lgs8gxx.c

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/*
 *    Support for Legend Silicon GB20600 (a.k.a DMB-TH) demodulator
 *    LGS8913, LGS8GL5, LGS8G75
 *    experimental support LGS8G42, LGS8G52
 *
 *    Copyright (C) 2007-2009 David T.L. Wong <[email protected]>
 *    Copyright (C) 2008 Sirius International (Hong Kong) Limited
 *    Timothy Lee <[email protected]> (for initial work on LGS8GL5)
 *
 *    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.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <asm/div64.h>
#include <linux/firmware.h>

#include "dvb_frontend.h"

#include "lgs8gxx.h"
#include "lgs8gxx_priv.h"

#define dprintk(args...) \
    do { \
        if (debug) \
            printk(KERN_DEBUG "lgs8gxx: " args); \
    } while (0)

static int debug;
static int fake_signal_str = 1;

#define LGS8GXX_FIRMWARE "lgs8g75.fw"

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

module_param(fake_signal_str, int, 0644);
MODULE_PARM_DESC(fake_signal_str, "fake signal strength for LGS8913."
"Signal strength calculation is slow.(default:on).");

/* LGS8GXX internal helper functions */

static int lgs8gxx_write_reg(struct lgs8gxx_state *priv, u8 reg, u8 data)
{
    int ret;
    u8 buf[] = { reg, data };
    struct i2c_msg msg = { .flags = 0, .buf = buf, .len = 2 };

    msg.addr = priv->config->demod_address;
    if (priv->config->prod != LGS8GXX_PROD_LGS8G75 && reg >= 0xC0)
        msg.addr += 0x02;

    if (debug >= 2)
        dprintk("%s: reg=0x%02X, data=0x%02X\n", __func__, reg, data);

    ret = i2c_transfer(priv->i2c, &msg, 1);

    if (ret != 1)
        dprintk("%s: error reg=0x%x, data=0x%x, ret=%i\n",
            __func__, reg, data, ret);

    return (ret != 1) ? -1 : 0;
}

static int lgs8gxx_read_reg(struct lgs8gxx_state *priv, u8 reg, u8 *p_data)
{
    int ret;
    u8 dev_addr;

    u8 b0[] = { reg };
    u8 b1[] = { 0 };
    struct i2c_msg msg[] = {
        { .flags = 0, .buf = b0, .len = 1 },
        { .flags = I2C_M_RD, .buf = b1, .len = 1 },
    };

    dev_addr = priv->config->demod_address;
    if (priv->config->prod != LGS8GXX_PROD_LGS8G75 && reg >= 0xC0)
        dev_addr += 0x02;
    msg[1].addr =  msg[0].addr = dev_addr;

    ret = i2c_transfer(priv->i2c, msg, 2);
    if (ret != 2) {
        dprintk("%s: error reg=0x%x, ret=%i\n", __func__, reg, ret);
        return -1;
    }

    *p_data = b1[0];
    if (debug >= 2)
        dprintk("%s: reg=0x%02X, data=0x%02X\n", __func__, reg, b1[0]);
    return 0;
}

static int lgs8gxx_soft_reset(struct lgs8gxx_state *priv)
{
    lgs8gxx_write_reg(priv, 0x02, 0x00);
    msleep(1);
    lgs8gxx_write_reg(priv, 0x02, 0x01);
    msleep(100);

    return 0;
}

static int wait_reg_mask(struct lgs8gxx_state *priv, u8 reg, u8 mask,
    u8 val, u8 delay, u8 tries)
{
    u8 t;
    int i;

    for (i = 0; i < tries; i++) {
        lgs8gxx_read_reg(priv, reg, &t);

        if ((t & mask) == val)
            return 0;
        msleep(delay);
    }

    return 1;
}

static int lgs8gxx_set_ad_mode(struct lgs8gxx_state *priv)
{
    const struct lgs8gxx_config *config = priv->config;
    u8 if_conf;

    if_conf = 0x10; /* AGC output on, RF_AGC output off; */

    if_conf |=
        ((config->ext_adc) ? 0x80 : 0x00) |
        ((config->if_neg_center) ? 0x04 : 0x00) |
        ((config->if_freq == 0) ? 0x08 : 0x00) | /* Baseband */
        ((config->adc_signed) ? 0x02 : 0x00) |
        ((config->if_neg_edge) ? 0x01 : 0x00);

