V4L2攝像頭驅動移植
攝像頭驅動原始碼路徑:/drivers/media/video/uvc/uvc_v4l2.c
配置攝像v4l2驅動
make menuconfigDevice Drivers --->
<*> Multimedia support --->
<*> Video For Linux
[*] Video capture adapters --->
[*] V4L USB devices --->
<*> USB Video Class (UVC)
一般都符合UVC規範,不用修改原始碼,除非是自己定製的攝像頭驅動,自己購買cmos攝像頭,然後加上dsp處理圖片,壓縮成MJPEG格式,為了讓視訊更加流暢,這也只需要修改很小部分的程式碼。
自己寫V4L2驅動:myuvc.c
#include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> #include <linux/usb.h> #include <linux/videodev2.h> #include <linux/vmalloc.h> #include <linux/wait.h> #include <linux/mm.h> #include <asm/atomic.h> #include <asm/unaligned.h> #include <media/v4l2-common.h> #include <media/v4l2-ioctl.h> #include <media/videobuf-core.h> #include "uvcvideo.h" /* 參考 drivers/media/video/uvc */ #define MYUVC_URBS 5 /* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */ #define UVC_STREAM_EOH (1 << 7) #define UVC_STREAM_ERR (1 << 6) #define UVC_STREAM_STI (1 << 5) #define UVC_STREAM_RES (1 << 4) #define UVC_STREAM_SCR (1 << 3) #define UVC_STREAM_PTS (1 << 2) #define UVC_STREAM_EOF (1 << 1) #define UVC_STREAM_FID (1 << 0) struct myuvc_streaming_control { __u16 bmHint; __u8 bFormatIndex; __u8 bFrameIndex; __u32 dwFrameInterval; __u16 wKeyFrameRate; __u16 wPFrameRate; __u16 wCompQuality; __u16 wCompWindowSize; __u16 wDelay; __u32 dwMaxVideoFrameSize; __u32 dwMaxPayloadTransferSize; __u32 dwClockFrequency; __u8 bmFramingInfo; __u8 bPreferedVersion; __u8 bMinVersion; __u8 bMaxVersion; }; struct frame_desc { int width; int height; }; /* 參考uvc_video_queue定義一些結構體 */ struct myuvc_buffer { struct v4l2_buffer buf; int state; int vma_use_count; /* 表示是否已經被mmap */ wait_queue_head_t wait; /* APP要讀某個緩衝區,如果無資料,在此休眠 */ struct list_head stream; struct list_head irq; }; struct myuvc_queue { void *mem; int count; int buf_size; struct myuvc_buffer buffer[32]; struct urb *urb[32]; char *urb_buffer[32]; dma_addr_t urb_dma[32]; unsigned int urb_size; struct list_head mainqueue; /* 供APP消費用 */ struct list_head irqqueue; /* 供底層驅動生產用 */ }; static struct myuvc_queue myuvc_queue; static struct video_device *myuvc_vdev; static struct usb_device *myuvc_udev; static int myuvc_bEndpointAddress = 0x81; static int myuvc_streaming_intf; static int myuvc_control_intf; static int myuvc_streaming_bAlternateSetting = 8; static struct v4l2_format myuvc_format; static struct frame_desc frames[] = {{640, 480}, {352, 288}, {320, 240}, {176, 144}, {160, 120}}; static int frame_idx = 1; static int bBitsPerPixel = 16; /* lsusb -v -d 0x1e4e: "bBitsPerPixel" */ static int uvc_version = 0x0100; /* lsusb -v -d 0x1e4e: bcdUVC */ static int wMaxPacketSize = 1024; static int ProcessingUnitID = 3; static struct myuvc_streaming_control myuvc_params; /* A2 參考 uvc_v4l2_do_ioctl */ static int myuvc_vidioc_querycap(struct file *file, void *priv, struct v4l2_capability *cap) { memset(cap, 0, sizeof *cap); strcpy(cap->driver, "myuvc"); strcpy(cap->card, "myuvc"); cap->version = 1; cap->capabilities = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING; return 0; } /* A3 列舉支援哪種格式 * 參考: uvc_fmts 陣列 */ static int myuvc_vidioc_enum_fmt_vid_cap(struct file *file, void *priv, struct v4l2_fmtdesc *f) { /* 人工檢視描述符可知我們用的攝像頭只支援1種格式 */ if (f->index >= 1) return -EINVAL; /* 支援什麼格式呢? * 檢視VideoStreaming Interface的描述符, * 得到GUID為"59 55 59 32 00 00 10 00 80 00 00 aa 00 38 9b 71" */ strcpy(f->description, "4:2:2, packed, YUYV"); f->pixelformat = V4L2_PIX_FMT_YUYV; return 0; } /* A4 返回當前所使用的格式 */ static int myuvc_vidioc_g_fmt_vid_cap(struct file *file, void *priv, struct v4l2_format *f) { memcpy(f, &myuvc_format, sizeof(myuvc_format)); return (0); } /* A5 測試驅動程式是否支援某種格式, 強制設定該格式 * 參考: uvc_v4l2_try_format * myvivi_vidioc_try_fmt_vid_cap */ static int myuvc_vidioc_try_fmt_vid_cap(struct file *file, void *priv, struct v4l2_format *f) { if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) { return -EINVAL; } if (f->fmt.pix.pixelformat != V4L2_PIX_FMT_YUYV) return -EINVAL; /* 調整format的width, height, * 計算bytesperline, sizeimage */ /* 人工檢視描述符, 確定支援哪幾種解析度 */ f->fmt.pix.width = frames[frame_idx].width; f->fmt.pix.height = frames[frame_idx].height; f->fmt.pix.bytesperline = (f->fmt.pix.width * bBitsPerPixel) >> 3; f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline; return 0; } /* A6 參考 myvivi_vidioc_s_fmt_vid_cap */ static int myuvc_vidioc_s_fmt_vid_cap(struct file *file, void *priv, struct v4l2_format *f) { int ret = myuvc_vidioc_try_fmt_vid_cap(file, NULL, f); if (ret < 0) return ret; memcpy(&myuvc_format, f, sizeof(myuvc_format)); return 0; } static int myuvc_free_buffers(void) { if (myuvc_queue.mem) { vfree(myuvc_queue.mem); memset(&myuvc_queue, 0, sizeof(myuvc_queue)); myuvc_queue.mem = NULL; } return 0; } /* A7 APP呼叫該ioctl讓驅動程式分配若干個快取, APP將從這些快取中讀到視訊資料 * 參考: uvc_alloc_buffers */ static int myuvc_vidioc_reqbufs(struct file *file, void *priv, struct v4l2_requestbuffers *p) { int nbuffers = p->count; int bufsize = PAGE_ALIGN(myuvc_format.fmt.pix.sizeimage); unsigned int i; void *mem = NULL; int ret; if ((ret = myuvc_free_buffers()) < 0) goto done; /* Bail out if no buffers should be allocated. */ if (nbuffers == 0) goto done; /* Decrement the number of buffers until allocation succeeds. */ for (; nbuffers > 0; --nbuffers) { mem = vmalloc_32(nbuffers * bufsize); if (mem != NULL) break; } if (mem == NULL) { ret = -ENOMEM; goto done; } /* 這些快取是一次性作為一個整體來分配的 */ memset(&myuvc_queue, 0, sizeof(myuvc_queue)); INIT_LIST_HEAD(&myuvc_queue.mainqueue); INIT_LIST_HEAD(&myuvc_queue.irqqueue); for (i = 0; i < nbuffers; ++i) { myuvc_queue.buffer[i].buf.index = i; myuvc_queue.buffer[i].buf.m.offset = i * bufsize; myuvc_queue.buffer[i].buf.length = myuvc_format.fmt.pix.sizeimage; myuvc_queue.buffer[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; myuvc_queue.buffer[i].buf.sequence = 0; myuvc_queue.buffer[i].buf.field = V4L2_FIELD_NONE; myuvc_queue.buffer[i].buf.memory = V4L2_MEMORY_MMAP; myuvc_queue.buffer[i].buf.flags = 0; myuvc_queue.buffer[i].state = VIDEOBUF_IDLE; init_waitqueue_head(&myuvc_queue.buffer[i].wait); } myuvc_queue.mem = mem; myuvc_queue.count = nbuffers; myuvc_queue.buf_size = bufsize; ret = nbuffers; done: return ret; } /* A8 查詢快取狀態, 比如地址資訊(APP可以用mmap進行對映) * 參考 uvc_query_buffer */ static int myuvc_vidioc_querybuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf) { int ret = 0; if (v4l2_buf->index >= myuvc_queue.count) { ret = -EINVAL; goto done; } memcpy(v4l2_buf, &myuvc_queue.buffer[v4l2_buf->index].buf, sizeof(*v4l2_buf)); /* 更新flags */ if (myuvc_queue.buffer[v4l2_buf->index].vma_use_count) v4l2_buf->flags |= V4L2_BUF_FLAG_MAPPED; switch (myuvc_queue.buffer[v4l2_buf->index].state) { case VIDEOBUF_ERROR: case VIDEOBUF_DONE: v4l2_buf->flags |= V4L2_BUF_FLAG_DONE; break; case VIDEOBUF_QUEUED: case VIDEOBUF_ACTIVE: v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED; break; case VIDEOBUF_IDLE: default: break; } done: return ret; } /* A10 把緩衝區放入佇列, 底層的硬體操作函式將會把資料放入這個佇列的快取 * 參考: uvc_queue_buffer */ static int myuvc_vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf) { struct myuvc_buffer *buf; /* 0. APP傳入的v4l2_buf可能有問題, 要做判斷 */ if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE || v4l2_buf->memory != V4L2_MEMORY_MMAP) { return -EINVAL; } if (v4l2_buf->index >= myuvc_queue.count) { return -EINVAL; } buf = &myuvc_queue.buffer[v4l2_buf->index]; if (buf->state != VIDEOBUF_IDLE) { return -EINVAL; } /* 1. 修改狀態 */ buf->state = VIDEOBUF_QUEUED; buf->buf.bytesused = 0; /* 2. 放入2個佇列 */ /* 佇列1: 供APP使用 * 當緩衝區沒有資料時,放入mainqueue佇列 * 當緩衝區有資料時, APP從mainqueue佇列中取出 */ list_add_tail(&buf->stream, &myuvc_queue.mainqueue); /* 佇列2: 供產生資料的函式使用 * 當採集到資料時,從irqqueue佇列中取出第1個緩衝區,存入資料 */ list_add_tail(&buf->irq, &myuvc_queue.irqqueue); return 0; } static void myuvc_print_streaming_params(struct myuvc_streaming_control *ctrl) { printk("video params:\n"); printk("bmHint = %d\n", ctrl->bmHint); printk("bFormatIndex = %d\n", ctrl->bFormatIndex); printk("bFrameIndex = %d\n", ctrl->bFrameIndex); printk("dwFrameInterval = %d\n", ctrl->dwFrameInterval); printk("wKeyFrameRate = %d\n", ctrl->wKeyFrameRate); printk("wPFrameRate = %d\n", ctrl->wPFrameRate); printk("wCompQuality = %d\n", ctrl->wCompQuality); printk("wCompWindowSize = %d\n", ctrl->wCompWindowSize); printk("wDelay = %d\n", ctrl->wDelay); printk("dwMaxVideoFrameSize = %d\n", ctrl->dwMaxVideoFrameSize); printk("dwMaxPayloadTransferSize = %d\n", ctrl->dwMaxPayloadTransferSize); printk("dwClockFrequency = %d\n", ctrl->dwClockFrequency); printk("bmFramingInfo = %d\n", ctrl->bmFramingInfo); printk("bPreferedVersion = %d\n", ctrl->bPreferedVersion); printk("bMinVersion = %d\n", ctrl->bMinVersion); printk("bMinVersion = %d\n", ctrl->bMinVersion); } /* 參考: uvc_get_video_ctrl (ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR)) static int uvc_get_video_ctrl(struct uvc_video_device *video, struct uvc_streaming_control *ctrl, int probe, __u8 query) */ static int myuvc_get_streaming_params(struct myuvc_streaming_control *ctrl) { __u8 *data; __u16 size; int ret; __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; size = uvc_version >= 0x0110 ? 34 : 26; data = kmalloc(size, GFP_KERNEL); if (data == NULL) return -ENOMEM; pipe = (GET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0) : usb_sndctrlpipe(myuvc_udev, 0); type |= (GET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT; ret = usb_control_msg(myuvc_udev, pipe, GET_CUR, type, VS_PROBE_CONTROL << 8, 0 << 8 | myuvc_streaming_intf, data, size, 5000); if (ret < 0) goto done; 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 = video->dev->clock_frequency; ctrl->bmFramingInfo = 0; ctrl->bPreferedVersion = 0; ctrl->bMinVersion = 0; ctrl->bMaxVersion = 0; } done: kfree(data); return (ret < 0) ? ret : 0; } /* 參考: uvc_v4l2_try_format ∕uvc_probe_video * uvc_set_video_ctrl(video, probe, 1) */ static int myuvc_try_streaming_params(struct myuvc_streaming_control *ctrl) { __u8 *data; __u16 size; int ret; __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; memset(ctrl, 0, sizeof *ctrl); ctrl->bmHint = 1; /* dwFrameInterval */ ctrl->bFormatIndex = 1; ctrl->bFrameIndex = frame_idx + 1; ctrl->dwFrameInterval = 333333; size = uvc_version >= 0x0110 ? 34 : 26; 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; } pipe = (SET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0) : usb_sndctrlpipe(myuvc_udev, 0); type |= (SET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT; ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, VS_PROBE_CONTROL << 8, 0 << 8 | myuvc_streaming_intf, data, size, 5000); kfree(data); return (ret < 0) ? ret : 0; } /* 參考: uvc_v4l2_try_format ∕uvc_probe_video * uvc_set_video_ctrl(video, probe, 1) */ static int myuvc_set_streaming_params(struct myuvc_streaming_control *ctrl) { __u8 *data; __u16 size; int ret; __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; size = uvc_version >= 0x0110 ? 34 : 26; 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; } pipe = (SET_CUR & 0x80) ? usb_rcvctrlpipe(myuvc_udev, 0) : usb_sndctrlpipe(myuvc_udev, 0); type |= (SET_CUR & 0x80) ? USB_DIR_IN : USB_DIR_OUT; ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, VS_COMMIT_CONTROL << 8, 0 << 8 | myuvc_streaming_intf, data, size, 5000); kfree(data); return (ret < 0) ? ret : 0; } static void myuvc_uninit_urbs(void) { int i; for (i = 0; i < MYUVC_URBS; ++i) { if (myuvc_queue.urb_buffer[i]) { usb_buffer_free(myuvc_udev, myuvc_queue.urb_size, myuvc_queue.urb_buffer[i], myuvc_queue.urb_dma[i]); myuvc_queue.urb_buffer[i] = NULL; } if (myuvc_queue.urb[i]) { usb_free_urb(myuvc_queue.urb[i]); myuvc_queue.urb[i] = NULL; } } } /* 參考: uvc_video_complete / uvc_video_decode_isoc */ static void myuvc_video_complete(struct urb *urb) { u8 *src; u8 *dest; int ret, i; int len; int maxlen; int nbytes; struct myuvc_buffer *buf; switch (urb->status) { case 0: break; default: printk("Non-zero status (%d) in video " "completion handler.