/*
 * FireDTV driver (formerly known as FireSAT)
 *
 * Copyright (C) 2004 Andreas Monitzer <andy@monitzer.com>
 * Copyright (C) 2008 Ben Backx <ben@bbackx.com>
 * Copyright (C) 2008 Henrik Kurelid <henrik@kurelid.se>
 *
 *      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/bug.h>
#include <linux/crc32.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/mutex.h>
#include <linux/string.h>
#include <linux/stringify.h>
#include <linux/wait.h>
#include <linux/workqueue.h>

#include "firedtv.h"

#define FCP_COMMAND_REGISTER            0xfffff0000b00ULL

#define AVC_CTYPE_CONTROL               0x0
#define AVC_CTYPE_STATUS                0x1
#define AVC_CTYPE_NOTIFY                0x3

#define AVC_RESPONSE_ACCEPTED           0x9
#define AVC_RESPONSE_STABLE             0xc
#define AVC_RESPONSE_CHANGED            0xd
#define AVC_RESPONSE_INTERIM            0xf

#define AVC_SUBUNIT_TYPE_TUNER          (0x05 << 3)
#define AVC_SUBUNIT_TYPE_UNIT           (0x1f << 3)

#define AVC_OPCODE_VENDOR               0x00
#define AVC_OPCODE_READ_DESCRIPTOR      0x09
#define AVC_OPCODE_DSIT                 0xc8
#define AVC_OPCODE_DSD                  0xcb

#define DESCRIPTOR_TUNER_STATUS         0x80
#define DESCRIPTOR_SUBUNIT_IDENTIFIER   0x00

#define SFE_VENDOR_DE_COMPANYID_0       0x00 /* OUI of Digital Everywhere */
#define SFE_VENDOR_DE_COMPANYID_1       0x12
#define SFE_VENDOR_DE_COMPANYID_2       0x87

#define SFE_VENDOR_OPCODE_REGISTER_REMOTE_CONTROL 0x0a
#define SFE_VENDOR_OPCODE_LNB_CONTROL           0x52
#define SFE_VENDOR_OPCODE_TUNE_QPSK             0x58 /* for DVB-S */

#define SFE_VENDOR_OPCODE_GET_FIRMWARE_VERSION  0x00
#define SFE_VENDOR_OPCODE_HOST2CA               0x56
#define SFE_VENDOR_OPCODE_CA2HOST               0x57
#define SFE_VENDOR_OPCODE_CISTATUS              0x59
#define SFE_VENDOR_OPCODE_TUNE_QPSK2            0x60 /* for DVB-S2 */

#define SFE_VENDOR_TAG_CA_RESET                 0x00
#define SFE_VENDOR_TAG_CA_APPLICATION_INFO      0x01
#define SFE_VENDOR_TAG_CA_PMT                   0x02
#define SFE_VENDOR_TAG_CA_DATE_TIME             0x04
#define SFE_VENDOR_TAG_CA_MMI                   0x05
#define SFE_VENDOR_TAG_CA_ENTER_MENU            0x07

#define EN50221_LIST_MANAGEMENT_ONLY    0x03
#define EN50221_TAG_APP_INFO            0x9f8021
#define EN50221_TAG_CA_INFO             0x9f8031

struct avc_command_frame {
        int length;
        u8 ctype;
        u8 subunit;
        u8 opcode;
        u8 operand[509];
};

struct avc_response_frame {
        int length;
        u8 response;
        u8 subunit;
        u8 opcode;
        u8 operand[509];
};

#define AVC_DEBUG_READ_DESCRIPTOR              0x0001
#define AVC_DEBUG_DSIT                         0x0002
#define AVC_DEBUG_DSD                          0x0004
#define AVC_DEBUG_REGISTER_REMOTE_CONTROL      0x0008
#define AVC_DEBUG_LNB_CONTROL                  0x0010
#define AVC_DEBUG_TUNE_QPSK                    0x0020
#define AVC_DEBUG_TUNE_QPSK2                   0x0040
#define AVC_DEBUG_HOST2CA                      0x0080
#define AVC_DEBUG_CA2HOST                      0x0100
#define AVC_DEBUG_APPLICATION_PMT              0x4000
#define AVC_DEBUG_FCP_PAYLOADS                 0x8000

static int avc_debug;
module_param_named(debug, avc_debug, int, 0644);
MODULE_PARM_DESC(debug, "Verbose logging (none = 0"
        ", FCP subactions"
        ": READ DESCRIPTOR = "          __stringify(AVC_DEBUG_READ_DESCRIPTOR)
        ", DSIT = "                     __stringify(AVC_DEBUG_DSIT)
        ", REGISTER_REMOTE_CONTROL = "  __stringify(AVC_DEBUG_REGISTER_REMOTE_CONTROL)
        ", LNB CONTROL = "              __stringify(AVC_DEBUG_LNB_CONTROL)
        ", TUNE QPSK = "                __stringify(AVC_DEBUG_TUNE_QPSK)
        ", TUNE QPSK2 = "               __stringify(AVC_DEBUG_TUNE_QPSK2)
        ", HOST2CA = "                  __stringify(AVC_DEBUG_HOST2CA)
        ", CA2HOST = "                  __stringify(AVC_DEBUG_CA2HOST)
        "; Application sent PMT = "     __stringify(AVC_DEBUG_APPLICATION_PMT)
        ", FCP payloads = "             __stringify(AVC_DEBUG_FCP_PAYLOADS)
        ", or a combination, or all = -1)");

