自己写的uvc驱动支持IP2977/ip2970

/* 作者: [e-mail] * 此驱动程序是基于linux2.6.31.14内核 * 上一篇自己写的uvc驱动程序是针对环宇飞扬6190来写的，有一些缺点，这些缺点在本次的驱动 * 中进行了修改此uvc驱动是针对IP2977进行了支持，根据IP2977芯片厂商提供的修改手册进行了修改。 * 此驱动程序虽然支持IP2977摄像头，但是显示效果不太好，此驱动只是针对学习使用。 */#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 #include #include <media v4l2-common="" h="">#include <media v4l2-ioctl="" h="">#include <media videobuf-core="" h="">#include "uvcvideo.h"/* 参考 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;};/* 参考uvc_video_queue定义一些结构体 */struct myuvc_buffer { struct v4l2_buffer buf; int state; int vma_use_count; /* 表示是否已经被mmap */ wait_queue_head_t wait; /* APP要读某个缓冲区,如果无数据,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消费用 */struct list_head irqqueue; /* 供底层驱动生产用 */};static struct myuvc_queue myuvc_queue;static struct video_device *myuvc_vdev;static struct usb_device *myuvc_udev;static int myuvc_bEndpointAddress = 0x82;static int myuvc_streaming_intf;static int myuvc_control_intf;static struct v4l2_format myuvc_format;static struct frame_desc frames[] = {{640, 480}, {320, 240}, {160, 120}};static int frame_idx = 1;static int bBitsPerPixel = 0; /* lsusb -v -d 0x1e4e: "bBitsPerPixel" */static int uvc_version = 0x0100; /* lsusb -v -d 0x1b3b: bcdUVC */static int ProcessingUnitID = 3; /* lsusb -v -d 0x1b3b: PROCESSING_UNIT *//* 以后再设置 */static int wMaxPacketSize = 800;static int myuvc_streaming_bAlternateSetting = 5;static int dwMaxVideoFrameSize = 77312;static struct myuvc_streaming_control myuvc_params;static int last_fid = -1;/* A2 参考 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 列举支持哪种格式 * 参考: uvc_fmts 数组 */static int myuvc_vidioc_enum_fmt_vid_cap(struct file *file, void *priv,struct v4l2_fmtdesc *f){ /* 人工查看描述符可知我们用的摄像头只支持1种格式 */if (f->index >= 1)return -EINVAL;strcpy(f->description, "MJPEG");f->pixelformat = V4L2_PIX_FMT_MJPEG; //f->flags = ;f->type = V4L2_BUF_TYPE_VIDEO_CAPTURE; return 0;}/* A4 返回当前所使用的格式 */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 测试驱动程序是否支持某种格式, 强制设置该格式 * 参考: 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_MJPEG) return -EINVAL; /* 调整format的width, height, * 计算bytesperline, sizeimage */ /* 人工查看描述符, 确定支持哪几种分辨率 */ f->fmt.pix.width = frames[frame_idx].width; f->fmt.pix.height = frames[frame_idx].height;/* 对于MJPEG数据类型来说，bBitsPerPixel是无法知道的。因此我们设为0 */f->fmt.pix.bytesperline =(f->fmt.pix.width * bBitsPerPixel) >> 3;/* 一帧数据最大为dwMaxVideoFrameSize=77312,是由确定带宽时确定出来的。 */f->fmt.pix.sizeimage = dwMaxVideoFrameSize;f->fmt.pix.field = V4L2_FIELD_NONE;/* 由描述符bColorPrimaries 1 (BT.709,sRGB)可知 */f->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;f->fmt.pix.priv = 0;/* private data, depends on pixelformat */ return 0;}/* A6 参考 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调用该ioctl让驱动程序分配若干个缓存, APP将从这些缓存中读到视频数据 * 参考: 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; } /* 这些缓存是一次性作为一个整体来分配的 */ 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 查询缓存状态, 比如地址信息(APP可以用mmap进行映射) * 参考 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 把缓冲区放入队列, 底层的硬件操作函数将会把数据放入这个队列的缓存 * 参考: uvc_queue_buffer */static int myuvc_vidioc_qbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf){ struct myuvc_buffer *buf; /* 0. APP传入的v4l2_buf可能有问题, 要做判断 */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. 