dvb_ca.c

linux_dvb的驱动程序：linuxtv-dvb-1.1.1.rar

        return packet_size;
}




/* ******************************************************************************** */
/* File IO interface functions */




/**
 * Implementation of file open syscall.
 *
 * @param inode Inode concerned.
 * @param file File concerned.
 *
 * @return 0 on success, <0 on failure.
 */
int dvb_ca_io_open(struct inode *inode, struct file *file) {
        dvb_device_t *dvbdev=(dvb_device_t *) file->private_data;
        dvb_ca *ca=(dvb_ca*) dvbdev->priv;
        int i;

        int err=dvb_generic_open(inode, file);
        if (err<0)
                return err;

        ca->open = 1;
        return 0;
}


/**
 * Implementation of file close syscall.
 *
 * @param inode Inode concerned.
 * @param file File concerned.
 *
 * @return 0 on success, <0 on failure.
 */
int dvb_ca_io_release(struct inode *inode, struct file *file) {
        dvb_device_t *dvbdev=(dvb_device_t *) file->private_data;
        dvb_ca *ca=(dvb_ca*) dvbdev->priv;
        int i;

        /* mark the CA device as closed */
        ca->open = 0;

        /* flush connection buffers */
        for(i=0; i< ca->slot_count; i++) {
                dvb_ca_buf_flush_buffers(ca, slot);
        }

        int err=dvb_generic_release(inode, file);
        if (err<0)
                return err;
        return 0;
}


/**
 * Implementation of poll() syscall.
 *
 * @param file File concerned.
 * @param wait poll wait table.
 *
 * @return Standard poll mask.
 */
unsigned int dvb_ca_io_poll(struct file *file, poll_table *wait) {
        dvb_device_t* dvbdev = (dvb_device_t*) file->private_data;
        dvb_ca* ca = (dvb_ca*) dvbdev->priv;
        unsigned int mask=0;
        int slot;
        struct dvb_ca_connection* cacon;


        /* go through each slot looking to see if there is data available */
        for(slot=0; slot < ca->slot_count; slot++) {

                /* acquire the slot */
                dvb_ca_slot_acquire(ca, slot);

                /* go through each connection id to see if there is data available */
                list_for_each_entry(cacon, &ca->slot_info[slot].connections, next) {

                        /* if the RX queue is NOT empty... */
                        if (dvb_ringbuffer_avail(&cacon->rx_buffer) > 3) {
                                /* and if the first packet on the RX buffer is marked as complete, data is ready to be read */
                                if (DVB_RINGBUFFER_PEEK(&cacon->rx_buffer, 2) == 1)
                                        mask|= POLLIN;
                        }

                        /* is there data still to be written? */
                        if (!dvb_ringbuffer_empty(&cacon->tx_buffer))
                                mask|=POLLOUT;
                }

                /* finished with this slot now */
                dvb_ca_slot_release(ca, slot);
        }

        /* if there is something, return now */
        if (mask) return mask;

        /* wait for something to happen */
        poll_wait(file, &ca->read_queue, wait);

        /* see if there is some data available now */
        for(slot=0; slot < ca->slot_count; slot++) {

                /* acquire the slot */
                dvb_ca_slot_acquire(ca, slot);

                /* go through each connection id to see if there is data available */
                list_for_each_entry(cacon, &ca->slot_info[slot].connections, next) {

                        /* if the RX queue is NOT empty... */
                        if (dvb_ringbuffer_avail(&cacon->rx_buffer) > 3) {
                                /* and if the first packet on the RX buffer is marked as complete, data is ready to be read */
                                if (DVB_RINGBUFFER_PEEK(&cacon->rx_buffer, 2) == 1)
                                        mask|= POLLIN;
                        }

                        /* is there data still to be written? */
                        if (!dvb_ringbuffer_empty(&cacon->tx_buffer))
                                mask|=POLLOUT;
                }

                /* finished with this slot now */
                dvb_ca_slot_release(ca, slot);
        }

        return mask;
}

/**
 * Real ioctl implementation.
 * NOTE: CA_SEND_MSG/CA_GET_MSG ioctls have userspace buffers passed to them.
 *
 * @param inode Inode concerned.
 * @param file File concerned.
 * @param cmd IOCTL command.
 * @param arg Associated argument.
 *
 * @return 0 on success, <0 on error.
 */
int dvb_ca_io_do_ioctl(struct inode *inode, struct file *file, unsigned int cmd, void *parg) {
        dvb_device_t *dvbdev=(dvb_device_t *) file->private_data;
        dvb_ca* ca=(dvb_ca*) dvbdev->priv;
        int err=0;
        int slot, connection_id;
        ca_msg_t msg;
        int msg_buf_offset = &msg.p.en50021.buf - &msg;

        switch (cmd) {
        case CA_RESET:
                // FIXME: update
                err=dvb_ci_ll_reset(&ci->wbuf, file, (int) parg, &ci->info[0]);
                break;

        case CA_GET_CAP:
        {
                if (ca->flags & DVB_CA_FLAG_EN50221) {
                        ca_cap_t *cap = (ca_cap_t*) parg;

                        cap->slot_num=ca->slot_count;
                        cap->slot_type=CA_EN50221;
                        cap->descr_num=0;
                        cap->descr_type=0;
                }
                break;
        }


        case CA_GET_SLOT_INFO:
        {
                if (ca->flags & DVB_CA_FLAG_EN50221) {
                        ca_slot_info_t *info=(ca_slot_info_t *)parg;

                        if (info->num > ca->slot_count)
                                return -EINVAL;

