dmxdev.c

linux环境下的dvb驱动程序

/* 
 * dmxdev.c - DVB demultiplexer device 
 *
 * Copyright (C) 2000 Ralph  Metzler <[e-mail]>
 *		  & Marcus Metzler <[e-mail]>
		      for convergence integrated media GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/poll.h>
#include <linux/ioctl.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
#include <asm/system.h>

#include "dmxdev.h"
#include "dvb_functions.h"

MODULE_PARM(debug,"i");
static int debug = 0;

#define dprintk	if (debug) printk

inline struct dmxdev_filter *
dvb_dmxdev_file_to_filter(struct file *file)
{
	return (struct dmxdev_filter *) file->private_data;
}

inline struct dmxdev_dvr *
dvb_dmxdev_file_to_dvr(struct dmxdev *dmxdev, struct file *file)
{
	return (struct dmxdev_dvr *) file->private_data;
}

static inline void dvb_dmxdev_buffer_init(struct dmxdev_buffer *buffer) 
{
	buffer->data=0;
	buffer->size=8192;
	buffer->pread=0;
	buffer->pwrite=0;
	buffer->error=0;
	init_waitqueue_head(&buffer->queue);
}

static inline int dvb_dmxdev_buffer_write(struct dmxdev_buffer *buf, const u8 *src, int len) 
{
	int split;
	int free;
	int todo;

	if (!len)
		return 0;
	if (!buf->data)
		return 0;
	
	free=buf->pread-buf->pwrite;
	split=0;
	if (free<=0) {
		free+=buf->size;
		split=buf->size-buf->pwrite;
	}
	if (len>=free) {
		dprintk("dmxdev: buffer overflow\n");
		return -1;
	}
	if (split>=len)
		split=0;
	todo=len;
	if (split) {
		memcpy(buf->data + buf->pwrite, src, split);
		todo-=split;
		buf->pwrite=0;
	}
	memcpy(buf->data + buf->pwrite, src+split, todo);
	buf->pwrite=(buf->pwrite+todo)%buf->size;
	return len;
}

static ssize_t dvb_dmxdev_buffer_read(struct dmxdev_buffer *src,
		int non_blocking, char *buf, size_t count, loff_t *ppos)
{
	unsigned long todo=count;
	int split, avail, error;
	
	if (!src->data)
		return 0;

	if ((error=src->error)) {
		src->pwrite=src->pread;
		src->error=0;
		return error; 
	}

	if (non_blocking && (src->pwrite==src->pread))
		return -EWOULDBLOCK;

	while (todo>0) {
		if (non_blocking && (src->pwrite==src->pread))
			return (count-todo) ? (count-todo) : -EWOULDBLOCK;

		if (wait_event_interruptible(src->queue,
					     (src->pread!=src->pwrite) ||
					     (src->error))<0)
			return count-todo;

		if ((error=src->error)) {
			src->pwrite=src->pread;
			src->error=0;
			return error; 
		}
		
		split=src->size;
		avail=src->pwrite - src->pread;
		if (avail<0) {
			avail+=src->size;
			split=src->size - src->pread;
		}
		if (avail>todo)
			avail=todo;
		if (split<avail) {
			if (copy_to_user(buf, src->data+src->pread, split))
				  return -EFAULT;
			buf+=split;
			src->pread=0;
			todo-=split;
			avail-=split;
		}
		if (avail) {
			if (copy_to_user(buf, src->data+src->pread, avail))
				return -EFAULT;
			src->pread = (src->pread + avail) % src->size;
			todo-=avail;
			buf+=avail;
		}
	}
	return count;
}

static struct dmx_frontend * get_fe(struct dmx_demux *demux, int type)
{
	struct list_head *head, *pos;

	head=demux->get_frontends(demux);
	if (!head)
		return 0;
	list_for_each(pos, head)
		if (DMX_FE_ENTRY(pos)->source==type)
			return DMX_FE_ENTRY(pos);
	
