Loading...
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * uvc_queue.c -- USB Video Class driver - Buffers management
4 *
5 * Copyright (C) 2005-2010
6 * Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7 */
8
9#include <linux/atomic.h>
10#include <linux/kernel.h>
11#include <linux/mm.h>
12#include <linux/list.h>
13#include <linux/module.h>
14#include <linux/usb.h>
15#include <linux/videodev2.h>
16#include <linux/vmalloc.h>
17#include <linux/wait.h>
18
19#include <media/v4l2-common.h>
20#include <media/videobuf2-vmalloc.h>
21
22#include "uvc.h"
23
24/* ------------------------------------------------------------------------
25 * Video buffers queue management.
26 *
27 * Video queues is initialized by uvcg_queue_init(). The function performs
28 * basic initialization of the uvc_video_queue struct and never fails.
29 *
30 * Video buffers are managed by videobuf2. The driver uses a mutex to protect
31 * the videobuf2 queue operations by serializing calls to videobuf2 and a
32 * spinlock to protect the IRQ queue that holds the buffers to be processed by
33 * the driver.
34 */
35
36/* -----------------------------------------------------------------------------
37 * videobuf2 queue operations
38 */
39
40static int uvc_queue_setup(struct vb2_queue *vq,
41 unsigned int *nbuffers, unsigned int *nplanes,
42 unsigned int sizes[], struct device *alloc_devs[])
43{
44 struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
45 struct uvc_video *video = container_of(queue, struct uvc_video, queue);
46
47 if (*nbuffers > UVC_MAX_VIDEO_BUFFERS)
48 *nbuffers = UVC_MAX_VIDEO_BUFFERS;
49
50 *nplanes = 1;
51
52 sizes[0] = video->imagesize;
53
54 return 0;
55}
56
57static int uvc_buffer_prepare(struct vb2_buffer *vb)
58{
59 struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
60 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
61 struct uvc_buffer *buf = container_of(vbuf, struct uvc_buffer, buf);
62
63 if (vb->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
64 vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) {
65 uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n");
66 return -EINVAL;
67 }
68
69 if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED))
70 return -ENODEV;
71
72 buf->state = UVC_BUF_STATE_QUEUED;
73 buf->mem = vb2_plane_vaddr(vb, 0);
74 buf->length = vb2_plane_size(vb, 0);
75 if (vb->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
76 buf->bytesused = 0;
77 else
78 buf->bytesused = vb2_get_plane_payload(vb, 0);
79
80 return 0;
81}
82
83static void uvc_buffer_queue(struct vb2_buffer *vb)
84{
85 struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
86 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
87 struct uvc_buffer *buf = container_of(vbuf, struct uvc_buffer, buf);
88 unsigned long flags;
89
90 spin_lock_irqsave(&queue->irqlock, flags);
91
92 if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) {
93 list_add_tail(&buf->queue, &queue->irqqueue);
94 } else {
95 /* If the device is disconnected return the buffer to userspace
96 * directly. The next QBUF call will fail with -ENODEV.
97 */
98 buf->state = UVC_BUF_STATE_ERROR;
99 vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
100 }
101
102 spin_unlock_irqrestore(&queue->irqlock, flags);
103}
104
105static const struct vb2_ops uvc_queue_qops = {
106 .queue_setup = uvc_queue_setup,
107 .buf_prepare = uvc_buffer_prepare,
108 .buf_queue = uvc_buffer_queue,
109 .wait_prepare = vb2_ops_wait_prepare,
110 .wait_finish = vb2_ops_wait_finish,
111};
112
113int uvcg_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
114 struct mutex *lock)
115{
116 int ret;
117
118 queue->queue.type = type;
119 queue->queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
120 queue->queue.drv_priv = queue;
121 queue->queue.buf_struct_size = sizeof(struct uvc_buffer);
122 queue->queue.ops = &uvc_queue_qops;
123 queue->queue.lock = lock;
124 queue->queue.mem_ops = &vb2_vmalloc_memops;
125 queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
126 | V4L2_BUF_FLAG_TSTAMP_SRC_EOF;
127 ret = vb2_queue_init(&queue->queue);
128 if (ret)
129 return ret;
130
131 spin_lock_init(&queue->irqlock);
132 INIT_LIST_HEAD(&queue->irqqueue);
133 queue->flags = 0;
134
135 return 0;
136}
137
138/*
139 * Free the video buffers.
