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authorAndrzej Pietrasiewicz <andrzej.p@samsung.com>2014-07-15 07:09:46 -0400
committerFelipe Balbi <balbi@ti.com>2014-07-16 13:50:36 -0400
commit00a2430ff07d4e0e0e7e24e02fd8adede333b797 (patch)
treefd6680b6a8941ac1a3149ae4b77f159701bb1a61 /drivers/usb/gadget/function/uvc_queue.c
parent90fccb529d241b55829701cfb9eb3086570f38b8 (diff)
usb: gadget: Gadget directory cleanup - group usb functions
The drivers/usb/gadget directory contains many files. Files which are related can be distributed into separate directories. This patch moves the USB functions implementations into a separate directory. Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com> Signed-off-by: Felipe Balbi <balbi@ti.com>
Diffstat (limited to 'drivers/usb/gadget/function/uvc_queue.c')
-rw-r--r--drivers/usb/gadget/function/uvc_queue.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/function/uvc_queue.c
new file mode 100644
index 000000000000..1c29bc954db9
--- /dev/null
+++ b/drivers/usb/gadget/function/uvc_queue.c
@@ -0,0 +1,407 @@
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.
11 */
12
13#include <linux/atomic.h>
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>
22
23#include <media/v4l2-common.h>
24#include <media/videobuf2-vmalloc.h>
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 *
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.
38 */
39
40/* -----------------------------------------------------------------------------
41 * videobuf2 queue operations
42 */
43
44static 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[])
47{
48 struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
49 struct uvc_video *video = container_of(queue, struct uvc_video, queue);
50
51 if (*nbuffers > UVC_MAX_VIDEO_BUFFERS)
52 *nbuffers = UVC_MAX_VIDEO_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_buffer *buf = container_of(vb, struct uvc_buffer, buf);
65
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 }
71
72 if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED))
73 return -ENODEV;
74
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);
82
83 return 0;
84}
85
86static 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;
91
92 spin_lock_irqsave(&queue->irqlock, flags);
93
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);
102 }
103
104 spin_unlock_irqrestore(&queue->irqlock, flags);
105}
106
107static 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
114static 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
121static 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 = uvc_wait_prepare,
126 .wait_finish = uvc_wait_finish,
127};
128
129static int uvc_queue_init(struct uvc_video_queue *queue,
130 enum v4l2_buf_type type)
131{
132 int ret;
133
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 queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
141 | V4L2_BUF_FLAG_TSTAMP_SRC_EOF;
142 ret = vb2_queue_init(&queue->queue);
143 if (ret)
144 return ret;
145
146 mutex_init(&queue->mutex);
147 spin_lock_init(&queue->irqlock);
148 INIT_LIST_HEAD(&queue->irqqueue);
149 queue->flags = 0;
150
151 return 0;
152}
153
154/*
155 * Free the video buffers.
156 */
157static void uvc_free_buffers(struct uvc_video_queue *queue)
158{
159 mutex_lock(&queue->mutex);
160 vb2_queue_release(&queue->queue);
161 mutex_unlock(&queue->mutex);
162}
163
164/*
165 * Allocate the video buffers.
166 */
167static int uvc_alloc_buffers(struct uvc_video_queue *queue,
168 struct v4l2_requestbuffers *rb)
169{
170 int ret;
171
172 mutex_lock(&queue->mutex);
173 ret = vb2_reqbufs(&queue->queue, rb);
174 mutex_unlock(&queue->mutex);
175
176 return ret ? ret : rb->count;
177}
178
179static int uvc_query_buffer(struct uvc_video_queue *queue,
180 struct v4l2_buffer *buf)
181{
182 int ret;
183
184 mutex_lock(&queue->mutex);
185 ret = vb2_querybuf(&queue->queue, buf);
186 mutex_unlock(&queue->mutex);
187
188 return ret;
189}
190
191static int uvc_queue_buffer(struct uvc_video_queue *queue,
192 struct v4l2_buffer *buf)
193{
194 unsigned long flags;
195 int ret;
196
197 mutex_lock(&queue->mutex);
198 ret = vb2_qbuf(&queue->queue, buf);
199 if (ret < 0)
200 goto done;
201
202 spin_lock_irqsave(&queue->irqlock, flags);
203 ret = (queue->flags & UVC_QUEUE_PAUSED) != 0;
204 queue->flags &= ~UVC_QUEUE_PAUSED;
205 spin_unlock_irqrestore(&queue->irqlock, flags);
206
207done:
208 mutex_unlock(&queue->mutex);
209 return ret;
210}
211
212/*
213 * Dequeue a video buffer. If nonblocking is false, block until a buffer is
214 * available.
215 */
216static int uvc_dequeue_buffer(struct uvc_video_queue *queue,
217 struct v4l2_buffer *buf, int nonblocking)
218{
219 int ret;
220
221 mutex_lock(&queue->mutex);
222 ret = vb2_dqbuf(&queue->queue, buf, nonblocking);
223 mutex_unlock(&queue->mutex);
224
225 return ret;
226}
227
228/*
229 * Poll the video queue.
230 *
231 * This function implements video queue polling and is intended to be used by
232 * the device poll handler.