	return 0;
}

static inline void dvb_dmxdev_dvr_state_set(struct dmxdev_dvr *dmxdevdvr, int state)
{
	spin_lock_irq(&dmxdevdvr->dev->lock);
	dmxdevdvr->state=state;
	spin_unlock_irq(&dmxdevdvr->dev->lock);
}

static int dvb_dvr_open(struct inode *inode, struct file *file)
{
	struct dvb_device *dvbdev=(struct dvb_device *) file->private_data;
	struct dmxdev *dmxdev=(struct dmxdev *) dvbdev->priv;
	struct dmx_frontend *front;

	dprintk ("function : %s\n", __FUNCTION__);

	if (down_interruptible (&dmxdev->mutex))
		return -ERESTARTSYS;
	
	if ((file->f_flags&O_ACCMODE)==O_RDWR) {
		if (!(dmxdev->capabilities&DMXDEV_CAP_DUPLEX)) {
			up(&dmxdev->mutex);
			return -EOPNOTSUPP;
		}
	}

	if ((file->f_flags&O_ACCMODE)==O_RDONLY) {
	      dvb_dmxdev_buffer_init(&dmxdev->dvr_buffer);
	      dmxdev->dvr_buffer.size=DVR_BUFFER_SIZE;
	      dmxdev->dvr_buffer.data=vmalloc(DVR_BUFFER_SIZE);
	      if (!dmxdev->dvr_buffer.data) {
		      up(&dmxdev->mutex);
		      return -ENOMEM;
	      }
	}

	if ((file->f_flags&O_ACCMODE)==O_WRONLY) {
		dmxdev->dvr_orig_fe=dmxdev->demux->frontend;
		
		if (!dmxdev->demux->write) {
			up(&dmxdev->mutex);
			return -EOPNOTSUPP;
		}
		
		front=get_fe(dmxdev->demux, DMX_MEMORY_FE);
		
		if (!front) {
			up(&dmxdev->mutex);
			return -EINVAL;
		}
		dmxdev->demux->disconnect_frontend(dmxdev->demux);	
		dmxdev->demux->connect_frontend(dmxdev->demux, front);	
	}
	up(&dmxdev->mutex);
	return 0;
}

static int dvb_dvr_release(struct inode *inode, struct file *file)
{
	struct dvb_device *dvbdev=(struct dvb_device *) file->private_data;
	struct dmxdev *dmxdev=(struct dmxdev *) dvbdev->priv;

	if (down_interruptible (&dmxdev->mutex))
		return -ERESTARTSYS;

	if ((file->f_flags&O_ACCMODE)==O_WRONLY) {
		dmxdev->demux->disconnect_frontend(dmxdev->demux);	
		dmxdev->demux->connect_frontend(dmxdev->demux, 
						dmxdev->dvr_orig_fe);
	}
	if ((file->f_flags&O_ACCMODE)==O_RDONLY) {
		if (dmxdev->dvr_buffer.data) {
			void *mem=dmxdev->dvr_buffer.data;
			mb();
			spin_lock_irq(&dmxdev->lock);
			dmxdev->dvr_buffer.data=0;
			spin_unlock_irq(&dmxdev->lock);
			vfree(mem);
		}
	}
	up(&dmxdev->mutex);
	return 0;
}

static ssize_t dvb_dvr_write(struct file *file, const char *buf,
		size_t count, loff_t *ppos)
{
	struct dvb_device *dvbdev=(struct dvb_device *) file->private_data;
	struct dmxdev *dmxdev=(struct dmxdev *) dvbdev->priv;
	int ret;

	if (!dmxdev->demux->write)
		return -EOPNOTSUPP;
	if ((file->f_flags&O_ACCMODE)!=O_WRONLY)
		return -EINVAL;
	if (down_interruptible (&dmxdev->mutex))
		return -ERESTARTSYS;
	ret=dmxdev->demux->write(dmxdev->demux, buf, count);
	up(&dmxdev->mutex);
	return ret;
}

static ssize_t dvb_dvr_read(struct file *file, char *buf, size_t count,
		loff_t *ppos)
{
	struct dvb_device *dvbdev=(struct dvb_device *) file->private_data;
	struct dmxdev *dmxdev=(struct dmxdev *) dvbdev->priv;
	int ret;