\n", urb->status); return; } /* 從irqqueue佇列中取出第1個緩衝區 */ if (!list_empty(&myuvc_queue.irqqueue)) { buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq); for (i = 0; i < urb->number_of_packets; ++i) { if (urb->iso_frame_desc[i].status < 0) { printk("USB isochronous frame " "lost (%d).\n", urb->iso_frame_desc[i].status); continue; } src = urb->transfer_buffer + urb->iso_frame_desc[i].offset; dest = myuvc_queue.mem + buf->buf.m.offset + buf->buf.bytesused; len = urb->iso_frame_desc[i].actual_length; /* 判斷資料是否有效 */ /* URB資料含義: * data[0] : 頭部長度 * data[1] : 錯誤狀態 */ if (len < 2 || src[0] < 2 || src[0] > len) continue; /* Skip payloads marked with the error bit ("error frames"). */ if (src[1] & UVC_STREAM_ERR) { printk("Dropping payload (error bit set).\n"); continue; } /* 除去頭部後的資料長度 */ len -= src[0]; /* 緩衝區最多還能存多少資料 */ maxlen = buf->buf.length - buf->buf.bytesused; nbytes = min(len, maxlen); /* 複製資料 */ memcpy(dest, src + src[0], nbytes); buf->buf.bytesused += nbytes; /* 判斷一幀資料是否已經全部接收到 */ if (len > maxlen) { buf->state = VIDEOBUF_DONE; } /* Mark the buffer as done if the EOF marker is set. */ if (src[1] & UVC_STREAM_EOF && buf->buf.bytesused != 0) { printk("Frame complete (EOF found).\n"); if (len == 0) printk("EOF in empty payload.\n"); buf->state = VIDEOBUF_DONE; } } /* 當接收完一幀資料, * 從irqqueue中刪除這個緩衝區 * 喚醒等待資料的程序 */ if (buf->state == VIDEOBUF_DONE || buf->state == VIDEOBUF_ERROR) { list_del(&buf->irq); wake_up(&buf->wait); } } /* 再次提交URB */ if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) { printk("Failed to resubmit video URB (%d).\n", ret); } } /* 參考: uvc_init_video_isoc */ static int myuvc_alloc_init_urbs(void) { u16 psize; u32 size; int npackets; int i; int j; struct urb *urb; psize = wMaxPacketSize; /* 實時傳輸端點一次能傳輸的最大位元組數 */ size = myuvc_params.dwMaxVideoFrameSize; /* 一幀資料的最大長度 */ npackets = DIV_ROUND_UP(size, psize); if (npackets > 32) npackets = 32; size = myuvc_queue.urb_size = psize * npackets; for (i = 0; i < MYUVC_URBS; ++i) { /* 1. 分配usb_buffers */ myuvc_queue.urb_buffer[i] = usb_buffer_alloc( myuvc_udev, size, GFP_KERNEL | __GFP_NOWARN, &myuvc_queue.urb_dma[i]); /* 2. 分配urb */ myuvc_queue.urb[i] = usb_alloc_urb(npackets, GFP_KERNEL); if (!myuvc_queue.urb_buffer[i] || !myuvc_queue.urb[i]) { myuvc_uninit_urbs(); return -ENOMEM; } } /* 3. 設定urb */ for (i = 0; i < MYUVC_URBS; ++i) { urb = myuvc_queue.urb[i]; urb->dev = myuvc_udev; urb->context = NULL; urb->pipe = usb_rcvisocpipe(myuvc_udev,myuvc_bEndpointAddress); urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->interval = 1; urb->transfer_buffer = myuvc_queue.urb_buffer[i]; urb->transfer_dma = myuvc_queue.urb_dma[i]; urb->complete = myuvc_video_complete; urb->number_of_packets = npackets; urb->transfer_buffer_length = size; for (j = 0; j < npackets; ++j) { urb->iso_frame_desc[j].offset = j * psize; urb->iso_frame_desc[j].length = psize; } } return 0; } /* A11 啟動傳輸 * 參考: uvc_video_enable(video, 1): * uvc_commit_video * uvc_init_video */ static int myuvc_vidioc_streamon(struct file *file, void *priv, enum v4l2_buf_type i) { int ret; /* 1. 向USB攝像頭設定引數: 比如使用哪個format, 使用這個format下的哪個frame(解析度) * 參考: uvc_set_video_ctrl / uvc_get_video_ctrl * 1.1 根據一個結構體uvc_streaming_control設定資料包: 可以手工設定,也可以讀出後再修改 * 1.2 呼叫usb_control_msg發出資料包 */ /* a. 測試引數 */ ret = myuvc_try_streaming_params(&myuvc_params); printk("myuvc_try_streaming_params ret = %d\n", ret); /* b. 取出引數 */ ret = myuvc_get_streaming_params(&myuvc_params); printk("myuvc_get_streaming_params ret = %d\n", ret); /* c. 設定引數 */ ret = myuvc_set_streaming_params(&myuvc_params); printk("myuvc_set_streaming_params ret = %d\n", ret); myuvc_print_streaming_params(&myuvc_params); /* d. 設定VideoStreaming Interface所使用的setting * d.1 從myuvc_params確定頻寬 * d.2 根據setting的endpoint能傳輸的wMaxPacketSize * 找到能滿足該頻寬的setting */ /* 手工確定: * bandwidth = myuvc_params.dwMaxPayloadTransferSize = 1024 * 觀察lsusb -v -d 0x1e4e:的結果: * wMaxPacketSize 0x0400 1x 1024 bytes * bAlternateSetting 8 */ usb_set_interface(myuvc_udev, myuvc_streaming_intf, myuvc_streaming_bAlternateSetting); /* 2. 分配設定URB */ ret = myuvc_alloc_init_urbs(); if (ret) printk("myuvc_alloc_init_urbs err : ret = %d\n", ret); /* 3. 提交URB以接收資料 */ for (i = 0; i < MYUVC_URBS; ++i) { if ((ret = usb_submit_urb(myuvc_queue.urb[i], GFP_KERNEL)) < 0) { printk("Failed to submit URB %u (%d).\n", i, ret); myuvc_uninit_urbs(); return ret; } } return 0; } /* A13 APP通過poll/select確定有資料後, 把快取從佇列中取出來 * 參考: uvc_dequeue_buffer */ static int myuvc_vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf) { /* APP發現數據就緒後, 從mainqueue裡取出這個buffer */ struct myuvc_buffer *buf; int ret = 0; if (list_empty(&myuvc_queue.mainqueue)) { ret = -EINVAL; goto done; } buf = list_first_entry(&myuvc_queue.mainqueue, struct myuvc_buffer, stream); switch (buf->state) { case VIDEOBUF_ERROR: ret = -EIO; case VIDEOBUF_DONE: buf->state = VIDEOBUF_IDLE; break; case VIDEOBUF_IDLE: case VIDEOBUF_QUEUED: case VIDEOBUF_ACTIVE: default: ret = -EINVAL; goto done; } list_del(&buf->stream); done: return ret; } /* * A14 之前已經通過mmap映射了快取, APP可以直接讀資料 * A15 再次呼叫myuvc_vidioc_qbuf把快取放入佇列 * A16 poll... */ /* A17 停止 * 參考 : uvc_video_enable(video, 0) */ static int myuvc_vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type t) { struct urb *urb; unsigned int i; /* 1. kill URB */ for (i = 0; i < MYUVC_URBS; ++i) { if ((urb = myuvc_queue.urb[i]) == NULL) continue; usb_kill_urb(urb); } /* 2. free URB */ myuvc_uninit_urbs(); /* 3. 