| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Laurent Pinchart | 6974 | 72.28% | 56 | 48.28% |
| Guennadi Liakhovetski | 783 | 8.11% | 2 | 1.72% |
| Ricardo Ribalda Delgado | 507 | 5.25% | 10 | 8.62% |
| Kieran Bingham | 426 | 4.41% | 9 | 7.76% |
| Alexey Fisher | 422 | 4.37% | 1 | 0.86% |
| Benjamin Drung | 93 | 0.96% | 1 | 0.86% |
| Oleksij Rempel | 65 | 0.67% | 1 | 0.86% |
| Arnd Bergmann | 55 | 0.57% | 2 | 1.72% |
| Joe Perches | 49 | 0.51% | 1 | 0.86% |
| ming_qian | 46 | 0.48% | 1 | 0.86% |
| Stephan Lachowsky | 29 | 0.30% | 1 | 0.86% |
| Kees Cook | 27 | 0.28% | 2 | 1.72% |
| Anton Leontiev | 21 | 0.22% | 1 | 0.86% |
| Johan Hovold | 17 | 0.18% | 1 | 0.86% |
| Hans Verkuil | 13 | 0.13% | 2 | 1.72% |
| Olivier Langlois | 13 | 0.13% | 1 | 0.86% |
| Lei Ming | 12 | 0.12% | 2 | 1.72% |
| Al Cooper | 11 | 0.11% | 1 | 0.86% |
| Thomas Pugliese | 10 | 0.10% | 1 | 0.86% |
| Sakari Ailus | 9 | 0.09% | 1 | 0.86% |
| Jayakrishnan Memana | 9 | 0.09% | 1 | 0.86% |
| William Manley | 9 | 0.09% | 1 | 0.86% |
| Nicolas Dufresne | 8 | 0.08% | 1 | 0.86% |
| Junghak Sung | 7 | 0.07% | 2 | 1.72% |
| Baoyou Xie | 6 | 0.06% | 1 | 0.86% |
| Jasmin J | 6 | 0.06% | 1 | 0.86% |
| Gustavo A. R. Silva | 4 | 0.04% | 1 | 0.86% |
| Julia Lawall | 3 | 0.03% | 1 | 0.86% |
| Oliver Neukum | 3 | 0.03% | 1 | 0.86% |
| Linus Torvalds (pre-git) | 2 | 0.02% | 1 | 0.86% |
| Hangyu Hua | 2 | 0.02% | 1 | 0.86% |
| Thomas Gleixner | 2 | 0.02% | 1 | 0.86% |
| Jun Chen | 1 | 0.01% | 1 | 0.86% |
| Slark Xiao | 1 | 0.01% | 1 | 0.86% |
| Arun Sharma | 1 | 0.01% | 1 | 0.86% |
| Linus Torvalds | 1 | 0.01% | 1 | 0.86% |
| Dan Carpenter | 1 | 0.01% | 1 | 0.86% |
| Lucas De Marchi | 1 | 0.01% | 1 | 0.86% |
| Total | 9649 | 116 |
// SPDX-License-Identifier: GPL-2.0-or-later /* * uvc_video.c -- USB Video Class driver - Video handling * * Copyright (C) 2005-2010 * Laurent Pinchart (laurent.pinchart@ideasonboard.com) */ #include <linux/dma-mapping.h> #include <linux/highmem.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/usb.h> #include <linux/usb/hcd.h> #include <linux/videodev2.h> #include <linux/vmalloc.h> #include <linux/wait.h> #include <linux/atomic.h> #include <asm/unaligned.h> #include <media/v4l2-common.h> #include "uvcvideo.h" /* ------------------------------------------------------------------------ * UVC Controls */ static int __uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit, u8 intfnum, u8 cs, void *data, u16 size, int timeout) { u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0) : usb_sndctrlpipe(dev->udev, 0); type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT; return usb_control_msg(dev->udev, pipe, query, type, cs << 8, unit << 8 | intfnum, data, size, timeout); } static const char *uvc_query_name(u8 query) { switch (query) { case UVC_SET_CUR: return "SET_CUR"; case UVC_GET_CUR: return "GET_CUR"; case UVC_GET_MIN: return "GET_MIN"; case UVC_GET_MAX: return "GET_MAX"; case UVC_GET_RES: return "GET_RES"; case UVC_GET_LEN: return "GET_LEN"; case UVC_GET_INFO: return "GET_INFO"; case UVC_GET_DEF: return "GET_DEF"; default: return "<invalid>"; } } int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit, u8 intfnum, u8 cs, void *data, u16 size) { int ret; u8 error; u8 tmp; ret = __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size, UVC_CTRL_CONTROL_TIMEOUT); if (likely(ret == size)) return 0; if (ret != -EPIPE) { dev_err(&dev->udev->dev, "Failed to query (%s) UVC control %u on unit %u: %d (exp. %u).\n", uvc_query_name(query), cs, unit, ret, size); return ret < 0 ? ret : -EPIPE; } /* Reuse data[0] to request the error code. */ tmp = *(u8 *)data; ret = __uvc_query_ctrl(dev, UVC_GET_CUR, 0, intfnum, UVC_VC_REQUEST_ERROR_CODE_CONTROL, data, 1, UVC_CTRL_CONTROL_TIMEOUT); error = *(u8 *)data; *(u8 *)data = tmp; if (ret != 1) return ret < 0 ? ret : -EPIPE; uvc_dbg(dev, CONTROL, "Control error %u\n", error); switch (error) { case 0: /* Cannot happen - we received a STALL */ return -EPIPE; case 1: /* Not ready */ return -EBUSY; case 2: /* Wrong state */ return -EACCES; case 3: /* Power */ return -EREMOTE; case 4: /* Out of range */ return -ERANGE; case 5: /* Invalid unit */ case 6: /* Invalid control */ case 7: /* Invalid Request */ /* * The firmware has not properly implemented * the control or there has been a HW error. */ return -EIO; case 8: /* Invalid value within range */ return -EINVAL; default: /* reserved or unknown */ break; } return -EPIPE; } static const struct usb_device_id elgato_cam_link_4k = { USB_DEVICE(0x0fd9, 0x0066) }; static void uvc_fixup_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl) { const struct uvc_format *format = NULL; const struct uvc_frame *frame = NULL; unsigned int i; /* * The response of the Elgato Cam Link 4K is incorrect: The second byte * contains bFormatIndex (instead of being the second byte of bmHint). * The first byte is always zero. The third byte is always 1. * * The UVC 1.5 class specification defines the first five bits in the * bmHint bitfield. The remaining bits are reserved and should be zero. * Therefore a valid bmHint will be less than 32. * * Latest Elgato Cam Link 4K firmware as of 2021-03-23 needs this fix. * MCU: 20.02.19, FPGA: 67 */ if (usb_match_one_id(stream->dev->intf, &elgato_cam_link_4k) && ctrl->bmHint > 255) { u8 corrected_format_index = ctrl->bmHint >> 8; uvc_dbg(stream->dev, VIDEO, "Correct USB video probe response from {bmHint: 0x%04x, bFormatIndex: %u} to {bmHint: 0x%04x, bFormatIndex: %u}\n", ctrl->bmHint, ctrl->bFormatIndex, 1, corrected_format_index); ctrl->bmHint = 1; ctrl->bFormatIndex = corrected_format_index; } for (i = 0; i < stream->nformats; ++i) { if (stream->formats[i].index == ctrl->bFormatIndex) { format = &stream->formats[i]; break; } } if (format == NULL) return; for (i = 0; i < format->nframes; ++i) { if (format->frames[i].bFrameIndex == ctrl->bFrameIndex) { frame = &format->frames[i]; break; } } if (frame == NULL) return; if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) || (ctrl->dwMaxVideoFrameSize == 0 && stream->dev->uvc_version < 0x0110)) ctrl->dwMaxVideoFrameSize = frame->dwMaxVideoFrameBufferSize; /* * The "TOSHIBA Web Camera - 5M" Chicony device (04f2:b50b) seems to * compute the bandwidth on 16 bits and erroneously sign-extend it to * 32 bits, resulting in a huge bandwidth value. Detect and fix that * condition by setting the 16 MSBs to 0 when they're all equal to 1. */ if ((ctrl->dwMaxPayloadTransferSize & 0xffff0000) == 0xffff0000) ctrl->dwMaxPayloadTransferSize &= ~0xffff0000; if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) && stream->dev->quirks & UVC_QUIRK_FIX_BANDWIDTH && stream->intf->num_altsetting > 1) { u32 interval; u32 bandwidth; interval = (ctrl->dwFrameInterval > 100000) ? ctrl->dwFrameInterval : frame->dwFrameInterval[0]; /* * Compute a bandwidth estimation by multiplying the frame * size by the number of video frames per second, divide the * result by the number of USB frames (or micro-frames for * high-speed devices) per second and add the UVC header size * (assumed to be 12 bytes long). */ bandwidth = frame->wWidth * frame->wHeight / 8 * format->bpp; bandwidth *= 10000000 / interval + 1; bandwidth /= 1000; if (stream->dev->udev->speed == USB_SPEED_HIGH) bandwidth /= 8; bandwidth += 12; /* * The bandwidth estimate is too low for many cameras. Don't use * maximum packet sizes lower than 1024 bytes to try and work * around the problem. According to measurements done on two * different camera models, the value is high enough to get most * resolutions working while not preventing two simultaneous * VGA streams at 15 fps. */ bandwidth = max_t(u32, bandwidth, 1024); ctrl->dwMaxPayloadTransferSize = bandwidth; } } static size_t uvc_video_ctrl_size(struct uvc_streaming *stream) { /* * Return the size of the video probe and commit controls, which depends * on the protocol version. */ if (stream->dev->uvc_version < 0x0110) return 26; else if (stream->dev->uvc_version < 0x0150) return 34; else return 48; } static int uvc_get_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl, int probe, u8 query) { u16 size = uvc_video_ctrl_size(stream); u8 *data; int ret; if ((stream->dev->quirks & UVC_QUIRK_PROBE_DEF) && query == UVC_GET_DEF) return -EIO; data = kmalloc(size, GFP_KERNEL); if (data == NULL) return -ENOMEM; ret = __uvc_query_ctrl(stream->dev, query, 0, stream->intfnum, probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data, size, uvc_timeout_param); if ((query == UVC_GET_MIN || query == UVC_GET_MAX) && ret == 2) { /* * Some cameras, mostly based on Bison Electronics chipsets, * answer a GET_MIN or GET_MAX request with the wCompQuality * field only. */ uvc_warn_once(stream->dev, UVC_WARN_MINMAX, "UVC non " "compliance - GET_MIN/MAX(PROBE) incorrectly " "supported. Enabling workaround.