static const char *debug_fcp_ctype(unsigned int ctype)
{
        static const char *ctypes[] = {
                [0x0] = "CONTROL",              [0x1] = "STATUS",
                [0x2] = "SPECIFIC INQUIRY",     [0x3] = "NOTIFY",
                [0x4] = "GENERAL INQUIRY",      [0x8] = "NOT IMPLEMENTED",
                [0x9] = "ACCEPTED",             [0xa] = "REJECTED",
                [0xb] = "IN TRANSITION",        [0xc] = "IMPLEMENTED/STABLE",
                [0xd] = "CHANGED",              [0xf] = "INTERIM",
        };
        const char *ret = ctype < ARRAY_SIZE(ctypes) ? ctypes[ctype] : NULL;

        return ret ? ret : "?";
}

static const char *debug_fcp_opcode(unsigned int opcode,
                                    const u8 *data, int length)
{
        switch (opcode) {
        case AVC_OPCODE_VENDOR:
                break;
        case AVC_OPCODE_READ_DESCRIPTOR:
                return avc_debug & AVC_DEBUG_READ_DESCRIPTOR ?
                                "ReadDescriptor" : NULL;
        case AVC_OPCODE_DSIT:
                return avc_debug & AVC_DEBUG_DSIT ?
                                "DirectSelectInfo.Type" : NULL;
        case AVC_OPCODE_DSD:
                return avc_debug & AVC_DEBUG_DSD ? "DirectSelectData" : NULL;
        default:
                return "Unknown";
        }

        if (length < 7 ||
            data[3] != SFE_VENDOR_DE_COMPANYID_0 ||
            data[4] != SFE_VENDOR_DE_COMPANYID_1 ||
            data[5] != SFE_VENDOR_DE_COMPANYID_2)
                return "Vendor/Unknown";

        switch (data[6]) {
        case SFE_VENDOR_OPCODE_REGISTER_REMOTE_CONTROL:
                return avc_debug & AVC_DEBUG_REGISTER_REMOTE_CONTROL ?
                                "RegisterRC" : NULL;
        case SFE_VENDOR_OPCODE_LNB_CONTROL:
                return avc_debug & AVC_DEBUG_LNB_CONTROL ? "LNBControl" : NULL;
        case SFE_VENDOR_OPCODE_TUNE_QPSK:
                return avc_debug & AVC_DEBUG_TUNE_QPSK ? "TuneQPSK" : NULL;
        case SFE_VENDOR_OPCODE_TUNE_QPSK2:
                return avc_debug & AVC_DEBUG_TUNE_QPSK2 ? "TuneQPSK2" : NULL;
        case SFE_VENDOR_OPCODE_HOST2CA:
                return avc_debug & AVC_DEBUG_HOST2CA ? "Host2CA" : NULL;
        case SFE_VENDOR_OPCODE_CA2HOST:
                return avc_debug & AVC_DEBUG_CA2HOST ? "CA2Host" : NULL;
        }
        return "Vendor/Unknown";
}

static void debug_fcp(const u8 *data, int length)
{
        unsigned int subunit_type, subunit_id, opcode;
        const char *op, *prefix;

        prefix       = data[0] > 7 ? "FCP <- " : "FCP -> ";
        subunit_type = data[1] >> 3;
        subunit_id   = data[1] & 7;
        opcode       = subunit_type == 0x1e || subunit_id == 5 ? ~0 : data[2];
        op           = debug_fcp_opcode(opcode, data, length);

        if (op) {
                printk(KERN_INFO "%ssu=%x.%x l=%d: %-8s - %s\n",
                       prefix, subunit_type, subunit_id, length,
                       debug_fcp_ctype(data[0]), op);
                if (avc_debug & AVC_DEBUG_FCP_PAYLOADS)
                        print_hex_dump(KERN_INFO, prefix, DUMP_PREFIX_NONE,
                                       16, 1, data, length, false);
        }
}

static void debug_pmt(char *msg, int length)
{
        printk(KERN_INFO "APP PMT -> l=%d\n", length);
        print_hex_dump(KERN_INFO, "APP PMT -> ", DUMP_PREFIX_NONE,
                       16, 1, msg, length, false);
}

static int __avc_write(struct firedtv *fdtv,
                const struct avc_command_frame *c, struct avc_response_frame *r)
{
        int err, retry;

        if (r)
                fdtv->avc_reply_received = false;

        for (retry = 0; retry < 6; retry++) {
                if (unlikely(avc_debug))
                        debug_fcp(&c->ctype, c->length);

                err = fdtv->backend->write(fdtv, FCP_COMMAND_REGISTER,
                                           (void *)&c->ctype, c->length);
                if (err) {
                        fdtv->avc_reply_received = true;
                        dev_err(fdtv->device, "FCP command write failed\n");
                        return err;
                }

                if (!r)
                        return 0;

                /*
                 * AV/C specs say that answers should be sent within 150 ms.
                 * Time out after 200 ms.
                 */
                if (wait_event_timeout(fdtv->avc_wait,
                                       fdtv->avc_reply_received,
                                       msecs_to_jiffies(200)) != 0) {
                        r->length = fdtv->response_length;
                        memcpy(&r->response, fdtv->response, r->length);

                        return 0;
                }
        }
        dev_err(fdtv->device, "FCP response timed out\n");
        return -ETIMEDOUT;
}

static int avc_write(struct firedtv *fdtv,
                const struct avc_command_frame *c, struct avc_response_frame *r)
{
        int ret;

        if (mutex_lock_interruptible(&fdtv->avc_mutex))
                return -EINTR;

        ret = __avc_write(fdtv, c, r);

        mutex_unlock(&fdtv->avc_mutex);
        return ret;
}

int avc_recv(struct firedtv *fdtv, void *data, size_t length)
{
        struct avc_response_frame *r =
                        data - offsetof(struct avc_response_frame, response);

        if (unlikely(avc_debug))
                debug_fcp(data, length);