    if (config->ext_adc &&
        (config->prod == LGS8GXX_PROD_LGS8G52)) {
        lgs8gxx_write_reg(priv, 0xBA, 0x40);
    }

    lgs8gxx_write_reg(priv, 0x07, if_conf);

    return 0;
}

static int lgs8gxx_set_if_freq(struct lgs8gxx_state *priv, u32 freq /*in kHz*/)
{
    u64 val;
    u32 v32;
    u32 if_clk;

    if_clk = priv->config->if_clk_freq;

    val = freq;
    if (freq != 0) {
        val <<= 32;
        if (if_clk != 0)
            do_div(val, if_clk);
        v32 = val & 0xFFFFFFFF;
        dprintk("Set IF Freq to %dkHz\n", freq);
    } else {
        v32 = 0;
        dprintk("Set IF Freq to baseband\n");
    }
    dprintk("AFC_INIT_FREQ = 0x%08X\n", v32);

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_write_reg(priv, 0x08, 0xFF & (v32));
        lgs8gxx_write_reg(priv, 0x09, 0xFF & (v32 >> 8));
        lgs8gxx_write_reg(priv, 0x0A, 0xFF & (v32 >> 16));
        lgs8gxx_write_reg(priv, 0x0B, 0xFF & (v32 >> 24));
    } else {
        lgs8gxx_write_reg(priv, 0x09, 0xFF & (v32));
        lgs8gxx_write_reg(priv, 0x0A, 0xFF & (v32 >> 8));
        lgs8gxx_write_reg(priv, 0x0B, 0xFF & (v32 >> 16));
        lgs8gxx_write_reg(priv, 0x0C, 0xFF & (v32 >> 24));
    }

    return 0;
}

static int lgs8gxx_get_afc_phase(struct lgs8gxx_state *priv)
{
    u64 val;
    u32 v32 = 0;
    u8 reg_addr, t;
    int i;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
        reg_addr = 0x23;
    else
        reg_addr = 0x48;

    for (i = 0; i < 4; i++) {
        lgs8gxx_read_reg(priv, reg_addr, &t);
        v32 <<= 8;
        v32 |= t;
        reg_addr--;
    }

    val = v32;
    val *= priv->config->if_clk_freq;
    val >>= 32;
    dprintk("AFC = %u kHz\n", (u32)val);
    return 0;
}

static int lgs8gxx_set_mode_auto(struct lgs8gxx_state *priv)
{
    u8 t;
    u8 prod = priv->config->prod;

    if (prod == LGS8GXX_PROD_LGS8913)
        lgs8gxx_write_reg(priv, 0xC6, 0x01);

    if (prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_read_reg(priv, 0x0C, &t);
        t &= (~0x04);
        lgs8gxx_write_reg(priv, 0x0C, t | 0x80);
        lgs8gxx_write_reg(priv, 0x39, 0x00);
        lgs8gxx_write_reg(priv, 0x3D, 0x04);
    } else if (prod == LGS8GXX_PROD_LGS8913 ||
        prod == LGS8GXX_PROD_LGS8GL5 ||
        prod == LGS8GXX_PROD_LGS8G42 ||
        prod == LGS8GXX_PROD_LGS8G52 ||
        prod == LGS8GXX_PROD_LGS8G54) {
        lgs8gxx_read_reg(priv, 0x7E, &t);
        lgs8gxx_write_reg(priv, 0x7E, t | 0x01);

        /* clear FEC self reset */
        lgs8gxx_read_reg(priv, 0xC5, &t);
        lgs8gxx_write_reg(priv, 0xC5, t & 0xE0);
    }

    if (prod == LGS8GXX_PROD_LGS8913) {
        /* FEC auto detect */
        lgs8gxx_write_reg(priv, 0xC1, 0x03);

        lgs8gxx_read_reg(priv, 0x7C, &t);
        t = (t & 0x8C) | 0x03;
        lgs8gxx_write_reg(priv, 0x7C, t);