	//down(&dmxdev->mutex);
	ret= dvb_dmxdev_buffer_read(&dmxdev->dvr_buffer, 
			      file->f_flags&O_NONBLOCK, 
			      buf, count, ppos);
	//up(&dmxdev->mutex);
	return ret;
}

static inline void dvb_dmxdev_filter_state_set(struct dmxdev_filter *dmxdevfilter, int state)
{
	spin_lock_irq(&dmxdevfilter->dev->lock);
	dmxdevfilter->state=state;
	spin_unlock_irq(&dmxdevfilter->dev->lock);
}

static int dvb_dmxdev_set_buffer_size(struct dmxdev_filter *dmxdevfilter, unsigned long size)
{
	struct dmxdev_buffer *buf=&dmxdevfilter->buffer;
	void *mem;

	if (buf->size==size)
		return 0;
	if (dmxdevfilter->state>=DMXDEV_STATE_GO)
		return -EBUSY;
	spin_lock_irq(&dmxdevfilter->dev->lock);
	mem=buf->data;
	buf->data=0;
	buf->size=size;
	buf->pwrite=buf->pread=0;    
	spin_unlock_irq(&dmxdevfilter->dev->lock);
	if (mem) 
		vfree(mem);
		
	if (buf->size) {
		mem=vmalloc(dmxdevfilter->buffer.size);
		if (!mem)
			return -ENOMEM;
		spin_lock_irq(&dmxdevfilter->dev->lock);
		buf->data=mem;
		spin_unlock_irq(&dmxdevfilter->dev->lock);
	}
	return 0;
}

static void dvb_dmxdev_filter_timeout(unsigned long data)
{
	struct dmxdev_filter *dmxdevfilter=(struct dmxdev_filter *)data;
	
	dmxdevfilter->buffer.error=-ETIMEDOUT;
	spin_lock_irq(&dmxdevfilter->dev->lock);
	dmxdevfilter->state=DMXDEV_STATE_TIMEDOUT;
	spin_unlock_irq(&dmxdevfilter->dev->lock);
	wake_up(&dmxdevfilter->buffer.queue);
}

static void dvb_dmxdev_filter_timer(struct dmxdev_filter *dmxdevfilter)
{
	struct dmx_sct_filter_params *para=&dmxdevfilter->params.sec;
  
	del_timer(&dmxdevfilter->timer);
	if (para->timeout) {
		dmxdevfilter->timer.function=dvb_dmxdev_filter_timeout;
		dmxdevfilter->timer.data=(unsigned long) dmxdevfilter;
		dmxdevfilter->timer.expires=jiffies+1+(HZ/2+HZ*para->timeout)/1000;
		add_timer(&dmxdevfilter->timer);
	}
}

static int dvb_dmxdev_section_callback(const u8 *buffer1, size_t buffer1_len,
			    const u8 *buffer2, size_t buffer2_len,
			    struct dmx_section_filter *filter, enum dmx_success success)
{
	struct dmxdev_filter *dmxdevfilter=(struct dmxdev_filter *) filter->priv;
	int ret;
	
