drivers/media/firewire/firedtv-ci.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * FireDTV driver (formerly known as FireSAT)
 *
 * Copyright (C) 2004 Andreas Monitzer <andy@monitzer.com>
 * Copyright (C) 2008 Henrik Kurelid <henrik@kurelid.se>
 */

#include <linux/device.h>
#include <linux/dvb/ca.h>
#include <linux/fs.h>
#include <linux/module.h>

#include <media/dvbdev.h>

#include "firedtv.h"

#define EN50221_TAG_APP_INFO_ENQUIRY	0x9f8020
#define EN50221_TAG_CA_INFO_ENQUIRY	0x9f8030
#define EN50221_TAG_CA_PMT		0x9f8032
#define EN50221_TAG_ENTER_MENU		0x9f8022

static int fdtv_ca_ready(struct firedtv_tuner_status *stat)
{
	return stat->ca_initialization_status	== 1 &&
	       stat->ca_error_flag		== 0 &&
	       stat->ca_dvb_flag		== 1 &&
	       stat->ca_module_present_status	== 1;
}

static int fdtv_get_ca_flags(struct firedtv_tuner_status *stat)
{
	int flags = 0;

	if (stat->ca_module_present_status == 1)
		flags |= CA_CI_MODULE_PRESENT;
	if (stat->ca_initialization_status == 1 &&
	    stat->ca_error_flag            == 0 &&
	    stat->ca_dvb_flag              == 1)
		flags |= CA_CI_MODULE_READY;
	return flags;
}

static int fdtv_ca_get_caps(void *arg)
{
	struct ca_caps *cap = arg;

	cap->slot_num = 1;
	cap->slot_type = CA_CI;
	cap->descr_num = 1;
	cap->descr_type = CA_ECD;
	return 0;
}

static int fdtv_ca_get_slot_info(struct firedtv *fdtv, void *arg)
{
	struct firedtv_tuner_status stat;
	struct ca_slot_info *slot = arg;
	int err;

	err = avc_tuner_status(fdtv, &stat);
	if (err)
		return err;

	if (slot->num != 0)
		return -EACCES;

	slot->type = CA_CI;
	slot->flags = fdtv_get_ca_flags(&stat);
	return 0;
}

static int fdtv_ca_app_info(struct firedtv *fdtv, void *arg)
{
	struct ca_msg *reply = arg;

	return avc_ca_app_info(fdtv, reply->msg, &reply->length);
}

static int fdtv_ca_info(struct firedtv *fdtv, void *arg)
{
	struct ca_msg *reply = arg;

	return avc_ca_info(fdtv, reply->msg, &reply->length);
}

static int fdtv_ca_get_mmi(struct firedtv *fdtv, void *arg)
{
	struct ca_msg *reply = arg;

	return avc_ca_get_mmi(fdtv, reply->msg, &reply->length);
}

static int fdtv_ca_get_msg(struct firedtv *fdtv, void *arg)
{
	struct firedtv_tuner_status stat;
	int err;

	switch (fdtv->ca_last_command) {
	case EN50221_TAG_APP_INFO_ENQUIRY:
		err = fdtv_ca_app_info(fdtv, arg);
		break;
	case EN50221_TAG_CA_INFO_ENQUIRY:
		err = fdtv_ca_info(fdtv, arg);
		break;
	default:
		err = avc_tuner_status(fdtv, &stat);
		if (err)
			break;
		if (stat.ca_mmi == 1)
			err = fdtv_ca_get_mmi(fdtv, arg);
		else {
			dev_info(fdtv->device, "unhandled CA message 0x%08x\n",
				 fdtv->ca_last_command);
			err = -EACCES;
		}
	}
	fdtv->ca_last_command = 0;
	return err;
}

static int fdtv_ca_pmt(struct firedtv *fdtv, void *arg)
{
	struct ca_msg *msg = arg;
	int data_pos;
	int data_length;
	int i;

	data_pos = 4;
	if (msg->msg[3] & 0x80) {
		data_length = 0;
		for (i = 0; i < (msg->msg[3] & 0x7f); i++)
			data_length = (data_length << 8) + msg->msg[data_pos++];
	} else {
		data_length = msg->msg[3];
	}
	if (data_length > sizeof(msg->msg) - data_pos)
		return -EINVAL;

	return avc_ca_pmt(fdtv, &msg->msg[data_pos], data_length);
}

static int fdtv_ca_send_msg(struct firedtv *fdtv, void *arg)
{
	struct ca_msg *msg = arg;
	int err;