修改状态 */buf->state = VIDEOBUF_QUEUED;buf->buf.bytesused = 0; /* 2. 放入2个队列 */ /* 队列1: 供APP使用 * 当缓冲区没有数据时,放入mainqueue队列 * 当缓冲区有数据时, APP从mainqueue队列中取出 */list_add_tail(&buf->stream, &myuvc_queue.mainqueue); /* 队列2: 供产生数据的函数使用 * 当采集到数据时,从irqqueue队列中取出第1个缓冲区,存入数据 */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);}/* 参考: 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;}/* 参考: 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; }/* 参考: 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; } }}/* 参考: 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;static int fid;static int wake_cnt = 0; // 要修改影像資料，必須先宣告一個特別型態的指標變數，才能正確存取記憶體中的資料 unsigned char *point_mem; static unsigned char *mem_temp = NULL; // 初始化暫存用的記憶體位置 static unsigned int nArrayTemp_Size = 1000;u8* mem;int data_len; switch (urb->status) {case 0:break;default:printk("Non-zero status (%d) in video ""completion handler.\n", urb->status);return;} /* 如果irqqueue队列不空的话，从irqqueue队列中取出第1个缓冲区，用于存放urb的数据 */if (!list_empty(&myuvc_queue.irqqueue)){buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);}else{/* 什么情况下会导致irqqueue队列为空呢? * usb设备填充数据太快，但是应用程序没能及时处理 */buf = NULL;} /* 开始处理urb中的每一个小包 */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; len = urb->iso_frame_desc[i].actual_length; /* 判断数据是否有效 */ /* URB数据含义: * data[0] : 头部长度 * data[1] : 错误状态 */ 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; } /* 根据ip2970/ip2977厂家提供的修改手册，如果想要支持ip2970/ip2977就必须 * 添加如下代码 */ if (myuvc_udev->descriptor.idVendor == 0x1B3B) { if ( len >= 16 ) // have data in buffer { // 資料必須從data[12]開始判斷，是因為前面的資料是封包專用 if ( (src[12]==0xFF && src[13]==0xD8 && src[14]==0xFF) || (src[12]==0xD8 && src[13]==0xFF && src[14]==0xC4)) { if(last_fid) fid &= ~UVC_STREAM_FID; else fid |= UVC_STREAM_FID; } } } else { fid = src[1] & UVC_STREAM_FID; }/* Store the payload FID bit and return immediately when the buffer is * NULL. */if (buf == NULL) {last_fid = fid;continue;}/* 根据FID判断当前帧的数据是否结束 *//* VIDEOBUF_ACTIVE表示正在接收数据，buf->state!= VIDEOBUF_ACTIVE, 表示"之前还未接收数据"， * 因此就是说即将接收数据*/if (buf->state != VIDEOBUF_ACTIVE) { if (fid == last_fid) {/* 既然你刚开始接收数据, 那么FID应该是一个新的值,不应该等于原来的last_fid */continue;}/* 表示开始接收第1个数据 */buf->state = VIDEOBUF_ACTIVE;}/* fid表示当前的fid。 * fid != last_fid 表示开始新一帧了，当前的buffer已经被填充完了。 * 这个地方是从fid来判断是否一帧数据已经结束，下面还有从数据是否填充不下了来 * 强制认为一帧数据已经结束 */if (fid != last_fid && buf->buf.bytesused != 0) {buf->state = VIDEOBUF_DONE;/* 从队列中删除, 唤醒进程 */ list_del(&buf->irq); wake_up(&buf->wait);mem = myuvc_queue.mem + buf->buf.m.offset;data_len = buf->buf.bytesused;//printk("wake_up %d : %s %d, start data: %02x %02x, end data: %02x %02x", wake_cnt++, __FUNCTION__, __LINE__, mem[0], mem[1], mem[data_len - 2], mem[data_len - 1]);/* 取出下一个buf */if (!list_empty(&myuvc_queue.irqqueue)){buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);}else{buf = NULL;}continue;}last_fid = fid; dest = myuvc_queue.mem + buf->buf.m.offset + buf->buf.bytesused; /* 除去头部后的数据长度 */ len -= src[0]; /* 缓冲区最多还能存多少数据 */ maxlen = buf->buf.length - buf->buf.bytesused; nbytes = min(len, maxlen); /* 复制数据 */ memcpy(dest, src + src[0], nbytes); buf->buf.bytesused += nbytes; /* ip2970/ip2977 */ if (myuvc_udev->descriptor.idVendor == 0x1B3B) { if(mem_temp == NULL) { mem_temp = kmalloc(nArrayTemp_Size, GFP_KERNEL); } else if(nArrayTemp_Size <= nbytes){ // 當收到的資料長度大於上一次的資料長度，則重新分配所需的空間+ kfree(mem_temp); nArrayTemp_Size += 500; mem_temp = kmalloc(nArrayTemp_Size, GFP_KERNEL); } memset(mem_temp, 0x00, nArrayTemp_Size); // 指向資料儲存的記憶體位置 point_mem = (unsigned char *)dest; if( *(point_mem) == 0xD8 && *(point_mem + 1) == 0xFF && *(point_mem + 2) == 0xC4){ memcpy( mem_temp + 1, point_mem, nbytes); mem_temp[0] = 0xFF; memcpy(point_mem, mem_temp, nbytes + 1); } } /* 判断一帧数据是否已经全部接收到 * 如果数据已经满了，就强制认为已经结束了 */ 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; } /* 当接收完一帧数据, * 从irqqueue中删除这个缓冲区 * 唤醒等待数据的进程 */ if (buf->state == VIDEOBUF_DONE || buf->state == VIDEOBUF_ERROR) { list_del(&buf->irq); wake_up(&buf->wait);mem = myuvc_queue.mem + buf->buf.m.offset;data_len = buf->buf.bytesused;//printk("wake_up %d : %s %d, start data: %02x %02x, end data: %02x %02x", wake_cnt++, __FUNCTION__, __LINE__, mem[0], mem[1], mem[data_len - 2], mem[data_len - 1]);/* 取出下一个buf */if (!list_empty(&myuvc_queue.irqqueue)){buf = list_first_entry(&myuvc_queue.irqqueue, struct myuvc_buffer, irq);}else{buf = NULL;} }} /* 再次提交URB */if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {printk("Failed to resubmit video URB (%d).\n", ret);}}/* 参考: 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; /* 实时传输端点一次能传输的最大字节数 */size = myuvc_params.dwMaxVideoFrameSize; /* 一帧数据的最大长度 */ 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. 设置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 启动传输 * 参考: 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摄像头设置参数: 比如使用哪个format, 使用这个format下的哪个frame(分辨率) * 参考: uvc_set_video_ctrl / uvc_get_video_ctrl * 1.1 根据一个结构体uvc_streaming_control设置数据包: 可以手工设置,也可以读出后再修改 * 1.2 调用usb_control_msg发出数据包 */ /* a. 测试参数 */ ret = myuvc_try_streaming_params(&myuvc_params); printk("myuvc_try_streaming_params ret = %d\n", ret); /* b. 取出参数 */ ret = myuvc_get_streaming_params(&myuvc_params); printk("myuvc_get_streaming_params ret = %d\n", ret); /* c. 设置参数 */ ret = myuvc_set_streaming_params(&myuvc_params); printk("myuvc_set_streaming_params ret = %d\n", ret); myuvc_print_streaming_params(&myuvc_params); /* d. 设置VideoStreaming Interface所使用的setting * d.1 从myuvc_params确定带宽 * d.2 根据setting的endpoint能传输的wMaxPacketSize * 找到能满足该带宽的setting */ /* 手工确定: * bandwidth = myuvc_params.dwMaxPayloadTransferSize = 800 * 观察lsusb -v -d 0x1e4e:的结果: * wMaxPacketSize 0x0320 1x 800 bytes * bAlternateSetting 5 */ usb_set_interface(myuvc_udev, myuvc_streaming_intf, myuvc_streaming_bAlternateSetting); /* 2. 分配设置URB */ ret = myuvc_alloc_init_urbs(); if (ret) printk("myuvc_alloc_init_urbs err : ret = %d\n", ret); /* 3. 提交URB以接收数据 */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通过poll/select确定有数据后, 把缓存从队列中取出来 * 参考: uvc_dequeue_buffer */static int myuvc_vidioc_dqbuf(struct file *file, void *priv, struct v4l2_buffer *v4l2_buf){ /* APP发现数据就绪后, 从mainqueue里取出这个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);memcpy(v4l2_buf, &buf->buf, sizeof *v4l2_buf);done:return ret;}/* * A14 之前已经通过mmap映射了缓存, APP可以直接读数据 * A15 再次调用myuvc_vidioc_qbuf把缓存放入队列 * A16 poll... *//* A17 停止 * 参考 : 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. 