vivi.c

来自「linux 内核源代码」· C语言 代码 · 共 1,211 行 · 第 1/2 页

/*
 * Virtual Video driver - This code emulates a real video device with v4l2 api
 *
 * Copyright (c) 2006 by:
 *      Mauro Carvalho Chehab <mchehab--a.t--infradead.org>
 *      Ted Walther <ted--a.t--enumera.com>
 *      John Sokol <sokol--a.t--videotechnology.com>
 *      http://v4l.videotechnology.com/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the BSD Licence, GNU General Public License
 * as published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version
 */
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/random.h>
#include <linux/version.h>
#include <linux/mutex.h>
#include <linux/videodev2.h>
#include <linux/dma-mapping.h>
#ifdef CONFIG_VIDEO_V4L1_COMPAT
/* Include V4L1 specific functions. Should be removed soon */
#include <linux/videodev.h>
#endif
#include <linux/interrupt.h>
#include <media/videobuf-vmalloc.h>
#include <media/v4l2-common.h>
#include <linux/kthread.h>
#include <linux/highmem.h>
#include <linux/freezer.h>

/* Wake up at about 30 fps */
#define WAKE_NUMERATOR 30
#define WAKE_DENOMINATOR 1001
#define BUFFER_TIMEOUT     msecs_to_jiffies(500)  /* 0.5 seconds */

/* These timers are for 1 fps - used only for testing */
//#define WAKE_DENOMINATOR 30 /* hack for testing purposes */
//#define BUFFER_TIMEOUT     msecs_to_jiffies(5000)  /* 5 seconds */

#include "font.h"

#define VIVI_MAJOR_VERSION 0
#define VIVI_MINOR_VERSION 4
#define VIVI_RELEASE 0
#define VIVI_VERSION KERNEL_VERSION(VIVI_MAJOR_VERSION, VIVI_MINOR_VERSION, VIVI_RELEASE)

/* Declare static vars that will be used as parameters */
static unsigned int vid_limit = 16;	/* Video memory limit, in Mb */
static struct video_device vivi;	/* Video device */
static int video_nr = -1;		/* /dev/videoN, -1 for autodetect */

/* supported controls */
static struct v4l2_queryctrl vivi_qctrl[] = {
	{
		.id            = V4L2_CID_AUDIO_VOLUME,
		.name          = "Volume",
		.minimum       = 0,
		.maximum       = 65535,
		.step          = 65535/100,
		.default_value = 65535,
		.flags         = 0,
		.type          = V4L2_CTRL_TYPE_INTEGER,
	},{
		.id            = V4L2_CID_BRIGHTNESS,
		.type          = V4L2_CTRL_TYPE_INTEGER,
		.name          = "Brightness",
		.minimum       = 0,
		.maximum       = 255,
		.step          = 1,
		.default_value = 127,
		.flags         = 0,
	}, {
		.id            = V4L2_CID_CONTRAST,
		.type          = V4L2_CTRL_TYPE_INTEGER,
		.name          = "Contrast",
		.minimum       = 0,
		.maximum       = 255,
		.step          = 0x1,
		.default_value = 0x10,
		.flags         = 0,
	}, {
		.id            = V4L2_CID_SATURATION,
		.type          = V4L2_CTRL_TYPE_INTEGER,
		.name          = "Saturation",
		.minimum       = 0,
		.maximum       = 255,
		.step          = 0x1,
		.default_value = 127,
		.flags         = 0,
	}, {
		.id            = V4L2_CID_HUE,
		.type          = V4L2_CTRL_TYPE_INTEGER,
		.name          = "Hue",
		.minimum       = -128,
		.maximum       = 127,
		.step          = 0x1,
		.default_value = 0,
		.flags         = 0,
	}
};

static int qctl_regs[ARRAY_SIZE(vivi_qctrl)];

#define dprintk(level,fmt, arg...)					\
	do {								\
		if (vivi.debug >= (level))				\
			printk(KERN_DEBUG "vivi: " fmt , ## arg);	\
	} while (0)

/* ------------------------------------------------------------------
	Basic structures
   ------------------------------------------------------------------*/

struct vivi_fmt {
	char  *name;
	u32   fourcc;          /* v4l2 format id */
	int   depth;
};

static struct vivi_fmt format = {
	.name     = "4:2:2, packed, YUYV",
	.fourcc   = V4L2_PIX_FMT_YUYV,
	.depth    = 16,
};

struct sg_to_addr {
	int pos;
	struct scatterlist *sg;
};

/* buffer for one video frame */
struct vivi_buffer {
	/* common v4l buffer stuff -- must be first */
	struct videobuf_buffer vb;

	struct vivi_fmt        *fmt;
};

struct vivi_dmaqueue {
	struct list_head       active;
	struct list_head       queued;
	struct timer_list      timeout;