設定VideoStreaming Interface為setting 0 */ usb_set_interface(myuvc_udev, myuvc_streaming_intf, 0); return 0; } /* Control handling */ /* Extract the bit string specified by mapping->offset and mapping->size * from the little-endian data stored at 'data' and return the result as * a signed 32bit integer. Sign extension will be performed if the mapping * references a signed data type. */ static __s32 myuvc_get_le_value(const __u8 *data) { int bits = 16; int offset = 0; __s32 value = 0; __u8 mask; data += offset / 8; offset &= 7; mask = ((1LL << bits) - 1) << offset; for (; bits > 0; data++) { __u8 byte = *data & mask; value |= offset > 0 ? (byte >> offset) : (byte << (-offset)); bits -= 8 - (offset > 0 ? offset : 0); offset -= 8; mask = (1 << bits) - 1; } /* Sign-extend the value if needed. */ value |= -(value & (1 << (16 - 1))); return value; } /* Set the bit string specified by mapping->offset and mapping->size * in the little-endian data stored at 'data' to the value 'value'. */ static void myuvc_set_le_value(__s32 value, __u8 *data) { int bits = 16; int offset = 0; __u8 mask; data += offset / 8; offset &= 7; for (; bits > 0; data++) { mask = ((1LL << bits) - 1) << offset; *data = (*data & ~mask) | ((value << offset) & mask); value >>= offset ? offset : 8; bits -= 8 - offset; offset = 0; } } /* 參考:uvc_query_v4l2_ctrl */ int myuvc_vidioc_queryctrl (struct file *file, void *fh, struct v4l2_queryctrl *ctrl) { __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; int ret; u8 data[2]; if (ctrl->id != V4L2_CID_BRIGHTNESS) return -EINVAL; memset(ctrl, 0, sizeof *ctrl); ctrl->id = V4L2_CID_BRIGHTNESS; ctrl->type = V4L2_CTRL_TYPE_INTEGER; strcpy(ctrl->name, "MyUVC_BRIGHTNESS"); ctrl->flags = 0; pipe = usb_rcvctrlpipe(myuvc_udev, 0); type |= USB_DIR_IN; /* 發起USB傳輸確定這些值 */ ret = usb_control_msg(myuvc_udev, pipe, GET_MIN, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; ctrl->minimum = myuvc_get_le_value(data); /* Note signedness */ ret = usb_control_msg(myuvc_udev, pipe, GET_MAX, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; ctrl->maximum = myuvc_get_le_value(data); /* Note signedness */ ret = usb_control_msg(myuvc_udev, pipe, GET_RES, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; ctrl->step = myuvc_get_le_value(data); /* Note signedness */ ret = usb_control_msg(myuvc_udev, pipe, GET_DEF, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; ctrl->default_value = myuvc_get_le_value(data); /* Note signedness */ printk("Brightness: min =%d, max = %d, step = %d, default = %d\n", ctrl->minimum, ctrl->maximum, ctrl->step, ctrl->default_value); return 0; } /* 參考 : uvc_ctrl_get */ int myuvc_vidioc_g_ctrl (struct file *file, void *fh, struct v4l2_control *ctrl) { __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; int ret; u8 data[2]; if (ctrl->id != V4L2_CID_BRIGHTNESS) return -EINVAL; pipe = usb_rcvctrlpipe(myuvc_udev, 0); type |= USB_DIR_IN; ret = usb_control_msg(myuvc_udev, pipe, GET_CUR, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; ctrl->value = myuvc_get_le_value(data); /* Note signedness */ return 0; } /* 參考: uvc_ctrl_set/uvc_ctrl_commit */ int myuvc_vidioc_s_ctrl (struct file *file, void *fh, struct v4l2_control *ctrl) { __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; unsigned int pipe; int ret; u8 data[2]; if (ctrl->id != V4L2_CID_BRIGHTNESS) return -EINVAL; myuvc_set_le_value(ctrl->value, data); pipe = usb_sndctrlpipe(myuvc_udev, 0); type |= USB_DIR_OUT; ret = usb_control_msg(myuvc_udev, pipe, SET_CUR, type, PU_BRIGHTNESS_CONTROL << 8, ProcessingUnitID << 8 | myuvc_control_intf, data, 2, 5000); if (ret != 2) return -EIO; return 0; } static const struct v4l2_ioctl_ops myuvc_ioctl_ops = { // 表示它是一個攝像頭裝置 .vidioc_querycap = myuvc_vidioc_querycap, /* 用於列舉、獲得、測試、設定攝像頭的資料的格式 */ .vidioc_enum_fmt_vid_cap = myuvc_vidioc_enum_fmt_vid_cap, .vidioc_g_fmt_vid_cap = myuvc_vidioc_g_fmt_vid_cap, .vidioc_try_fmt_vid_cap = myuvc_vidioc_try_fmt_vid_cap, .vidioc_s_fmt_vid_cap = myuvc_vidioc_s_fmt_vid_cap, /* 緩衝區操作: 申請/查詢/放入佇列/取出佇列 */ .vidioc_reqbufs = myuvc_vidioc_reqbufs, .vidioc_querybuf = myuvc_vidioc_querybuf, .vidioc_qbuf = myuvc_vidioc_qbuf, .vidioc_dqbuf = myuvc_vidioc_dqbuf, /* 查詢/獲得/設定屬性 */ .vidioc_queryctrl = myuvc_vidioc_queryctrl, .vidioc_g_ctrl = myuvc_vidioc_g_ctrl, .vidioc_s_ctrl = myuvc_vidioc_s_ctrl, // 啟動/停止 .vidioc_streamon = myuvc_vidioc_streamon, .vidioc_streamoff = myuvc_vidioc_streamoff, }; /* A1 */ static int myuvc_open(struct file *file) { return 0; } static void myuvc_vm_open(struct vm_area_struct *vma) { struct myuvc_buffer *buffer = vma->vm_private_data; buffer->vma_use_count++; } static void myuvc_vm_close(struct vm_area_struct *vma) { struct myuvc_buffer *buffer = vma->vm_private_data; buffer->vma_use_count--; } static struct vm_operations_struct myuvc_vm_ops = { .open = myuvc_vm_open, .close = myuvc_vm_close, }; /* A9 把快取對映到APP的空間,以後APP就可以直接操作這塊快取 * 參考: uvc_v4l2_mmap */ static int myuvc_mmap(struct file *file, struct vm_area_struct *vma) { struct myuvc_buffer *buffer; struct page *page; unsigned long addr, start, size; unsigned int i; int ret = 0; start = vma->vm_start; size = vma->vm_end - vma->vm_start; /* 應用程式呼叫mmap函式時, 會傳入offset引數 * 根據這個offset找出指定的緩衝區 */ for (i = 0; i < myuvc_queue.count; ++i) { buffer = &myuvc_queue.buffer[i]; if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) break; } if (i == myuvc_queue.count || size != myuvc_queue.buf_size) { ret = -EINVAL; goto done; } /* * VM_IO marks the area as being an mmaped region for I/O to a * device. It also prevents the region from being core dumped. */ vma->vm_flags |= VM_IO; /* 根據虛擬地址找到緩衝區對應的page構體 */ addr = (unsigned long)myuvc_queue.mem + buffer->buf.m.offset; while (size > 0) { page = vmalloc_to_page((void *)addr); /* 把page和APP傳入的虛擬地址掛構 */ if ((ret = vm_insert_page(vma, start, page)) < 0) goto done; start += PAGE_SIZE; addr += PAGE_SIZE; size -= PAGE_SIZE; } vma->vm_ops = &myuvc_vm_ops; vma->vm_private_data = buffer; myuvc_vm_open(vma); done: return ret; } /* A12 APP呼叫POLL/select來確定快取是否就緒(有資料) * 參考 : uvc_v4l2_poll */ static unsigned int myuvc_poll(struct file *file, struct poll_table_struct *wait) { struct myuvc_buffer *buf; unsigned int mask = 0; /* 從mainqueuq中取出第1個緩衝區 */ /*判斷它的狀態, 如果未就緒, 休眠 */ if (list_empty(&myuvc_queue.mainqueue)) { mask |= POLLERR; goto done; } buf = list_first_entry(&myuvc_queue.mainqueue, struct myuvc_buffer, stream); poll_wait(file, &buf->wait, wait); if (buf->state == VIDEOBUF_DONE || buf->state == VIDEOBUF_ERROR) mask |= POLLIN | POLLRDNORM; done: return mask; } /* A18 關閉 */ static int myuvc_close(struct file *file) { return 0; } static const struct v4l2_file_operations myuvc_fops = { .owner = THIS_MODULE, .open = myuvc_open, .release = myuvc_close, .mmap = myuvc_mmap, .ioctl = video_ioctl2, /* V4L2 ioctl handler */ .poll = myuvc_poll, }; static void myuvc_release(struct video_device *vdev) { } static int myuvc_probe(struct usb_interface *intf, const struct usb_device_id *id) { static int cnt = 0; struct usb_device *dev = interface_to_usbdev(intf); myuvc_udev = dev; printk("myuvc_probe : cnt = %d\n", cnt++); if (cnt == 1) { myuvc_control_intf = intf->cur_altsetting->desc.bInterfaceNumber; } else if (cnt == 2) { myuvc_streaming_intf = intf->cur_altsetting->desc.bInterfaceNumber; } if (cnt == 2) { /* 1. 