设置VideoStreaming Interface为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;}} /* 参考: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; /* 发起USB传输确定这些值 */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;}/* 参考 : 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;}/* 参考: 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 = { // 表示它是一个摄像头设备 .vidioc_querycap = myuvc_vidioc_querycap, /* 用于列举、获得、测试、设置摄像头的数据的格式 */ .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, /* 缓冲区操作: 申请/查询/放入队列/取出队列 */ .vidioc_reqbufs = myuvc_vidioc_reqbufs, .vidioc_querybuf = myuvc_vidioc_querybuf, .vidioc_qbuf = myuvc_vidioc_qbuf, .vidioc_dqbuf = myuvc_vidioc_dqbuf, /* 查询/获得/设置属性 */ .vidioc_queryctrl = myuvc_vidioc_queryctrl, .vidioc_g_ctrl = myuvc_vidioc_g_ctrl, .vidioc_s_ctrl = myuvc_vidioc_s_ctrl, // 启动/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 把缓存映射到APP的空间,以后APP就可以直接操作这块缓存 * 参考: 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; /* 应用程序调用mmap函数时, 会传入offset参数 * 根据这个offset找出指定的缓冲区 */ 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; /* 根据虚拟地址找到缓冲区对应的page构体 */ addr = (unsigned long)myuvc_queue.mem + buffer->buf.m.offset; while (size > 0) { page = vmalloc_to_page((void *)addr); /* 把page和APP传入的虚拟地址挂构 */ 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调用POLL/select来确定缓存是否就绪(有数据) * 参考 : uvc_v4l2_poll */static unsigned int myuvc_poll(struct file *file, struct poll_table_struct *wait){struct myuvc_buffer *buf;unsigned int mask = 0; /* 从mainqueuq中取出第1个缓冲区 */ /*判断它的状态, 如果未就绪, 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 关闭 */static int myuvc_vidioc_streamoff(struct file *file, void *priv, enum v4l2_buf_type t);static int myuvc_close(struct file *file){ myuvc_vidioc_streamoff(NULL, NULL, 0);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);int ret; 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. 分配一个video_device结构体 */ myuvc_vdev = video_device_alloc(); /* 2. 设置 */ /* 2.1 */ myuvc_vdev->release = myuvc_release; /* 2.2 */ myuvc_vdev->fops = &myuvc_fops; /* 2.3 */ myuvc_vdev->ioctl_ops = &myuvc_ioctl_ops; /* 3. 注册 */ video_register_device(myuvc_vdev, VFL_TYPE_GRABBER, -1);/* 为了确定带宽,使用哪一个setting */ /* a. 测试参数 */ ret = myuvc_try_streaming_params(&myuvc_params); printk("myuvc_try_streaming_params ret = %d\n", ret); /* b. 取出参数 */ ret = myuvc_get_streaming_params(&myuvc_params); printk("myuvc_get_streaming_params ret = %d\n", ret); /* c. 设置参数 */ ret = myuvc_set_streaming_params(&myuvc_params); printk("myuvc_set_streaming_params ret = %d\n", ret); myuvc_print_streaming_params(&myuvc_params); } 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. 设置 */static struct usb_driver myuvc_driver = { .name = "myuvc", .probe = myuvc_probe, .disconnect = myuvc_disconnect, .id_table = myuvc_ids,};static int myuvc_init(void){ /* 3. 注册 */ 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");</media></media></media></asm></asm></linux></linux></linux></linux></linux></linux></linux></linux>