	if (dmxdevfilter->buffer.error) {
		wake_up(&dmxdevfilter->buffer.queue);
		return 0;
	}
	spin_lock(&dmxdevfilter->dev->lock);
	if (dmxdevfilter->state!=DMXDEV_STATE_GO) {
		spin_unlock(&dmxdevfilter->dev->lock);
		return 0;
	}
	del_timer(&dmxdevfilter->timer);
	dprintk("dmxdev: section callback %02x %02x %02x %02x %02x %02x\n", 
		buffer1[0], buffer1[1], 
		buffer1[2], buffer1[3], 
		buffer1[4], buffer1[5]);
	ret=dvb_dmxdev_buffer_write(&dmxdevfilter->buffer, buffer1, buffer1_len);
	if (ret==buffer1_len) {
		ret=dvb_dmxdev_buffer_write(&dmxdevfilter->buffer, buffer2, buffer2_len);
	}
	if (ret<0) {
		dmxdevfilter->buffer.pwrite=dmxdevfilter->buffer.pread;    
		dmxdevfilter->buffer.error=-EOVERFLOW;
	}
	if (dmxdevfilter->params.sec.flags&DMX_ONESHOT)
		dmxdevfilter->state=DMXDEV_STATE_DONE;
	spin_unlock(&dmxdevfilter->dev->lock);
	wake_up(&dmxdevfilter->buffer.queue);
	return 0;
}

static int dvb_dmxdev_ts_callback(const u8 *buffer1, size_t buffer1_len,
		       const u8 *buffer2, size_t buffer2_len,
		       struct dmx_ts_feed *feed, enum dmx_success success)
{
	struct dmxdev_filter *dmxdevfilter=(struct dmxdev_filter *) feed->priv;
	struct dmxdev_buffer *buffer;
	int ret;
	
	spin_lock(&dmxdevfilter->dev->lock);
	if (dmxdevfilter->params.pes.output==DMX_OUT_DECODER) {
		spin_unlock(&dmxdevfilter->dev->lock);
		return 0;
	}

	if (dmxdevfilter->params.pes.output==DMX_OUT_TAP)
		buffer=&dmxdevfilter->buffer;
	else
		buffer=&dmxdevfilter->dev->dvr_buffer;
	if (buffer->error) {
		spin_unlock(&dmxdevfilter->dev->lock);
		wake_up(&buffer->queue);
		return 0;
	}
	ret=dvb_dmxdev_buffer_write(buffer, buffer1, buffer1_len);
	if (ret==buffer1_len) 
		ret=dvb_dmxdev_buffer_write(buffer, buffer2, buffer2_len);
	if (ret<0) {
		buffer->pwrite=buffer->pread;    
		buffer->error=-EOVERFLOW;
	}
	spin_unlock(&dmxdevfilter->dev->lock);
	wake_up(&buffer->queue);
	return 0;
}


/* stop feed but only mark the specified filter as stopped (state set) */

static int dvb_dmxdev_feed_stop(struct dmxdev_filter *dmxdevfilter)
{
	dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_SET);

	switch (dmxdevfilter->type) {
	case DMXDEV_TYPE_SEC:
		del_timer(&dmxdevfilter->timer);
		dmxdevfilter->feed.sec->stop_filtering(dmxdevfilter->feed.sec);
		break;
	case DMXDEV_TYPE_PES:
		dmxdevfilter->feed.ts->stop_filtering(dmxdevfilter->feed.ts);
		break;
	default:
		return -EINVAL;
	}
	return 0;
}


/* start feed associated with the specified filter */

static int dvb_dmxdev_feed_start(struct dmxdev_filter *filter)
{
	dvb_dmxdev_filter_state_set (filter, DMXDEV_STATE_GO);

	switch (filter->type) {
	case DMXDEV_TYPE_SEC:
		return filter->feed.sec->start_filtering(filter->feed.sec);
		break;
	case DMXDEV_TYPE_PES:
		return filter->feed.ts->start_filtering(filter->feed.ts);
		break;
	default:
		return -EINVAL;
	}

	return 0;
}


/* restart section feed if it has filters left associated with it, 
   otherwise release the feed */

static int dvb_dmxdev_feed_restart(struct dmxdev_filter *filter)
{
	int i;
	struct dmxdev *dmxdev = filter->dev;
	u16 pid = filter->params.sec.pid;
	