分配一個video_device結構體 */ myuvc_vdev = video_device_alloc(); /* 2. 設定 */ /* 2.1 */ myuvc_vdev->release = myuvc_release; /* 2.2 */ myuvc_vdev->fops = &myuvc_fops; /* 2.3 */ myuvc_vdev->ioctl_ops = &myuvc_ioctl_ops; /* 3. 註冊 */ video_register_device(myuvc_vdev, VFL_TYPE_GRABBER, -1); } return 0; } static void myuvc_disconnect(struct usb_interface *intf) { static int cnt = 0; printk("myuvc_disconnect : cnt = %d\n", cnt++); if (cnt == 2) { video_unregister_device(myuvc_vdev); video_device_release(myuvc_vdev); } } static struct usb_device_id myuvc_ids[] = { /* Generic USB Video Class */ { USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, 0) }, /* VideoControl Interface */ { USB_INTERFACE_INFO(USB_CLASS_VIDEO, 2, 0) }, /* VideoStreaming Interface */ {} }; /* 1. 分配usb_driver */ /* 2. 設定 */ static struct usb_driver myuvc_driver = { .name = "myuvc", .probe = myuvc_probe, .disconnect = myuvc_disconnect, .id_table = myuvc_ids, }; static int myuvc_init(void) { /* 3. 註冊 */ usb_register(&myuvc_driver); return 0; } static void myuvc_exit(void) { usb_deregister(&myuvc_driver); } module_init(myuvc_init); module_exit(myuvc_exit); MODULE_LICENSE("GPL");
uvcvideo.h
#ifndef _USB_VIDEO_H_ #define _USB_VIDEO_H_ #include <linux/kernel.h> #include <linux/videodev2.h> /* * Dynamic controls */ /* Data types for UVC control data */ #define UVC_CTRL_DATA_TYPE_RAW 0 #define UVC_CTRL_DATA_TYPE_SIGNED 1 #define UVC_CTRL_DATA_TYPE_UNSIGNED 2 #define UVC_CTRL_DATA_TYPE_BOOLEAN 3 #define UVC_CTRL_DATA_TYPE_ENUM 4 #define UVC_CTRL_DATA_TYPE_BITMASK 5 /* Control flags */ #define UVC_CONTROL_SET_CUR (1 << 0) #define UVC_CONTROL_GET_CUR (1 << 1) #define UVC_CONTROL_GET_MIN (1 << 2) #define UVC_CONTROL_GET_MAX (1 << 3) #define UVC_CONTROL_GET_RES (1 << 4) #define UVC_CONTROL_GET_DEF (1 << 5) /* Control should be saved at suspend and restored at resume. */ #define UVC_CONTROL_RESTORE (1 << 6) /* Control can be updated by the camera. */ #define UVC_CONTROL_AUTO_UPDATE (1 << 7) #define UVC_CONTROL_GET_RANGE (UVC_CONTROL_GET_CUR | UVC_CONTROL_GET_MIN | \ UVC_CONTROL_GET_MAX | UVC_CONTROL_GET_RES | \ UVC_CONTROL_GET_DEF) struct uvc_xu_control_info { __u8 entity[16]; __u8 index; __u8 selector; __u16 size; __u32 flags; }; struct uvc_xu_control_mapping { __u32 id; __u8 name[32]; __u8 entity[16]; __u8 selector; __u8 size; __u8 offset; enum v4l2_ctrl_type v4l2_type; __u32 data_type; }; struct uvc_xu_control { __u8 unit; __u8 selector; __u16 size; __u8 __user *data; }; #define UVCIOC_CTRL_ADD _IOW('U', 1, struct uvc_xu_control_info) #define UVCIOC_CTRL_MAP _IOWR('U', 2, struct uvc_xu_control_mapping) #define UVCIOC_CTRL_GET _IOWR('U', 3, struct uvc_xu_control) #define UVCIOC_CTRL_SET _IOW('U', 4, struct uvc_xu_control) #ifdef __KERNEL__ #include <linux/poll.h> /* -------------------------------------------------------------------------- * UVC constants */ #define SC_UNDEFINED 0x00 #define SC_VIDEOCONTROL 0x01 #define SC_VIDEOSTREAMING 0x02 #define SC_VIDEO_INTERFACE_COLLECTION 0x03 #define PC_PROTOCOL_UNDEFINED 0x00 #define CS_UNDEFINED 0x20 #define CS_DEVICE 0x21 #define CS_CONFIGURATION 0x22 #define CS_STRING 0x23 #define CS_INTERFACE 0x24 #define CS_ENDPOINT 0x25 /* VideoControl class specific interface descriptor */ #define VC_DESCRIPTOR_UNDEFINED 0x00 #define VC_HEADER 0x01 #define VC_INPUT_TERMINAL 0x02 #define VC_OUTPUT_TERMINAL 0x03 #define VC_SELECTOR_UNIT 0x04 #define VC_PROCESSING_UNIT 0x05 #define VC_EXTENSION_UNIT 0x06 /* VideoStreaming class specific interface descriptor */ #define VS_UNDEFINED 0x00 #define VS_INPUT_HEADER 0x01 #define VS_OUTPUT_HEADER 0x02 #define VS_STILL_IMAGE_FRAME 0x03 #define VS_FORMAT_UNCOMPRESSED 0x04 #define VS_FRAME_UNCOMPRESSED 0x05 #define VS_FORMAT_MJPEG 0x06 #define VS_FRAME_MJPEG 0x07 #define VS_FORMAT_MPEG2TS 0x0a #define VS_FORMAT_DV 0x0c #define VS_COLORFORMAT 0x0d #define VS_FORMAT_FRAME_BASED 0x10 #define VS_FRAME_FRAME_BASED 0x11 #define VS_FORMAT_STREAM_BASED 0x12 /* Endpoint type */ #define EP_UNDEFINED 0x00 #define EP_GENERAL 0x01 #define EP_ENDPOINT 0x02 #define EP_INTERRUPT 0x03 /* Request codes */ #define RC_UNDEFINED 0x00 #define SET_CUR 0x01 #define GET_CUR 0x81 #define GET_MIN 0x82 #define GET_MAX 0x83 #define GET_RES 0x84 #define GET_LEN 0x85 #define GET_INFO 0x86 #define GET_DEF 0x87 /* VideoControl interface controls */ #define VC_CONTROL_UNDEFINED 0x00 #define VC_VIDEO_POWER_MODE_CONTROL 0x01 #define VC_REQUEST_ERROR_CODE_CONTROL 0x02 /* Terminal controls */ #define TE_CONTROL_UNDEFINED 0x00 /* Selector Unit controls */ #define SU_CONTROL_UNDEFINED 0x00 #define SU_INPUT_SELECT_CONTROL 0x01 /* Camera Terminal controls */ #define CT_CONTROL_UNDEFINED 0x00 #define CT_SCANNING_MODE_CONTROL 0x01 #define CT_AE_MODE_CONTROL 0x02 #define CT_AE_PRIORITY_CONTROL 0x03 #define CT_EXPOSURE_TIME_ABSOLUTE_CONTROL 0x04 #define CT_EXPOSURE_TIME_RELATIVE_CONTROL 0x05 #define CT_FOCUS_ABSOLUTE_CONTROL 0x06 #define CT_FOCUS_RELATIVE_CONTROL 0x07 #define CT_FOCUS_AUTO_CONTROL 0x08 #define CT_IRIS_ABSOLUTE_CONTROL 0x09 #define CT_IRIS_RELATIVE_CONTROL 0x0a #define CT_ZOOM_ABSOLUTE_CONTROL 0x0b #define CT_ZOOM_RELATIVE_CONTROL 0x0c #define CT_PANTILT_ABSOLUTE_CONTROL 0x0d #define CT_PANTILT_RELATIVE_CONTROL 0x0e #define