[PATCH] dvb: LGDT3302 QAM lock bug fix

[linux-2.6/cjktty.git] / drivers / media / dvb / frontends / lgdt3302.c

/*
 *    Support for LGDT3302 (DViCO FustionHDTV 3 Gold) - VSB/QAM
 *
 *    Copyright (C) 2005 Wilson Michaels <wilsonmichaels@earthlink.net>
 *
 *    Based on code from  Kirk Lapray <kirk_lapray@bigfoot.com>
 *                           Copyright (C) 2005
 *
 *    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.
 *
 */

/*
 *                      NOTES ABOUT THIS DRIVER
 *
 * This driver supports DViCO FusionHDTV 3 Gold under Linux.
 *
 * TODO:
 * BER and signal strength always return 0.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <asm/byteorder.h>

#include "dvb_frontend.h"
#include "dvb-pll.h"
#include "lgdt3302_priv.h"
#include "lgdt3302.h"

static int debug = 0;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug,"Turn on/off lgdt3302 frontend debugging (default:off).");
#define dprintk(args...) \
do { \
if (debug) printk(KERN_DEBUG "lgdt3302: " args); \
} while (0)

struct lgdt3302_state
{
        struct i2c_adapter* i2c;
        struct dvb_frontend_ops ops;

        /* Configuration settings */
        const struct lgdt3302_config* config;

        struct dvb_frontend frontend;

        /* Demodulator private data */
        fe_modulation_t current_modulation;

        /* Tuner private data */
        u32 current_frequency;
};

static int i2c_writebytes (struct lgdt3302_state* state,
                           u8 addr, /* demod_address or pll_address */
                           u8 *buf, /* data bytes to send */
                           int len  /* number of bytes to send */ )
{
        if (addr == state->config->pll_address) {
                struct i2c_msg msg =
                        { .addr = addr, .flags = 0, .buf = buf,  .len = len };
                int err;

                if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
                        printk(KERN_WARNING "lgdt3302: %s error (addr %02x <- %02x, err == %i)\n", __FUNCTION__, addr, buf[0], err);
                        if (err < 0)
                                return err;
                        else
                                return -EREMOTEIO;
                }
        } else {
                u8 tmp[] = { buf[0], buf[1] };
                struct i2c_msg msg =
                        { .addr = addr, .flags = 0, .buf = tmp,  .len = 2 };
                int err;
                int i;

                for (i=1; i<len; i++) {
                        tmp[1] = buf[i];
                        if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
                                printk(KERN_WARNING "lgdt3302: %s error (addr %02x <- %02x, err == %i)\n", __FUNCTION__, addr, buf[0], err);
                                if (err < 0)
                                        return err;
                                else
                                        return -EREMOTEIO;
                        }
                        tmp[0]++;
                }
        }
        return 0;
}
static int i2c_readbytes (struct lgdt3302_state* state,
                          u8 addr, /* demod_address or pll_address */
                          u8 *buf, /* holds data bytes read */
                          int len  /* number of bytes to read */ )
{
        struct i2c_msg msg =
                { .addr = addr, .flags = I2C_M_RD, .buf = buf,  .len = len };
        int err;

        if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
                printk(KERN_WARNING "lgdt3302: %s error (addr %02x, err == %i)\n", __FUNCTION__, addr, err);
                return -EREMOTEIO;
        }
        return 0;
}

/*
 * This routine writes the register (reg) to the demod bus
 * then reads the data returned for (len) bytes.
 */

static u8 i2c_selectreadbytes (struct lgdt3302_state* state,
                               enum I2C_REG reg, u8* buf, int len)
{
        u8 wr [] = { reg };
        struct i2c_msg msg [] = {
                { .addr = state->config->demod_address,
                  .flags = 0, .buf = wr,  .len = 1 },
                { .addr = state->config->demod_address,
                  .flags = I2C_M_RD, .buf = buf, .len = len },
        };
        int ret;
        ret = i2c_transfer(state->i2c, msg, 2);
        if (ret != 2) {
                printk(KERN_WARNING "lgdt3302: %s: addr 0x%02x select 0x%02x error (ret == %i)\n", __FUNCTION__, state->config->demod_address, reg, ret);
        } else {
                ret = 0;
        }
        return ret;
}