	/* thread for generating video stream*/
	struct task_struct         *kthread;
	wait_queue_head_t          wq;
	/* Counters to control fps rate */
	int                        frame;
	int                        ini_jiffies;
};

static LIST_HEAD(vivi_devlist);

struct vivi_dev {
	struct list_head           vivi_devlist;

	struct mutex               lock;

	int                        users;

	/* various device info */
	struct video_device        vfd;

	struct vivi_dmaqueue       vidq;

	/* Several counters */
	int                        h,m,s,us,jiffies;
	char                       timestr[13];
};

struct vivi_fh {
	struct vivi_dev            *dev;

	/* video capture */
	struct vivi_fmt            *fmt;
	unsigned int               width,height;
	struct videobuf_queue      vb_vidq;

	enum v4l2_buf_type         type;
};

/* ------------------------------------------------------------------
	DMA and thread functions
   ------------------------------------------------------------------*/

/* Bars and Colors should match positions */

enum colors {
	WHITE,
	AMBAR,
	CYAN,
	GREEN,
	MAGENTA,
	RED,
	BLUE
};

static u8 bars[8][3] = {
	/* R   G   B */
	{204,204,204},	/* white */
	{208,208,  0},  /* ambar */
	{  0,206,206},  /* cyan */
	{  0,239,  0},  /* green */
	{239,  0,239},  /* magenta */
	{205,  0,  0},  /* red */
	{  0,  0,255},  /* blue */
	{  0,  0,  0}
};

#define TO_Y(r,g,b) (((16829*r +33039*g +6416*b  + 32768)>>16)+16)
/* RGB to  V(Cr) Color transform */
#define TO_V(r,g,b) (((28784*r -24103*g -4681*b  + 32768)>>16)+128)
/* RGB to  U(Cb) Color transform */
#define TO_U(r,g,b) (((-9714*r -19070*g +28784*b + 32768)>>16)+128)

#define TSTAMP_MIN_Y 24
#define TSTAMP_MAX_Y TSTAMP_MIN_Y+15
#define TSTAMP_MIN_X 64

static void gen_line(char *basep,int inipos,int wmax,
		     int hmax, int line, int count, char *timestr)
{
	int  w,i,j,pos=inipos,y;
	char *p,*s;
	u8   chr,r,g,b,color;

	/* We will just duplicate the second pixel at the packet */
	wmax/=2;

	/* Generate a standard color bar pattern */
	for (w=0;w<wmax;w++) {
		int colorpos=((w+count)*8/(wmax+1)) % 8;
		r=bars[colorpos][0];
		g=bars[colorpos][1];
		b=bars[colorpos][2];

		for (color=0;color<4;color++) {
			p=basep+pos;

			switch (color) {
				case 0:
				case 2:
					*p=TO_Y(r,g,b);		/* Luminance */
					break;
				case 1:
					*p=TO_U(r,g,b);		/* Cb */
					break;
				case 3:
					*p=TO_V(r,g,b);		/* Cr */
					break;
			}
			pos++;
		}
	}

	/* Checks if it is possible to show timestamp */
	if (TSTAMP_MAX_Y>=hmax)
		goto end;
	if (TSTAMP_MIN_X+strlen(timestr)>=wmax)
		goto end;

	/* Print stream time */
	if (line>=TSTAMP_MIN_Y && line<=TSTAMP_MAX_Y) {
		j=TSTAMP_MIN_X;
		for (s=timestr;*s;s++) {
			chr=rom8x16_bits[(*s-0x30)*16+line-TSTAMP_MIN_Y];
			for (i=0;i<7;i++) {
				if (chr&1<<(7-i)) { /* Font color*/
					r=bars[BLUE][0];
					g=bars[BLUE][1];
					b=bars[BLUE][2];
					r=g=b=0;
					g=198;
				} else { /* Background color */
					r=bars[WHITE][0];
					g=bars[WHITE][1];
					b=bars[WHITE][2];
					r=g=b=0;
				}

				pos=inipos+j*2;
				for (color=0;color<4;color++) {
					p=basep+pos;

					y=TO_Y(r,g,b);

					switch (color) {
						case 0:
						case 2:
							*p=TO_Y(r,g,b);		/* Luminance */
							break;
						case 1:
							*p=TO_U(r,g,b);		/* Cb */
							break;
						case 3:
							*p=TO_V(r,g,b);		/* Cr */
							break;
					}
					pos++;
				}
				j++;
			}
		}
	}


