videobuf-dvb.c

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/*
 *
 * some helper function for simple DVB cards which simply DMA the
 * complete transport stream and let the computer sort everything else
 * (i.e. we are using the software demux, ...).  Also uses the
 * video-buf to manage DMA buffers.
 *
 * (c) 2004 Gerd Knorr <[email protected]> [SUSE Labs]
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/kthread.h>
#include <linux/file.h>
#include <linux/slab.h>

#include <linux/freezer.h>

#include <media/videobuf-core.h>
#include <media/videobuf-dvb.h>

/* ------------------------------------------------------------------ */

MODULE_AUTHOR("Gerd Knorr <[email protected]> [SuSE Labs]");
MODULE_LICENSE("GPL");

static unsigned int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug,"enable debug messages");

#define dprintk(fmt, arg...)    if (debug)          \
    printk(KERN_DEBUG "%s/dvb: " fmt, dvb->name , ## arg)

/* ------------------------------------------------------------------ */

static int videobuf_dvb_thread(void *data)
{
    struct videobuf_dvb *dvb = data;
    struct videobuf_buffer *buf;
    unsigned long flags;
    void *outp;

    dprintk("dvb thread started\n");
    set_freezable();
    videobuf_read_start(&dvb->dvbq);

    for (;;) {
        /* fetch next buffer */
        buf = list_entry(dvb->dvbq.stream.next,
                 struct videobuf_buffer, stream);
        list_del(&buf->stream);
        videobuf_waiton(&dvb->dvbq, buf, 0, 1);

        /* no more feeds left or stop_feed() asked us to quit */
        if (0 == dvb->nfeeds)
            break;
        if (kthread_should_stop())
            break;
        try_to_freeze();

        /* feed buffer data to demux */
        outp = videobuf_queue_to_vaddr(&dvb->dvbq, buf);

        if (buf->state == VIDEOBUF_DONE)
            dvb_dmx_swfilter(&dvb->demux, outp,
                     buf->size);

        /* requeue buffer */
        list_add_tail(&buf->stream,&dvb->dvbq.stream);
        spin_lock_irqsave(dvb->dvbq.irqlock,flags);
        dvb->dvbq.ops->buf_queue(&dvb->dvbq,buf);
        spin_unlock_irqrestore(dvb->dvbq.irqlock,flags);
    }

    videobuf_read_stop(&dvb->dvbq);
    dprintk("dvb thread stopped\n");

    /* Hmm, linux becomes *very* unhappy without this ... */
    while (!kthread_should_stop()) {
        set_current_state(TASK_INTERRUPTIBLE);
        schedule();
    }
    return 0;
}

static int videobuf_dvb_start_feed(struct dvb_demux_feed *feed)
{
    struct dvb_demux *demux  = feed->demux;
    struct videobuf_dvb *dvb = demux->priv;
    int rc;

    if (!demux->dmx.frontend)
        return -EINVAL;

    mutex_lock(&dvb->lock);
    dvb->nfeeds++;
    rc = dvb->nfeeds;

    if (NULL != dvb->thread)
        goto out;
    dvb->thread = kthread_run(videobuf_dvb_thread,
                  dvb, "%s dvb", dvb->name);
    if (IS_ERR(dvb->thread)) {
        rc = PTR_ERR(dvb->thread);
        dvb->thread = NULL;
    }

out:
    mutex_unlock(&dvb->lock);
    return rc;
}

static int videobuf_dvb_stop_feed(struct dvb_demux_feed *feed)
{
    struct dvb_demux *demux  = feed->demux;
    struct videobuf_dvb *dvb = demux->priv;
    int err = 0;

    mutex_lock(&dvb->lock);
    dvb->nfeeds--;
    if (0 == dvb->nfeeds  &&  NULL != dvb->thread) {
        err = kthread_stop(dvb->thread);
        dvb->thread = NULL;
    }
    mutex_unlock(&dvb->lock);
    return err;
}

static int videobuf_dvb_register_adapter(struct videobuf_dvb_frontends *fe,
              struct module *module,
              void *adapter_priv,
              struct device *device,
              char *adapter_name,
              short *adapter_nr,
              int mfe_shared)
{
    int result;

    mutex_init(&fe->lock);