        if (length >= 8 &&
            r->operand[0] == SFE_VENDOR_DE_COMPANYID_0 &&
            r->operand[1] == SFE_VENDOR_DE_COMPANYID_1 &&
            r->operand[2] == SFE_VENDOR_DE_COMPANYID_2 &&
            r->operand[3] == SFE_VENDOR_OPCODE_REGISTER_REMOTE_CONTROL) {
                if (r->response == AVC_RESPONSE_CHANGED) {
                        fdtv_handle_rc(fdtv,
                            r->operand[4] << 8 | r->operand[5]);
                        schedule_work(&fdtv->remote_ctrl_work);
                } else if (r->response != AVC_RESPONSE_INTERIM) {
                        dev_info(fdtv->device,
                                 "remote control result = %d\n", r->response);
                }
                return 0;
        }

        if (fdtv->avc_reply_received) {
                dev_err(fdtv->device, "out-of-order AVC response, ignored\n");
                return -EIO;
        }

        memcpy(fdtv->response, data, length);
        fdtv->response_length = length;

        fdtv->avc_reply_received = true;
        wake_up(&fdtv->avc_wait);

        return 0;
}

static int add_pid_filter(struct firedtv *fdtv, u8 *operand)
{
        int i, n, pos = 1;

        for (i = 0, n = 0; i < 16; i++) {
                if (test_bit(i, &fdtv->channel_active)) {
                        operand[pos++] = 0x13; /* flowfunction relay */
                        operand[pos++] = 0x80; /* dsd_sel_spec_valid_flags -> PID */
                        operand[pos++] = (fdtv->channel_pid[i] >> 8) & 0x1f;
                        operand[pos++] = fdtv->channel_pid[i] & 0xff;
                        operand[pos++] = 0x00; /* tableID */
                        operand[pos++] = 0x00; /* filter_length */
                        n++;
                }
        }
        operand[0] = n;

        return pos;
}

/*
 * tuning command for setting the relative LNB frequency
 * (not supported by the AVC standard)
 */
static void avc_tuner_tuneqpsk(struct firedtv *fdtv,
                               struct dvb_frontend_parameters *params,
                               struct avc_command_frame *c)
{
        c->opcode = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        if (fdtv->type == FIREDTV_DVB_S2)
                c->operand[3] = SFE_VENDOR_OPCODE_TUNE_QPSK2;
        else
                c->operand[3] = SFE_VENDOR_OPCODE_TUNE_QPSK;

        c->operand[4] = (params->frequency >> 24) & 0xff;
        c->operand[5] = (params->frequency >> 16) & 0xff;
        c->operand[6] = (params->frequency >> 8) & 0xff;
        c->operand[7] = params->frequency & 0xff;

        c->operand[8] = ((params->u.qpsk.symbol_rate / 1000) >> 8) & 0xff;
        c->operand[9] = (params->u.qpsk.symbol_rate / 1000) & 0xff;

        switch (params->u.qpsk.fec_inner) {
        case FEC_1_2:   c->operand[10] = 0x1; break;
        case FEC_2_3:   c->operand[10] = 0x2; break;
        case FEC_3_4:   c->operand[10] = 0x3; break;
        case FEC_5_6:   c->operand[10] = 0x4; break;
        case FEC_7_8:   c->operand[10] = 0x5; break;
        case FEC_4_5:
        case FEC_8_9:
        case FEC_AUTO:
        default:        c->operand[10] = 0x0;
        }

        if (fdtv->voltage == 0xff)
                c->operand[11] = 0xff;
        else if (fdtv->voltage == SEC_VOLTAGE_18) /* polarisation */
                c->operand[11] = 0;
        else
                c->operand[11] = 1;

        if (fdtv->tone == 0xff)
                c->operand[12] = 0xff;
        else if (fdtv->tone == SEC_TONE_ON) /* band */
                c->operand[12] = 1;
        else
                c->operand[12] = 0;

        if (fdtv->type == FIREDTV_DVB_S2) {
                c->operand[13] = 0x1;
                c->operand[14] = 0xff;
                c->operand[15] = 0xff;
                c->length = 20;
        } else {
                c->length = 16;
        }
}

static void avc_tuner_dsd_dvb_c(struct firedtv *fdtv,
                                struct dvb_frontend_parameters *params,
                                struct avc_command_frame *c)
{
        c->opcode = AVC_OPCODE_DSD;

        c->operand[0] = 0;    /* source plug */
        c->operand[1] = 0xd2; /* subfunction replace */
        c->operand[2] = 0x20; /* system id = DVB */
        c->operand[3] = 0x00; /* antenna number */
        c->operand[4] = 0x11; /* system_specific_multiplex selection_length */

        /* multiplex_valid_flags, high byte */
        c->operand[5] =   0 << 7 /* reserved */
                        | 0 << 6 /* Polarisation */
                        | 0 << 5 /* Orbital_Pos */
                        | 1 << 4 /* Frequency */
                        | 1 << 3 /* Symbol_Rate */
                        | 0 << 2 /* FEC_outer */
                        | (params->u.qam.fec_inner  != FEC_AUTO ? 1 << 1 : 0)
                        | (params->u.qam.modulation != QAM_AUTO ? 1 << 0 : 0);