140 */
141void uvcg_free_buffers(struct uvc_video_queue *queue)
142{
143 vb2_queue_release(&queue->queue);
144}
145
146/*
147 * Allocate the video buffers.
148 */
149int uvcg_alloc_buffers(struct uvc_video_queue *queue,
150 struct v4l2_requestbuffers *rb)
151{
152 int ret;
153
154 ret = vb2_reqbufs(&queue->queue, rb);
155
156 return ret ? ret : rb->count;
157}
158
159int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
160{
161 return vb2_querybuf(&queue->queue, buf);
162}
163
164int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
165{
166 unsigned long flags;
167 int ret;
168
169 ret = vb2_qbuf(&queue->queue, NULL, buf);
170 if (ret < 0)
171 return ret;
172
173 spin_lock_irqsave(&queue->irqlock, flags);
174 ret = (queue->flags & UVC_QUEUE_PAUSED) != 0;
175 queue->flags &= ~UVC_QUEUE_PAUSED;
176 spin_unlock_irqrestore(&queue->irqlock, flags);
177 return ret;
178}
179
180/*
181 * Dequeue a video buffer. If nonblocking is false, block until a buffer is
182 * available.
183 */
184int uvcg_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
185 int nonblocking)
186{
187 return vb2_dqbuf(&queue->queue, buf, nonblocking);
188}
189
190/*
191 * Poll the video queue.
192 *
193 * This function implements video queue polling and is intended to be used by
194 * the device poll handler.
195 */
196__poll_t uvcg_queue_poll(struct uvc_video_queue *queue, struct file *file,
197 poll_table *wait)
198{
199 return vb2_poll(&queue->queue, file, wait);
200}
201
202int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
203{
204 return vb2_mmap(&queue->queue, vma);
205}
206
207#ifndef CONFIG_MMU
208/*
209 * Get unmapped area.
210 *
211 * NO-MMU arch need this function to make mmap() work correctly.
212 */
213unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
214 unsigned long pgoff)
215{
216 return vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0);
217}
218#endif
219
220/*
221 * Cancel the video buffers queue.
222 *
223 * Cancelling the queue marks all buffers on the irq queue as erroneous,
224 * wakes them up and removes them from the queue.
225 *
226 * If the disconnect parameter is set, further calls to uvc_queue_buffer will
227 * fail with -ENODEV.
228 *
229 * This function acquires the irq spinlock and can be called from interrupt
230 * context.
231 */
232void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect)
233{
234 struct uvc_buffer *buf;
235 unsigned long flags;
236
237 spin_lock_irqsave(&queue->irqlock, flags);
238 while (!list_empty(&queue->irqqueue)) {
239 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
240 queue);
241 list_del(&buf->queue);
242 buf->state = UVC_BUF_STATE_ERROR;
243 vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR);
244 }
245 /* This must be protected by the irqlock spinlock to avoid race
246 * conditions between uvc_queue_buffer and the disconnection event that
247 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
248 * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
249 * state outside the queue code.
250 */
251 if (disconnect)
252 queue->flags |= UVC_QUEUE_DISCONNECTED;
253 spin_unlock_irqrestore(&queue->irqlock, flags);
254}
255
256/*
257 * Enable or disable the video buffers queue.
258 *
259 * The queue must be enabled before starting video acquisition and must be
260 * disabled after stopping it. This ensures that the video buffers queue
261 * state can be properly initialized before buffers are accessed from the
262 * interrupt handler.
263 *
264 * Enabling the video queue initializes parameters (such as sequence number,
265 * sync pattern, ...). If the queue is already enabled, return -EBUSY.
266 *
267 * Disabling the video queue cancels the queue and removes all buffers from
268 * the main queue.
269 *
270 * This function can't be called from interrupt context. Use
271 * uvcg_queue_cancel() instead.
272 */
273int uvcg_queue_enable(struct uvc_video_queue *queue, int enable)
274{
275 unsigned long flags;
276 int ret = 0;
277
278 if (enable) {
279 ret = vb2_streamon(&queue->queue, queue->queue.type);
280 if (ret < 0)
281 return ret;
282
283 queue->sequence = 0;
284 queue->buf_used = 0;
285 } else {
286 ret = vb2_streamoff(&queue->queue, queue->queue.type);
287 if (ret < 0)
288 return ret;
289
290 spin_lock_irqsave(&queue->irqlock, flags);
291 INIT_LIST_HEAD(&queue->irqqueue);
292
293 /*
294 * FIXME: We need to clear the DISCONNECTED flag to ensure that
295 * applications will be able to queue buffers for the next
296 * streaming run. However, clearing it here doesn't guarantee
297 * that the device will be reconnected in the meantime.