end:
	return;
}
static void vivi_fillbuff(struct vivi_dev *dev,struct vivi_buffer *buf)
{
	int h,pos=0;
	int hmax  = buf->vb.height;
	int wmax  = buf->vb.width;
	struct timeval ts;
	char *tmpbuf = kmalloc(wmax*2,GFP_KERNEL);
	void *vbuf=videobuf_to_vmalloc (&buf->vb);
	/* FIXME: move to dev struct */
	static int mv_count=0;

	if (!tmpbuf)
		return;

	for (h=0;h<hmax;h++) {
		gen_line(tmpbuf,0,wmax,hmax,h,mv_count,
			 dev->timestr);
		/* FIXME: replacing to __copy_to_user */
		if (copy_to_user(vbuf+pos,tmpbuf,wmax*2)!=0)
			dprintk(2,"vivifill copy_to_user failed.\n");
		pos += wmax*2;
	}

	mv_count++;

	kfree(tmpbuf);

	/* Updates stream time */

	dev->us+=jiffies_to_usecs(jiffies-dev->jiffies);
	dev->jiffies=jiffies;
	if (dev->us>=1000000) {
		dev->us-=1000000;
		dev->s++;
		if (dev->s>=60) {
			dev->s-=60;
			dev->m++;
			if (dev->m>60) {
				dev->m-=60;
				dev->h++;
				if (dev->h>24)
					dev->h-=24;
			}
		}
	}
	sprintf(dev->timestr,"%02d:%02d:%02d:%03d",
			dev->h,dev->m,dev->s,(dev->us+500)/1000);

	dprintk(2,"vivifill at %s: Buffer 0x%08lx size= %d\n",dev->timestr,
			(unsigned long)tmpbuf,pos);

	/* Advice that buffer was filled */
	buf->vb.state = STATE_DONE;
	buf->vb.field_count++;
	do_gettimeofday(&ts);
	buf->vb.ts = ts;

	list_del(&buf->vb.queue);
	wake_up(&buf->vb.done);
}

static int restart_video_queue(struct vivi_dmaqueue *dma_q);

static void vivi_thread_tick(struct vivi_dmaqueue  *dma_q)
{
	struct vivi_buffer    *buf;
	struct vivi_dev *dev= container_of(dma_q,struct vivi_dev,vidq);

	int bc;

	/* Announces videobuf that all went ok */
	for (bc = 0;; bc++) {
		if (list_empty(&dma_q->active)) {
			dprintk(1,"No active queue to serve\n");
			break;
		}

		buf = list_entry(dma_q->active.next,
				 struct vivi_buffer, vb.queue);

		/* Nobody is waiting something to be done, just return */
		if (!waitqueue_active(&buf->vb.done)) {
			mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
			return;
		}

		do_gettimeofday(&buf->vb.ts);
		dprintk(2,"[%p/%d] wakeup\n",buf,buf->vb.i);

		/* Fill buffer */
		vivi_fillbuff(dev,buf);

		if (list_empty(&dma_q->active)) {
			del_timer(&dma_q->timeout);
		} else {
			mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
		}
	}
	if (bc != 1)
		dprintk(1,"%s: %d buffers handled (should be 1)\n",__FUNCTION__,bc);
}

static void vivi_sleep(struct vivi_dmaqueue  *dma_q)
{
	int timeout;
	DECLARE_WAITQUEUE(wait, current);

	dprintk(1,"%s dma_q=0x%08lx\n",__FUNCTION__,(unsigned long)dma_q);

	add_wait_queue(&dma_q->wq, &wait);
	if (!kthread_should_stop()) {
		dma_q->frame++;

		/* Calculate time to wake up */
		timeout=dma_q->ini_jiffies+msecs_to_jiffies((dma_q->frame*WAKE_NUMERATOR*1000)/WAKE_DENOMINATOR)-jiffies;

		if (timeout <= 0) {
			int old=dma_q->frame;
			dma_q->frame=(jiffies_to_msecs(jiffies-dma_q->ini_jiffies)*WAKE_DENOMINATOR)/(WAKE_NUMERATOR*1000)+1;

			timeout=dma_q->ini_jiffies+msecs_to_jiffies((dma_q->frame*WAKE_NUMERATOR*1000)/WAKE_DENOMINATOR)-jiffies;

			dprintk(1,"underrun, losed %d frames. "
				  "Now, frame is %d. Waking on %d jiffies\n",
					dma_q->frame-old,dma_q->frame,timeout);
		} else
			dprintk(1,"will sleep for %i jiffies\n",timeout);

		vivi_thread_tick(dma_q);

		schedule_timeout_interruptible (timeout);
	}

	remove_wait_queue(&dma_q->wq, &wait);
	try_to_freeze();
}

static int vivi_thread(void *data)
{
	struct vivi_dmaqueue  *dma_q=data;