        /* BER test mode */
        lgs8gxx_read_reg(priv, 0xC3, &t);
        t = (t & 0xEF) |  0x10;
        lgs8gxx_write_reg(priv, 0xC3, t);
    }

    if (priv->config->prod == LGS8GXX_PROD_LGS8G52)
        lgs8gxx_write_reg(priv, 0xD9, 0x40);

    return 0;
}

static int lgs8gxx_set_mode_manual(struct lgs8gxx_state *priv)
{
    u8 t;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        u8 t2;
        lgs8gxx_read_reg(priv, 0x0C, &t);
        t &= (~0x80);
        lgs8gxx_write_reg(priv, 0x0C, t);

        lgs8gxx_read_reg(priv, 0x0C, &t);
        lgs8gxx_read_reg(priv, 0x19, &t2);

        if (((t&0x03) == 0x01) && (t2&0x01)) {
            lgs8gxx_write_reg(priv, 0x6E, 0x05);
            lgs8gxx_write_reg(priv, 0x39, 0x02);
            lgs8gxx_write_reg(priv, 0x39, 0x03);
            lgs8gxx_write_reg(priv, 0x3D, 0x05);
            lgs8gxx_write_reg(priv, 0x3E, 0x28);
            lgs8gxx_write_reg(priv, 0x53, 0x80);
        } else {
            lgs8gxx_write_reg(priv, 0x6E, 0x3F);
            lgs8gxx_write_reg(priv, 0x39, 0x00);
            lgs8gxx_write_reg(priv, 0x3D, 0x04);
        }

        lgs8gxx_soft_reset(priv);
        return 0;
    }

    /* turn off auto-detect; manual settings */
    lgs8gxx_write_reg(priv, 0x7E, 0);
    if (priv->config->prod == LGS8GXX_PROD_LGS8913)
        lgs8gxx_write_reg(priv, 0xC1, 0);

    lgs8gxx_read_reg(priv, 0xC5, &t);
    t = (t & 0xE0) | 0x06;
    lgs8gxx_write_reg(priv, 0xC5, t);

    lgs8gxx_soft_reset(priv);

    return 0;
}

static int lgs8gxx_is_locked(struct lgs8gxx_state *priv, u8 *locked)
{
    int ret = 0;
    u8 t;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
        ret = lgs8gxx_read_reg(priv, 0x13, &t);
    else
        ret = lgs8gxx_read_reg(priv, 0x4B, &t);
    if (ret != 0)
        return ret;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
        *locked = ((t & 0x80) == 0x80) ? 1 : 0;
    else
        *locked = ((t & 0xC0) == 0xC0) ? 1 : 0;
    return 0;
}

/* Wait for Code Acquisition Lock */
static int lgs8gxx_wait_ca_lock(struct lgs8gxx_state *priv, u8 *locked)
{
    int ret = 0;
    u8 reg, mask, val;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        reg = 0x13;
        mask = 0x80;
        val = 0x80;
    } else {
        reg = 0x4B;
        mask = 0xC0;
        val = 0xC0;
    }

    ret = wait_reg_mask(priv, reg, mask, val, 50, 40);
    *locked = (ret == 0) ? 1 : 0;

    return 0;
}

static int lgs8gxx_is_autodetect_finished(struct lgs8gxx_state *priv,
                      u8 *finished)
{
    int ret = 0;
    u8 reg, mask, val;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        reg = 0x1f;
        mask = 0xC0;
        val = 0x80;
    } else {
        reg = 0xA4;
        mask = 0x03;
        val = 0x01;
    }

    ret = wait_reg_mask(priv, reg, mask, val, 10, 20);
    *finished = (ret == 0) ? 1 : 0;

    return 0;
}

static int lgs8gxx_autolock_gi(struct lgs8gxx_state *priv, u8 gi, u8 cpn,
    u8 *locked)
{
    int err = 0;
    u8 ad_fini = 0;
    u8 t1, t2;