298 */
299 queue->flags &= ~UVC_QUEUE_DISCONNECTED;
300 spin_unlock_irqrestore(&queue->irqlock, flags);
301 }
302
303 return ret;
304}
305
306/* called with &queue_irqlock held.. */
307struct uvc_buffer *uvcg_queue_next_buffer(struct uvc_video_queue *queue,
308 struct uvc_buffer *buf)
309{
310 struct uvc_buffer *nextbuf;
311
312 if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) &&
313 buf->length != buf->bytesused) {
314 buf->state = UVC_BUF_STATE_QUEUED;
315 vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0);
316 return buf;
317 }
318
319 list_del(&buf->queue);
320 if (!list_empty(&queue->irqqueue))
321 nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
322 queue);
323 else
324 nextbuf = NULL;
325
326 buf->buf.field = V4L2_FIELD_NONE;
327 buf->buf.sequence = queue->sequence++;
328 buf->buf.vb2_buf.timestamp = ktime_get_ns();
329
330 vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused);
331 vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE);
332
333 return nextbuf;
334}
335
336struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue)
337{
338 struct uvc_buffer *buf = NULL;
339
340 if (!list_empty(&queue->irqqueue))
341 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
342 queue);
343 else
344 queue->flags |= UVC_QUEUE_PAUSED;
345
346 return buf;
347}
348
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * uvc_queue.c -- USB Video Class driver - Buffers management
4 *
5 * Copyright (C) 2005-2010
6 * Laurent Pinchart (laurent.pinchart@ideasonboard.com)
7 */
8
9#include <linux/atomic.h>
10#include <linux/kernel.h>
11#include <linux/mm.h>
12#include <linux/list.h>
13#include <linux/module.h>
14#include <linux/usb.h>
15#include <linux/videodev2.h>
16#include <linux/vmalloc.h>
17#include <linux/wait.h>
18
19#include <media/v4l2-common.h>
20#include <media/videobuf2-dma-sg.h>
21#include <media/videobuf2-vmalloc.h>
22
23#include "uvc.h"
24#include "uvc_video.h"
25
26/* ------------------------------------------------------------------------
27 * Video buffers queue management.
28 *
29 * Video queues is initialized by uvcg_queue_init(). The function performs
30 * basic initialization of the uvc_video_queue struct and never fails.
31 *
32 * Video buffers are managed by videobuf2. The driver uses a mutex to protect
33 * the videobuf2 queue operations by serializing calls to videobuf2 and a
34 * spinlock to protect the IRQ queue that holds the buffers to be processed by
35 * the driver.
36 */
37
38/* -----------------------------------------------------------------------------
39 * videobuf2 queue operations
40 */
41
42static int uvc_queue_setup(struct vb2_queue *vq,
43 unsigned int *nbuffers, unsigned int *nplanes,
44 unsigned int sizes[], struct device *alloc_devs[])
45{
46 struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
47 struct uvc_video *video = container_of(queue, struct uvc_video, queue);
48
49 if (*nbuffers > UVC_MAX_VIDEO_BUFFERS)
50 *nbuffers = UVC_MAX_VIDEO_BUFFERS;
51 if (*nbuffers < UVCG_STREAMING_MIN_BUFFERS)
52 *nbuffers = UVCG_STREAMING_MIN_BUFFERS;
53
54 *nplanes = 1;
55
56 sizes[0] = video->imagesize;
57
58 return 0;
59}
60
61static int uvc_buffer_prepare(struct vb2_buffer *vb)
62{
63 struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
64 struct uvc_video *video = container_of(queue, struct uvc_video, queue);
65 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
66 struct uvc_buffer *buf = container_of(vbuf, struct uvc_buffer, buf);
67
68 if (vb->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
69 vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) {
70 uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n");
71 return -EINVAL;
72 }
73
74 if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED))
75 return -ENODEV;
76
77 buf->state = UVC_BUF_STATE_QUEUED;
78 if (queue->use_sg) {
79 buf->sgt = vb2_dma_sg_plane_desc(vb, 0);
80 buf->sg = buf->sgt->sgl;
81 } else {
82 buf->mem = vb2_plane_vaddr(vb, 0);
83 }
84 buf->length = vb2_plane_size(vb, 0);
85 if (vb->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
86 buf->bytesused = 0;
87 } else {
88 buf->bytesused = vb2_get_plane_payload(vb, 0);
89 buf->req_payload_size =
90 DIV_ROUND_UP(buf->bytesused +
91 (video->reqs_per_frame * UVCG_REQUEST_HEADER_LEN),
92 video->reqs_per_frame);
93 }
94
95 return 0;
96}
97
98static void uvc_buffer_queue(struct vb2_buffer *vb)
99{
100 struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
101 struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
102 struct uvc_buffer *buf = container_of(vbuf, struct uvc_buffer, buf);
103 unsigned long flags;
104
105 spin_lock_irqsave(&queue->irqlock, flags);
106
107 if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) {
108 list_add_tail(&buf->queue, &queue->irqqueue);
109 } else {
110 /*
111 * If the device is disconnected return the buffer to userspace
112 * directly. The next QBUF call will fail with -ENODEV.