\n"); memset(ctrl, 0, sizeof(*ctrl)); ctrl->wCompQuality = le16_to_cpup((__le16 *)data); ret = 0; goto out; } else if (query == UVC_GET_DEF && probe == 1 && ret != size) { /* * Many cameras don't support the GET_DEF request on their * video probe control. Warn once and return, the caller will * fall back to GET_CUR. */ uvc_warn_once(stream->dev, UVC_WARN_PROBE_DEF, "UVC non " "compliance - GET_DEF(PROBE) not supported. " "Enabling workaround.\n"); ret = -EIO; goto out; } else if (ret != size) { dev_err(&stream->intf->dev, "Failed to query (%u) UVC %s control : %d (exp. %u).\n", query, probe ? "probe" : "commit", ret, size); ret = (ret == -EPROTO) ? -EPROTO : -EIO; goto out; } ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]); ctrl->bFormatIndex = data[2]; ctrl->bFrameIndex = data[3]; ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]); ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]); ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]); ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]); ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]); ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]); ctrl->dwMaxVideoFrameSize = get_unaligned_le32(&data[18]); ctrl->dwMaxPayloadTransferSize = get_unaligned_le32(&data[22]); if (size >= 34) { ctrl->dwClockFrequency = get_unaligned_le32(&data[26]); ctrl->bmFramingInfo = data[30]; ctrl->bPreferedVersion = data[31]; ctrl->bMinVersion = data[32]; ctrl->bMaxVersion = data[33]; } else { ctrl->dwClockFrequency = stream->dev->clock_frequency; ctrl->bmFramingInfo = 0; ctrl->bPreferedVersion = 0; ctrl->bMinVersion = 0; ctrl->bMaxVersion = 0; } /* * Some broken devices return null or wrong dwMaxVideoFrameSize and * dwMaxPayloadTransferSize fields. Try to get the value from the * format and frame descriptors. */ uvc_fixup_video_ctrl(stream, ctrl); ret = 0; out: kfree(data); return ret; } static int uvc_set_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl, int probe) { u16 size = uvc_video_ctrl_size(stream); u8 *data; int ret; data = kzalloc(size, GFP_KERNEL); if (data == NULL) return -ENOMEM; *(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint); data[2] = ctrl->bFormatIndex; data[3] = ctrl->bFrameIndex; *(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval); *(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate); *(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate); *(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality); *(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize); *(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay); put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]); put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]); if (size >= 34) { put_unaligned_le32(ctrl->dwClockFrequency, &data[26]); data[30] = ctrl->bmFramingInfo; data[31] = ctrl->bPreferedVersion; data[32] = ctrl->bMinVersion; data[33] = ctrl->bMaxVersion; } ret = __uvc_query_ctrl(stream->dev, UVC_SET_CUR, 0, stream->intfnum, probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data, size, uvc_timeout_param); if (ret != size) { dev_err(&stream->intf->dev, "Failed to set UVC %s control : %d (exp. %u).\n", probe ? "probe" : "commit", ret, size); ret = -EIO; } kfree(data); return ret; } int uvc_probe_video(struct uvc_streaming *stream, struct uvc_streaming_control *probe) { struct uvc_streaming_control probe_min, probe_max; unsigned int i; int ret; /* * Perform probing. The device should adjust the requested values * according to its capabilities. However, some devices, namely the * first generation UVC Logitech webcams, don't implement the Video * Probe control properly, and just return the needed bandwidth. For * that reason, if the needed bandwidth exceeds the maximum available * bandwidth, try to lower the quality. */ ret = uvc_set_video_ctrl(stream, probe, 1); if (ret < 0) goto done; /* Get the minimum and maximum values for compression settings. */ if (!(stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX)) { ret = uvc_get_video_ctrl(stream, &probe_min, 1, UVC_GET_MIN); if (ret < 0) goto done; ret = uvc_get_video_ctrl(stream, &probe_max, 1, UVC_GET_MAX); if (ret < 0) goto done; probe->wCompQuality = probe_max.wCompQuality; } for (i = 0; i < 2; ++i) { ret = uvc_set_video_ctrl(stream, probe, 1); if (ret < 0) goto done; ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR); if (ret < 0) goto done; if (stream->intf->num_altsetting == 1) break; if (probe->dwMaxPayloadTransferSize <= stream->maxpsize) break; if (stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX) { ret = -ENOSPC; goto done; } /* TODO: negotiate compression parameters */ probe->wKeyFrameRate = probe_min.wKeyFrameRate; probe->wPFrameRate = probe_min.wPFrameRate; probe->wCompQuality = probe_max.wCompQuality; probe->wCompWindowSize = probe_min.wCompWindowSize; } done: return ret; } static int uvc_commit_video(struct uvc_streaming *stream, struct uvc_streaming_control *probe) { return uvc_set_video_ctrl(stream, probe, 0); } /* ----------------------------------------------------------------------------- * Clocks and timestamps */ static inline ktime_t uvc_video_get_time(void) { if (uvc_clock_param == CLOCK_MONOTONIC) return ktime_get(); else return ktime_get_real(); } static void uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf, const u8 *data, int len) { struct uvc_clock_sample *sample; unsigned int header_size; bool has_pts = false; bool has_scr = false; unsigned long flags; ktime_t time; u16 host_sof; u16 dev_sof; switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) { case UVC_STREAM_PTS | UVC_STREAM_SCR: header_size = 12; has_pts = true; has_scr = true; break; case UVC_STREAM_PTS: header_size = 6; has_pts = true; break; case UVC_STREAM_SCR: header_size = 8; has_scr = true; break; default: header_size = 2; break; } /* Check for invalid headers. */ if (len < header_size) return; /* * Extract the timestamps: * * - store the frame PTS in the buffer structure * - if the SCR field is present, retrieve the host SOF counter and * kernel timestamps and store them with the SCR STC and SOF fields * in the ring buffer */ if (has_pts && buf != NULL) buf->pts = get_unaligned_le32(&data[2]); if (!has_scr) return; /* * To limit the amount of data, drop SCRs with an SOF identical to the * previous one. This filtering is also needed to support UVC 1.5, where * all the data packets of the same frame contains the same SOF. In that * case only the first one will match the host_sof. */ dev_sof = get_unaligned_le16(&data[header_size - 2]); if (dev_sof == stream->clock.last_sof) return; stream->clock.last_sof = dev_sof; host_sof = usb_get_current_frame_number(stream->dev->udev); time = uvc_video_get_time(); /* * The UVC specification allows device implementations that can't obtain * the USB frame number to keep their own frame counters as long as they * match the size and frequency of the frame number associated with USB * SOF tokens. The SOF values sent by such devices differ from the USB * SOF tokens by a fixed offset that needs to be estimated and accounted * for to make timestamp recovery as accurate as possible. * * The offset is estimated the first time a device SOF value is received * as the