    if (gi == GI_945)
        dprintk("try GI 945\n");
    else if (gi == GI_595)
        dprintk("try GI 595\n");
    else if (gi == GI_420)
        dprintk("try GI 420\n");
    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_read_reg(priv, 0x0C, &t1);
        lgs8gxx_read_reg(priv, 0x18, &t2);
        t1 &= ~(GI_MASK);
        t1 |= gi;
        t2 &= 0xFE;
        t2 |= cpn ? 0x01 : 0x00;
        lgs8gxx_write_reg(priv, 0x0C, t1);
        lgs8gxx_write_reg(priv, 0x18, t2);
    } else {
        lgs8gxx_write_reg(priv, 0x04, gi);
    }
    lgs8gxx_soft_reset(priv);
    err = lgs8gxx_wait_ca_lock(priv, locked);
    if (err || !(*locked))
        return err;
    err = lgs8gxx_is_autodetect_finished(priv, &ad_fini);
    if (err != 0)
        return err;
    if (ad_fini) {
        dprintk("auto detect finished\n");
    } else
        *locked = 0;

    return 0;
}

static int lgs8gxx_auto_detect(struct lgs8gxx_state *priv,
                   u8 *detected_param, u8 *gi)
{
    int i, j;
    int err = 0;
    u8 locked = 0, tmp_gi;

    dprintk("%s\n", __func__);

    lgs8gxx_set_mode_auto(priv);
    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_write_reg(priv, 0x67, 0xAA);
        lgs8gxx_write_reg(priv, 0x6E, 0x3F);
    } else {
        /* Guard Interval */
        lgs8gxx_write_reg(priv, 0x03, 00);
    }

    for (i = 0; i < 2; i++) {
        for (j = 0; j < 2; j++) {
            tmp_gi = GI_945;
            err = lgs8gxx_autolock_gi(priv, GI_945, j, &locked);
            if (err)
                goto out;
            if (locked)
                goto locked;
        }
        for (j = 0; j < 2; j++) {
            tmp_gi = GI_420;
            err = lgs8gxx_autolock_gi(priv, GI_420, j, &locked);
            if (err)
                goto out;
            if (locked)
                goto locked;
        }
        tmp_gi = GI_595;
        err = lgs8gxx_autolock_gi(priv, GI_595, 1, &locked);
        if (err)
            goto out;
        if (locked)
            goto locked;
    }

locked:
    if ((err == 0) && (locked == 1)) {
        u8 t;

        if (priv->config->prod != LGS8GXX_PROD_LGS8G75) {
            lgs8gxx_read_reg(priv, 0xA2, &t);
            *detected_param = t;
        } else {
            lgs8gxx_read_reg(priv, 0x1F, &t);
            *detected_param = t & 0x3F;
        }

        if (tmp_gi == GI_945)
            dprintk("GI 945 locked\n");
        else if (tmp_gi == GI_595)
            dprintk("GI 595 locked\n");
        else if (tmp_gi == GI_420)
            dprintk("GI 420 locked\n");
        *gi = tmp_gi;
    }
    if (!locked)
        err = -1;

out:
    return err;
}

static void lgs8gxx_auto_lock(struct lgs8gxx_state *priv)
{
    s8 err;
    u8 gi = 0x2;
    u8 detected_param = 0;

    err = lgs8gxx_auto_detect(priv, &detected_param, &gi);

    if (err != 0) {
        dprintk("lgs8gxx_auto_detect failed\n");
    } else
        dprintk("detected param = 0x%02X\n", detected_param);

    /* Apply detected parameters */
    if (priv->config->prod == LGS8GXX_PROD_LGS8913) {
        u8 inter_leave_len = detected_param & TIM_MASK ;
        /* Fix 8913 time interleaver detection bug */
        inter_leave_len = (inter_leave_len == TIM_MIDDLE) ? 0x60 : 0x40;
        detected_param &= CF_MASK | SC_MASK  | LGS_FEC_MASK;
        detected_param |= inter_leave_len;
    }
    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        u8 t;
        lgs8gxx_read_reg(priv, 0x19, &t);
        t &= 0x81;
        t |= detected_param << 1;
        lgs8gxx_write_reg(priv, 0x19, t);
    } else {
        lgs8gxx_write_reg(priv, 0x7D, detected_param);
        if (priv->config->prod == LGS8GXX_PROD_LGS8913)
            lgs8gxx_write_reg(priv, 0xC0, detected_param);
    }
    /* lgs8gxx_soft_reset(priv); */