/* Software reset */
int lgdt3302_SwReset(struct lgdt3302_state* state)
{
        u8 ret;
        u8 reset[] = {
                IRQ_MASK,
                0x00 /* bit 6 is active low software reset
                      * bits 5-0 are 1 to mask interrupts */
        };

        ret = i2c_writebytes(state,
                             state->config->demod_address,
                             reset, sizeof(reset));
        if (ret == 0) {
                /* spec says reset takes 100 ns why wait */
                /* mdelay(100);    */ /* keep low for 100mS */
                reset[1] = 0x7f;      /* force reset high (inactive)
                                       * and unmask interrupts */
                ret = i2c_writebytes(state,
                                     state->config->demod_address,
                                     reset, sizeof(reset));
        }
        /* Spec does not indicate a need for this either */
        /*mdelay(5); */               /* wait 5 msec before doing more */
        return ret;
}

static int lgdt3302_init(struct dvb_frontend* fe)
{
        /* Hardware reset is done using gpio[0] of cx23880x chip.
         * I'd like to do it here, but don't know how to find chip address.
         * cx88-cards.c arranges for the reset bit to be inactive (high).
         * Maybe there needs to be a callable function in cx88-core or
         * the caller of this function needs to do it. */

        dprintk("%s entered\n", __FUNCTION__);
        return lgdt3302_SwReset((struct lgdt3302_state*) fe->demodulator_priv);
}

static int lgdt3302_read_ber(struct dvb_frontend* fe, u32* ber)
{
        *ber = 0; /* Dummy out for now */
        return 0;
}

static int lgdt3302_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
{
        struct lgdt3302_state* state = (struct lgdt3302_state*) fe->demodulator_priv;
        u8 buf[2];

        i2c_selectreadbytes(state, PACKET_ERR_COUNTER1, buf, sizeof(buf));

        *ucblocks = (buf[0] << 8) | buf[1];
        return 0;
}

static int lgdt3302_set_parameters(struct dvb_frontend* fe,
                                   struct dvb_frontend_parameters *param)
{
        u8 buf[4];
        struct lgdt3302_state* state =
                (struct lgdt3302_state*) fe->demodulator_priv;

        /* Use 50MHz parameter values from spec sheet since xtal is 50 */
        static u8 top_ctrl_cfg[]   = { TOP_CONTROL, 0x03 };
        static u8 vsb_freq_cfg[]   = { VSB_CARRIER_FREQ0, 0x00, 0x87, 0x8e, 0x01 };
        static u8 demux_ctrl_cfg[] = { DEMUX_CONTROL, 0xfb };
        static u8 agc_rf_cfg[]     = { AGC_RF_BANDWIDTH0, 0x40, 0x93, 0x00 };
        static u8 agc_ctrl_cfg[]   = { AGC_FUNC_CTRL2, 0xc6, 0x40 };
        static u8 agc_delay_cfg[]  = { AGC_DELAY0, 0x07, 0x00, 0xfe };
        static u8 agc_loop_cfg[]   = { AGC_LOOP_BANDWIDTH0, 0x08, 0x9a };

        /* Change only if we are actually changing the modulation */
        if (state->current_modulation != param->u.vsb.modulation) {
                switch(param->u.vsb.modulation) {
                case VSB_8:
                        dprintk("%s: VSB_8 MODE\n", __FUNCTION__);

                        /* Select VSB mode and serial MPEG interface */
                        top_ctrl_cfg[1] = 0x07;
                        break;

                case QAM_64:
                        dprintk("%s: QAM_64 MODE\n", __FUNCTION__);