difference between the host and device SOF values. As the two * SOF values can differ slightly due to transmission delays, consider * that the offset is null if the difference is not higher than 10 ms * (negative differences can not happen and are thus considered as an * offset). The video commit control wDelay field should be used to * compute a dynamic threshold instead of using a fixed 10 ms value, but * devices don't report reliable wDelay values. * * See uvc_video_clock_host_sof() for an explanation regarding why only * the 8 LSBs of the delta are kept. */ if (stream->clock.sof_offset == (u16)-1) { u16 delta_sof = (host_sof - dev_sof) & 255; if (delta_sof >= 10) stream->clock.sof_offset = delta_sof; else stream->clock.sof_offset = 0; } dev_sof = (dev_sof + stream->clock.sof_offset) & 2047; spin_lock_irqsave(&stream->clock.lock, flags); sample = &stream->clock.samples[stream->clock.head]; sample->dev_stc = get_unaligned_le32(&data[header_size - 6]); sample->dev_sof = dev_sof; sample->host_sof = host_sof; sample->host_time = time; /* Update the sliding window head and count. */ stream->clock.head = (stream->clock.head + 1) % stream->clock.size; if (stream->clock.count < stream->clock.size) stream->clock.count++; spin_unlock_irqrestore(&stream->clock.lock, flags); } static void uvc_video_clock_reset(struct uvc_streaming *stream) { struct uvc_clock *clock = &stream->clock; clock->head = 0; clock->count = 0; clock->last_sof = -1; clock->sof_offset = -1; } static int uvc_video_clock_init(struct uvc_streaming *stream) { struct uvc_clock *clock = &stream->clock; spin_lock_init(&clock->lock); clock->size = 32; clock->samples = kmalloc_array(clock->size, sizeof(*clock->samples), GFP_KERNEL); if (clock->samples == NULL) return -ENOMEM; uvc_video_clock_reset(stream); return 0; } static void uvc_video_clock_cleanup(struct uvc_streaming *stream) { kfree(stream->clock.samples); stream->clock.samples = NULL; } /* * uvc_video_clock_host_sof - Return the host SOF value for a clock sample * * Host SOF counters reported by usb_get_current_frame_number() usually don't * cover the whole 11-bits SOF range (0-2047) but are limited to the HCI frame * schedule window. They can be limited to 8, 9 or 10 bits depending on the host * controller and its configuration. * * We thus need to recover the SOF value corresponding to the host frame number. * As the device and host frame numbers are sampled in a short interval, the * difference between their values should be equal to a small delta plus an * integer multiple of 256 caused by the host frame number limited precision. * * To obtain the recovered host SOF value, compute the small delta by masking * the high bits of the host frame counter and device SOF difference and add it * to the device SOF value. */ static u16 uvc_video_clock_host_sof(const struct uvc_clock_sample *sample) { /* The delta value can be negative. */ s8 delta_sof; delta_sof = (sample->host_sof - sample->dev_sof) & 255; return (sample->dev_sof + delta_sof) & 2047; } /* * uvc_video_clock_update - Update the buffer timestamp * * This function converts the buffer PTS timestamp to the host clock domain by * going through the USB SOF clock domain and stores the result in the V4L2 * buffer timestamp field. * * The relationship between the device clock and the host clock isn't known. * However, the device and the host share the common USB SOF clock which can be * used to recover that relationship. * * The relationship between the device clock and the USB SOF clock is considered * to be linear over the clock samples sliding window and is given by * * SOF = m * PTS + p * * Several methods to compute the slope (m) and intercept (p) can be used. As * the clock drift should be small compared to the sliding window size, we * assume that the line that goes through the points at both ends of the window * is a good approximation. Naming those points P1 and P2, we get * * SOF = (SOF2 - SOF1) / (STC2 - STC1) * PTS * + (SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1) * * or * * SOF = ((SOF2 - SOF1) * PTS + SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1) (1) * * to avoid losing precision in the division. Similarly, the host timestamp is * computed with * * TS = ((TS2 - TS1) * SOF + TS1 * SOF2 - TS2 * SOF1) / (SOF2 - SOF1) (2) * * SOF values are coded on 11 bits by USB. We extend their precision with 16 * decimal bits, leading to a 11.16 coding. * * TODO: To avoid surprises with device clock values, PTS/STC timestamps should * be normalized using the nominal device clock frequency reported through the * UVC descriptors. * * Both the PTS/STC and SOF counters roll over, after a fixed but device * specific amount of time for PTS/STC and after 2048ms for SOF. As long as the * sliding window size is smaller than the rollover period, differences computed * on unsigned integers will produce the correct result. However, the p term in * the linear relations will be miscomputed. * * To fix the issue, we subtract a constant from the PTS and STC values to bring * PTS to half the 32 bit STC range. The sliding window STC values then fit into * the 32 bit range without any rollover. * * Similarly, we add 2048 to the device SOF values to make sure that the SOF * computed by (1) will never be smaller than 0. This offset is then compensated * by adding 2048 to the SOF values used in (2). However, this doesn't prevent * rollovers between (1) and (2): the SOF value computed by (1) can be slightly * lower than 4096, and the host SOF counters can have rolled over to 2048. This * case is handled by subtracting 2048 from the SOF value if it exceeds the host * SOF value at the end of the sliding window. * * Finally we subtract a constant from the host timestamps to bring the first * timestamp of the sliding window to 1s. */ void uvc_video_clock_update(struct uvc_streaming *stream, struct vb2_v4l2_buffer *vbuf, struct uvc_buffer *buf) { struct uvc_clock *clock = &stream->clock; struct uvc_clock_sample *first; struct uvc_clock_sample *last; unsigned long flags; u64 timestamp; u32 delta_stc; u32 y1, y2; u32 x1, x2; u32 mean; u32 sof; u64 y; if (!uvc_hw_timestamps_param) return; /* * We will get called from __vb2_queue_cancel() if there are buffers * done but not dequeued by the user, but the sample array has already * been released at that time. Just bail out in that case. */ if (!clock->samples) return; spin_lock_irqsave(&clock->lock, flags); if (clock->count < clock->size) goto done; first = &clock->samples[clock->head]; last = &clock->samples[(clock->head - 1) % clock->size]; /* First step, PTS to SOF conversion. */ delta_stc = buf->pts - (1UL << 31); x1 = first->dev_stc - delta_stc; x2 = last->dev_stc - delta_stc; if (x1 == x2) goto done; y1 = (first->dev_sof + 2048) << 16; y2 = (last->dev_sof + 2048) << 16; if (y2 < y1) y2 += 2048 << 16; y = (u64)(y2 - y1) * (1ULL << 31) + (u64)y1 * (u64)x2 - (u64)y2 * (u64)x1; y = div_u64(y, x2 - x1); sof = y; uvc_dbg(stream->dev, CLOCK, "%s: PTS %u y %llu.%06llu SOF %u.%06llu (x1 %u x2 %u y1 %u y2 %u SOF offset %u)\n", stream->dev->name, buf->pts, y >> 16, div_u64((y & 0xffff) * 1000000, 65536), sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536), x1, x2, y1, y2, clock->sof_offset); /* Second step, SOF to host clock conversion. */ x1 = (uvc_video_clock_host_sof(first) + 2048) << 16; x2 = (uvc_video_clock_host_sof(last) + 2048) << 16; if (x2 < x1) x2 += 2048 << 16; if (x1 == x2) goto done; y1 = NSEC_PER_SEC; y2 = (u32)ktime_to_ns(ktime_sub(last->host_time, first->host_time)) + y1; /* * Interpolated and host SOF timestamps can wrap around at slightly * different times. Handle this by adding or removing 2048 to or from * the computed SOF value to keep it close to the SOF samples mean * value. */ mean = (x1 + x2) / 2; if (mean - (1024 << 16) > sof) sof += 2048 << 16; else if (sof > mean + (1024 << 16)) sof -= 2048 << 16; y = (u64)(y2 - y1) * (u64)sof + (u64)y1 * (u64)x2 - (u64)y2 * (u64)x1; y = div_u64(y, x2 - x1); timestamp = ktime_to_ns(first->host_time) + y - y1; uvc_dbg(stream->dev, CLOCK, "%s: SOF %u.