    /* Enter manual mode */
    lgs8gxx_set_mode_manual(priv);

    switch (gi) {
    case GI_945:
        priv->curr_gi = 945; break;
    case GI_595:
        priv->curr_gi = 595; break;
    case GI_420:
        priv->curr_gi = 420; break;
    default:
        priv->curr_gi = 945; break;
    }
}

static int lgs8gxx_set_mpeg_mode(struct lgs8gxx_state *priv,
    u8 serial, u8 clk_pol, u8 clk_gated)
{
    int ret = 0;
    u8 t, reg_addr;

    reg_addr = (priv->config->prod == LGS8GXX_PROD_LGS8G75) ? 0x30 : 0xC2;
    ret = lgs8gxx_read_reg(priv, reg_addr, &t);
    if (ret != 0)
        return ret;

    t &= 0xF8;
    t |= serial ? TS_SERIAL : TS_PARALLEL;
    t |= clk_pol ? TS_CLK_INVERTED : TS_CLK_NORMAL;
    t |= clk_gated ? TS_CLK_GATED : TS_CLK_FREERUN;

    ret = lgs8gxx_write_reg(priv, reg_addr, t);
    if (ret != 0)
        return ret;

    return 0;
}

/* A/D input peak-to-peak voltage range */
static int lgs8g75_set_adc_vpp(struct lgs8gxx_state *priv,
    u8 sel)
{
    u8 r26 = 0x73, r27 = 0x90;

    if (priv->config->prod != LGS8GXX_PROD_LGS8G75)
        return 0;

    r26 |= (sel & 0x01) << 7;
    r27 |= (sel & 0x02) >> 1;
    lgs8gxx_write_reg(priv, 0x26, r26);
    lgs8gxx_write_reg(priv, 0x27, r27);

    return 0;
}

/* LGS8913 demod frontend functions */

static int lgs8913_init(struct lgs8gxx_state *priv)
{
    u8 t;

    /* LGS8913 specific */
    lgs8gxx_write_reg(priv, 0xc1, 0x3);

    lgs8gxx_read_reg(priv, 0x7c, &t);
    lgs8gxx_write_reg(priv, 0x7c, (t&0x8c) | 0x3);

    /* LGS8913 specific */
    lgs8gxx_read_reg(priv, 0xc3, &t);
    lgs8gxx_write_reg(priv, 0xc3, t&0x10);


    return 0;
}

static int lgs8g75_init_data(struct lgs8gxx_state *priv)
{
    const struct firmware *fw;
    int rc;
    int i;

    rc = request_firmware(&fw, LGS8GXX_FIRMWARE, &priv->i2c->dev);
    if (rc)
        return rc;

    lgs8gxx_write_reg(priv, 0xC6, 0x40);

    lgs8gxx_write_reg(priv, 0x3D, 0x04);
    lgs8gxx_write_reg(priv, 0x39, 0x00);

    lgs8gxx_write_reg(priv, 0x3A, 0x00);
    lgs8gxx_write_reg(priv, 0x38, 0x00);
    lgs8gxx_write_reg(priv, 0x3B, 0x00);
    lgs8gxx_write_reg(priv, 0x38, 0x00);

    for (i = 0; i < fw->size; i++) {
        lgs8gxx_write_reg(priv, 0x38, 0x00);
        lgs8gxx_write_reg(priv, 0x3A, (u8)(i&0xff));
        lgs8gxx_write_reg(priv, 0x3B, (u8)(i>>8));
        lgs8gxx_write_reg(priv, 0x3C, fw->data[i]);
    }

    lgs8gxx_write_reg(priv, 0x38, 0x00);

    release_firmware(fw);
    return 0;
}

static int lgs8gxx_init(struct dvb_frontend *fe)
{
    struct lgs8gxx_state *priv =
        (struct lgs8gxx_state *)fe->demodulator_priv;
    const struct lgs8gxx_config *config = priv->config;
    u8 data = 0;
    s8 err;
    dprintk("%s\n", __func__);

    lgs8gxx_read_reg(priv, 0, &data);
    dprintk("reg 0 = 0x%02X\n", data);

    if (config->prod == LGS8GXX_PROD_LGS8G75)
        lgs8g75_set_adc_vpp(priv, config->adc_vpp);

