// 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);
}