        /* multiplex_valid_flags, low byte */
        c->operand[6] =   0 << 7 /* NetworkID */
                        | 0 << 0 /* reserved */ ;

        c->operand[7]  = 0x00;
        c->operand[8]  = 0x00;
        c->operand[9]  = 0x00;
        c->operand[10] = 0x00;

        c->operand[11] = (((params->frequency / 4000) >> 16) & 0xff) | (2 << 6);
        c->operand[12] = ((params->frequency / 4000) >> 8) & 0xff;
        c->operand[13] = (params->frequency / 4000) & 0xff;
        c->operand[14] = ((params->u.qpsk.symbol_rate / 1000) >> 12) & 0xff;
        c->operand[15] = ((params->u.qpsk.symbol_rate / 1000) >> 4) & 0xff;
        c->operand[16] = ((params->u.qpsk.symbol_rate / 1000) << 4) & 0xf0;
        c->operand[17] = 0x00;

        switch (params->u.qpsk.fec_inner) {
        case FEC_1_2:   c->operand[18] = 0x1; break;
        case FEC_2_3:   c->operand[18] = 0x2; break;
        case FEC_3_4:   c->operand[18] = 0x3; break;
        case FEC_5_6:   c->operand[18] = 0x4; break;
        case FEC_7_8:   c->operand[18] = 0x5; break;
        case FEC_8_9:   c->operand[18] = 0x6; break;
        case FEC_4_5:   c->operand[18] = 0x8; break;
        case FEC_AUTO:
        default:        c->operand[18] = 0x0;
        }

        switch (params->u.qam.modulation) {
        case QAM_16:    c->operand[19] = 0x08; break;
        case QAM_32:    c->operand[19] = 0x10; break;
        case QAM_64:    c->operand[19] = 0x18; break;
        case QAM_128:   c->operand[19] = 0x20; break;
        case QAM_256:   c->operand[19] = 0x28; break;
        case QAM_AUTO:
        default:        c->operand[19] = 0x00;
        }

        c->operand[20] = 0x00;
        c->operand[21] = 0x00;

        /* Add PIDs to filter */
        c->length = ALIGN(22 + add_pid_filter(fdtv, &c->operand[22]) + 3, 4);
}

static void avc_tuner_dsd_dvb_t(struct firedtv *fdtv,
                                struct dvb_frontend_parameters *params,
                                struct avc_command_frame *c)
{
        struct dvb_ofdm_parameters *ofdm = &params->u.ofdm;

        c->opcode = AVC_OPCODE_DSD;

        c->operand[0] = 0;    /* source plug */
        c->operand[1] = 0xd2; /* subfunction replace */
        c->operand[2] = 0x20; /* system id = DVB */
        c->operand[3] = 0x00; /* antenna number */
        c->operand[4] = 0x0c; /* system_specific_multiplex selection_length */

        /* multiplex_valid_flags, high byte */
        c->operand[5] =
              0 << 7 /* reserved */
            | 1 << 6 /* CenterFrequency */
            | (ofdm->bandwidth      != BANDWIDTH_AUTO        ? 1 << 5 : 0)
            | (ofdm->constellation  != QAM_AUTO              ? 1 << 4 : 0)
            | (ofdm->hierarchy_information != HIERARCHY_AUTO ? 1 << 3 : 0)
            | (ofdm->code_rate_HP   != FEC_AUTO              ? 1 << 2 : 0)
            | (ofdm->code_rate_LP   != FEC_AUTO              ? 1 << 1 : 0)
            | (ofdm->guard_interval != GUARD_INTERVAL_AUTO   ? 1 << 0 : 0);

        /* multiplex_valid_flags, low byte */
        c->operand[6] =
              0 << 7 /* NetworkID */
            | (ofdm->transmission_mode != TRANSMISSION_MODE_AUTO ? 1 << 6 : 0)
            | 0 << 5 /* OtherFrequencyFlag */
            | 0 << 0 /* reserved */ ;

        c->operand[7]  = 0x0;
        c->operand[8]  = (params->frequency / 10) >> 24;
        c->operand[9]  = ((params->frequency / 10) >> 16) & 0xff;
        c->operand[10] = ((params->frequency / 10) >>  8) & 0xff;
        c->operand[11] = (params->frequency / 10) & 0xff;

        switch (ofdm->bandwidth) {
        case BANDWIDTH_7_MHZ:   c->operand[12] = 0x20; break;
        case BANDWIDTH_8_MHZ:
        case BANDWIDTH_6_MHZ:   /* not defined by AVC spec */
        case BANDWIDTH_AUTO:
        default:                c->operand[12] = 0x00;
        }

        switch (ofdm->constellation) {
        case QAM_16:    c->operand[13] = 1 << 6; break;
        case QAM_64:    c->operand[13] = 2 << 6; break;
        case QPSK:
        default:        c->operand[13] = 0x00;
        }

        switch (ofdm->hierarchy_information) {
        case HIERARCHY_1:       c->operand[13] |= 1 << 3; break;
        case HIERARCHY_2:       c->operand[13] |= 2 << 3; break;
        case HIERARCHY_4:       c->operand[13] |= 3 << 3; break;
        case HIERARCHY_AUTO:
        case HIERARCHY_NONE:
        default:                break;
        }

        switch (ofdm->code_rate_HP) {
        case FEC_2_3:   c->operand[13] |= 1; break;
        case FEC_3_4:   c->operand[13] |= 2; break;
        case FEC_5_6:   c->operand[13] |= 3; break;
        case FEC_7_8:   c->operand[13] |= 4; break;
        case FEC_1_2:
        default:        break;
        }

        switch (ofdm->code_rate_LP) {
        case FEC_2_3:   c->operand[14] = 1 << 5; break;
        case FEC_3_4:   c->operand[14] = 2 << 5; break;
        case FEC_5_6:   c->operand[14] = 3 << 5; break;
        case FEC_7_8:   c->operand[14] = 4 << 5; break;
        case FEC_1_2:
        default:        c->operand[14] = 0x00; break;
        }

        switch (ofdm->guard_interval) {
        case GUARD_INTERVAL_1_16:       c->operand[14] |= 1 << 3; break;
        case GUARD_INTERVAL_1_8:        c->operand[14] |= 2 << 3; break;
        case GUARD_INTERVAL_1_4:        c->operand[14] |= 3 << 3; break;
        case GUARD_INTERVAL_1_32:
        case GUARD_INTERVAL_AUTO:
        default:                        break;
        }

        switch (ofdm->transmission_mode) {
        case TRANSMISSION_MODE_8K:      c->operand[14] |= 1 << 1; break;
        case TRANSMISSION_MODE_2K:
        case TRANSMISSION_MODE_AUTO:
        default:                        break;
        }

        c->operand[15] = 0x00; /* network_ID[0] */
        c->operand[16] = 0x00; /* network_ID[1] */