    /* Setup MPEG output format */
    err = lgs8gxx_set_mpeg_mode(priv, config->serial_ts,
                    config->ts_clk_pol,
                    config->ts_clk_gated);
    if (err != 0)
        return -EIO;

    if (config->prod == LGS8GXX_PROD_LGS8913)
        lgs8913_init(priv);
    lgs8gxx_set_if_freq(priv, priv->config->if_freq);
    lgs8gxx_set_ad_mode(priv);

    return 0;
}

static void lgs8gxx_release(struct dvb_frontend *fe)
{
    struct lgs8gxx_state *state = fe->demodulator_priv;
    dprintk("%s\n", __func__);

    kfree(state);
}


static int lgs8gxx_write(struct dvb_frontend *fe, const u8 buf[], int len)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;

    if (len != 2)
        return -EINVAL;

    return lgs8gxx_write_reg(priv, buf[0], buf[1]);
}

static int lgs8gxx_set_fe(struct dvb_frontend *fe)
{

    struct lgs8gxx_state *priv = fe->demodulator_priv;

    dprintk("%s\n", __func__);

    /* set frequency */
    if (fe->ops.tuner_ops.set_params) {
        fe->ops.tuner_ops.set_params(fe);
        if (fe->ops.i2c_gate_ctrl)
            fe->ops.i2c_gate_ctrl(fe, 0);
    }

    /* start auto lock */
    lgs8gxx_auto_lock(priv);

    msleep(10);

    return 0;
}

static int lgs8gxx_get_fe(struct dvb_frontend *fe)
{
    struct dtv_frontend_properties *fe_params = &fe->dtv_property_cache;
    dprintk("%s\n", __func__);

    /* TODO: get real readings from device */
    /* inversion status */
    fe_params->inversion = INVERSION_OFF;

    /* bandwidth */
    fe_params->bandwidth_hz = 8000000;

    fe_params->code_rate_HP = FEC_AUTO;
    fe_params->code_rate_LP = FEC_AUTO;

    fe_params->modulation = QAM_AUTO;

    /* transmission mode */
    fe_params->transmission_mode = TRANSMISSION_MODE_AUTO;

    /* guard interval */
    fe_params->guard_interval = GUARD_INTERVAL_AUTO;

    /* hierarchy */
    fe_params->hierarchy = HIERARCHY_NONE;

    return 0;
}

static
int lgs8gxx_get_tune_settings(struct dvb_frontend *fe,
                  struct dvb_frontend_tune_settings *fesettings)
{
    /* FIXME: copy from tda1004x.c */
    fesettings->min_delay_ms = 800;
    fesettings->step_size = 0;
    fesettings->max_drift = 0;
    return 0;
}

static int lgs8gxx_read_status(struct dvb_frontend *fe, fe_status_t *fe_status)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;
    s8 ret;
    u8 t, locked = 0;

    dprintk("%s\n", __func__);
    *fe_status = 0;

    lgs8gxx_get_afc_phase(priv);
    lgs8gxx_is_locked(priv, &locked);
    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        if (locked)
            *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
                FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
        return 0;
    }

    ret = lgs8gxx_read_reg(priv, 0x4B, &t);
    if (ret != 0)
        return -EIO;

    dprintk("Reg 0x4B: 0x%02X\n", t);

    *fe_status = 0;
    if (priv->config->prod == LGS8GXX_PROD_LGS8913) {
        if ((t & 0x40) == 0x40)
            *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER;
        if ((t & 0x80) == 0x80)
            *fe_status |= FE_HAS_VITERBI | FE_HAS_SYNC |
                FE_HAS_LOCK;
    } else {
        if ((t & 0x80) == 0x80)
            *fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
                FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
    }

    /* success */
    dprintk("%s: fe_status=0x%x\n", __func__, *fe_status);
    return 0;
}

static int lgs8gxx_read_signal_agc(struct lgs8gxx_state *priv, u16 *signal)
{
    u16 v;
    u8 agc_lvl[2], cat;

    dprintk("%s()\n", __func__);
    lgs8gxx_read_reg(priv, 0x3F, &agc_lvl[0]);
    lgs8gxx_read_reg(priv, 0x3E, &agc_lvl[1]);

    v = agc_lvl[0];
    v <<= 8;
    v |= agc_lvl[1];

    dprintk("agc_lvl: 0x%04X\n", v);

    if (v < 0x100)
        cat = 0;
    else if (v < 0x190)
        cat = 5;
    else if (v < 0x2A8)
        cat = 4;
    else if (v < 0x381)
        cat = 3;
    else if (v < 0x400)
        cat = 2;
    else if (v == 0x400)
        cat = 1;
    else
        cat = 0;

