d6925225 | 238 | ret = vb2_poll(&queue->queue, file, wait); |
cdda479f | 239 | mutex_unlock(&queue->mutex); |
cdda479f | 240 | |
d6925225 | 241 | return ret; |
cdda479f LP |
242 | } |
243 | ||
d6925225 BS |
244 | static int uvc_queue_mmap(struct uvc_video_queue *queue, |
245 | struct vm_area_struct *vma) | |
cdda479f | 246 | { |
d6925225 | 247 | int ret; |
cdda479f LP |
248 | |
249 | mutex_lock(&queue->mutex); | |
d6925225 | 250 | ret = vb2_mmap(&queue->queue, vma); |
cdda479f | 251 | mutex_unlock(&queue->mutex); |
d6925225 | 252 | |
cdda479f LP |
253 | return ret; |
254 | } | |
255 | ||
2f1d5706 BS |
256 | #ifndef CONFIG_MMU |
257 | /* | |
258 | * Get unmapped area. | |
259 | * | |
260 | * NO-MMU arch need this function to make mmap() work correctly. | |
261 | */ | |
262 | static unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue, | |
263 | unsigned long pgoff) | |
264 | { | |
265 | unsigned long ret; | |
266 | ||
267 | mutex_lock(&queue->mutex); | |
268 | ret = vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0); | |
269 | mutex_unlock(&queue->mutex); | |
270 | return ret; | |
271 | } | |
272 | #endif | |
273 | ||
5d9955f8 LP |
274 | /* |
275 | * Cancel the video buffers queue. | |
276 | * | |
277 | * Cancelling the queue marks all buffers on the irq queue as erroneous, | |
278 | * wakes them up and removes them from the queue. | |
279 | * | |
280 | * If the disconnect parameter is set, further calls to uvc_queue_buffer will | |
281 | * fail with -ENODEV. | |
282 | * | |
283 | * This function acquires the irq spinlock and can be called from interrupt | |
284 | * context. | |
285 | */ | |
286 | static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) | |
287 | { | |
288 | struct uvc_buffer *buf; | |
289 | unsigned long flags; | |
290 | ||
291 | spin_lock_irqsave(&queue->irqlock, flags); | |
292 | while (!list_empty(&queue->irqqueue)) { | |
293 | buf = list_first_entry(&queue->irqqueue, struct uvc_buffer, | |
294 | queue); | |
295 | list_del(&buf->queue); | |
296 | buf->state = UVC_BUF_STATE_ERROR; | |
d6925225 | 297 | vb2_buffer_done(&buf->buf, VB2_BUF_STATE_ERROR); |
5d9955f8 LP |
298 | } |
299 | /* This must be protected by the irqlock spinlock to avoid race | |
300 | * conditions between uvc_queue_buffer and the disconnection event that | |
301 | * could result in an interruptible wait in uvc_dequeue_buffer. Do not | |
302 | * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED | |
303 | * state outside the queue code. | |
304 | */ | |
305 | if (disconnect) | |
306 | queue->flags |= UVC_QUEUE_DISCONNECTED; | |
307 | spin_unlock_irqrestore(&queue->irqlock, flags); | |
308 | } | |
309 | ||
cdda479f LP |
310 | /* |
311 | * Enable or disable the video buffers queue. | |
312 | * | |
313 | * The queue must be enabled before starting video acquisition and must be | |
314 | * disabled after stopping it. This ensures that the video buffers queue | |
315 | * state can be properly initialized before buffers are accessed from the | |
316 | * interrupt handler. | |
317 | * | |
318 | * Enabling the video queue initializes parameters (such as sequence number, | |
319 | * sync pattern, ...). If the queue is already enabled, return -EBUSY. | |
320 | * | |
321 | * Disabling the video queue cancels the queue and removes all buffers from | |
322 | * the main queue. | |
323 | * | |
324 | * This function can't be called from interrupt context. Use | |
325 | * uvc_queue_cancel() instead. | |
326 | */ | |
5d9955f8 | 327 | static int uvc_queue_enable(struct uvc_video_queue *queue, int enable) |
cdda479f | 328 | { |
d6925225 | 329 | unsigned long flags; |
cdda479f LP |
330 | int ret = 0; |
331 | ||
332 | mutex_lock(&queue->mutex); | |
333 | if (enable) { | |
d6925225 BS |
334 | ret = vb2_streamon(&queue->queue, queue->queue.type); |
335 | if (ret < 0) | |
cdda479f | 336 | goto done; |
d6925225 | 337 | |
cdda479f | 338 | queue->sequence = 0; |
cdda479f LP |
339 | queue->buf_used = 0; |
340 | } else { | |
d6925225 BS |
341 | ret = vb2_streamoff(&queue->queue, queue->queue.type); |
342 | if (ret < 0) | |
343 | goto done; | |
cdda479f | 344 | |
d6925225 BS |
345 | spin_lock_irqsave(&queue->irqlock, flags); |
346 | INIT_LIST_HEAD(&queue->irqqueue); | |
cdda479f | 347 | |
d6925225 BS |
348 | /* |
349 | * FIXME: We need to clear the DISCONNECTED flag to ensure that | |
350 | * applications will be able to queue buffers for the next | |
351 | * streaming run. However, clearing it here doesn't guarantee | |
352 | * that the device will be reconnected in the meantime. | |
353 | */ | |
354 | queue->flags &= ~UVC_QUEUE_DISCONNECTED; | |
355 | spin_unlock_irqrestore(&queue->irqlock, flags); | |
cdda479f LP |
356 | } |
357 | ||
358 | done: | |
359 | mutex_unlock(&queue->mutex); | |
360 | return ret; | |
361 | } | |
362 | ||
95faf82b | 363 | /* called with &queue_irqlock held.. */ |
d6925225 BS |
364 | static struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, |
365 | struct uvc_buffer *buf) | |
cdda479f LP |
366 | { |
367 | struct uvc_buffer *nextbuf; | |
cdda479f LP |
368 | |
369 | if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) && | |
d6925225 | 370 | buf->length != buf->bytesused) { |
cdda479f | 371 | buf->state = UVC_BUF_STATE_QUEUED; |
d6925225 | 372 | vb2_set_plane_payload(&buf->buf, 0, 0); |
cdda479f LP |
373 | return buf; |
374 | } | |
375 | ||
cdda479f LP |
376 | list_del(&buf->queue); |
377 | if (!list_empty(&queue->irqqueue)) | |
378 | nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, | |
379 | queue); | |
380 | else | |
381 | nextbuf = NULL; | |
cdda479f | 382 | |
f17388cc | 383 | buf->buf.v4l2_buf.field = V4L2_FIELD_NONE; |
d6925225 | 384 | buf->buf.v4l2_buf.sequence = queue->sequence++; |
16bf900f | 385 | v4l2_get_timestamp(&buf->buf.v4l2_buf.timestamp); |
d6925225 BS |
386 | |
387 | vb2_set_plane_payload(&buf->buf, 0, buf->bytesused); | |
388 | vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE); | |
cdda479f | 389 | |
cdda479f LP |
390 | return nextbuf; |
391 | } | |
392 | ||
5d9955f8 | 393 | static struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue) |
cdda479f LP |
394 | { |
395 | struct uvc_buffer *buf = NULL; | |
396 | ||
397 | if (!list_empty(&queue->irqqueue)) | |
398 | buf = list_first_entry(&queue->irqqueue, struct uvc_buffer, | |
399 | queue); | |
400 | else | |
401 | queue->flags |= UVC_QUEUE_PAUSED; | |
402 | ||
403 | return buf; | |
404 | } | |
405 |