%06llu y %llu ts %llu buf ts %llu (x1 %u/%u/%u x2 %u/%u/%u y1 %u y2 %u)\n", stream->dev->name, sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536), y, timestamp, vbuf->vb2_buf.timestamp, x1, first->host_sof, first->dev_sof, x2, last->host_sof, last->dev_sof, y1, y2); /* Update the V4L2 buffer. */ vbuf->vb2_buf.timestamp = timestamp; done: spin_unlock_irqrestore(&clock->lock, flags); } /* ------------------------------------------------------------------------ * Stream statistics */ static void uvc_video_stats_decode(struct uvc_streaming *stream, const u8 *data, int len) { unsigned int header_size; bool has_pts = false; bool has_scr = false; u16 scr_sof; u32 scr_stc; u32 pts; if (stream->stats.stream.nb_frames == 0 && stream->stats.frame.nb_packets == 0) stream->stats.stream.start_ts = ktime_get(); switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) { case UVC_STREAM_PTS | UVC_STREAM_SCR: header_size = 12; has_pts = true; has_scr = true; break; case UVC_STREAM_PTS: header_size = 6; has_pts = true; break; case UVC_STREAM_SCR: header_size = 8; has_scr = true; break; default: header_size = 2; break; } /* Check for invalid headers. */ if (len < header_size || data[0] < header_size) { stream->stats.frame.nb_invalid++; return; } /* Extract the timestamps. */ if (has_pts) pts = get_unaligned_le32(&data[2]); if (has_scr) { scr_stc = get_unaligned_le32(&data[header_size - 6]); scr_sof = get_unaligned_le16(&data[header_size - 2]); } /* Is PTS constant through the whole frame ? */ if (has_pts && stream->stats.frame.nb_pts) { if (stream->stats.frame.pts != pts) { stream->stats.frame.nb_pts_diffs++; stream->stats.frame.last_pts_diff = stream->stats.frame.nb_packets; } } if (has_pts) { stream->stats.frame.nb_pts++; stream->stats.frame.pts = pts; } /* * Do all frames have a PTS in their first non-empty packet, or before * their first empty packet ? */ if (stream->stats.frame.size == 0) { if (len > header_size) stream->stats.frame.has_initial_pts = has_pts; if (len == header_size && has_pts) stream->stats.frame.has_early_pts = true; } /* Do the SCR.STC and SCR.SOF fields vary through the frame ? */ if (has_scr && stream->stats.frame.nb_scr) { if (stream->stats.frame.scr_stc != scr_stc) stream->stats.frame.nb_scr_diffs++; } if (has_scr) { /* Expand the SOF counter to 32 bits and store its value. */ if (stream->stats.stream.nb_frames > 0 || stream->stats.frame.nb_scr > 0) stream->stats.stream.scr_sof_count += (scr_sof - stream->stats.stream.scr_sof) % 2048; stream->stats.stream.scr_sof = scr_sof; stream->stats.frame.nb_scr++; stream->stats.frame.scr_stc = scr_stc; stream->stats.frame.scr_sof = scr_sof; if (scr_sof < stream->stats.stream.min_sof) stream->stats.stream.min_sof = scr_sof; if (scr_sof > stream->stats.stream.max_sof) stream->stats.stream.max_sof = scr_sof; } /* Record the first non-empty packet number. */ if (stream->stats.frame.size == 0 && len > header_size) stream->stats.frame.first_data = stream->stats.frame.nb_packets; /* Update the frame size. */ stream->stats.frame.size += len - header_size; /* Update the packets counters. */ stream->stats.frame.nb_packets++; if (len <= header_size) stream->stats.frame.nb_empty++; if (data[1] & UVC_STREAM_ERR) stream->stats.frame.nb_errors++; } static void uvc_video_stats_update(struct uvc_streaming *stream) { struct uvc_stats_frame *frame = &stream->stats.frame; uvc_dbg(stream->dev, STATS, "frame %u stats: %u/%u/%u packets, %u/%u/%u pts (%searly %sinitial), %u/%u scr, last pts/stc/sof %u/%u/%u\n", stream->sequence, frame->first_data, frame->nb_packets - frame->nb_empty, frame->nb_packets, frame->nb_pts_diffs, frame->last_pts_diff, frame->nb_pts, frame->has_early_pts ? "" : "!", frame->has_initial_pts ? "" : "!", frame->nb_scr_diffs, frame->nb_scr, frame->pts, frame->scr_stc, frame->scr_sof); stream->stats.stream.nb_frames++; stream->stats.stream.nb_packets += stream->stats.frame.nb_packets; stream->stats.stream.nb_empty += stream->stats.frame.nb_empty; stream->stats.stream.nb_errors += stream->stats.frame.nb_errors; stream->stats.stream.nb_invalid += stream->stats.frame.nb_invalid; if (frame->has_early_pts) stream->stats.stream.nb_pts_early++; if (frame->has_initial_pts) stream->stats.stream.nb_pts_initial++; if (frame->last_pts_diff <= frame->first_data) stream->stats.stream.nb_pts_constant++; if (frame->nb_scr >= frame->nb_packets - frame->nb_empty) stream->stats.stream.nb_scr_count_ok++; if (frame->nb_scr_diffs + 1 == frame->nb_scr) stream->stats.stream.nb_scr_diffs_ok++; memset(&stream->stats.frame, 0, sizeof(stream->stats.frame)); } size_t uvc_video_stats_dump(struct uvc_streaming *stream, char *buf, size_t size) { unsigned int scr_sof_freq; unsigned int duration; size_t count = 0; /* * Compute the SCR.SOF frequency estimate. At the nominal 1kHz SOF * frequency this will not overflow before more than 1h. */ duration = ktime_ms_delta(stream->stats.stream.stop_ts, stream->stats.stream.start_ts); if (duration != 0) scr_sof_freq = stream->stats.stream.scr_sof_count * 1000 / duration; else scr_sof_freq = 0; count += scnprintf(buf + count, size - count, "frames: %u\npackets: %u\nempty: %u\n" "errors: %u\ninvalid: %u\n", stream->stats.stream.nb_frames, stream->stats.stream.nb_packets, stream->stats.stream.nb_empty, stream->stats.stream.nb_errors, stream->stats.stream.nb_invalid); count += scnprintf(buf + count, size - count, "pts: %u early, %u initial, %u ok\n", stream->stats.stream.nb_pts_early, stream->stats.stream.nb_pts_initial, stream->stats.stream.nb_pts_constant); count += scnprintf(buf + count, size - count, "scr: %u count ok, %u diff ok\n", stream->stats.stream.nb_scr_count_ok, stream->stats.stream.nb_scr_diffs_ok); count += scnprintf(buf + count, size - count, "sof: %u <= sof <= %u, freq %u.%03u kHz\n", stream->stats.stream.min_sof, stream->stats.stream.max_sof, scr_sof_freq / 1000, scr_sof_freq % 1000); return count; } static void uvc_video_stats_start(struct uvc_streaming *stream) { memset(&stream->stats, 0, sizeof(stream->stats)); stream->stats.stream.min_sof = 2048; } static void uvc_video_stats_stop(struct uvc_streaming *stream) { stream->stats.stream.stop_ts = ktime_get(); } /* ------------------------------------------------------------------------ * Video codecs */ /* * Video payload decoding is handled by uvc_video_decode_start(), * uvc_video_decode_data() and uvc_video_decode_end(). * * uvc_video_decode_start is called with URB data at the start of a bulk or * isochronous payload. It processes header data and returns the header size * in bytes if successful. If an error occurs, it returns a negative error * code. The following error codes have special meanings. * * - EAGAIN informs the caller that the current video buffer should be marked * as done, and that the function should be called again with the same data * and a new video buffer. This is used when end of frame conditions can be * reliably detected at the beginning of the next frame only. * * If an error other than -EAGAIN is returned, the caller will drop the current * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be * made until the next payload. -ENODATA can be used to drop the current * payload if no other error code is appropriate. * * uvc_video_decode_data is called for every URB with URB data. It copies the * data to the video buffer. * * uvc_video_decode_end is called with header data at the end of a bulk or * isochronous payload. It performs any additional header data processing and * returns 0 or a negative error code if an error occurred. As header data have * already been processed by uvc_video_decode_start, this functions isn't * required to perform sanity checks a second time. * * For isochronous transfers where a payload is always transferred in a single * URB, the three functions will be called in a row. * * To let the decoder process header data and update its internal state even * when no video buffer is available, uvc_video_decode_start