    /* register adapter */
    result = dvb_register_adapter(&fe->adapter, adapter_name, module,
        device, adapter_nr);
    if (result < 0) {
        printk(KERN_WARNING "%s: dvb_register_adapter failed (errno = %d)\n",
               adapter_name, result);
    }
    fe->adapter.priv = adapter_priv;
    fe->adapter.mfe_shared = mfe_shared;

    return result;
}

static int videobuf_dvb_register_frontend(struct dvb_adapter *adapter,
    struct videobuf_dvb *dvb)
{
    int result;

    /* register frontend */
    result = dvb_register_frontend(adapter, dvb->frontend);
    if (result < 0) {
        printk(KERN_WARNING "%s: dvb_register_frontend failed (errno = %d)\n",
               dvb->name, result);
        goto fail_frontend;
    }

    /* register demux stuff */
    dvb->demux.dmx.capabilities =
        DMX_TS_FILTERING | DMX_SECTION_FILTERING |
        DMX_MEMORY_BASED_FILTERING;
    dvb->demux.priv       = dvb;
    dvb->demux.filternum  = 256;
    dvb->demux.feednum    = 256;
    dvb->demux.start_feed = videobuf_dvb_start_feed;
    dvb->demux.stop_feed  = videobuf_dvb_stop_feed;
    result = dvb_dmx_init(&dvb->demux);
    if (result < 0) {
        printk(KERN_WARNING "%s: dvb_dmx_init failed (errno = %d)\n",
               dvb->name, result);
        goto fail_dmx;
    }

    dvb->dmxdev.filternum    = 256;
    dvb->dmxdev.demux        = &dvb->demux.dmx;
    dvb->dmxdev.capabilities = 0;
    result = dvb_dmxdev_init(&dvb->dmxdev, adapter);

    if (result < 0) {
        printk(KERN_WARNING "%s: dvb_dmxdev_init failed (errno = %d)\n",
               dvb->name, result);
        goto fail_dmxdev;
    }

    dvb->fe_hw.source = DMX_FRONTEND_0;
    result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_hw);
    if (result < 0) {
        printk(KERN_WARNING "%s: add_frontend failed (DMX_FRONTEND_0, errno = %d)\n",
               dvb->name, result);
        goto fail_fe_hw;
    }

    dvb->fe_mem.source = DMX_MEMORY_FE;
    result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_mem);
    if (result < 0) {
        printk(KERN_WARNING "%s: add_frontend failed (DMX_MEMORY_FE, errno = %d)\n",
               dvb->name, result);
        goto fail_fe_mem;
    }

    result = dvb->demux.dmx.connect_frontend(&dvb->demux.dmx, &dvb->fe_hw);
    if (result < 0) {
        printk(KERN_WARNING "%s: connect_frontend failed (errno = %d)\n",
               dvb->name, result);
        goto fail_fe_conn;
    }

    /* register network adapter */
    result = dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
    if (result < 0) {
        printk(KERN_WARNING "%s: dvb_net_init failed (errno = %d)\n",
               dvb->name, result);
        goto fail_fe_conn;
    }
    return 0;

fail_fe_conn:
    dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
fail_fe_mem:
    dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
fail_fe_hw:
    dvb_dmxdev_release(&dvb->dmxdev);
fail_dmxdev:
    dvb_dmx_release(&dvb->demux);
fail_dmx:
    dvb_unregister_frontend(dvb->frontend);
fail_frontend:
    dvb_frontend_detach(dvb->frontend);
    dvb->frontend = NULL;

    return result;
}

/* ------------------------------------------------------------------ */
/* Register a single adapter and one or more frontends */
int videobuf_dvb_register_bus(struct videobuf_dvb_frontends *f,
              struct module *module,
              void *adapter_priv,
              struct device *device,
              short *adapter_nr,
              int mfe_shared)
{
    struct list_head *list, *q;
    struct videobuf_dvb_frontend *fe;
    int res;

    fe = videobuf_dvb_get_frontend(f, 1);
    if (!fe) {
        printk(KERN_WARNING "Unable to register the adapter which has no frontends\n");
        return -EINVAL;
    }