CT_ROLL_ABSOLUTE_CONTROL 0x0f #define CT_ROLL_RELATIVE_CONTROL 0x10 #define CT_PRIVACY_CONTROL 0x11 /* Processing Unit controls */ #define PU_CONTROL_UNDEFINED 0x00 #define PU_BACKLIGHT_COMPENSATION_CONTROL 0x01 #define PU_BRIGHTNESS_CONTROL 0x02 #define PU_CONTRAST_CONTROL 0x03 #define PU_GAIN_CONTROL 0x04 #define PU_POWER_LINE_FREQUENCY_CONTROL 0x05 #define PU_HUE_CONTROL 0x06 #define PU_SATURATION_CONTROL 0x07 #define PU_SHARPNESS_CONTROL 0x08 #define PU_GAMMA_CONTROL 0x09 #define PU_WHITE_BALANCE_TEMPERATURE_CONTROL 0x0a #define PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL 0x0b #define PU_WHITE_BALANCE_COMPONENT_CONTROL 0x0c #define PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL 0x0d #define PU_DIGITAL_MULTIPLIER_CONTROL 0x0e #define PU_DIGITAL_MULTIPLIER_LIMIT_CONTROL 0x0f #define PU_HUE_AUTO_CONTROL 0x10 #define PU_ANALOG_VIDEO_STANDARD_CONTROL 0x11 #define PU_ANALOG_LOCK_STATUS_CONTROL 0x12 #define LXU_MOTOR_PANTILT_RELATIVE_CONTROL 0x01 #define LXU_MOTOR_PANTILT_RESET_CONTROL 0x02 #define LXU_MOTOR_FOCUS_MOTOR_CONTROL 0x03 /* VideoStreaming interface controls */ #define VS_CONTROL_UNDEFINED 0x00 #define VS_PROBE_CONTROL 0x01 #define VS_COMMIT_CONTROL 0x02 #define VS_STILL_PROBE_CONTROL 0x03 #define VS_STILL_COMMIT_CONTROL 0x04 #define VS_STILL_IMAGE_TRIGGER_CONTROL 0x05 #define VS_STREAM_ERROR_CODE_CONTROL 0x06 #define VS_GENERATE_KEY_FRAME_CONTROL 0x07 #define VS_UPDATE_FRAME_SEGMENT_CONTROL 0x08 #define VS_SYNC_DELAY_CONTROL 0x09 #define TT_VENDOR_SPECIFIC 0x0100 #define TT_STREAMING 0x0101 /* Input Terminal types */ #define ITT_VENDOR_SPECIFIC 0x0200 #define ITT_CAMERA 0x0201 #define ITT_MEDIA_TRANSPORT_INPUT 0x0202 /* Output Terminal types */ #define OTT_VENDOR_SPECIFIC 0x0300 #define OTT_DISPLAY 0x0301 #define OTT_MEDIA_TRANSPORT_OUTPUT 0x0302 /* External Terminal types */ #define EXTERNAL_VENDOR_SPECIFIC 0x0400 #define COMPOSITE_CONNECTOR 0x0401 #define SVIDEO_CONNECTOR 0x0402 #define COMPONENT_CONNECTOR 0x0403 #define UVC_TERM_INPUT 0x0000 #define UVC_TERM_OUTPUT 0x8000 #define UVC_ENTITY_TYPE(entity) ((entity)->type & 0x7fff) #define UVC_ENTITY_IS_UNIT(entity) (((entity)->type & 0xff00) == 0) #define UVC_ENTITY_IS_TERM(entity) (((entity)->type & 0xff00) != 0) #define UVC_ENTITY_IS_ITERM(entity) \ (((entity)->type & 0x8000) == UVC_TERM_INPUT) #define UVC_ENTITY_IS_OTERM(entity) \ (((entity)->type & 0x8000) == UVC_TERM_OUTPUT) #define UVC_STATUS_TYPE_CONTROL 1 #define UVC_STATUS_TYPE_STREAMING 2 /* ------------------------------------------------------------------------ * GUIDs */ #define UVC_GUID_UVC_CAMERA \ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01} #define UVC_GUID_UVC_OUTPUT \ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02} #define UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT \ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03} #define UVC_GUID_UVC_PROCESSING \ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01} #define UVC_GUID_UVC_SELECTOR \ {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02} #define UVC_GUID_LOGITECH_DEV_INFO \ {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \ 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1e} #define UVC_GUID_LOGITECH_USER_HW \ {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \ 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1f} #define UVC_GUID_LOGITECH_VIDEO \ {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \ 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x50} #define UVC_GUID_LOGITECH_MOTOR \ {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \ 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x56} #define UVC_GUID_FORMAT_MJPEG \ { 'M', 'J', 'P', 'G', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_YUY2 \ { 'Y', 'U', 'Y', '2', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_NV12 \ { 'N', 'V', '1', '2', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_YV12 \ { 'Y', 'V', '1', '2', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_I420 \ { 'I', '4', '2', '0', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_UYVY \ { 'U', 'Y', 'V', 'Y', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_Y800 \ { 'Y', '8', '0', '0', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} #define UVC_GUID_FORMAT_BY8 \ { 'B', 'Y', '8', ' ', 0x00, 0x00, 0x10, 0x00, \ 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71} /* ------------------------------------------------------------------------ * Driver specific constants. */ #define DRIVER_VERSION_NUMBER KERNEL_VERSION(0, 1, 0) /* Number of isochronous URBs. */ #define UVC_URBS 5 /* Maximum number of packets per URB. */ #define UVC_MAX_PACKETS 32 /* Maximum number of video buffers. */ #define UVC_MAX_VIDEO_BUFFERS 32 /* Maximum status buffer size in bytes of interrupt URB. */ #define UVC_MAX_STATUS_SIZE 16 #define UVC_CTRL_CONTROL_TIMEOUT 300 #define UVC_CTRL_STREAMING_TIMEOUT 3000 /* Devices quirks */ #define UVC_QUIRK_STATUS_INTERVAL 0x00000001 #define UVC_QUIRK_PROBE_MINMAX 0x00000002 #define UVC_QUIRK_PROBE_EXTRAFIELDS 0x00000004 #define UVC_QUIRK_BUILTIN_ISIGHT 0x00000008 #define UVC_QUIRK_STREAM_NO_FID 0x00000010 #define UVC_QUIRK_IGNORE_SELECTOR_UNIT 0x00000020 #define UVC_QUIRK_FIX_BANDWIDTH 0x00000080 /* Format flags */ #define UVC_FMT_FLAG_COMPRESSED 0x00000001 #define UVC_FMT_FLAG_STREAM 0x00000002 /* ------------------------------------------------------------------------ * Structures. */ struct uvc_device; /* TODO: Put the most frequently accessed fields at the beginning of * structures to maximize cache efficiency. */ struct uvc_streaming_control { __u16 bmHint; __u8 bFormatIndex; __u8 bFrameIndex; __u32 dwFrameInterval; __u16 wKeyFrameRate; __u16 wPFrameRate; __u16 wCompQuality; __u16 wCompWindowSize; __u16 wDelay; __u32 dwMaxVideoFrameSize; __u32 dwMaxPayloadTransferSize; __u32 dwClockFrequency; __u8 bmFramingInfo; __u8 bPreferedVersion; __u8 bMinVersion; __u8 bMaxVersion; }; struct uvc_menu_info { __u32 value; __u8 