must be prepared * to be called with a NULL buf parameter. uvc_video_decode_data and * uvc_video_decode_end will never be called with a NULL buffer. */ static int uvc_video_decode_start(struct uvc_streaming *stream, struct uvc_buffer *buf, const u8 *data, int len) { u8 fid; /* * Sanity checks: * - packet must be at least 2 bytes long * - bHeaderLength value must be at least 2 bytes (see above) * - bHeaderLength value can't be larger than the packet size. */ if (len < 2 || data[0] < 2 || data[0] > len) { stream->stats.frame.nb_invalid++; return -EINVAL; } fid = data[1] & UVC_STREAM_FID; /* * Increase the sequence number regardless of any buffer states, so * that discontinuous sequence numbers always indicate lost frames. */ if (stream->last_fid != fid) { stream->sequence++; if (stream->sequence) uvc_video_stats_update(stream); } uvc_video_clock_decode(stream, buf, data, len); uvc_video_stats_decode(stream, data, len); /* * Store the payload FID bit and return immediately when the buffer is * NULL. */ if (buf == NULL) { stream->last_fid = fid; return -ENODATA; } /* Mark the buffer as bad if the error bit is set. */ if (data[1] & UVC_STREAM_ERR) { uvc_dbg(stream->dev, FRAME, "Marking buffer as bad (error bit set)\n"); buf->error = 1; } /* * Synchronize to the input stream by waiting for the FID bit to be * toggled when the buffer state is not UVC_BUF_STATE_ACTIVE. * stream->last_fid is initialized to -1, so the first isochronous * frame will always be in sync. * * If the device doesn't toggle the FID bit, invert stream->last_fid * when the EOF bit is set to force synchronisation on the next packet. */ if (buf->state != UVC_BUF_STATE_ACTIVE) { if (fid == stream->last_fid) { uvc_dbg(stream->dev, FRAME, "Dropping payload (out of sync)\n"); if ((stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) && (data[1] & UVC_STREAM_EOF)) stream->last_fid ^= UVC_STREAM_FID; return -ENODATA; } buf->buf.field = V4L2_FIELD_NONE; buf->buf.sequence = stream->sequence; buf->buf.vb2_buf.timestamp = ktime_to_ns(uvc_video_get_time()); /* TODO: Handle PTS and SCR. */ buf->state = UVC_BUF_STATE_ACTIVE; } /* * Mark the buffer as done if we're at the beginning of a new frame. * End of frame detection is better implemented by checking the EOF * bit (FID bit toggling is delayed by one frame compared to the EOF * bit), but some devices don't set the bit at end of frame (and the * last payload can be lost anyway). We thus must check if the FID has * been toggled. * * stream->last_fid is initialized to -1, so the first isochronous * frame will never trigger an end of frame detection. * * Empty buffers (bytesused == 0) don't trigger end of frame detection * as it doesn't make sense to return an empty buffer. This also * avoids detecting end of frame conditions at FID toggling if the * previous payload had the EOF bit set. */ if (fid != stream->last_fid && buf->bytesused != 0) { uvc_dbg(stream->dev, FRAME, "Frame complete (FID bit toggled)\n"); buf->state = UVC_BUF_STATE_READY; return -EAGAIN; } stream->last_fid = fid; return data[0]; } static inline enum dma_data_direction uvc_stream_dir( struct uvc_streaming *stream) { if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) return DMA_FROM_DEVICE; else return DMA_TO_DEVICE; } static inline struct device *uvc_stream_to_dmadev(struct uvc_streaming *stream) { return bus_to_hcd(stream->dev->udev->bus)->self.sysdev; } static int uvc_submit_urb(struct uvc_urb *uvc_urb, gfp_t mem_flags) { /* Sync DMA. */ dma_sync_sgtable_for_device(uvc_stream_to_dmadev(uvc_urb->stream), uvc_urb->sgt, uvc_stream_dir(uvc_urb->stream)); return usb_submit_urb(uvc_urb->urb, mem_flags); } /* * uvc_video_decode_data_work: Asynchronous memcpy processing * * Copy URB data to video buffers in process context, releasing buffer * references and requeuing the URB when done. */ static void uvc_video_copy_data_work(struct work_struct *work) { struct uvc_urb *uvc_urb = container_of(work, struct uvc_urb, work); unsigned int i; int ret; for (i = 0; i < uvc_urb->async_operations; i++) { struct uvc_copy_op *op = &uvc_urb->copy_operations[i]; memcpy(op->dst, op->src, op->len); /* Release reference taken on this buffer. */ uvc_queue_buffer_release(op->buf); } ret = uvc_submit_urb(uvc_urb, GFP_KERNEL); if (ret < 0) dev_err(&uvc_urb->stream->intf->dev, "Failed to resubmit video URB (%d).\n", ret); } static void uvc_video_decode_data(struct uvc_urb *uvc_urb, struct uvc_buffer *buf, const u8 *data, int len) { unsigned int active_op = uvc_urb->async_operations; struct uvc_copy_op *op = &uvc_urb->copy_operations[active_op]; unsigned int maxlen; if (len <= 0) return; maxlen = buf->length - buf->bytesused; /* Take a buffer reference for async work. */ kref_get(&buf->ref); op->buf = buf; op->src = data; op->dst = buf->mem + buf->bytesused; op->len = min_t(unsigned int, len, maxlen); buf->bytesused += op->len; /* Complete the current frame if the buffer size was exceeded. */ if (len > maxlen) { uvc_dbg(uvc_urb->stream->dev, FRAME, "Frame complete (overflow)\n"); buf->error = 1; buf->state = UVC_BUF_STATE_READY; } uvc_urb->async_operations++; } static void uvc_video_decode_end(struct uvc_streaming *stream, struct uvc_buffer *buf, const u8 *data, int len) { /* Mark the buffer as done if the EOF marker is set. */ if (data[1] & UVC_STREAM_EOF && buf->bytesused != 0) { uvc_dbg(stream->dev, FRAME, "Frame complete (EOF found)\n"); if (data[0] == len) uvc_dbg(stream->dev, FRAME, "EOF in empty payload\n"); buf->state = UVC_BUF_STATE_READY; if (stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) stream->last_fid ^= UVC_STREAM_FID; } } /* * Video payload encoding is handled by uvc_video_encode_header() and * uvc_video_encode_data(). Only bulk transfers are currently supported. * * uvc_video_encode_header is called at the start of a payload. It adds header * data to the transfer buffer and returns the header size. As the only known * UVC output device transfers a whole frame in a single payload, the EOF bit * is always set in the header. * * uvc_video_encode_data is called for every URB and copies the data from the * video buffer to the transfer buffer. */ static int uvc_video_encode_header(struct uvc_streaming *stream, struct uvc_buffer *buf, u8 *data, int len) { data[0] = 2; /* Header length */ data[1] = UVC_STREAM_EOH | UVC_STREAM_EOF | (stream->last_fid & UVC_STREAM_FID); return 2; } static int uvc_video_encode_data(struct uvc_streaming *stream, struct uvc_buffer *buf, u8 *data, int len) { struct uvc_video_queue *queue = &stream->queue; unsigned int nbytes; void *mem; /* Copy video data to the URB buffer. */ mem = buf->mem + queue->buf_used; nbytes = min((unsigned int)len, buf->bytesused - queue->buf_used); nbytes = min(stream->bulk.max_payload_size - stream->bulk.payload_size, nbytes); memcpy(data, mem, nbytes); queue->buf_used += nbytes; return nbytes; } /* ------------------------------------------------------------------------ * Metadata */ /* * Additionally to the payload headers we also want to provide the user with USB * Frame Numbers and system time values. The resulting buffer is thus composed * of blocks, containing a 64-bit timestamp in nanoseconds, a 16-bit USB Frame * Number, and a copy of the payload header. * * Ideally we want to capture all payload headers for each frame. However, their * number is unknown and unbound. We thus drop headers that contain no vendor * data and that either contain no SCR value or an SCR value identical to the * previous header. */ static void uvc_video_decode_meta(struct uvc_streaming *stream, struct uvc_buffer *meta_buf, const u8 *mem, unsigned int length) { struct uvc_meta_buf *meta; size_t len_std = 2; bool has_pts, has_scr; unsigned long flags; unsigned int sof; ktime_t time; const u8 *scr; if (!meta_buf || length == 2) return; if (meta_buf->length - meta_buf->bytesused < length + sizeof(meta->ns) + sizeof(meta->sof)) { meta_buf->error = 1; return; } has_pts = mem[1] & UVC_STREAM_PTS; has_scr = mem[1] & UVC_STREAM_SCR; if (has_pts) { len_std += 4; scr = mem + 6; } else { scr = mem + 2; } if (has_scr) len_std += 6; if (stream->meta.format == V4L2_META_FMT_UVC) length = len_std; if (length == len_std && (!has_scr || !memcmp(scr, stream->clock.last_scr, 6))) return; meta = (struct uvc_meta_buf *)((u8 *)meta_buf->mem + meta_buf->bytesused); local_irq_save(flags); time = uvc_video_get_time(); sof = usb_get_current_frame_number(stream->dev->udev); local_irq_restore(flags); put_unaligned(ktime_to_ns(time), &meta->ns); put_unaligned(sof, &meta->sof); if (has_scr) memcpy(stream->clock.last_scr, scr, 6); meta->length = mem[0]; meta->flags = mem[1]; memcpy(meta->buf, &mem[2], length - 2); meta_buf->bytesused += length + sizeof(meta->ns) + sizeof(meta->sof); uvc_dbg(stream->dev, FRAME, "%s(): t-sys %lluns, SOF %u, len %u, flags 0x%x, PTS %u, STC %u frame SOF %u\n", __func__, ktime_to_ns(time), meta->sof, meta->length, meta->flags, has_pts ? *(u32 *)meta->buf : 0, has_scr ? *(u32 *)scr : 0, has_scr ? *(u32 *)(scr + 4) & 0x7ff : 0); } /* ------------------------------------------------------------------------ * URB handling */ /* * Set error flag for incomplete buffer. */ static void uvc_video_validate_buffer(const struct uvc_streaming *stream, struct uvc_buffer *buf) { if (stream->ctrl.dwMaxVideoFrameSize != buf->bytesused && !(stream->cur_format->flags & UVC_FMT_FLAG_COMPRESSED)) buf->error = 1; } /* * Completion handler for video URBs. */ static void uvc_video_next_buffers(struct uvc_streaming *stream, struct uvc_buffer **video_buf, struct uvc_buffer **meta_buf) { uvc_video_validate_buffer(stream, *video_buf); if (*meta_buf) { struct vb2_v4l2_buffer *vb2_meta = &(*meta_buf)->buf; const struct vb2_v4l2_buffer *vb2_video = &(*video_buf)->buf; vb2_meta->sequence = vb2_video->sequence; vb2_meta->field = vb2_video->field; vb2_meta->vb2_buf.timestamp = vb2_video->vb2_buf.timestamp; (*meta_buf)->state = UVC_BUF_STATE_READY; if (!(*meta_buf)->error) (*meta_buf)->error = (*video_buf)->error; *meta_buf = uvc_queue_next_buffer(&stream->meta.queue, *meta_buf); } *video_buf = uvc_queue_next_buffer(&stream->queue, *video_buf); } static void uvc_video_decode_isoc(struct uvc_urb *uvc_urb, struct uvc_buffer *buf, struct uvc_buffer *meta_buf) { struct urb *urb = uvc_urb->urb; struct uvc_streaming *stream = uvc_urb->stream; u8 *mem; int ret, i; for (i = 0; i < urb->number_of_packets; ++i) { if (urb->iso_frame_desc[i].status < 0) { uvc_dbg(stream->dev, FRAME, "USB isochronous frame lost (%d)\n", urb->iso_frame_desc[i].status); /* Mark the buffer as faulty. */ if (buf != NULL) buf->error = 1; continue; } /* Decode the payload header. */ mem = urb->transfer_buffer + urb->iso_frame_desc[i].offset; do { ret = uvc_video_decode_start(stream, buf, mem, urb->iso_frame_desc[i].actual_length); if (ret == -EAGAIN) uvc_video_next_buffers(stream, &buf, &meta_buf); } while (ret == -EAGAIN); if (ret < 0) continue; uvc_video_decode_meta(stream, meta_buf, mem, ret); /* Decode the payload data. */ uvc_video_decode_data(uvc_urb, buf, mem + ret, urb->iso_frame_desc[i].actual_length - ret); /* Process the header again. */ uvc_video_decode_end(stream, buf, mem, urb->iso_frame_desc[i].actual_length); if (buf->state == UVC_BUF_STATE_READY) uvc_video_next_buffers(stream, &buf, &meta_buf); } } static void uvc_video_decode_bulk(struct uvc_urb *uvc_urb, struct uvc_buffer *buf, struct uvc_buffer *meta_buf) { struct urb *urb = uvc_urb->urb; struct uvc_streaming *stream = uvc_urb->stream; u8 *mem; int len, ret; /* * Ignore ZLPs if they're not part of a frame, otherwise process them * to trigger the end of payload detection. */ if (urb->actual_length == 0 && stream->bulk.header_size == 0) return; mem = urb->transfer_buffer; len = urb->actual_length; stream->bulk.payload_size += len; /* * If the URB is the first of its payload, decode and save the * header. */ if (stream->bulk.header_size == 0 && !stream->bulk.skip_payload) { do { ret = uvc_video_decode_start(stream, buf, mem, len); if (ret == -EAGAIN) uvc_video_next_buffers(stream, &buf, &meta_buf); } while (ret == -EAGAIN); /* If an error occurred skip the rest of the payload. */ if (ret < 0 || buf == NULL) { stream->bulk.skip_payload = 1; } else { memcpy(stream->bulk.header, mem, ret); stream->bulk.header_size = ret; uvc_video_decode_meta(stream, meta_buf, mem, ret); mem += ret; len -= ret; } } /* * The buffer queue might have been cancelled while a bulk transfer * was in progress, so we can reach here with buf equal to NULL. Make * sure buf is never dereferenced if NULL. */ /* Prepare video data for processing. */ if (!stream->bulk.skip_payload && buf != NULL) uvc_video_decode_data(uvc_urb, buf, mem, len); /* * Detect the payload end by a URB smaller than the maximum size (or * a payload size equal to the maximum) and process the header again. */ if (urb->actual_length < urb->transfer_buffer_length || stream->bulk.payload_size >= stream->bulk.max_payload_size) { if (!stream->bulk.skip_payload && buf != NULL) { uvc_video_decode_end(stream, buf, stream->bulk.header, stream->bulk.payload_size); if (buf->state == UVC_BUF_STATE_READY) uvc_video_next_buffers(stream, &buf, &meta_buf); } stream->bulk.header_size = 0; stream->bulk.skip_payload = 0; stream->bulk.payload_size = 0; } } static void uvc_video_encode_bulk(struct uvc_urb *uvc_urb, struct uvc_buffer *buf, struct uvc_buffer *meta_buf) { struct urb *urb = uvc_urb->urb; struct uvc_streaming *stream = uvc_urb->stream; u8 *mem = urb->transfer_buffer; int len = stream->urb_size, ret; if (buf == NULL) { urb->transfer_buffer_length = 0; return; } /* If the URB is the first of its payload, add the header. */ if (stream->bulk.header_size == 0) { ret = uvc_video_encode_header(stream, buf, mem, len); stream->bulk.header_size = ret; stream->bulk.payload_size += ret; mem += ret; len -= ret; } /* Process video data. */ ret = uvc_video_encode_data(stream, buf, mem, len); stream->bulk.payload_size += ret; len -= ret; if (buf->bytesused == stream->queue.buf_used || stream->bulk.payload_size == stream->bulk.max_payload_size) { if (buf->bytesused == stream->queue.buf_used) { stream->queue.buf_used = 0; buf->state = UVC_BUF_STATE_READY; buf->buf.sequence = ++stream->sequence; uvc_queue_next_buffer(&stream->queue, buf); stream->last_fid ^= UVC_STREAM_FID; } stream->bulk.header_size = 0; stream->bulk.payload_size = 0; } urb->transfer_buffer_length = stream->urb_size - len; } static void uvc_video_complete(struct urb *urb) { struct uvc_urb *uvc_urb = urb->context; struct uvc_streaming *stream = uvc_urb->stream; struct uvc_video_queue *queue = &stream->queue; struct uvc_video_queue *qmeta = &stream->meta.queue; struct vb2_queue *vb2_qmeta = stream->meta.vdev.queue; struct uvc_buffer *buf = NULL; struct uvc_buffer *buf_meta = NULL; unsigned long flags; int ret; switch (urb->status) { case 0: break; default: dev_warn(&stream->intf->dev, "Non-zero status (%d) in video completion handler.\n", urb->status); fallthrough; case -ENOENT: /* usb_poison_urb() called. */ if (stream->frozen) return; fallthrough; case -ECONNRESET: /* usb_unlink_urb() called. */ case -ESHUTDOWN: /* The endpoint is being disabled. */ uvc_queue_cancel(queue, urb->status == -ESHUTDOWN); if (vb2_qmeta) uvc_queue_cancel(qmeta, urb->status == -ESHUTDOWN); return; } buf = uvc_queue_get_current_buffer(queue); if (vb2_qmeta) { spin_lock_irqsave(&qmeta->irqlock, flags); if (!list_empty(&qmeta->irqqueue)) buf_meta = list_first_entry(&qmeta->irqqueue, struct uvc_buffer, queue); spin_unlock_irqrestore(&qmeta->irqlock, flags); } /* Re-initialise the URB async work. */ uvc_urb->async_operations = 0; /* Sync DMA and invalidate vmap range. */ dma_sync_sgtable_for_cpu(uvc_stream_to_dmadev(uvc_urb->stream), uvc_urb->sgt, uvc_stream_dir(stream)); invalidate_kernel_vmap_range(uvc_urb->buffer, uvc_urb->stream->urb_size); /* * Process the URB headers, and optionally queue expensive memcpy tasks * to be deferred to a work queue. */ stream->decode(uvc_urb, buf, buf_meta); /* If no async work is needed, resubmit the URB immediately. */ if (!uvc_urb->async_operations) { ret = uvc_submit_urb(uvc_urb, GFP_ATOMIC); if (ret < 0) dev_err(&stream->intf->dev, "Failed to resubmit video URB (%d).