                        /* Select QAM_64 mode and serial MPEG interface */
                        top_ctrl_cfg[1] = 0x04;
                        break;

                case QAM_256:
                        dprintk("%s: QAM_256 MODE\n", __FUNCTION__);

                        /* Select QAM_256 mode and serial MPEG interface */
                        top_ctrl_cfg[1] = 0x05;
                        break;
                default:
                        printk(KERN_WARNING "lgdt3302: %s: Modulation type(%d) UNSUPPORTED\n", __FUNCTION__, param->u.vsb.modulation);
                        return -1;
                }
                /* Initializations common to all modes */

                /* Select the requested mode */
                i2c_writebytes(state, state->config->demod_address,
                               top_ctrl_cfg, sizeof(top_ctrl_cfg));

                /* Change the value of IFBW[11:0]
                   of AGC IF/RF loop filter bandwidth register */
                i2c_writebytes(state, state->config->demod_address,
                               agc_rf_cfg, sizeof(agc_rf_cfg));

                /* Change the value of bit 6, 'nINAGCBY' and
                   'NSSEL[1:0] of ACG function control register 2 */
                /* Change the value of bit 6 'RFFIX'
                   of AGC function control register 3 */
                i2c_writebytes(state, state->config->demod_address,
                               agc_ctrl_cfg, sizeof(agc_ctrl_cfg));

                /* Change the TPCLK pin polarity
                   data is valid on falling clock */
                i2c_writebytes(state, state->config->demod_address,
                               demux_ctrl_cfg, sizeof(demux_ctrl_cfg));

                /* Change the value of NCOCTFV[25:0] of carrier
                   recovery center frequency register */
                i2c_writebytes(state, state->config->demod_address,
                                       vsb_freq_cfg, sizeof(vsb_freq_cfg));

                /* Set the value of 'INLVTHD' register 0x2a/0x2c to 0x7fe */
                i2c_writebytes(state, state->config->demod_address,
                               agc_delay_cfg, sizeof(agc_delay_cfg));

                /* Change the value of IAGCBW[15:8]
                   of inner AGC loop filter bandwith */
                i2c_writebytes(state, state->config->demod_address,
                               agc_loop_cfg, sizeof(agc_loop_cfg));

                state->config->set_ts_params(fe, 0);
                state->current_modulation = param->u.vsb.modulation;
        }

        /* Change only if we are actually changing the channel */
        if (state->current_frequency != param->frequency) {
                dvb_pll_configure(state->config->pll_desc, buf,
                                  param->frequency, 0);
                dprintk("%s: tuner bytes: 0x%02x 0x%02x "
                        "0x%02x 0x%02x\n", __FUNCTION__, buf[0],buf[1],buf[2],buf[3]);
                i2c_writebytes(state, state->config->pll_address ,buf, 4);

                /* Check the status of the tuner pll */
                i2c_readbytes(state, state->config->pll_address, buf, 1);
                dprintk("%s: tuner status byte = 0x%02x\n", __FUNCTION__, buf[0]);

                /* Update current frequency */
                state->current_frequency = param->frequency;
        }
        lgdt3302_SwReset(state);
        return 0;
}

static int lgdt3302_get_frontend(struct dvb_frontend* fe,
                                 struct dvb_frontend_parameters* param)
{
        struct lgdt3302_state *state = fe->demodulator_priv;
        param->frequency = state->current_frequency;
        return 0;
}

static int lgdt3302_read_status(struct dvb_frontend* fe, fe_status_t* status)
{
        struct lgdt3302_state* state = (struct lgdt3302_state*) fe->demodulator_priv;
        u8 buf[3];

        *status = 0; /* Reset status result */

        /* Check the status of the tuner pll */
        i2c_readbytes(state, state->config->pll_address, buf, 1);
        dprintk("%s: tuner status byte = 0x%02x\n", __FUNCTION__, buf[0]);
        if ((buf[0] & 0xc0) != 0x40)
                return 0; /* Tuner PLL not locked or not powered on */

