dvb_frontend.c

dvb的系统程序。基于lunix系统.经过改进更新

/*
 * dvb-core.c: DVB core driver
 *
 * Copyright (C) 1999-2001 Ralph  Metzler
 *                         Marcus Metzler
 *                         Holger Waechtler 
 *                                    for convergence integrated media GmbH
 * 
 * Copyright (C) 2004 Andrew de Quincey (tuning thread cleanup)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * 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 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.
 * Or, point your browser to http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/module.h>
#include <linux/list.h>
#include <asm/processor.h>
#include <asm/semaphore.h>

#include "dvb_frontend.h"
#include "dvbdev.h"
#include "dvb_functions.h"

#define FESTATE_IDLE 1
#define FESTATE_RETUNE 2
#define FESTATE_TUNING_FAST 4
#define FESTATE_TUNING_SLOW 8
#define FESTATE_TUNED 16
#define FESTATE_ZIGZAG_FAST 32
#define FESTATE_ZIGZAG_SLOW 64
#define FESTATE_CLEAN_SETUP 128
#define FESTATE_SEARCHING (FESTATE_TUNING_FAST | FESTATE_TUNING_SLOW | FESTATE_ZIGZAG_FAST | FESTATE_ZIGZAG_SLOW)
#define FESTATE_SEARCHING_FAST (FESTATE_TUNING_FAST | FESTATE_ZIGZAG_FAST)
#define FESTATE_SEARCHING_SLOW (FESTATE_TUNING_SLOW | FESTATE_ZIGZAG_SLOW)
#define FESTATE_LOSTLOCK (FESTATE_ZIGZAG_FAST | FESTATE_ZIGZAG_SLOW)
/*
 * FESTATE_IDLE. No tuning parameters have been supplied and the loop is idling.
 * FESTATE_RETUNE. Parameters have been supplied, but we have not yet performed the first tune.
 * FESTATE_TUNING_FAST. Tuning parameters have been supplied and fast zigzag scan is in progress.
 * FESTATE_TUNING_SLOW. Tuning parameters have been supplied. Fast zigzag failed, so we're trying again, but slower.
 * FESTATE_TUNED. The frontend has successfully locked on.
 * FESTATE_ZIGZAG_FAST. The lock has been lost, and a fast zigzag has been initiated to try and regain it.
 * FESTATE_ZIGZAG_SLOW. The lock has been lost. Fast zigzag has been failed, so we're trying again, but slower.
 * FESTATE_CLEAN_SETUP. Used for certain dodgy tuners which need special massaging to lock.
 * FESTATE_SEARCHING. When we're searching for a signal using a zigzag scan of any sort.
 * FESTATE_SEARCHING_FAST. When we're searching for a signal using a fast zigzag scan.
 * FESTATE_SEARCHING_SLOW. When we're searching for a signal using a slow zigzag scan.
 * FESTATE_LOSTLOCK. When the lock has been lost, and we're searching it again.
 */


static int dvb_frontend_debug = 0;
static int dvb_shutdown_timeout = 5;
static int dvb_frequency_bending = 1;

#define dprintk if (dvb_frontend_debug) printk

#define MAX_EVENT 8

struct dvb_fe_events {
	struct dvb_frontend_event events[MAX_EVENT];
	int                       eventw;
	int                       eventr;
	int                       overflow;
	wait_queue_head_t         wait_queue;
	struct semaphore          sem;
};


struct dvb_frontend_data {
	struct dvb_frontend_info *info;
	struct dvb_frontend frontend;
	struct dvb_device *dvbdev;
	struct dvb_frontend_parameters parameters;
	struct dvb_fe_events events;
	struct semaphore sem;
	struct list_head list_head;
	wait_queue_head_t wait_queue;
	pid_t thread_pid;
	unsigned long release_jiffies;
        int state;
	int bending;
	int lnb_drift;
        int inversion;
        int auto_count;
        int started_auto_count;
        int min_delay;
	int exit;
        fe_status_t status;
};