\n", ret); return; } queue_work(stream->async_wq, &uvc_urb->work); } /* * Free transfer buffers. */ static void uvc_free_urb_buffers(struct uvc_streaming *stream) { struct device *dma_dev = uvc_stream_to_dmadev(stream); struct uvc_urb *uvc_urb; for_each_uvc_urb(uvc_urb, stream) { if (!uvc_urb->buffer) continue; dma_vunmap_noncontiguous(dma_dev, uvc_urb->buffer); dma_free_noncontiguous(dma_dev, stream->urb_size, uvc_urb->sgt, uvc_stream_dir(stream)); uvc_urb->buffer = NULL; uvc_urb->sgt = NULL; } stream->urb_size = 0; } static bool uvc_alloc_urb_buffer(struct uvc_streaming *stream, struct uvc_urb *uvc_urb, gfp_t gfp_flags) { struct device *dma_dev = uvc_stream_to_dmadev(stream); uvc_urb->sgt = dma_alloc_noncontiguous(dma_dev, stream->urb_size, uvc_stream_dir(stream), gfp_flags, 0); if (!uvc_urb->sgt) return false; uvc_urb->dma = uvc_urb->sgt->sgl->dma_address; uvc_urb->buffer = dma_vmap_noncontiguous(dma_dev, stream->urb_size, uvc_urb->sgt); if (!uvc_urb->buffer) { dma_free_noncontiguous(dma_dev, stream->urb_size, uvc_urb->sgt, uvc_stream_dir(stream)); uvc_urb->sgt = NULL; return false; } return true; } /* * Allocate transfer buffers. This function can be called with buffers * already allocated when resuming from suspend, in which case it will * return without touching the buffers. * * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the * system is too low on memory try successively smaller numbers of packets * until allocation succeeds. * * Return the number of allocated packets on success or 0 when out of memory. */ static int uvc_alloc_urb_buffers(struct uvc_streaming *stream, unsigned int size, unsigned int psize, gfp_t gfp_flags) { unsigned int npackets; unsigned int i; /* Buffers are already allocated, bail out. */ if (stream->urb_size) return stream->urb_size / psize; /* * Compute the number of packets. Bulk endpoints might transfer UVC * payloads across multiple URBs. */ npackets = DIV_ROUND_UP(size, psize); if (npackets > UVC_MAX_PACKETS) npackets = UVC_MAX_PACKETS; /* Retry allocations until one succeed. */ for (; npackets > 1; npackets /= 2) { stream->urb_size = psize * npackets; for (i = 0; i < UVC_URBS; ++i) { struct uvc_urb *uvc_urb = &stream->uvc_urb[i]; if (!uvc_alloc_urb_buffer(stream, uvc_urb, gfp_flags)) { uvc_free_urb_buffers(stream); break; } uvc_urb->stream = stream; } if (i == UVC_URBS) { uvc_dbg(stream->dev, VIDEO, "Allocated %u URB buffers of %ux%u bytes each\n", UVC_URBS, npackets, psize); return npackets; } } uvc_dbg(stream->dev, VIDEO, "Failed to allocate URB buffers (%u bytes per packet)\n", psize); return 0; } /* * Uninitialize isochronous/bulk URBs and free transfer buffers. */ static void uvc_video_stop_transfer(struct uvc_streaming *stream, int free_buffers) { struct uvc_urb *uvc_urb; uvc_video_stats_stop(stream); /* * We must poison the URBs rather than kill them to ensure that even * after the completion handler returns, any asynchronous workqueues * will be prevented from resubmitting the URBs. */ for_each_uvc_urb(uvc_urb, stream) usb_poison_urb(uvc_urb->urb); flush_workqueue(stream->async_wq); for_each_uvc_urb(uvc_urb, stream) { usb_free_urb(uvc_urb->urb); uvc_urb->urb = NULL; } if (free_buffers) uvc_free_urb_buffers(stream); } /* * Compute the maximum number of bytes per interval for an endpoint. */ u16 uvc_endpoint_max_bpi(struct usb_device *dev, struct usb_host_endpoint *ep) { u16 psize; switch (dev->speed) { case USB_SPEED_SUPER: case USB_SPEED_SUPER_PLUS: return le16_to_cpu(ep->ss_ep_comp.wBytesPerInterval); default: psize = usb_endpoint_maxp(&ep->desc); psize *= usb_endpoint_maxp_mult(&ep->desc); return psize; } } /* * Initialize isochronous URBs and allocate transfer buffers. The packet size * is given by the endpoint. */ static int uvc_init_video_isoc(struct uvc_streaming *stream, struct usb_host_endpoint *ep, gfp_t gfp_flags) { struct urb *urb; struct uvc_urb *uvc_urb; unsigned int npackets, i; u16 psize; u32 size; psize = uvc_endpoint_max_bpi(stream->dev->udev, ep); size = stream->ctrl.dwMaxVideoFrameSize; npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags); if (npackets == 0) return -ENOMEM; size = npackets * psize; for_each_uvc_urb(uvc_urb, stream) { urb = usb_alloc_urb(npackets, gfp_flags); if (urb == NULL) { uvc_video_stop_transfer(stream, 1); return -ENOMEM; } urb->dev = stream->dev->udev; urb->context = uvc_urb; urb->pipe = usb_rcvisocpipe(stream->dev->udev, ep->desc.bEndpointAddress); urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->transfer_dma = uvc_urb->dma; urb->interval = ep->desc.bInterval; urb->transfer_buffer = uvc_urb->buffer; urb->complete = uvc_video_complete; urb->number_of_packets = npackets; urb->transfer_buffer_length = size; for (i = 0; i < npackets; ++i) { urb->iso_frame_desc[i].offset = i * psize; urb->iso_frame_desc[i].length = psize; } uvc_urb->urb = urb; } return 0; } /* * Initialize bulk URBs and allocate transfer buffers. The packet size is * given by the endpoint. */ static int uvc_init_video_bulk(struct uvc_streaming *stream, struct usb_host_endpoint *ep, gfp_t gfp_flags) { struct urb *urb; struct uvc_urb *uvc_urb; unsigned int npackets, pipe; u16 psize; u32 size; psize = usb_endpoint_maxp(&ep->desc); size = stream->ctrl.dwMaxPayloadTransferSize; stream->bulk.max_payload_size = size; npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags); if (npackets == 0) return -ENOMEM; size = npackets * psize; if (usb_endpoint_dir_in(&ep->desc)) pipe = usb_rcvbulkpipe(stream->dev->udev, ep->desc.bEndpointAddress); else pipe = usb_sndbulkpipe(stream->dev->udev, ep->desc.bEndpointAddress); if (stream->type == V4L2_BUF_TYPE_VIDEO_OUTPUT) size = 0; for_each_uvc_urb(uvc_urb, stream) { urb = usb_alloc_urb(0, gfp_flags); if (urb == NULL) { uvc_video_stop_transfer(stream, 1); return -ENOMEM; } usb_fill_bulk_urb(urb, stream->dev->udev, pipe, uvc_urb->buffer, size, uvc_video_complete, uvc_urb); urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; urb->transfer_dma = uvc_urb->dma; uvc_urb->urb = urb; } return 0; } /* * Initialize isochronous/bulk URBs and allocate transfer buffers. */ static int uvc_video_start_transfer(struct uvc_streaming *stream, gfp_t gfp_flags) { struct usb_interface *intf = stream->intf; struct usb_host_endpoint *ep; struct uvc_urb *uvc_urb; unsigned int i; int ret; stream->sequence = -1; stream->last_fid = -1; stream->bulk.header_size = 0; stream->bulk.skip_payload = 0; stream->bulk.payload_size = 0; uvc_video_stats_start(stream); if (intf->num_altsetting > 1) { struct usb_host_endpoint *best_ep = NULL; unsigned int best_psize = UINT_MAX; unsigned int bandwidth; unsigned int altsetting; int intfnum = stream->intfnum; /* Isochronous endpoint, select the alternate setting. */ bandwidth = stream->ctrl.dwMaxPayloadTransferSize; if (bandwidth == 0) { uvc_dbg(stream->dev, VIDEO, "Device requested null bandwidth, defaulting to lowest\n"); bandwidth = 1; } else { uvc_dbg(stream->dev, VIDEO, "Device requested %u B/frame bandwidth\n", bandwidth); } for (i = 0; i < intf->num_altsetting; ++i) { struct usb_host_interface *alts; unsigned int psize; alts = &intf->altsetting[i]; ep = uvc_find_endpoint(alts, stream->header.bEndpointAddress); if (ep == NULL) continue; /* Check if the bandwidth is high enough. */ psize = uvc_endpoint_max_bpi(stream->dev->udev, ep); if (psize >= bandwidth && psize <= best_psize) { altsetting = alts->desc.bAlternateSetting; best_psize = psize; best_ep = ep; } } if (best_ep == NULL) { uvc_dbg(stream->dev, VIDEO, "No fast enough alt setting for requested bandwidth\n"); return -EIO; } uvc_dbg(stream->dev, VIDEO, "Selecting alternate setting %u (%u B/frame bandwidth)\n", altsetting, best_psize); /* * Some devices, namely the Logitech C910 and B910, are unable * to recover from a USB autosuspend, unless the alternate * setting of the streaming interface is toggled. */ if (stream->dev->quirks & UVC_QUIRK_WAKE_AUTOSUSPEND) { usb_set_interface(stream->dev->udev, intfnum, altsetting); usb_set_interface(stream->dev->udev, intfnum, 0); } ret = usb_set_interface(stream->dev->udev, intfnum, altsetting); if (ret < 0) return ret; ret = uvc_init_video_isoc(stream, best_ep, gfp_flags); } else { /* Bulk endpoint, proceed to URB initialization. */ ep = uvc_find_endpoint(&intf->altsetting[0], stream->header.bEndpointAddress); if (ep == NULL) return -EIO; /* Reject broken descriptors. */ if (usb_endpoint_maxp(&ep->desc) == 0) return -EIO; ret = uvc_init_video_bulk(stream, ep, gfp_flags); } if (ret < 0) return ret; /* Submit the URBs. */ for_each_uvc_urb(uvc_urb, stream) { ret = uvc_submit_urb(uvc_urb, gfp_flags); if (ret < 0) { dev_err(&stream->intf->dev, "Failed to submit URB %u (%d).