        /* Add PIDs to filter */
        c->length = ALIGN(17 + add_pid_filter(fdtv, &c->operand[17]) + 3, 4);
}

int avc_tuner_dsd(struct firedtv *fdtv,
                  struct dvb_frontend_parameters *params)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;

        switch (fdtv->type) {
        case FIREDTV_DVB_S:
        case FIREDTV_DVB_S2: avc_tuner_tuneqpsk(fdtv, params, c); break;
        case FIREDTV_DVB_C: avc_tuner_dsd_dvb_c(fdtv, params, c); break;
        case FIREDTV_DVB_T: avc_tuner_dsd_dvb_t(fdtv, params, c); break;
        default:
                BUG();
        }

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        msleep(500);
#if 0
        /* FIXME: */
        /* u8 *status was an out-parameter of avc_tuner_dsd, unused by caller */
        if (status)
                *status = r->operand[2];
#endif
        return 0;
}

int avc_tuner_set_pids(struct firedtv *fdtv, unsigned char pidc, u16 pid[])
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */
        int pos, k;

        if (pidc > 16 && pidc != 0xff)
                return -EINVAL;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_DSD;

        c->operand[0] = 0;      /* source plug */
        c->operand[1] = 0xd2;   /* subfunction replace */
        c->operand[2] = 0x20;   /* system id = DVB */
        c->operand[3] = 0x00;   /* antenna number */
        c->operand[4] = 0x00;   /* system_specific_multiplex selection_length */
        c->operand[5] = pidc;   /* Nr_of_dsd_sel_specs */

        pos = 6;
        if (pidc != 0xff)
                for (k = 0; k < pidc; k++) {
                        c->operand[pos++] = 0x13; /* flowfunction relay */
                        c->operand[pos++] = 0x80; /* dsd_sel_spec_valid_flags -> PID */
                        c->operand[pos++] = (pid[k] >> 8) & 0x1f;
                        c->operand[pos++] = pid[k] & 0xff;
                        c->operand[pos++] = 0x00; /* tableID */
                        c->operand[pos++] = 0x00; /* filter_length */
                }

        c->length = ALIGN(3 + pos, 4);

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        msleep(50);
        return 0;
}

int avc_tuner_get_ts(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */
        int sl;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_DSIT;

        sl = fdtv->type == FIREDTV_DVB_T ? 0x0c : 0x11;

        c->operand[0] = 0;      /* source plug */
        c->operand[1] = 0xd2;   /* subfunction replace */
        c->operand[2] = 0xff;   /* status */
        c->operand[3] = 0x20;   /* system id = DVB */
        c->operand[4] = 0x00;   /* antenna number */
        c->operand[5] = 0x0;    /* system_specific_search_flags */
        c->operand[6] = sl;     /* system_specific_multiplex selection_length */
        c->operand[7] = 0x00;   /* valid_flags [0] */
        c->operand[8] = 0x00;   /* valid_flags [1] */
        c->operand[7 + sl] = 0x00; /* nr_of_dsit_sel_specs (always 0) */

        c->length = fdtv->type == FIREDTV_DVB_T ? 24 : 28;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        msleep(250);
        return 0;
}

int avc_identify_subunit(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_READ_DESCRIPTOR;

        c->operand[0] = DESCRIPTOR_SUBUNIT_IDENTIFIER;
        c->operand[1] = 0xff;
        c->operand[2] = 0x00;
        c->operand[3] = 0x00; /* length highbyte */
        c->operand[4] = 0x08; /* length lowbyte  */
        c->operand[5] = 0x00; /* offset highbyte */
        c->operand[6] = 0x0d; /* offset lowbyte  */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        if ((r->response != AVC_RESPONSE_STABLE &&
             r->response != AVC_RESPONSE_ACCEPTED) ||
            (r->operand[3] << 8) + r->operand[4] != 8) {
                dev_err(fdtv->device, "cannot read subunit identifier\n");
                return -EINVAL;
        }
        return 0;
}

#define SIZEOF_ANTENNA_INPUT_INFO 22

int avc_tuner_status(struct firedtv *fdtv, struct firedtv_tuner_status *stat)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;
        int length;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_READ_DESCRIPTOR;

        c->operand[0] = DESCRIPTOR_TUNER_STATUS;
        c->operand[1] = 0xff;   /* read_result_status */
        c->operand[2] = 0x00;   /* reserved */
        c->operand[3] = 0;      /* SIZEOF_ANTENNA_INPUT_INFO >> 8; */
        c->operand[4] = 0;      /* SIZEOF_ANTENNA_INPUT_INFO & 0xff; */
        c->operand[5] = 0x00;
        c->operand[6] = 0x00;

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        if (r->response != AVC_RESPONSE_STABLE &&
            r->response != AVC_RESPONSE_ACCEPTED) {
                dev_err(fdtv->device, "cannot read tuner status\n");
                return -EINVAL;
        }

        length = r->operand[9];
        if (r->operand[1] != 0x10 || length != SIZEOF_ANTENNA_INPUT_INFO) {
                dev_err(fdtv->device, "got invalid tuner status\n");
                return -EINVAL;
        }