struct dvb_frontend_ioctl_data {
	struct list_head list_head;
	struct dvb_adapter *adapter;
	int (*before_ioctl) (struct dvb_frontend *frontend,
			     unsigned int cmd, void *arg);
	int (*after_ioctl)  (struct dvb_frontend *frontend,
			     unsigned int cmd, void *arg);
	void *before_after_data;
};


struct dvb_frontend_notifier_data {
	struct list_head list_head;
	struct dvb_adapter *adapter;
	void (*callback) (fe_status_t s, void *data);
	void *data;
};


static LIST_HEAD(frontend_list);
static LIST_HEAD(frontend_ioctl_list);
static LIST_HEAD(frontend_notifier_list);

static DECLARE_MUTEX(frontend_mutex);


static int dvb_frontend_internal_ioctl (struct dvb_frontend *frontend, 
				 unsigned int cmd, void *arg)
{
	int err = -EOPNOTSUPP;

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

	if (frontend->before_ioctl)
		err = frontend->before_ioctl (frontend, cmd, arg);

	if (err == -EOPNOTSUPP) {
		err = frontend->ioctl (frontend, cmd, arg);

		if ((err == -EOPNOTSUPP) && frontend->after_ioctl)
			err = frontend->after_ioctl (frontend, cmd, arg);
	}

	return err;
}


/**
 *  if 2 tuners are located side by side you can get interferences when
 *  they try to tune to the same frequency, so both lose sync.
 *  We will slightly mistune in this case. The AFC of the demodulator
 *  should make it still possible to receive the requested transponder 
 *  on both tuners...
 */
static void dvb_bend_frequency (struct dvb_frontend_data *this_fe, int recursive)
{
	struct list_head *entry;
	int stepsize = this_fe->info->frequency_stepsize;
	int this_fe_adap_num = this_fe->frontend.i2c->adapter->num;
	int frequency;

	if (!stepsize || recursive > 10) {
		printk ("%s: too deep recursion, check frequency_stepsize "
			"in your frontend code!\n", __FUNCTION__);
		return;
	}

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

	if (!recursive) {
		if (down_interruptible (&frontend_mutex))
			return;

		this_fe->bending = 0;
	}

	list_for_each (entry, &frontend_list) {
		struct dvb_frontend_data *fe;
		int f;

		fe = list_entry (entry, struct dvb_frontend_data, list_head);

		if (fe->frontend.i2c->adapter->num != this_fe_adap_num)
			continue;

		f = fe->parameters.frequency;
		f += fe->lnb_drift;
		f += fe->bending;

		frequency = this_fe->parameters.frequency;
		frequency += this_fe->lnb_drift;
		frequency += this_fe->bending;

		if (this_fe != fe && (fe->state != FESTATE_IDLE) &&
                    frequency > f - stepsize && frequency < f + stepsize)
		{
			if (recursive % 2)
				this_fe->bending += stepsize;
			else
				this_fe->bending = -this_fe->bending;

			dvb_bend_frequency (this_fe, recursive + 1);
			goto done;
		}
	}
done:
	if (!recursive)
		up (&frontend_mutex);
}


static void dvb_call_frontend_notifiers (struct dvb_frontend_data *fe,
				  fe_status_t s)
{
	dprintk ("%s\n", __FUNCTION__);

	if (((s ^ fe->status) & FE_HAS_LOCK) && (s & FE_HAS_LOCK))
		dvb_delay (fe->info->notifier_delay);

	fe->status = s;

	if (!(s & FE_HAS_LOCK) && (fe->info->caps & FE_CAN_MUTE_TS))
		return;

	/**
	 *   now tell the Demux about the TS status changes...
	 */
	if (fe->frontend.notifier_callback)
		fe->frontend.notifier_callback(fe->status, fe->frontend.notifier_data);
}


static void dvb_frontend_add_event (struct dvb_frontend_data *fe, fe_status_t status)
{
	struct dvb_fe_events *events = &fe->events;
	struct dvb_frontend_event *e;
	int wp;

