friio-fe.c

Go to the documentation of this file.

/* DVB USB compliant Linux driver for the Friio USB2.0 ISDB-T receiver.
 *
 * Copyright (C) 2009 Akihiro Tsukada <[email protected]>
 *
 * This module is based off the the gl861 and vp702x modules.
 *
 * 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, version 2.
 *
 * see Documentation/dvb/README.dvb-usb for more information
 */
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>

#include "friio.h"

struct jdvbt90502_state {
    struct i2c_adapter *i2c;
    struct dvb_frontend frontend;
    struct jdvbt90502_config config;
};

/* NOTE: TC90502 has 16bit register-address? */
/* register 0x0100 is used for reading PLL status, so reg is u16 here */
static int jdvbt90502_reg_read(struct jdvbt90502_state *state,
                   const u16 reg, u8 *buf, const size_t count)
{
    int ret;
    u8 wbuf[3];
    struct i2c_msg msg[2];

    wbuf[0] = reg & 0xFF;
    wbuf[1] = 0;
    wbuf[2] = reg >> 8;

    msg[0].addr = state->config.demod_address;
    msg[0].flags = 0;
    msg[0].buf = wbuf;
    msg[0].len = sizeof(wbuf);

    msg[1].addr = msg[0].addr;
    msg[1].flags = I2C_M_RD;
    msg[1].buf = buf;
    msg[1].len = count;

    ret = i2c_transfer(state->i2c, msg, 2);
    if (ret != 2) {
        deb_fe(" reg read failed.\n");
        return -EREMOTEIO;
    }
    return 0;
}

/* currently 16bit register-address is not used, so reg is u8 here */
static int jdvbt90502_single_reg_write(struct jdvbt90502_state *state,
                       const u8 reg, const u8 val)
{
    struct i2c_msg msg;
    u8 wbuf[2];

    wbuf[0] = reg;
    wbuf[1] = val;

    msg.addr = state->config.demod_address;
    msg.flags = 0;
    msg.buf = wbuf;
    msg.len = sizeof(wbuf);

    if (i2c_transfer(state->i2c, &msg, 1) != 1) {
        deb_fe(" reg write failed.");
        return -EREMOTEIO;
    }
    return 0;
}

static int _jdvbt90502_write(struct dvb_frontend *fe, const u8 buf[], int len)
{
    struct jdvbt90502_state *state = fe->demodulator_priv;
    int err, i;
    for (i = 0; i < len - 1; i++) {
        err = jdvbt90502_single_reg_write(state,
                          buf[0] + i, buf[i + 1]);
        if (err)
            return err;
    }

    return 0;
}

/* read pll status byte via the demodulator's I2C register */
/* note: Win box reads it by 8B block at the I2C addr 0x30 from reg:0x80 */
static int jdvbt90502_pll_read(struct jdvbt90502_state *state, u8 *result)
{
    int ret;

    /* +1 for reading */
    u8 pll_addr_byte = (state->config.pll_address << 1) + 1;

    *result = 0;

    ret = jdvbt90502_single_reg_write(state, JDVBT90502_2ND_I2C_REG,
                      pll_addr_byte);
    if (ret)
        goto error;

    ret = jdvbt90502_reg_read(state, 0x0100, result, 1);
    if (ret)
        goto error;

    deb_fe("PLL read val:%02x\n", *result);
    return 0;

error:
    deb_fe("%s:ret == %d\n", __func__, ret);
    return -EREMOTEIO;
}


/* set pll frequency via the demodulator's I2C register */
static int jdvbt90502_pll_set_freq(struct jdvbt90502_state *state, u32 freq)
{
    int ret;
    int retry;
    u8 res1;
    u8 res2[9];

    u8 pll_freq_cmd[PLL_CMD_LEN];
    u8 pll_agc_cmd[PLL_CMD_LEN];
    struct i2c_msg msg[2];
    u32 f;