        stat->active_system             = r->operand[10];
        stat->searching                 = r->operand[11] >> 7 & 1;
        stat->moving                    = r->operand[11] >> 6 & 1;
        stat->no_rf                     = r->operand[11] >> 5 & 1;
        stat->input                     = r->operand[12] >> 7 & 1;
        stat->selected_antenna          = r->operand[12] & 0x7f;
        stat->ber                       = r->operand[13] << 24 |
                                          r->operand[14] << 16 |
                                          r->operand[15] << 8 |
                                          r->operand[16];
        stat->signal_strength           = r->operand[17];
        stat->raster_frequency          = r->operand[18] >> 6 & 2;
        stat->rf_frequency              = (r->operand[18] & 0x3f) << 16 |
                                          r->operand[19] << 8 |
                                          r->operand[20];
        stat->man_dep_info_length       = r->operand[21];
        stat->front_end_error           = r->operand[22] >> 4 & 1;
        stat->antenna_error             = r->operand[22] >> 3 & 1;
        stat->front_end_power_status    = r->operand[22] >> 1 & 1;
        stat->power_supply              = r->operand[22] & 1;
        stat->carrier_noise_ratio       = r->operand[23] << 8 |
                                          r->operand[24];
        stat->power_supply_voltage      = r->operand[27];
        stat->antenna_voltage           = r->operand[28];
        stat->firewire_bus_voltage      = r->operand[29];
        stat->ca_mmi                    = r->operand[30] & 1;
        stat->ca_pmt_reply              = r->operand[31] >> 7 & 1;
        stat->ca_date_time_request      = r->operand[31] >> 6 & 1;
        stat->ca_application_info       = r->operand[31] >> 5 & 1;
        stat->ca_module_present_status  = r->operand[31] >> 4 & 1;
        stat->ca_dvb_flag               = r->operand[31] >> 3 & 1;
        stat->ca_error_flag             = r->operand[31] >> 2 & 1;
        stat->ca_initialization_status  = r->operand[31] >> 1 & 1;

        return 0;
}

int avc_lnb_control(struct firedtv *fdtv, char voltage, char burst,
                    char conttone, char nrdiseq,
                    struct dvb_diseqc_master_cmd *diseqcmd)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;
        int i, j, k;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_LNB_CONTROL;

        c->operand[4] = voltage;
        c->operand[5] = nrdiseq;

        i = 6;

        for (j = 0; j < nrdiseq; j++) {
                c->operand[i++] = diseqcmd[j].msg_len;

                for (k = 0; k < diseqcmd[j].msg_len; k++)
                        c->operand[i++] = diseqcmd[j].msg[k];
        }

        c->operand[i++] = burst;
        c->operand[i++] = conttone;

        c->length = ALIGN(3 + i, 4);

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        if (r->response != AVC_RESPONSE_ACCEPTED) {
                dev_err(fdtv->device, "LNB control failed\n");
                return -EINVAL;
        }

        return 0;
}

int avc_register_remote_control(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_NOTIFY;
        c->subunit = AVC_SUBUNIT_TYPE_UNIT | 7;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_REGISTER_REMOTE_CONTROL;

        c->length = 8;

        return avc_write(fdtv, c, NULL);
}

void avc_remote_ctrl_work(struct work_struct *work)
{
        struct firedtv *fdtv =
                        container_of(work, struct firedtv, remote_ctrl_work);

        /* Should it be rescheduled in failure cases? */
        avc_register_remote_control(fdtv);
}

#if 0 /* FIXME: unused */
int avc_tuner_host2ca(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_HOST2CA;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_APPLICATION_INFO; /* ca tag */
        c->operand[6] = 0; /* more/last */
        c->operand[7] = 0; /* length */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        return 0;
}
#endif

static int get_ca_object_pos(struct avc_response_frame *r)
{
        int length = 1;

        /* Check length of length field */
        if (r->operand[7] & 0x80)
                length = (r->operand[7] & 0x7f) + 1;
        return length + 7;
}

static int get_ca_object_length(struct avc_response_frame *r)
{
#if 0 /* FIXME: unused */
        int size = 0;
        int i;

        if (r->operand[7] & 0x80)
                for (i = 0; i < (r->operand[7] & 0x7f); i++) {
                        size <<= 8;
                        size += r->operand[8 + i];
                }
#endif
        return r->operand[7];
}

int avc_ca_app_info(struct firedtv *fdtv, char *app_info, unsigned int *len)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;
        int pos;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_STATUS;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_CA2HOST;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_APPLICATION_INFO; /* ca tag */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        /* FIXME: check response code and validate response data */

        pos = get_ca_object_pos(r);
        app_info[0] = (EN50221_TAG_APP_INFO >> 16) & 0xff;
        app_info[1] = (EN50221_TAG_APP_INFO >>  8) & 0xff;
        app_info[2] = (EN50221_TAG_APP_INFO >>  0) & 0xff;
        app_info[3] = 6 + r->operand[pos + 4];
        app_info[4] = 0x01;
        memcpy(&app_info[5], &r->operand[pos], 5 + r->operand[pos + 4]);
        *len = app_info[3] + 4;

        return 0;
}

int avc_ca_info(struct firedtv *fdtv, char *app_info, unsigned int *len)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;
        int pos;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_STATUS;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_CA2HOST;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_APPLICATION_INFO; /* ca tag */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        pos = get_ca_object_pos(r);
        app_info[0] = (EN50221_TAG_CA_INFO >> 16) & 0xff;
        app_info[1] = (EN50221_TAG_CA_INFO >>  8) & 0xff;
        app_info[2] = (EN50221_TAG_CA_INFO >>  0) & 0xff;
        app_info[3] = 2;
        app_info[4] = r->operand[pos + 0];
        app_info[5] = r->operand[pos + 1];
        *len = app_info[3] + 4;

        return 0;
}

int avc_ca_reset(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_HOST2CA;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_RESET; /* ca tag */

        c->operand[6] = 0; /* more/last */
        c->operand[7] = 1; /* length */
        c->operand[8] = 0; /* force hardware reset */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        return 0;
}

int avc_ca_pmt(struct firedtv *fdtv, char *msg, int length)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;
        int list_management;
        int program_info_length;
        int pmt_cmd_id;
        int read_pos;
        int write_pos;
        int es_info_length;
        int crc32_csum;

        if (unlikely(avc_debug & AVC_DEBUG_APPLICATION_PMT))
                debug_pmt(msg, length);