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

	if (down_interruptible (&events->sem))
		return;

	wp = (events->eventw + 1) % MAX_EVENT;

	if (wp == events->eventr) {
		events->overflow = 1;
		events->eventr = (events->eventr + 1) % MAX_EVENT;
	}

	e = &events->events[events->eventw];

	memcpy (&e->parameters, &fe->parameters, 
		sizeof (struct dvb_frontend_parameters));

	if (status & FE_HAS_LOCK)
		dvb_frontend_internal_ioctl (&fe->frontend,
					     FE_GET_FRONTEND,
					     &e->parameters);
	events->eventw = wp;

	up (&events->sem);

	e->status = status;
	dvb_call_frontend_notifiers (fe, status);

	wake_up_interruptible (&events->wait_queue);
}


static int dvb_frontend_get_event (struct dvb_frontend_data *fe,
			    struct dvb_frontend_event *event, int flags)
{
        struct dvb_fe_events *events = &fe->events;

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

	if (events->overflow) {
                events->overflow = 0;
                return -EOVERFLOW;
        }

        if (events->eventw == events->eventr) {
		int ret;

                if (flags & O_NONBLOCK)
                        return -EWOULDBLOCK;

		up(&fe->sem);

                ret = wait_event_interruptible (events->wait_queue,
                                                events->eventw != events->eventr);

        	if (down_interruptible (&fe->sem))
			return -ERESTARTSYS;

                if (ret < 0)
                        return ret;
        }

        if (down_interruptible (&events->sem))
		return -ERESTARTSYS;

       	memcpy (event, &events->events[events->eventr],
		sizeof(struct dvb_frontend_event));

        events->eventr = (events->eventr + 1) % MAX_EVENT;

       	up (&events->sem);

        return 0;
}

static void dvb_frontend_init (struct dvb_frontend_data *fe)
{
	struct dvb_frontend *frontend = &fe->frontend;

	dprintk ("DVB: initialising frontend %i:%i (%s)...\n",
		 frontend->i2c->adapter->num, frontend->i2c->id,
		 fe->info->name);

	dvb_frontend_internal_ioctl (frontend, FE_INIT, NULL);
}

static void update_delay (int *quality, int *delay, int min_delay, int locked)
{
            int q2;
    
            dprintk ("%s\n", __FUNCTION__);
    
            if (locked)
                      (*quality) = (*quality * 220 + 36*256) / 256;
            else
                      (*quality) = (*quality * 220 + 0) / 256;
    
            q2 = *quality - 128;
            q2 *= q2;
    
            *delay = min_delay + q2 * HZ / (128*128);
}

/**
 * Performs automatic twiddling of frontend parameters.
 * 
 * @param fe The frontend concerned.
 * @returns Number of complete iterations that have been performed.
 */
static int dvb_frontend_autotune(struct dvb_frontend_data *fe)
{
        int stepsize;
        int maxdrift;
        int autoinversion;
        int ready = 0;
        int wrapped = 0;
        int original_inversion = fe->parameters.inversion;
        u32 original_frequency = fe->parameters.frequency;

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

        // choose step size for zigzag scan
	switch(fe->info->type) {
	case FE_QPSK:
	        if (fe->parameters.u.qpsk.symbol_rate < 10000000) {
	                stepsize = fe->parameters.u.qpsk.symbol_rate / 32000;
	                maxdrift = 5000;
	        } else {
		        stepsize = fe->parameters.u.qpsk.symbol_rate / 16000;
		        maxdrift = fe->parameters.u.qpsk.symbol_rate / 2000;
		}
	        break;
	    
	case FE_QAM:
		stepsize = 1;
	        maxdrift = 0; // don't want any zigzagging under DVB-C frontends
	        break;
	    
	case FE_OFDM:
	        stepsize = fe->info->frequency_stepsize * 2;
	        maxdrift = (fe->info->frequency_stepsize * 2) + 1;
	        break;