	/* Do we need a semaphore for this? */
	fdtv->ca_last_command =
		(msg->msg[0] << 16) + (msg->msg[1] << 8) + msg->msg[2];
	switch (fdtv->ca_last_command) {
	case EN50221_TAG_CA_PMT:
		err = fdtv_ca_pmt(fdtv, arg);
		break;
	case EN50221_TAG_APP_INFO_ENQUIRY:
		/* handled in ca_get_msg */
		err = 0;
		break;
	case EN50221_TAG_CA_INFO_ENQUIRY:
		/* handled in ca_get_msg */
		err = 0;
		break;
	case EN50221_TAG_ENTER_MENU:
		err = avc_ca_enter_menu(fdtv);
		break;
	default:
		dev_err(fdtv->device, "unhandled CA message 0x%08x\n",
			fdtv->ca_last_command);
		err = -EACCES;
	}
	return err;
}

static int fdtv_ca_ioctl(struct file *file, unsigned int cmd, void *arg)
{
	struct dvb_device *dvbdev = file->private_data;
	struct firedtv *fdtv = dvbdev->priv;
	struct firedtv_tuner_status stat;
	int err;

	switch (cmd) {
	case CA_RESET:
		err = avc_ca_reset(fdtv);
		break;
	case CA_GET_CAP:
		err = fdtv_ca_get_caps(arg);
		break;
	case CA_GET_SLOT_INFO:
		err = fdtv_ca_get_slot_info(fdtv, arg);
		break;
	case CA_GET_MSG:
		err = fdtv_ca_get_msg(fdtv, arg);
		break;
	case CA_SEND_MSG:
		err = fdtv_ca_send_msg(fdtv, arg);
		break;
	default:
		dev_info(fdtv->device, "unhandled CA ioctl %u\n", cmd);
		err = -EOPNOTSUPP;
	}

	/* FIXME Is this necessary? */
	avc_tuner_status(fdtv, &stat);

	return err;
}

static __poll_t fdtv_ca_io_poll(struct file *file, poll_table *wait)
{
	return EPOLLIN;
}

static const struct file_operations fdtv_ca_fops = {
	.owner		= THIS_MODULE,
	.unlocked_ioctl	= dvb_generic_ioctl,
	.open		= dvb_generic_open,
	.release	= dvb_generic_release,
	.poll		= fdtv_ca_io_poll,
	.llseek		= noop_llseek,
};

static const struct dvb_device fdtv_ca = {
	.users		= 1,
	.readers	= 1,
	.writers	= 1,
	.fops		= &fdtv_ca_fops,
	.kernel_ioctl	= fdtv_ca_ioctl,
};

int fdtv_ca_register(struct firedtv *fdtv)
{
	struct firedtv_tuner_status stat;
	int err;

	if (avc_tuner_status(fdtv, &stat))
		return -EINVAL;

	if (!fdtv_ca_ready(&stat))
		return -EFAULT;

	err = dvb_register_device(&fdtv->adapter, &fdtv->cadev,
				  &fdtv_ca, fdtv, DVB_DEVICE_CA, 0);

	if (stat.ca_application_info == 0)
		dev_err(fdtv->device, "CaApplicationInfo is not set\n");
	if (stat.ca_date_time_request == 1)
		avc_ca_get_time_date(fdtv, &fdtv->ca_time_interval);

	return err;
}

void fdtv_ca_release(struct firedtv *fdtv)
{
	dvb_unregister_device(fdtv->cadev);
}