    *signal = cat * 65535 / 5;

    return 0;
}

static int lgs8913_read_signal_strength(struct lgs8gxx_state *priv, u16 *signal)
{
    u8 t; s8 ret;
    s16 max_strength = 0;
    u8 str;
    u16 i, gi = priv->curr_gi;

    dprintk("%s\n", __func__);

    ret = lgs8gxx_read_reg(priv, 0x4B, &t);
    if (ret != 0)
        return -EIO;

    if (fake_signal_str) {
        if ((t & 0xC0) == 0xC0) {
            dprintk("Fake signal strength\n");
            *signal = 0x7FFF;
        } else
            *signal = 0;
        return 0;
    }

    dprintk("gi = %d\n", gi);
    for (i = 0; i < gi; i++) {

        if ((i & 0xFF) == 0)
            lgs8gxx_write_reg(priv, 0x84, 0x03 & (i >> 8));
        lgs8gxx_write_reg(priv, 0x83, i & 0xFF);

        lgs8gxx_read_reg(priv, 0x94, &str);
        if (max_strength < str)
            max_strength = str;
    }

    *signal = max_strength;
    dprintk("%s: signal=0x%02X\n", __func__, *signal);

    lgs8gxx_read_reg(priv, 0x95, &t);
    dprintk("%s: AVG Noise=0x%02X\n", __func__, t);

    return 0;
}

static int lgs8g75_read_signal_strength(struct lgs8gxx_state *priv, u16 *signal)
{
    u8 t;
    s16 v = 0;

    dprintk("%s\n", __func__);

    lgs8gxx_read_reg(priv, 0xB1, &t);
    v |= t;
    v <<= 8;
    lgs8gxx_read_reg(priv, 0xB0, &t);
    v |= t;

    *signal = v;
    dprintk("%s: signal=0x%02X\n", __func__, *signal);

    return 0;
}

static int lgs8gxx_read_signal_strength(struct dvb_frontend *fe, u16 *signal)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;

    if (priv->config->prod == LGS8GXX_PROD_LGS8913)
        return lgs8913_read_signal_strength(priv, signal);
    else if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
        return lgs8g75_read_signal_strength(priv, signal);
    else
        return lgs8gxx_read_signal_agc(priv, signal);
}

static int lgs8gxx_read_snr(struct dvb_frontend *fe, u16 *snr)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;
    u8 t;
    *snr = 0;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75)
        lgs8gxx_read_reg(priv, 0x34, &t);
    else
        lgs8gxx_read_reg(priv, 0x95, &t);
    dprintk("AVG Noise=0x%02X\n", t);
    *snr = 256 - t;
    *snr <<= 8;
    dprintk("snr=0x%x\n", *snr);

    return 0;
}

static int lgs8gxx_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
{
    *ucblocks = 0;
    dprintk("%s: ucblocks=0x%x\n", __func__, *ucblocks);
    return 0;
}

static void packet_counter_start(struct lgs8gxx_state *priv)
{
    u8 orig, t;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_read_reg(priv, 0x30, &orig);
        orig &= 0xE7;
        t = orig | 0x10;
        lgs8gxx_write_reg(priv, 0x30, t);
        t = orig | 0x18;
        lgs8gxx_write_reg(priv, 0x30, t);
        t = orig | 0x10;
        lgs8gxx_write_reg(priv, 0x30, t);
    } else {
        lgs8gxx_write_reg(priv, 0xC6, 0x01);
        lgs8gxx_write_reg(priv, 0xC6, 0x41);
        lgs8gxx_write_reg(priv, 0xC6, 0x01);
    }
}

static void packet_counter_stop(struct lgs8gxx_state *priv)
{
    u8 t;