113 */
114 buf->state = UVC_BUF_STATE_ERROR;
115 vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
116 }
117
118 spin_unlock_irqrestore(&queue->irqlock, flags);
119}
120
121static const struct vb2_ops uvc_queue_qops = {
122 .queue_setup = uvc_queue_setup,
123 .buf_prepare = uvc_buffer_prepare,
124 .buf_queue = uvc_buffer_queue,
125 .wait_prepare = vb2_ops_wait_prepare,
126 .wait_finish = vb2_ops_wait_finish,
127};
128
129int uvcg_queue_init(struct uvc_video_queue *queue, struct device *dev, enum v4l2_buf_type type,
130 struct mutex *lock)
131{
132 struct uvc_video *video = container_of(queue, struct uvc_video, queue);
133 struct usb_composite_dev *cdev = video->uvc->func.config->cdev;
134 int ret;
135
136 queue->queue.type = type;
137 queue->queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
138 queue->queue.drv_priv = queue;
139 queue->queue.buf_struct_size = sizeof(struct uvc_buffer);
140 queue->queue.ops = &uvc_queue_qops;
141 queue->queue.lock = lock;
142 if (cdev->gadget->sg_supported) {
143 queue->queue.mem_ops = &vb2_dma_sg_memops;
144 queue->use_sg = 1;
145 } else {
146 queue->queue.mem_ops = &vb2_vmalloc_memops;
147 }
148
149 queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY
150 | V4L2_BUF_FLAG_TSTAMP_SRC_EOF;
151 queue->queue.dev = dev;
152
153 ret = vb2_queue_init(&queue->queue);
154 if (ret)
155 return ret;
156
157 spin_lock_init(&queue->irqlock);
158 INIT_LIST_HEAD(&queue->irqqueue);
159 queue->flags = 0;
160
161 return 0;
162}
163
164/*
165 * Free the video buffers.
166 */
167void uvcg_free_buffers(struct uvc_video_queue *queue)
168{
169 vb2_queue_release(&queue->queue);
170}
171
172/*
173 * Allocate the video buffers.
174 */
175int uvcg_alloc_buffers(struct uvc_video_queue *queue,
176 struct v4l2_requestbuffers *rb)
177{
178 int ret;
179
180 ret = vb2_reqbufs(&queue->queue, rb);
181
182 return ret ? ret : rb->count;
183}
184
185int uvcg_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
186{
187 return vb2_querybuf(&queue->queue, buf);
188}
189
190int uvcg_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
191{
192 return vb2_qbuf(&queue->queue, NULL, buf);
193}
194
195/*
196 * Dequeue a video buffer. If nonblocking is false, block until a buffer is
197 * available.
198 */
199int uvcg_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
200 int nonblocking)
201{
202 return vb2_dqbuf(&queue->queue, buf, nonblocking);
203}
204
205/*
206 * Poll the video queue.
207 *
208 * This function implements video queue polling and is intended to be used by
209 * the device poll handler.
210 */
211__poll_t uvcg_queue_poll(struct uvc_video_queue *queue, struct file *file,
212 poll_table *wait)
213{
214 return vb2_poll(&queue->queue, file, wait);
215}
216
217int uvcg_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
218{
219 return vb2_mmap(&queue->queue, vma);
220}
221
222#ifndef CONFIG_MMU
223/*
224 * Get unmapped area.