name[32]; }; struct uvc_control_info { struct list_head list; struct list_head mappings; __u8 entity[16]; __u8 index; __u8 selector; __u16 size; __u32 flags; }; struct uvc_control_mapping { struct list_head list; struct uvc_control_info *ctrl; __u32 id; __u8 name[32]; __u8 entity[16]; __u8 selector; __u8 size; __u8 offset; enum v4l2_ctrl_type v4l2_type; __u32 data_type; struct uvc_menu_info *menu_info; __u32 menu_count; __s32 (*get) (struct uvc_control_mapping *mapping, __u8 query, const __u8 *data); void (*set) (struct uvc_control_mapping *mapping, __s32 value, __u8 *data); }; struct uvc_control { struct uvc_entity *entity; struct uvc_control_info *info; __u8 index; /* Used to match the uvc_control entry with a uvc_control_info. */ __u8 dirty : 1, loaded : 1, modified : 1; __u8 *data; }; struct uvc_format_desc { char *name; __u8 guid[16]; __u32 fcc; }; /* The term 'entity' refers to both UVC units and UVC terminals. * * The type field is either the terminal type (wTerminalType in the terminal * descriptor), or the unit type (bDescriptorSubtype in the unit descriptor). * As the bDescriptorSubtype field is one byte long, the type value will * always have a null MSB for units. All terminal types defined by the UVC * specification have a non-null MSB, so it is safe to use the MSB to * differentiate between units and terminals as long as the descriptor parsing * code makes sure terminal types have a non-null MSB. * * For terminals, the type's most significant bit stores the terminal * direction (either UVC_TERM_INPUT or UVC_TERM_OUTPUT). The type field should * always be accessed with the UVC_ENTITY_* macros and never directly. */ struct uvc_entity { struct list_head list; /* Entity as part of a UVC device. */ struct list_head chain; /* Entity as part of a video device * chain. */ __u8 id; __u16 type; char name[64]; union { struct { __u16 wObjectiveFocalLengthMin; __u16 wObjectiveFocalLengthMax; __u16 wOcularFocalLength; __u8 bControlSize; __u8 *bmControls; } camera; struct { __u8 bControlSize; __u8 *bmControls; __u8 bTransportModeSize; __u8 *bmTransportModes; } media; struct { __u8 bSourceID; } output; struct { __u8 bSourceID; __u16 wMaxMultiplier; __u8 bControlSize; __u8 *bmControls; __u8 bmVideoStandards; } processing; struct { __u8 bNrInPins; __u8 *baSourceID; } selector; struct { __u8 guidExtensionCode[16]; __u8 bNumControls; __u8 bNrInPins; __u8 *baSourceID; __u8 bControlSize; __u8 *bmControls; __u8 *bmControlsType; } extension; }; unsigned int ncontrols; struct uvc_control *controls; }; struct uvc_frame { __u8 bFrameIndex; __u8 bmCapabilities; __u16 wWidth; __u16 wHeight; __u32 dwMinBitRate; __u32 dwMaxBitRate; __u32 dwMaxVideoFrameBufferSize; __u8 bFrameIntervalType; __u32 dwDefaultFrameInterval; __u32 *dwFrameInterval; }; struct uvc_format { __u8 type; __u8 index; __u8 bpp; __u8 colorspace; __u32 fcc; __u32 flags; char name[32]; unsigned int nframes; struct uvc_frame *frame; }; struct uvc_streaming_header { __u8 bNumFormats; __u8 bEndpointAddress; __u8 bTerminalLink; __u8 bControlSize; __u8 *bmaControls; /* The following fields are used by input headers only. */ __u8 bmInfo; __u8 bStillCaptureMethod; __u8 bTriggerSupport; __u8 bTriggerUsage; }; struct uvc_streaming { struct list_head list; struct usb_interface *intf; int intfnum; __u16 maxpsize; struct uvc_streaming_header header; enum v4l2_buf_type type; unsigned int nformats; struct uvc_format *format; struct uvc_streaming_control ctrl; struct uvc_format *cur_format; struct uvc_frame *cur_frame; struct mutex mutex; }; enum uvc_buffer_state { UVC_BUF_STATE_IDLE = 0, UVC_BUF_STATE_QUEUED = 1, UVC_BUF_STATE_ACTIVE = 2, UVC_BUF_STATE_DONE = 3, UVC_BUF_STATE_ERROR = 4, }; struct uvc_buffer { unsigned long vma_use_count; struct list_head stream; /* Touched by interrupt handler. */ struct v4l2_buffer buf; struct list_head queue; wait_queue_head_t wait; enum uvc_buffer_state state; }; #define UVC_QUEUE_STREAMING (1 << 0) #define UVC_QUEUE_DISCONNECTED (1 << 1) #define UVC_QUEUE_DROP_INCOMPLETE (1 << 2) struct uvc_video_queue { enum v4l2_buf_type type; void *mem; unsigned int flags; __u32 sequence; unsigned int count; unsigned int buf_size; unsigned int buf_used; struct uvc_buffer buffer[UVC_MAX_VIDEO_BUFFERS]; struct mutex mutex; /* protects buffers and mainqueue */ spinlock_t irqlock; /* protects irqqueue */ struct list_head mainqueue; struct list_head irqqueue; }; struct uvc_video_device { struct uvc_device *dev; struct video_device *vdev; atomic_t active; unsigned int frozen : 1; struct list_head iterms; /* Input terminals */ struct uvc_entity *oterm; /* Output terminal */ struct uvc_entity *sterm; /* USB streaming terminal */ struct uvc_entity *processing; struct uvc_entity *selector; struct list_head extensions; struct mutex ctrl_mutex; struct uvc_video_queue queue; /* Video streaming object, must always be non-NULL. */ struct uvc_streaming *streaming; void (*decode) (struct urb *urb, struct uvc_video_device *video, struct uvc_buffer *buf); /* Context data used by the bulk completion handler. */ struct { __u8 header[256]; unsigned int header_size; int skip_payload; __u32 payload_size; __u32 max_payload_size; } bulk; struct urb *urb[UVC_URBS]; char *urb_buffer[UVC_URBS]; dma_addr_t urb_dma[UVC_URBS]; unsigned int urb_size; __u8 last_fid; }; enum uvc_device_state { UVC_DEV_DISCONNECTED = 1, }; struct uvc_device { struct usb_device *udev; struct usb_interface *intf; unsigned long warnings; __u32 quirks; int intfnum; char name[32]; enum uvc_device_state state; struct kref kref; struct list_head list; atomic_t users; /* Video control interface */ __u16 uvc_version; __u32 clock_frequency; struct list_head entities; struct uvc_video_device video; /* Status Interrupt Endpoint */ struct usb_host_endpoint *int_ep; struct urb *int_urb; __u8 *status; struct input_dev *input; char input_phys[64]; /* Video Streaming interfaces */ struct list_head streaming; }; enum uvc_handle_state { UVC_HANDLE_PASSIVE = 0, UVC_HANDLE_ACTIVE = 1, }; struct uvc_fh { struct uvc_video_device *device; enum uvc_handle_state state; }; struct uvc_driver { struct usb_driver driver; struct mutex open_mutex; /* protects from open/disconnect race */ struct list_head devices; /* struct uvc_device list */ struct list_head controls; /* struct uvc_control_info list */ struct mutex ctrl_mutex; /* protects controls and devices lists */ }; /* ------------------------------------------------------------------------ * Debugging, printing and logging */ #define UVC_TRACE_PROBE (1 << 0) #define UVC_TRACE_DESCR (1 << 1) #define UVC_TRACE_CONTROL (1 << 2) #define UVC_TRACE_FORMAT (1 << 3) #define UVC_TRACE_CAPTURE (1 << 4) #define UVC_TRACE_CALLS (1 << 5) #define UVC_TRACE_IOCTL (1 << 6) #define UVC_TRACE_FRAME (1 << 7) #define UVC_TRACE_SUSPEND (1 << 8) #define UVC_TRACE_STATUS (1 << 9) #define UVC_WARN_MINMAX 0 #define UVC_WARN_PROBE_DEF 1 extern unsigned int uvc_no_drop_param; extern unsigned int uvc_trace_param; extern unsigned int uvc_timeout_param; #define uvc_trace(flag, msg...) \ do { \ if (uvc_trace_param & flag) \ printk(KERN_DEBUG "uvcvideo: " msg); \ } while (0) #define uvc_warn_once(dev, warn, msg...) \ do { \ if (!test_and_set_bit(warn, &dev->warnings)) \ printk(KERN_INFO "uvcvideo: " msg); \ } while (0) #define uvc_printk(level, msg...) \ printk(level "uvcvideo: " msg) #define UVC_GUID_FORMAT "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-" \ "%02x%02x%02x%02x%02x%02x" #define UVC_GUID_ARGS(guid) \ (guid)[3], (guid)[2], (guid)[1], (guid)[0], \ (guid)[5], (guid)[4], \ (guid)[7], (guid)[6], \ (guid)[8], (guid)[9], \ (guid)[10], (guid)[11], (guid)[12], \ (guid)[13], (guid)[14], (guid)[15] /* -------------------------------------------------------------------------- * Internal functions. */ /* Core driver */ extern struct uvc_driver uvc_driver; extern void uvc_delete(struct kref *kref); /* Video buffers queue management. */ extern void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type); extern int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers, unsigned int buflength); extern int uvc_free_buffers(struct uvc_video_queue *queue); extern int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf); extern int uvc_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf); extern int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf, int nonblocking); extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable); extern void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect); extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf); extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file, poll_table *wait); extern int uvc_queue_allocated(struct uvc_video_queue *queue); static inline int uvc_queue_streaming(struct uvc_video_queue *queue) { return queue->flags & UVC_QUEUE_STREAMING; } /* V4L2 interface */ extern const struct v4l2_file_operations uvc_fops; /* Video */ extern int uvc_video_init(struct uvc_video_device *video); extern int uvc_video_suspend(struct uvc_video_device *video); extern int uvc_video_resume(struct uvc_video_device *video); extern int uvc_video_enable(struct uvc_video_device *video, int enable); extern int uvc_probe_video(struct uvc_video_device *video, struct uvc_streaming_control *probe); extern int uvc_commit_video(struct uvc_video_device *video, struct uvc_streaming_control *ctrl); extern int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit, __u8 intfnum, __u8 cs, void *data, __u16 size); /* Status */ extern int uvc_status_init(struct uvc_device *dev); extern void uvc_status_cleanup(struct uvc_device *dev); extern int uvc_status_start(struct uvc_device *dev); extern void uvc_status_stop(struct uvc_device *dev); extern int uvc_status_suspend(struct uvc_device *dev); extern int uvc_status_resume(struct uvc_device *dev); /* Controls */ extern struct uvc_control *uvc_find_control(struct uvc_video_device *video, __u32 v4l2_id, struct uvc_control_mapping **mapping); extern int uvc_query_v4l2_ctrl(struct uvc_video_device *video, struct v4l2_queryctrl *v4l2_ctrl); extern int uvc_ctrl_add_info(struct uvc_control_info *info); extern int uvc_ctrl_add_mapping(struct uvc_control_mapping *mapping); extern int uvc_ctrl_init_device(struct uvc_device *dev); extern void uvc_ctrl_cleanup_device(struct uvc_device *dev); extern int uvc_ctrl_resume_device(struct uvc_device *dev); extern void uvc_ctrl_init(void); extern int uvc_ctrl_begin(struct uvc_video_device *video); extern int __uvc_ctrl_commit(struct uvc_video_device *video, int rollback); static inline int uvc_ctrl_commit(struct uvc_video_device *video) { return __uvc_ctrl_commit(video, 0); } static inline int uvc_ctrl_rollback(struct uvc_video_device *video) { return __uvc_ctrl_commit(video, 1); } extern int uvc_ctrl_get(struct uvc_video_device *video, struct v4l2_ext_control *xctrl); extern int uvc_ctrl_set(struct uvc_video_device *video, struct v4l2_ext_control *xctrl); extern int uvc_xu_ctrl_query(struct uvc_video_device *video, struct uvc_xu_control *ctrl, int set); /* Utility functions */ extern void uvc_simplify_fraction(uint32_t *numerator, uint32_t *denominator, unsigned int n_terms, unsigned int threshold); extern uint32_t uvc_fraction_to_interval(uint32_t numerator, uint32_t denominator); extern struct usb_host_endpoint *uvc_find_endpoint( struct usb_host_interface *alts, __u8 epaddr); /* Quirks support */ void uvc_video_decode_isight(struct urb *urb, struct uvc_video_device *video, struct uvc_buffer *buf); #endif /* __KERNEL__ */ #endif
Makefile:
KERN_DIR = /usr/src/linux-headers-2.6.31-14-generic
all:
make -C $(KERN_DIR) M=`pwd` modules
clean:
make -C $(KERN_DIR) M=`pwd` modules clean
rm -rf modules.order
obj-m += myuvc.o
驅動移植好了,插上攝像頭,執行lsusb就可以看到攝像頭資料,或者在 ls /dev/video0 就是攝像頭驅動的裝置節點,下面我講解開發過程可以選擇的應用程式。
Servfox,Spcaview和luvcview。這三個都可以實現的,我也寫了一個應用程式來測試攝像頭資料,是在LCD上顯示攝像頭資料,首先需要移植好LCD驅動程式。
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