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        lgs8gxx_read_reg(priv, 0x30, &t);
        t &= 0xE7;
        lgs8gxx_write_reg(priv, 0x30, t);
    } else {
        lgs8gxx_write_reg(priv, 0xC6, 0x81);
    }
}

static int lgs8gxx_read_ber(struct dvb_frontend *fe, u32 *ber)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;
    u8 reg_err, reg_total, t;
    u32 total_cnt = 0, err_cnt = 0;
    int i;

    dprintk("%s\n", __func__);

    packet_counter_start(priv);
    msleep(200);
    packet_counter_stop(priv);

    if (priv->config->prod == LGS8GXX_PROD_LGS8G75) {
        reg_total = 0x28; reg_err = 0x2C;
    } else {
        reg_total = 0xD0; reg_err = 0xD4;
    }

    for (i = 0; i < 4; i++) {
        total_cnt <<= 8;
        lgs8gxx_read_reg(priv, reg_total+3-i, &t);
        total_cnt |= t;
    }
    for (i = 0; i < 4; i++) {
        err_cnt <<= 8;
        lgs8gxx_read_reg(priv, reg_err+3-i, &t);
        err_cnt |= t;
    }
    dprintk("error=%d total=%d\n", err_cnt, total_cnt);

    if (total_cnt == 0)
        *ber = 0;
    else
        *ber = err_cnt * 100 / total_cnt;

    dprintk("%s: ber=0x%x\n", __func__, *ber);
    return 0;
}

static int lgs8gxx_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
{
    struct lgs8gxx_state *priv = fe->demodulator_priv;

    if (priv->config->tuner_address == 0)
        return 0;
    if (enable) {
        u8 v = 0x80 | priv->config->tuner_address;
        return lgs8gxx_write_reg(priv, 0x01, v);
    }
    return lgs8gxx_write_reg(priv, 0x01, 0);
}

static struct dvb_frontend_ops lgs8gxx_ops = {
    .delsys = { SYS_DTMB },
    .info = {
        .name = "Legend Silicon LGS8913/LGS8GXX DMB-TH",
        .frequency_min = 474000000,
        .frequency_max = 858000000,
        .frequency_stepsize = 10000,
        .caps =
            FE_CAN_FEC_AUTO |
            FE_CAN_QAM_AUTO |
            FE_CAN_TRANSMISSION_MODE_AUTO |
            FE_CAN_GUARD_INTERVAL_AUTO
    },

    .release = lgs8gxx_release,

    .init = lgs8gxx_init,
    .write = lgs8gxx_write,
    .i2c_gate_ctrl = lgs8gxx_i2c_gate_ctrl,

    .set_frontend = lgs8gxx_set_fe,
    .get_frontend = lgs8gxx_get_fe,
    .get_tune_settings = lgs8gxx_get_tune_settings,

    .read_status = lgs8gxx_read_status,
    .read_ber = lgs8gxx_read_ber,
    .read_signal_strength = lgs8gxx_read_signal_strength,
    .read_snr = lgs8gxx_read_snr,
    .read_ucblocks = lgs8gxx_read_ucblocks,
};

struct dvb_frontend *lgs8gxx_attach(const struct lgs8gxx_config *config,
    struct i2c_adapter *i2c)
{
    struct lgs8gxx_state *priv = NULL;
    u8 data = 0;

    dprintk("%s()\n", __func__);

    if (config == NULL || i2c == NULL)
        return NULL;

    priv = kzalloc(sizeof(struct lgs8gxx_state), GFP_KERNEL);
    if (priv == NULL)
        goto error_out;

    priv->config = config;
    priv->i2c = i2c;

    /* check if the demod is there */
    if (lgs8gxx_read_reg(priv, 0, &data) != 0) {
        dprintk("%s lgs8gxx not found at i2c addr 0x%02X\n",
            __func__, priv->config->demod_address);
        goto error_out;
    }

    lgs8gxx_read_reg(priv, 1, &data);

    memcpy(&priv->frontend.ops, &lgs8gxx_ops,
           sizeof(struct dvb_frontend_ops));
    priv->frontend.demodulator_priv = priv;

    if (config->prod == LGS8GXX_PROD_LGS8G75)
        lgs8g75_init_data(priv);

    return &priv->frontend;

error_out:
    dprintk("%s() error_out\n", __func__);
    kfree(priv);
    return NULL;

}
EXPORT_SYMBOL(lgs8gxx_attach);

MODULE_DESCRIPTION("Legend Silicon LGS8913/LGS8GXX DMB-TH demodulator driver");
MODULE_AUTHOR("David T. L. Wong <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_FIRMWARE(LGS8GXX_FIRMWARE);