    deb_fe("%s: freq=%d, step=%d\n", __func__, freq,
           state->frontend.ops.info.frequency_stepsize);
    /* freq -> oscilator frequency conversion. */
    /* freq: 473,000,000 + n*6,000,000 [+ 142857 (center freq. shift)] */
    f = freq / state->frontend.ops.info.frequency_stepsize;
    /* add 399[1/7 MHZ] = 57MHz for the IF  */
    f += 399;
    /* add center frequency shift if necessary */
    if (f % 7 == 0)
        f++;
    pll_freq_cmd[DEMOD_REDIRECT_REG] = JDVBT90502_2ND_I2C_REG; /* 0xFE */
    pll_freq_cmd[ADDRESS_BYTE] = state->config.pll_address << 1;
    pll_freq_cmd[DIVIDER_BYTE1] = (f >> 8) & 0x7F;
    pll_freq_cmd[DIVIDER_BYTE2] = f & 0xFF;
    pll_freq_cmd[CONTROL_BYTE] = 0xB2; /* ref.divider:28, 4MHz/28=1/7MHz */
    pll_freq_cmd[BANDSWITCH_BYTE] = 0x08;   /* UHF band */

    msg[0].addr = state->config.demod_address;
    msg[0].flags = 0;
    msg[0].buf = pll_freq_cmd;
    msg[0].len = sizeof(pll_freq_cmd);

    ret = i2c_transfer(state->i2c, &msg[0], 1);
    if (ret != 1)
        goto error;

    udelay(50);

    pll_agc_cmd[DEMOD_REDIRECT_REG] = pll_freq_cmd[DEMOD_REDIRECT_REG];
    pll_agc_cmd[ADDRESS_BYTE] = pll_freq_cmd[ADDRESS_BYTE];
    pll_agc_cmd[DIVIDER_BYTE1] = pll_freq_cmd[DIVIDER_BYTE1];
    pll_agc_cmd[DIVIDER_BYTE2] = pll_freq_cmd[DIVIDER_BYTE2];
    pll_agc_cmd[CONTROL_BYTE] = 0x9A; /*  AGC_CTRL instead of BANDSWITCH */
    pll_agc_cmd[AGC_CTRL_BYTE] = 0x50;
    /* AGC Time Constant 2s, AGC take-over point:103dBuV(lowest) */

    msg[1].addr = msg[0].addr;
    msg[1].flags = 0;
    msg[1].buf = pll_agc_cmd;
    msg[1].len = sizeof(pll_agc_cmd);

    ret = i2c_transfer(state->i2c, &msg[1], 1);
    if (ret != 1)
        goto error;

    /* I don't know what these cmds are for,  */
    /* but the USB log on a windows box contains them */
    ret = jdvbt90502_single_reg_write(state, 0x01, 0x40);
    ret |= jdvbt90502_single_reg_write(state, 0x01, 0x00);
    if (ret)
        goto error;
    udelay(100);

    /* wait for the demod to be ready? */
#define RETRY_COUNT 5
    for (retry = 0; retry < RETRY_COUNT; retry++) {
        ret = jdvbt90502_reg_read(state, 0x0096, &res1, 1);
        if (ret)
            goto error;
        /* if (res1 != 0x00) goto error; */
        ret = jdvbt90502_reg_read(state, 0x00B0, res2, sizeof(res2));
        if (ret)
            goto error;
        if (res2[0] >= 0xA7)
            break;
        msleep(100);
    }
    if (retry >= RETRY_COUNT) {
        deb_fe("%s: FE does not get ready after freq setting.\n",
               __func__);
        return -EREMOTEIO;
    }

    return 0;
error:
    deb_fe("%s:ret == %d\n", __func__, ret);
    return -EREMOTEIO;
}

static int jdvbt90502_read_status(struct dvb_frontend *fe, fe_status_t *state)
{
    u8 result;
    int ret;