	dprintk(1,"thread started\n");

	mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
	set_freezable();

	for (;;) {
		vivi_sleep(dma_q);

		if (kthread_should_stop())
			break;
	}
	dprintk(1, "thread: exit\n");
	return 0;
}

static int vivi_start_thread(struct vivi_dmaqueue  *dma_q)
{
	dma_q->frame=0;
	dma_q->ini_jiffies=jiffies;

	dprintk(1,"%s\n",__FUNCTION__);

	dma_q->kthread = kthread_run(vivi_thread, dma_q, "vivi");

	if (IS_ERR(dma_q->kthread)) {
		printk(KERN_ERR "vivi: kernel_thread() failed\n");
		return PTR_ERR(dma_q->kthread);
	}
	/* Wakes thread */
	wake_up_interruptible(&dma_q->wq);

	dprintk(1,"returning from %s\n",__FUNCTION__);
	return 0;
}

static void vivi_stop_thread(struct vivi_dmaqueue  *dma_q)
{
	dprintk(1,"%s\n",__FUNCTION__);
	/* shutdown control thread */
	if (dma_q->kthread) {
		kthread_stop(dma_q->kthread);
		dma_q->kthread=NULL;
	}
}

static int restart_video_queue(struct vivi_dmaqueue *dma_q)
{
	struct vivi_buffer *buf, *prev;

	dprintk(1,"%s dma_q=0x%08lx\n",__FUNCTION__,(unsigned long)dma_q);

	if (!list_empty(&dma_q->active)) {
		buf = list_entry(dma_q->active.next, struct vivi_buffer, vb.queue);
		dprintk(2,"restart_queue [%p/%d]: restart dma\n",
			buf, buf->vb.i);

		dprintk(1,"Restarting video dma\n");
		vivi_stop_thread(dma_q);
//		vivi_start_thread(dma_q);

		/* cancel all outstanding capture / vbi requests */
		list_for_each_entry_safe(buf, prev, &dma_q->active, vb.queue) {
			list_del(&buf->vb.queue);
			buf->vb.state = STATE_ERROR;
			wake_up(&buf->vb.done);
		}
		mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);

		return 0;
	}

	prev = NULL;
	for (;;) {
		if (list_empty(&dma_q->queued))
			return 0;
		buf = list_entry(dma_q->queued.next, struct vivi_buffer, vb.queue);
		if (NULL == prev) {
			list_del(&buf->vb.queue);
			list_add_tail(&buf->vb.queue,&dma_q->active);

			dprintk(1,"Restarting video dma\n");
			vivi_stop_thread(dma_q);
			vivi_start_thread(dma_q);

			buf->vb.state = STATE_ACTIVE;
			mod_timer(&dma_q->timeout, jiffies+BUFFER_TIMEOUT);
			dprintk(2,"[%p/%d] restart_queue - first active\n",
				buf,buf->vb.i);

		} else if (prev->vb.width  == buf->vb.width  &&
			   prev->vb.height == buf->vb.height &&
			   prev->fmt       == buf->fmt) {
			list_del(&buf->vb.queue);
			list_add_tail(&buf->vb.queue,&dma_q->active);
			buf->vb.state = STATE_ACTIVE;
			dprintk(2,"[%p/%d] restart_queue - move to active\n",
				buf,buf->vb.i);
		} else {
			return 0;
		}
		prev = buf;
	}
}

static void vivi_vid_timeout(unsigned long data)
{
	struct vivi_dev      *dev  = (struct vivi_dev*)data;
	struct vivi_dmaqueue *vidq = &dev->vidq;
	struct vivi_buffer   *buf;

	while (!list_empty(&vidq->active)) {
		buf = list_entry(vidq->active.next, struct vivi_buffer, vb.queue);
		list_del(&buf->vb.queue);
		buf->vb.state = STATE_ERROR;
		wake_up(&buf->vb.done);
		printk("vivi/0: [%p/%d] timeout\n", buf, buf->vb.i);
	}

	restart_video_queue(vidq);
}

/* ------------------------------------------------------------------
	Videobuf operations
   ------------------------------------------------------------------*/
static int
buffer_setup(struct videobuf_queue *vq, unsigned int *count, unsigned int *size)
{
	struct vivi_fh *fh = vq->priv_data;

	*size = fh->width*fh->height*2;

	if (0 == *count)
		*count = 32;

	while (*size * *count > vid_limit * 1024 * 1024)
		(*count)--;

	dprintk(1,"%s, count=%d, size=%d\n",__FUNCTION__,*count, *size);

	return 0;
}

static void free_buffer(struct videobuf_queue *vq, struct vivi_buffer *buf)
{
	dprintk(1,"%s\n",__FUNCTION__);