                        info->type = CA_EN50221;
                        info->flags = 0;
                        if (ca->slot_info[info->num].cam_present)
                                  info->flags = CA_CI_MODULE_PRESENT | CA_CI_MODULE_READY;
                }
                break;
        }

        case CA_GET_MSG:
                if (ca->flags & DVB_CA_FLAG_EN50221) {
                        if (copy_from_user(&msg, parg, msg_buf_offset)) return -EFAULT;

                        err = dvb_ca_buf_copy_to_user(ca, file, parg + msg_buf_offset, msg.p.en50221.length, NULL, &slot, &connection_id);
                        if (err >= 0) {
                                msg.index = slot;
                                msg.type = CA_EN50221;
                                msg.p.en50221.connection_id = connection_id;
                                msg.p.en50221.length = err;
                                if (copy_to_user(&msg, parg, msg_buf_offset)) return -EFAULT;
                        }
                }
                break;

        case CA_SEND_MSG:
                if ((ca->flags & DVB_CA_FLAG_EN50221) && (msg->type == CA_EN50221)) {
                        if (copy_from_user(&msg, parg, msg_buf_offset)) return -EFAULT;

                        err = dvb_ca_buf_copy_from_user(ca, file, parg + msg_buf_offset, msg.p.en50221.length, NULL,
                                                        msg.index, msg.p.en50221.connection_id);
                }
                break;

        case CA_GET_DESCR_INFO:
        case CA_SET_DESCR:
        case CA_SET_PID:
                if (ca->flags & DVB_CA_FLAG_EN50221) {
                        err=-EINVAL;
                }
                break;

        default:
                err=-EINVAL;
                break;
        }

        if (ca->ioctl)
                err=ca->ioctl(ca, cmd, parg);
        if (err<0 && err!=-EINVAL)
                return err;
        return 0;
}


/**
 * Wrapper for ioctl implementation.
 *
 * @param inode Inode concerned.
 * @param file File concerned.
 * @param cmd IOCTL command.
 * @param arg Associated argument.
 *
 * @return 0 on success, <0 on error.
 */
int dvb_ca_io_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) {
        /* need to pass userspace buffer to these two */
        if ((cmd == CA_GET_MSG) || (cmd == CA_SEND_MSG)) {
                return dvb_ca_do_ioctl(inode, file, cmd, (void*) arg);
        }

        /* otherwise, just use the easy route */
        return generic_usercopy(inode, file, cmd, arg, dvb_ca_io_do_ioctl);
}


/**
 * Implementation of write() syscall.
 *
 * @param file File structure.
 * @param buf Source buffer.
 * @param count Size of source buffer.
 * @param ppos Position in file (ignored).
 *
 * @return Number of bytes read, or <0 on error.
 */
ssize_t dvb_ca_io_write(struct file *file, const char *buf, size_t count, loff_t *ppos) {
        dvb_device_t *dvbdev=(dvb_device_t *) file->private_data;
        dvb_ca *ca=(dvb_ca*) dvbdev->priv;
        u8 hdr[2];
        u8 slot, connection_id;

        /* Incoming packet has a 2 byte header. hdr[0] = slot_id, hdr[1] = connection_id */
        if (count < 2) return -EINVAL;

        /* extract slot and connection id */
        if (copy_from_user(hdr, buf, 2)) return -EFAULT;
        slot = hdr[0];
        connection_id = hdr[1];

        /* copy the data from the buffer */
        status = dvb_ca_buf_copy_from_user(ca, file, buf+2, count-2, ppos, slot, connection_id);
        if (status < 0) return status;

        /* success */
        return status + 2;
}


/**
 * Implementation of read() syscall.
 *
 * @param file File structure.
 * @param buf Destination buffer.
 * @param count Size of destination buffer.
 * @param ppos Position in file (ignored).
 *
 * @return Number of bytes read, or <0 on error.
 */
ssize_t dvb_ca_io_read(struct file *file, char *buf, size_t count, loff_t *ppos) {
        dvb_device_t *dvbdev=(dvb_device_t *) file->private_data;
        dvb_ca *ca=(dvb_ca*) dvbdev->priv;
        int status;
        u8 hdr[2];
        u8 slot, connection_id;

        /* Outgoing packet has a 2 byte header. hdr[0] = slot_id, hdr[1] = connection_id */
        if (count < 2) return -EINVAL;

        /* copy the data into the buffer */
        status = dvb_ca_buf_copy_to_user(ca, file, buf+2, count-2, ppos, &slot, &connection_id);
        if (status < 0) return status;

        /* set the slot and connection id */
        hdr[0] = slot;
        hdr[1] = connetion_id;
        if (copy_to_user(buf, hdr, 2)) return -EFAULT;

        /* success */
        return status + 2;
}

static struct file_operations dvb_ca_fops = {
        owner: THIS_MODULE,
        read: dvb_ca_io_read,
        write: dvb_ca_io_write,
        ioctl: dvb_ca_io_ioctl,
        open: dvb_ca_io_open,
        release: dvb_ca_io_release,
        poll: dvb_ca_io_poll,
};

static dvb_device_t dvbdev_ca = {
        priv: 0,
        users: 1,
        writers: 1,
        fops: &dvb_ca_fops,
};





/* ******************************************************************************** */
/* Initialisation/shutdown functions */


/**
 * Initialise a new DVB CA device.
 *
 * @param dvb_adapter DVB adapter to attach the new CA device to.
 * @param ca_dev The dvb_device_t to return.
 * @param ca The dvb_ca instance.
 *
 * @return 0 on success, non