225 *
226 * NO-MMU arch need this function to make mmap() work correctly.
227 */
228unsigned long uvcg_queue_get_unmapped_area(struct uvc_video_queue *queue,
229 unsigned long pgoff)
230{
231 return vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0);
232}
233#endif
234
235/*
236 * Cancel the video buffers queue.
237 *
238 * Cancelling the queue marks all buffers on the irq queue as erroneous,
239 * wakes them up and removes them from the queue.
240 *
241 * If the disconnect parameter is set, further calls to uvc_queue_buffer will
242 * fail with -ENODEV.
243 *
244 * This function acquires the irq spinlock and can be called from interrupt
245 * context.
246 */
247void uvcg_queue_cancel(struct uvc_video_queue *queue, int disconnect)
248{
249 struct uvc_buffer *buf;
250 unsigned long flags;
251
252 spin_lock_irqsave(&queue->irqlock, flags);
253 while (!list_empty(&queue->irqqueue)) {
254 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
255 queue);
256 list_del(&buf->queue);
257 buf->state = UVC_BUF_STATE_ERROR;
258 vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR);
259 }
260 queue->buf_used = 0;
261
262 /*
263 * This must be protected by the irqlock spinlock to avoid race
264 * conditions between uvc_queue_buffer and the disconnection event that
265 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
266 * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
267 * state outside the queue code.
268 */
269 if (disconnect)
270 queue->flags |= UVC_QUEUE_DISCONNECTED;
271 spin_unlock_irqrestore(&queue->irqlock, flags);
272}
273
274/*
275 * Enable or disable the video buffers queue.
276 *
277 * The queue must be enabled before starting video acquisition and must be
278 * disabled after stopping it. This ensures that the video buffers queue
279 * state can be properly initialized before buffers are accessed from the
280 * interrupt handler.
281 *
282 * Enabling the video queue initializes parameters (such as sequence number,
283 * sync pattern, ...). If the queue is already enabled, return -EBUSY.
284 *
285 * Disabling the video queue cancels the queue and removes all buffers from
286 * the main queue.
287 *
288 * This function can't be called from interrupt context. Use
289 * uvcg_queue_cancel() instead.
290 */
291int uvcg_queue_enable(struct uvc_video_queue *queue, int enable)
292{
293 unsigned long flags;
294 int ret = 0;
295
296 if (enable) {
297 ret = vb2_streamon(&queue->queue, queue->queue.type);
298 if (ret < 0)
299 return ret;
300
301 queue->sequence = 0;
302 queue->buf_used = 0;
303 queue->flags &= ~UVC_QUEUE_DROP_INCOMPLETE;
304 } else {
305 ret = vb2_streamoff(&queue->queue, queue->queue.type);
306 if (ret < 0)
307 return ret;
308
309 spin_lock_irqsave(&queue->irqlock, flags);
310 INIT_LIST_HEAD(&queue->irqqueue);
311
312 /*
313 * FIXME: We need to clear the DISCONNECTED flag to ensure that
314 * applications will be able to queue buffers for the next
315 * streaming run. However, clearing it here doesn't guarantee
316 * that the device will be reconnected in the meantime.
317 */
318 queue->flags &= ~UVC_QUEUE_DISCONNECTED;
319 spin_unlock_irqrestore(&queue->irqlock, flags);
320 }
321
322 return ret;
323}
324
325/* called with &queue_irqlock held.. */
326void uvcg_complete_buffer(struct uvc_video_queue *queue,
327 struct uvc_buffer *buf)
328{
329 if (queue->flags & UVC_QUEUE_DROP_INCOMPLETE) {
330 queue->flags &= ~UVC_QUEUE_DROP_INCOMPLETE;
331 buf->state = UVC_BUF_STATE_ERROR;
332 vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0);
333 vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_ERROR);
334 return;
335 }
336
337 buf->buf.field = V4L2_FIELD_NONE;
338 buf->buf.sequence = queue->sequence++;
339 buf->buf.vb2_buf.timestamp = ktime_get_ns();
340
341 vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused);
342 vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE);
343}
344
345struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue)
346{
347 struct uvc_buffer *buf = NULL;
348
349 if (!list_empty(&queue->irqqueue))
350 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
351 queue);
352
353 return buf;
354}
355