233 */
234static unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
235 struct file *file, poll_table *wait)
236{
237 unsigned int ret;
238
239 mutex_lock(&queue->mutex);
240 ret = vb2_poll(&queue->queue, file, wait);
241 mutex_unlock(&queue->mutex);
242
243 return ret;
244}
245
246static int uvc_queue_mmap(struct uvc_video_queue *queue,
247 struct vm_area_struct *vma)
248{
249 int ret;
250
251 mutex_lock(&queue->mutex);
252 ret = vb2_mmap(&queue->queue, vma);
253 mutex_unlock(&queue->mutex);
254
255 return ret;
256}
257
258#ifndef CONFIG_MMU
259/*
260 * Get unmapped area.
261 *
262 * NO-MMU arch need this function to make mmap() work correctly.
263 */
264static unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
265 unsigned long pgoff)
266{
267 unsigned long ret;
268
269 mutex_lock(&queue->mutex);
270 ret = vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0);
271 mutex_unlock(&queue->mutex);
272 return ret;
273}
274#endif
275
276/*
277 * Cancel the video buffers queue.
278 *
279 * Cancelling the queue marks all buffers on the irq queue as erroneous,
280 * wakes them up and removes them from the queue.
281 *
282 * If the disconnect parameter is set, further calls to uvc_queue_buffer will
283 * fail with -ENODEV.
284 *
285 * This function acquires the irq spinlock and can be called from interrupt
286 * context.
287 */
288static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
289{
290 struct uvc_buffer *buf;
291 unsigned long flags;
292
293 spin_lock_irqsave(&queue->irqlock, flags);
294 while (!list_empty(&queue->irqqueue)) {
295 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
296 queue);
297 list_del(&buf->queue);
298 buf->state = UVC_BUF_STATE_ERROR;
299 vb2_buffer_done(&buf->buf, VB2_BUF_STATE_ERROR);
300 }
301 /* This must be protected by the irqlock spinlock to avoid race
302 * conditions between uvc_queue_buffer and the disconnection event that
303 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
304 * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
305 * state outside the queue code.
306 */
307 if (disconnect)
308 queue->flags |= UVC_QUEUE_DISCONNECTED;
309 spin_unlock_irqrestore(&queue->irqlock, flags);
310}
311
312/*
313 * Enable or disable the video buffers queue.
314 *
315 * The queue must be enabled before starting video acquisition and must be
316 * disabled after stopping it. This ensures that the video buffers queue
317 * state can be properly initialized before buffers are accessed from the
318 * interrupt handler.
319 *
320 * Enabling the video queue initializes parameters (such as sequence number,
321 * sync pattern, ...). If the queue is already enabled, return -EBUSY.
322 *
323 * Disabling the video queue cancels the queue and removes all buffers from
324 * the main queue.
325 *
326 * This function can't be called from interrupt context. Use
327 * uvc_queue_cancel() instead.
328 */
329static int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
330{
331 unsigned long flags;
332 int ret = 0;
333
334 mutex_lock(&queue->mutex);
335 if (enable) {
336 ret = vb2_streamon(&queue->queue, queue->queue.type);
337 if (ret < 0)
338 goto done;
339
340 queue->sequence = 0;
341 queue->buf_used = 0;
342 } else {
343 ret = vb2_streamoff(&queue->queue, queue->queue.type);
344 if (ret < 0)
345 goto done;
346
347 spin_lock_irqsave(&queue->irqlock, flags);
348 INIT_LIST_HEAD(&queue->irqqueue);
349
350 /*
351 * FIXME: We need to clear the DISCONNECTED flag to ensure that
352 * applications will be able to queue buffers for the next
353 * streaming run. However, clearing it here doesn't guarantee
354 * that the device will be reconnected in the meantime.
355 */
356 queue->flags &= ~UVC_QUEUE_DISCONNECTED;
357 spin_unlock_irqrestore(&queue->irqlock, flags);
358 }
359
360done:
361 mutex_unlock(&queue->mutex);
362 return ret;
363}
364
365/* called with &queue_irqlock held.. */
366static struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
367 struct uvc_buffer *buf)
368{
369 struct uvc_buffer *nextbuf;
370
371 if ((queue->flags & UVC_QUEUE_DROP_INCOMPLETE) &&
372 buf->length != buf->bytesused) {
373 buf->state = UVC_BUF_STATE_QUEUED;
374 vb2_set_plane_payload(&buf->buf, 0, 0);
375 return buf;
376 }
377
378 list_del(&buf->queue);
379 if (!list_empty(&queue->irqqueue))
380 nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
381 queue);
382 else
383 nextbuf = NULL;
384
385 buf->buf.v4l2_buf.field = V4L2_FIELD_NONE;
386 buf->buf.v4l2_buf.sequence = queue->sequence++;
387 v4l2_get_timestamp(&buf->buf.v4l2_buf.timestamp);
388
389 vb2_set_plane_payload(&buf->buf, 0, buf->bytesused);
390 vb2_buffer_done(&buf->buf, VB2_BUF_STATE_DONE);
391
392 return nextbuf;
393}
394
395static struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
396{
397 struct uvc_buffer *buf = NULL;
398
399 if (!list_empty(&queue->irqqueue))
400 buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
401 queue);
402 else
403 queue->flags |= UVC_QUEUE_PAUSED;
404
405 return buf;
406}
407