	for (i=0; i<dmxdev->filternum; i++) 
		if (dmxdev->filter[i].state>=DMXDEV_STATE_GO &&
		    dmxdev->filter[i].type==DMXDEV_TYPE_SEC &&
		    dmxdev->filter[i].pid==pid) {
			dvb_dmxdev_feed_start(&dmxdev->filter[i]);
			return 0;
		}
	
	filter->dev->demux->release_section_feed(dmxdev->demux, filter->feed.sec);

	return 0;
}

static int dvb_dmxdev_filter_stop(struct dmxdev_filter *dmxdevfilter)
{
	if (dmxdevfilter->state<DMXDEV_STATE_GO) 
		return 0;

	switch (dmxdevfilter->type) {
	case DMXDEV_TYPE_SEC:
		if (!dmxdevfilter->feed.sec)
			break;
		dvb_dmxdev_feed_stop(dmxdevfilter);
		if (dmxdevfilter->filter.sec)
			dmxdevfilter->feed.sec->
				release_filter(dmxdevfilter->feed.sec,
					       dmxdevfilter->filter.sec);
		dvb_dmxdev_feed_restart(dmxdevfilter);
		dmxdevfilter->feed.sec=0;
		break;
	case DMXDEV_TYPE_PES:
		if (!dmxdevfilter->feed.ts)
			break;
		dvb_dmxdev_feed_stop(dmxdevfilter);
		dmxdevfilter->dev->demux->
			release_ts_feed(dmxdevfilter->dev->demux,
					dmxdevfilter->feed.ts);
		dmxdevfilter->feed.ts=0;
		break;
	default:
		if (dmxdevfilter->state==DMXDEV_STATE_ALLOCATED) 
			return 0;
		return -EINVAL;
	}
	dmxdevfilter->buffer.pwrite=dmxdevfilter->buffer.pread=0;    
	return 0;
}

static inline int dvb_dmxdev_filter_reset(struct dmxdev_filter *dmxdevfilter)
{
	if (dmxdevfilter->state<DMXDEV_STATE_SET) 
		return 0;

	dmxdevfilter->type=DMXDEV_TYPE_NONE;
	dmxdevfilter->pid=0xffff;
	dvb_dmxdev_filter_state_set(dmxdevfilter, DMXDEV_STATE_ALLOCATED);
	return 0;
}

static int dvb_dmxdev_filter_start(struct dmxdev_filter *filter)
{
	struct dmxdev *dmxdev = filter->dev;
	void *mem;
	int ret, i;

	if (filter->state < DMXDEV_STATE_SET) 
		return -EINVAL;

	if (filter->state >= DMXDEV_STATE_GO)
		dvb_dmxdev_filter_stop(filter); 

	if (!(mem = filter->buffer.data)) {
		mem = vmalloc(filter->buffer.size);
		spin_lock_irq(&filter->dev->lock);
		filter->buffer.data=mem;
		spin_unlock_irq(&filter->dev->lock);
		if (!filter->buffer.data)
			return -ENOMEM;
	}

	filter->buffer.pwrite = filter->buffer.pread = 0;

	switch (filter->type) {
	case DMXDEV_TYPE_SEC:
	{
		struct dmx_sct_filter_params *para=&filter->params.sec;
		struct dmx_section_filter **secfilter=&filter->filter.sec;
		struct dmx_section_feed **secfeed=&filter->feed.sec;

		*secfilter=0;
		*secfeed=0;

		/* find active filter/feed with same PID */
		for (i=0; i<dmxdev->filternum; i++) {
			if (dmxdev->filter[i].state >= DMXDEV_STATE_GO &&
			    dmxdev->filter[i].pid == para->pid && 
			    dmxdev->filter[i].type == DMXDEV_TYPE_SEC) {
				*secfeed = dmxdev->filter[i].feed.sec;
				break;
			}
		}

		/* if no feed found, try to allocate new one */