    *state = FE_HAS_SIGNAL;

    ret = jdvbt90502_pll_read(fe->demodulator_priv, &result);
    if (ret) {
        deb_fe("%s:ret == %d\n", __func__, ret);
        return -EREMOTEIO;
    }

    *state = FE_HAS_SIGNAL
        | FE_HAS_CARRIER
        | FE_HAS_VITERBI
        | FE_HAS_SYNC;

    if (result & PLL_STATUS_LOCKED)
        *state |= FE_HAS_LOCK;

    return 0;
}

static int jdvbt90502_read_signal_strength(struct dvb_frontend *fe,
                       u16 *strength)
{
    int ret;
    u8 rbuf[37];

    *strength = 0;

    /* status register (incl. signal strength) : 0x89  */
    /* TODO: read just the necessary registers [0x8B..0x8D]? */
    ret = jdvbt90502_reg_read(fe->demodulator_priv, 0x0089,
                  rbuf, sizeof(rbuf));

    if (ret) {
        deb_fe("%s:ret == %d\n", __func__, ret);
        return -EREMOTEIO;
    }

    /* signal_strength: rbuf[2-4] (24bit BE), use lower 16bit for now. */
    *strength = (rbuf[3] << 8) + rbuf[4];
    if (rbuf[2])
        *strength = 0xffff;

    return 0;
}


/* filter out un-supported properties to notify users */
static int jdvbt90502_set_property(struct dvb_frontend *fe,
                   struct dtv_property *tvp)
{
    int r = 0;

    switch (tvp->cmd) {
    case DTV_DELIVERY_SYSTEM:
        if (tvp->u.data != SYS_ISDBT)
            r = -EINVAL;
        break;
    case DTV_CLEAR:
    case DTV_TUNE:
    case DTV_FREQUENCY:
        break;
    default:
        r = -EINVAL;
    }
    return r;
}

static int jdvbt90502_get_frontend(struct dvb_frontend *fe)
{
    struct dtv_frontend_properties *p = &fe->dtv_property_cache;
    p->inversion = INVERSION_AUTO;
    p->bandwidth_hz = 6000000;
    p->code_rate_HP = FEC_AUTO;
    p->code_rate_LP = FEC_AUTO;
    p->modulation = QAM_64;
    p->transmission_mode = TRANSMISSION_MODE_AUTO;
    p->guard_interval = GUARD_INTERVAL_AUTO;
    p->hierarchy = HIERARCHY_AUTO;
    return 0;
}

static int jdvbt90502_set_frontend(struct dvb_frontend *fe)
{
    struct dtv_frontend_properties *p = &fe->dtv_property_cache;

    struct jdvbt90502_state *state = fe->demodulator_priv;
    int ret;

    deb_fe("%s: Freq:%d\n", __func__, p->frequency);

    /* for recovery from DTV_CLEAN */
    fe->dtv_property_cache.delivery_system = SYS_ISDBT;

    ret = jdvbt90502_pll_set_freq(state, p->frequency);
    if (ret) {
        deb_fe("%s:ret == %d\n", __func__, ret);
        return -EREMOTEIO;
    }

    return 0;
}


static u8 init_code[][2] = {
    {0x01, 0x40},
    {0x04, 0x38},
    {0x05, 0x40},
    {0x07, 0x40},
    {0x0F, 0x4F},
    {0x11, 0x21},
    {0x12, 0x0B},
    {0x13, 0x2F},
    {0x14, 0x31},
    {0x16, 0x02},
    {0x21, 0xC4},
    {0x22, 0x20},
    {0x2C, 0x79},
    {0x2D, 0x34},
    {0x2F, 0x00},
    {0x30, 0x28},
    {0x31, 0x31},
    {0x32, 0xDF},
    {0x38, 0x01},
    {0x39, 0x78},
    {0x3B, 0x33},
    {0x3C, 0x33},
    {0x48, 0x90},
    {0x51, 0x68},
    {0x5E, 0x38},
    {0x71, 0x00},
    {0x72, 0x08},
    {0x77, 0x00},
    {0xC0, 0x21},
    {0xC1, 0x10},
    {0xE4, 0x1A},
    {0xEA, 0x1F},
    {0x77, 0x00},
    {0x71, 0x00},
    {0x71, 0x00},
    {0x76, 0x0C},
};