    /* Bring up the adapter */
    res = videobuf_dvb_register_adapter(f, module, adapter_priv, device,
        fe->dvb.name, adapter_nr, mfe_shared);
    if (res < 0) {
        printk(KERN_WARNING "videobuf_dvb_register_adapter failed (errno = %d)\n", res);
        return res;
    }

    /* Attach all of the frontends to the adapter */
    mutex_lock(&f->lock);
    list_for_each_safe(list, q, &f->felist) {
        fe = list_entry(list, struct videobuf_dvb_frontend, felist);
        res = videobuf_dvb_register_frontend(&f->adapter, &fe->dvb);
        if (res < 0) {
            printk(KERN_WARNING "%s: videobuf_dvb_register_frontend failed (errno = %d)\n",
                fe->dvb.name, res);
            goto err;
        }
    }
    mutex_unlock(&f->lock);
    return 0;

err:
    mutex_unlock(&f->lock);
    videobuf_dvb_unregister_bus(f);
    return res;
}
EXPORT_SYMBOL(videobuf_dvb_register_bus);

void videobuf_dvb_unregister_bus(struct videobuf_dvb_frontends *f)
{
    videobuf_dvb_dealloc_frontends(f);

    dvb_unregister_adapter(&f->adapter);
}
EXPORT_SYMBOL(videobuf_dvb_unregister_bus);

struct videobuf_dvb_frontend *videobuf_dvb_get_frontend(
    struct videobuf_dvb_frontends *f, int id)
{
    struct list_head *list, *q;
    struct videobuf_dvb_frontend *fe, *ret = NULL;

    mutex_lock(&f->lock);

    list_for_each_safe(list, q, &f->felist) {
        fe = list_entry(list, struct videobuf_dvb_frontend, felist);
        if (fe->id == id) {
            ret = fe;
            break;
        }
    }

    mutex_unlock(&f->lock);

    return ret;
}
EXPORT_SYMBOL(videobuf_dvb_get_frontend);

int videobuf_dvb_find_frontend(struct videobuf_dvb_frontends *f,
    struct dvb_frontend *p)
{
    struct list_head *list, *q;
    struct videobuf_dvb_frontend *fe = NULL;
    int ret = 0;

    mutex_lock(&f->lock);

    list_for_each_safe(list, q, &f->felist) {
        fe = list_entry(list, struct videobuf_dvb_frontend, felist);
        if (fe->dvb.frontend == p) {
            ret = fe->id;
            break;
        }
    }

    mutex_unlock(&f->lock);

    return ret;
}
EXPORT_SYMBOL(videobuf_dvb_find_frontend);

struct videobuf_dvb_frontend *videobuf_dvb_alloc_frontend(
    struct videobuf_dvb_frontends *f, int id)
{
    struct videobuf_dvb_frontend *fe;

    fe = kzalloc(sizeof(struct videobuf_dvb_frontend), GFP_KERNEL);
    if (fe == NULL)
        goto fail_alloc;

    fe->id = id;
    mutex_init(&fe->dvb.lock);

    mutex_lock(&f->lock);
    list_add_tail(&fe->felist, &f->felist);
    mutex_unlock(&f->lock);

fail_alloc:
    return fe;
}
EXPORT_SYMBOL(videobuf_dvb_alloc_frontend);

void videobuf_dvb_dealloc_frontends(struct videobuf_dvb_frontends *f)
{
    struct list_head *list, *q;
    struct videobuf_dvb_frontend *fe;

    mutex_lock(&f->lock);
    list_for_each_safe(list, q, &f->felist) {
        fe = list_entry(list, struct videobuf_dvb_frontend, felist);
        if (fe->dvb.net.dvbdev) {
            dvb_net_release(&fe->dvb.net);
            fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
                &fe->dvb.fe_mem);
            fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
                &fe->dvb.fe_hw);
            dvb_dmxdev_release(&fe->dvb.dmxdev);
            dvb_dmx_release(&fe->dvb.demux);
            dvb_unregister_frontend(fe->dvb.frontend);
        }
        if (fe->dvb.frontend)
            /* always allocated, may have been reset */
            dvb_frontend_detach(fe->dvb.frontend);
        list_del(list); /* remove list entry */
        kfree(fe);  /* free frontend allocation */
    }
    mutex_unlock(&f->lock);
}
EXPORT_SYMBOL(videobuf_dvb_dealloc_frontends);