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_CONTROL;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        if (msg[0] != EN50221_LIST_MANAGEMENT_ONLY) {
                dev_info(fdtv->device, "forcing list_management to ONLY\n");
                msg[0] = EN50221_LIST_MANAGEMENT_ONLY;
        }
        /* We take the cmd_id from the programme level only! */
        list_management = msg[0];
        program_info_length = ((msg[4] & 0x0f) << 8) + msg[5];
        if (program_info_length > 0)
                program_info_length--; /* Remove pmt_cmd_id */
        pmt_cmd_id = msg[6];

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_HOST2CA;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_PMT; /* ca tag */
        c->operand[6] = 0; /* more/last */
        /* Use three bytes for length field in case length > 127 */
        c->operand[10] = list_management;
        c->operand[11] = 0x01; /* pmt_cmd=OK_descramble */

        /* TS program map table */

        c->operand[12] = 0x02; /* Table id=2 */
        c->operand[13] = 0x80; /* Section syntax + length */
        /* c->operand[14] = XXXprogram_info_length + 12; */
        c->operand[15] = msg[1]; /* Program number */
        c->operand[16] = msg[2];
        c->operand[17] = 0x01; /* Version number=0 + current/next=1 */
        c->operand[18] = 0x00; /* Section number=0 */
        c->operand[19] = 0x00; /* Last section number=0 */
        c->operand[20] = 0x1f; /* PCR_PID=1FFF */
        c->operand[21] = 0xff;
        c->operand[22] = (program_info_length >> 8); /* Program info length */
        c->operand[23] = (program_info_length & 0xff);

        /* CA descriptors at programme level */
        read_pos = 6;
        write_pos = 24;
        if (program_info_length > 0) {
                pmt_cmd_id = msg[read_pos++];
                if (pmt_cmd_id != 1 && pmt_cmd_id != 4)
                        dev_err(fdtv->device,
                                "invalid pmt_cmd_id %d\n", pmt_cmd_id);

                memcpy(&c->operand[write_pos], &msg[read_pos],
                       program_info_length);
                read_pos += program_info_length;
                write_pos += program_info_length;
        }
        while (read_pos < length) {
                c->operand[write_pos++] = msg[read_pos++];
                c->operand[write_pos++] = msg[read_pos++];
                c->operand[write_pos++] = msg[read_pos++];
                es_info_length =
                        ((msg[read_pos] & 0x0f) << 8) + msg[read_pos + 1];
                read_pos += 2;
                if (es_info_length > 0)
                        es_info_length--; /* Remove pmt_cmd_id */
                c->operand[write_pos++] = es_info_length >> 8;
                c->operand[write_pos++] = es_info_length & 0xff;
                if (es_info_length > 0) {
                        pmt_cmd_id = msg[read_pos++];
                        if (pmt_cmd_id != 1 && pmt_cmd_id != 4)
                                dev_err(fdtv->device, "invalid pmt_cmd_id %d "
                                        "at stream level\n", pmt_cmd_id);

                        memcpy(&c->operand[write_pos], &msg[read_pos],
                               es_info_length);
                        read_pos += es_info_length;
                        write_pos += es_info_length;
                }
        }

        /* CRC */
        c->operand[write_pos++] = 0x00;
        c->operand[write_pos++] = 0x00;
        c->operand[write_pos++] = 0x00;
        c->operand[write_pos++] = 0x00;

        c->operand[7] = 0x82;
        c->operand[8] = (write_pos - 10) >> 8;
        c->operand[9] = (write_pos - 10) & 0xff;
        c->operand[14] = write_pos - 15;

        crc32_csum = crc32_be(0, &c->operand[10], c->operand[12] - 1);
        c->operand[write_pos - 4] = (crc32_csum >> 24) & 0xff;
        c->operand[write_pos - 3] = (crc32_csum >> 16) & 0xff;
        c->operand[write_pos - 2] = (crc32_csum >>  8) & 0xff;
        c->operand[write_pos - 1] = (crc32_csum >>  0) & 0xff;

        c->length = ALIGN(3 + write_pos, 4);

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        if (r->response != AVC_RESPONSE_ACCEPTED) {
                dev_err(fdtv->device,
                        "CA PMT failed with response 0x%x\n", r->response);
                return -EFAULT;
        }

        return 0;
}

int avc_ca_get_time_date(struct firedtv *fdtv, int *interval)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_STATUS;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_CA2HOST;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_DATE_TIME; /* ca tag */
        c->operand[6] = 0; /* more/last */
        c->operand[7] = 0; /* length */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        /* FIXME: check response code and validate response data */

        *interval = r->operand[get_ca_object_pos(r)];

        return 0;
}

int avc_ca_enter_menu(struct firedtv *fdtv)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer; /* FIXME: unused */

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_STATUS;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_HOST2CA;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_ENTER_MENU;
        c->operand[6] = 0; /* more/last */
        c->operand[7] = 0; /* length */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        return 0;
}

int avc_ca_get_mmi(struct firedtv *fdtv, char *mmi_object, unsigned int *len)
{
        char buffer[sizeof(struct avc_command_frame)];
        struct avc_command_frame *c = (void *)buffer;
        struct avc_response_frame *r = (void *)buffer;

        memset(c, 0, sizeof(*c));

        c->ctype   = AVC_CTYPE_STATUS;
        c->subunit = AVC_SUBUNIT_TYPE_TUNER | fdtv->subunit;
        c->opcode  = AVC_OPCODE_VENDOR;

        c->operand[0] = SFE_VENDOR_DE_COMPANYID_0;
        c->operand[1] = SFE_VENDOR_DE_COMPANYID_1;
        c->operand[2] = SFE_VENDOR_DE_COMPANYID_2;
        c->operand[3] = SFE_VENDOR_OPCODE_CA2HOST;
        c->operand[4] = 0; /* slot */
        c->operand[5] = SFE_VENDOR_TAG_CA_MMI;
        c->operand[6] = 0; /* more/last */
        c->operand[7] = 0; /* length */

        c->length = 12;

        if (avc_write(fdtv, c, r) < 0)
                return -EIO;