static const int init_code_len = sizeof(init_code) / sizeof(u8[2]);

static int jdvbt90502_init(struct dvb_frontend *fe)
{
    int i = -1;
    int ret;
    struct i2c_msg msg;

    struct jdvbt90502_state *state = fe->demodulator_priv;

    deb_fe("%s called.\n", __func__);

    msg.addr = state->config.demod_address;
    msg.flags = 0;
    msg.len = 2;
    for (i = 0; i < init_code_len; i++) {
        msg.buf = init_code[i];
        ret = i2c_transfer(state->i2c, &msg, 1);
        if (ret != 1)
            goto error;
    }
    fe->dtv_property_cache.delivery_system = SYS_ISDBT;
    msleep(100);

    return 0;

error:
    deb_fe("%s: init_code[%d] failed. ret==%d\n", __func__, i, ret);
    return -EREMOTEIO;
}


static void jdvbt90502_release(struct dvb_frontend *fe)
{
    struct jdvbt90502_state *state = fe->demodulator_priv;
    kfree(state);
}


static struct dvb_frontend_ops jdvbt90502_ops;

struct dvb_frontend *jdvbt90502_attach(struct dvb_usb_device *d)
{
    struct jdvbt90502_state *state = NULL;

    deb_info("%s called.\n", __func__);

    /* allocate memory for the internal state */
    state = kzalloc(sizeof(struct jdvbt90502_state), GFP_KERNEL);
    if (state == NULL)
        goto error;

    /* setup the state */
    state->i2c = &d->i2c_adap;
    memcpy(&state->config, &friio_fe_config, sizeof(friio_fe_config));

    /* create dvb_frontend */
    memcpy(&state->frontend.ops, &jdvbt90502_ops,
           sizeof(jdvbt90502_ops));
    state->frontend.demodulator_priv = state;

    if (jdvbt90502_init(&state->frontend) < 0)
        goto error;

    return &state->frontend;

error:
    kfree(state);
    return NULL;
}

static struct dvb_frontend_ops jdvbt90502_ops = {
    .delsys = { SYS_ISDBT },
    .info = {
        .name           = "Comtech JDVBT90502 ISDB-T",
        .frequency_min      = 473000000, /* UHF 13ch, center */
        .frequency_max      = 767142857, /* UHF 62ch, center */
        .frequency_stepsize = JDVBT90502_PLL_CLK / JDVBT90502_PLL_DIVIDER,
        .frequency_tolerance    = 0,

        /* NOTE: this driver ignores all parameters but frequency. */
        .caps = FE_CAN_INVERSION_AUTO |
            FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
            FE_CAN_FEC_4_5 | FE_CAN_FEC_5_6 | FE_CAN_FEC_6_7 |
            FE_CAN_FEC_7_8 | FE_CAN_FEC_8_9 | FE_CAN_FEC_AUTO |
            FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
            FE_CAN_TRANSMISSION_MODE_AUTO |
            FE_CAN_GUARD_INTERVAL_AUTO |
            FE_CAN_HIERARCHY_AUTO,
    },

    .release = jdvbt90502_release,

    .init = jdvbt90502_init,
    .write = _jdvbt90502_write,

    .set_property = jdvbt90502_set_property,

    .set_frontend = jdvbt90502_set_frontend,
    .get_frontend = jdvbt90502_get_frontend,

    .read_status = jdvbt90502_read_status,
    .read_signal_strength = jdvbt90502_read_signal_strength,
};