\n", uvc_urb_index(uvc_urb), ret); uvc_video_stop_transfer(stream, 1); return ret; } } /* * The Logitech C920 temporarily forgets that it should not be adjusting * Exposure Absolute during init so restore controls to stored values. */ if (stream->dev->quirks & UVC_QUIRK_RESTORE_CTRLS_ON_INIT) uvc_ctrl_restore_values(stream->dev); return 0; } /* -------------------------------------------------------------------------- * Suspend/resume */ /* * Stop streaming without disabling the video queue. * * To let userspace applications resume without trouble, we must not touch the * video buffers in any way. We mark the device as frozen to make sure the URB * completion handler won't try to cancel the queue when we kill the URBs. */ int uvc_video_suspend(struct uvc_streaming *stream) { if (!uvc_queue_streaming(&stream->queue)) return 0; stream->frozen = 1; uvc_video_stop_transfer(stream, 0); usb_set_interface(stream->dev->udev, stream->intfnum, 0); return 0; } /* * Reconfigure the video interface and restart streaming if it was enabled * before suspend. * * If an error occurs, disable the video queue. This will wake all pending * buffers, making sure userspace applications are notified of the problem * instead of waiting forever. */ int uvc_video_resume(struct uvc_streaming *stream, int reset) { int ret; /* * If the bus has been reset on resume, set the alternate setting to 0. * This should be the default value, but some devices crash or otherwise * misbehave if they don't receive a SET_INTERFACE request before any * other video control request. */ if (reset) usb_set_interface(stream->dev->udev, stream->intfnum, 0); stream->frozen = 0; uvc_video_clock_reset(stream); if (!uvc_queue_streaming(&stream->queue)) return 0; ret = uvc_commit_video(stream, &stream->ctrl); if (ret < 0) return ret; return uvc_video_start_transfer(stream, GFP_NOIO); } /* ------------------------------------------------------------------------ * Video device */ /* * Initialize the UVC video device by switching to alternate setting 0 and * retrieve the default format. * * Some cameras (namely the Fuji Finepix) set the format and frame * indexes to zero. The UVC standard doesn't clearly make this a spec * violation, so try to silently fix the values if possible. * * This function is called before registering the device with V4L. */ int uvc_video_init(struct uvc_streaming *stream) { struct uvc_streaming_control *probe = &stream->ctrl; const struct uvc_format *format = NULL; const struct uvc_frame *frame = NULL; struct uvc_urb *uvc_urb; unsigned int i; int ret; if (stream->nformats == 0) { dev_info(&stream->intf->dev, "No supported video formats found.\n"); return -EINVAL; } atomic_set(&stream->active, 0); /* * Alternate setting 0 should be the default, yet the XBox Live Vision * Cam (and possibly other devices) crash or otherwise misbehave if * they don't receive a SET_INTERFACE request before any other video * control request. */ usb_set_interface(stream->dev->udev, stream->intfnum, 0); /* * Set the streaming probe control with default streaming parameters * retrieved from the device. Webcams that don't support GET_DEF * requests on the probe control will just keep their current streaming * parameters. */ if (uvc_get_video_ctrl(stream, probe, 1, UVC_GET_DEF) == 0) uvc_set_video_ctrl(stream, probe, 1); /* * Initialize the streaming parameters with the probe control current * value. This makes sure SET_CUR requests on the streaming commit * control will always use values retrieved from a successful GET_CUR * request on the probe control, as required by the UVC specification. */ ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR); /* * Elgato Cam Link 4k can be in a stalled state if the resolution of * the external source has changed while the firmware initializes. * Once in this state, the device is useless until it receives a * USB reset. It has even been observed that the stalled state will * continue even after unplugging the device. */ if (ret == -EPROTO && usb_match_one_id(stream->dev->intf, &elgato_cam_link_4k)) { dev_err(&stream->intf->dev, "Elgato Cam Link 4K firmware crash detected\n"); dev_err(&stream->intf->dev, "Resetting the device, unplug and replug to recover\n"); usb_reset_device(stream->dev->udev); } if (ret < 0) return ret; /* * Check if the default format descriptor exists. Use the first * available format otherwise. */ for (i = stream->nformats; i > 0; --i) { format = &stream->formats[i-1]; if (format->index == probe->bFormatIndex) break; } if (format->nframes == 0) { dev_info(&stream->intf->dev, "No frame descriptor found for the default format.\n"); return -EINVAL; } /* * Zero bFrameIndex might be correct. Stream-based formats (including * MPEG-2 TS and DV) do not support frames but have a dummy frame * descriptor with bFrameIndex set to zero. If the default frame * descriptor is not found, use the first available frame. */ for (i = format->nframes; i > 0; --i) { frame = &format->frames[i-1]; if (frame->bFrameIndex == probe->bFrameIndex) break; } probe->bFormatIndex = format->index; probe->bFrameIndex = frame->bFrameIndex; stream->def_format = format; stream->cur_format = format; stream->cur_frame = frame; /* Select the video decoding function */ if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) { if (stream->dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT) stream->decode = uvc_video_decode_isight; else if (stream->intf->num_altsetting > 1) stream->decode = uvc_video_decode_isoc; else stream->decode = uvc_video_decode_bulk; } else { if (stream->intf->num_altsetting == 1) stream->decode = uvc_video_encode_bulk; else { dev_info(&stream->intf->dev, "Isochronous endpoints are not supported for video output devices.\n"); return -EINVAL; } } /* Prepare asynchronous work items. */ for_each_uvc_urb(uvc_urb, stream) INIT_WORK(&uvc_urb->work, uvc_video_copy_data_work); return 0; } int uvc_video_start_streaming(struct uvc_streaming *stream) { int ret; ret = uvc_video_clock_init(stream); if (ret < 0) return ret; /* Commit the streaming parameters. */ ret = uvc_commit_video(stream, &stream->ctrl); if (ret < 0) goto error_commit; ret = uvc_video_start_transfer(stream, GFP_KERNEL); if (ret < 0) goto error_video; return 0; error_video: usb_set_interface(stream->dev->udev, stream->intfnum, 0); error_commit: uvc_video_clock_cleanup(stream); return ret; } void uvc_video_stop_streaming(struct uvc_streaming *stream) { uvc_video_stop_transfer(stream, 1); if (stream->intf->num_altsetting > 1) { usb_set_interface(stream->dev->udev, stream->intfnum, 0); } else { /* * UVC doesn't specify how to inform a bulk-based device * when the video stream is stopped. Windows sends a * CLEAR_FEATURE(HALT) request to the video streaming * bulk endpoint, mimic the same behaviour. */ unsigned int epnum = stream->header.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK; unsigned int dir = stream->header.bEndpointAddress & USB_ENDPOINT_DIR_MASK; unsigned int pipe; pipe = usb_sndbulkpipe(stream->dev->udev, epnum) | dir; usb_clear_halt(stream->dev->udev, pipe); } uvc_video_clock_cleanup(stream); }
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