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