        /* FIXME: check response code and validate response data */

        *len = get_ca_object_length(r);
        memcpy(mmi_object, &r->operand[get_ca_object_pos(r)], *len);

        return 0;
}

#define CMP_OUTPUT_PLUG_CONTROL_REG_0   0xfffff0000904ULL

static int cmp_read(struct firedtv *fdtv, void *buf, u64 addr, size_t len)
{
        int ret;

        if (mutex_lock_interruptible(&fdtv->avc_mutex))
                return -EINTR;

        ret = fdtv->backend->read(fdtv, addr, buf, len);
        if (ret < 0)
                dev_err(fdtv->device, "CMP: read I/O error\n");

        mutex_unlock(&fdtv->avc_mutex);
        return ret;
}

static int cmp_lock(struct firedtv *fdtv, void *data, u64 addr, __be32 arg)
{
        int ret;

        if (mutex_lock_interruptible(&fdtv->avc_mutex))
                return -EINTR;

        ret = fdtv->backend->lock(fdtv, addr, data, arg);
        if (ret < 0)
                dev_err(fdtv->device, "CMP: lock I/O error\n");

        mutex_unlock(&fdtv->avc_mutex);
        return ret;
}

static inline u32 get_opcr(__be32 opcr, u32 mask, u32 shift)
{
        return (be32_to_cpu(opcr) >> shift) & mask;
}

static inline void set_opcr(__be32 *opcr, u32 value, u32 mask, u32 shift)
{
        *opcr &= ~cpu_to_be32(mask << shift);
        *opcr |= cpu_to_be32((value & mask) << shift);
}

#define get_opcr_online(v)              get_opcr((v), 0x1, 31)
#define get_opcr_p2p_connections(v)     get_opcr((v), 0x3f, 24)
#define get_opcr_channel(v)             get_opcr((v), 0x3f, 16)

#define set_opcr_p2p_connections(p, v)  set_opcr((p), (v), 0x3f, 24)
#define set_opcr_channel(p, v)          set_opcr((p), (v), 0x3f, 16)
#define set_opcr_data_rate(p, v)        set_opcr((p), (v), 0x3, 14)
#define set_opcr_overhead_id(p, v)      set_opcr((p), (v), 0xf, 10)

int cmp_establish_pp_connection(struct firedtv *fdtv, int plug, int channel)
{
        __be32 old_opcr, opcr;
        u64 opcr_address = CMP_OUTPUT_PLUG_CONTROL_REG_0 + (plug << 2);
        int attempts = 0;
        int ret;

        ret = cmp_read(fdtv, &opcr, opcr_address, 4);
        if (ret < 0)
                return ret;

repeat:
        if (!get_opcr_online(opcr)) {
                dev_err(fdtv->device, "CMP: output offline\n");
                return -EBUSY;
        }

        old_opcr = opcr;

        if (get_opcr_p2p_connections(opcr)) {
                if (get_opcr_channel(opcr) != channel) {
                        dev_err(fdtv->device, "CMP: cannot change channel\n");
                        return -EBUSY;
                }
                dev_info(fdtv->device, "CMP: overlaying connection\n");

                /* We don't allocate isochronous resources. */
        } else {
                set_opcr_channel(&opcr, channel);
                set_opcr_data_rate(&opcr, 2); /* S400 */

                /* FIXME: this is for the worst case - optimize */
                set_opcr_overhead_id(&opcr, 0);

                /*
                 * FIXME: allocate isochronous channel and bandwidth at IRM
                 * fdtv->backend->alloc_resources(fdtv, channels_mask, bw);
                 */
        }

        set_opcr_p2p_connections(&opcr, get_opcr_p2p_connections(opcr) + 1);

        ret = cmp_lock(fdtv, &opcr, opcr_address, old_opcr);
        if (ret < 0)
                return ret;

        if (old_opcr != opcr) {
                /*
                 * FIXME: if old_opcr.P2P_Connections > 0,
                 * deallocate isochronous channel and bandwidth at IRM
                 * if (...)
                 *      fdtv->backend->dealloc_resources(fdtv, channel, bw);
                 */

                if (++attempts < 6) /* arbitrary limit */
                        goto repeat;
                return -EBUSY;
        }

        return 0;
}

void cmp_break_pp_connection(struct firedtv *fdtv, int plug, int channel)
{
        __be32 old_opcr, opcr;
        u64 opcr_address = CMP_OUTPUT_PLUG_CONTROL_REG_0 + (plug << 2);
        int attempts = 0;

        if (cmp_read(fdtv, &opcr, opcr_address, 4) < 0)
                return;

repeat:
        if (!get_opcr_online(opcr) || !get_opcr_p2p_connections(opcr) ||
            get_opcr_channel(opcr) != channel) {
                dev_err(fdtv->device, "CMP: no connection to break\n");
                return;
        }

        old_opcr = opcr;
        set_opcr_p2p_connections(&opcr, get_opcr_p2p_connections(opcr) - 1);

        if (cmp_lock(fdtv, &opcr, opcr_address, old_opcr) < 0)
                return;

        if (old_opcr != opcr) {
                /*
                 * FIXME: if old_opcr.P2P_Connections == 1, i.e. we were last
                 * owner, deallocate isochronous channel and bandwidth at IRM
                 * if (...)
                 *      fdtv->backend->dealloc_resources(fdtv, channel, bw);
                 */

                if (++attempts < 6) /* arbitrary limit */
                        goto repeat;
        }
}