        /*
         * You must set the Mask bits to 1 in the IRQ_MASK in order
         * to see that status bit in the IRQ_STATUS register.
         * This is done in SwReset();
         */

        /* AGC status register */
        i2c_selectreadbytes(state, AGC_STATUS, buf, 1);
        dprintk("%s: AGC_STATUS = 0x%02x\n", __FUNCTION__, buf[0]);
        if ((buf[0] & 0x0c) == 0x8){
                /* Test signal does not exist flag */
                /* as well as the AGC lock flag.   */
                *status |= FE_HAS_SIGNAL;
        } else {
                /* Without a signal all other status bits are meaningless */
                return 0;
        }

        /* signal status */
        i2c_selectreadbytes(state, TOP_CONTROL, buf, sizeof(buf));
        dprintk("%s: TOP_CONTROL = 0x%02x, IRO_MASK = 0x%02x, IRQ_STATUS = 0x%02x\n", __FUNCTION__, buf[0], buf[1], buf[2]);

#if 0
        /* Alternative method to check for a signal */
        /* using the SNR good/bad interrupts.   */
        if ((buf[2] & 0x30) == 0x10)
                *status |= FE_HAS_SIGNAL;
#endif

        /* sync status */
        if ((buf[2] & 0x03) == 0x01) {
                *status |= FE_HAS_SYNC;
        }

        /* FEC error status */
        if ((buf[2] & 0x0c) == 0x08) {
                *status |= FE_HAS_LOCK;
                *status |= FE_HAS_VITERBI;
        }

        /* Carrier Recovery Lock Status Register */
        i2c_selectreadbytes(state, CARRIER_LOCK, buf, 1);
        dprintk("%s: CARRIER_LOCK = 0x%02x\n", __FUNCTION__, buf[0]);
        switch (state->current_modulation) {
        case QAM_256:
        case QAM_64:
                /* Need to undestand why there are 3 lock levels here */
                if ((buf[0] & 0x07) == 0x07)
                        *status |= FE_HAS_CARRIER;
                break;
        case VSB_8:
                if ((buf[0] & 0x80) == 0x80)
                        *status |= FE_HAS_CARRIER;
                break;
        default:
                printk("KERN_WARNING lgdt3302: %s: Modulation set to unsupported value\n", __FUNCTION__);
        }

        return 0;
}

static int lgdt3302_read_signal_strength(struct dvb_frontend* fe, u16* strength)
{
        /* not directly available. */
        return 0;
}

static int lgdt3302_read_snr(struct dvb_frontend* fe, u16* snr)
{
#ifdef SNR_IN_DB
        /*
         * Spec sheet shows formula for SNR_EQ = 10 log10(25 * 24**2 / noise)
         * and SNR_PH = 10 log10(25 * 32**2 / noise) for equalizer and phase tracker
         * respectively. The following tables are built on these formulas.
         * The usual definition is SNR = 20 log10(signal/noise)
         * If the specification is wrong the value retuned is 1/2 the actual SNR in db.
         *
         * This table is a an ordered list of noise values computed by the
         * formula from the spec sheet such that the index into the table
         * starting at 43 or 45 is the SNR value in db. There are duplicate noise
         * value entries at the beginning because the SNR varies more than
         * 1 db for a change of 1 digit in noise at very small values of noise.
         *
         * Examples from SNR_EQ table:
         * noise SNR
         *   0    43
         *   1    42
         *   2    39
         *   3    37
         *   4    36
         *   5    35
         *   6    34
         *   7    33
         *   8    33
         *   9    32
         *   10   32
         *   11   31
         *   12   31
         *   13   30
         */

        static const u32 SNR_EQ[] =
                { 1,     2,      2,      2, 3,      3,      4,     4,     5,     7,
                  9,     11,     13,     17, 21,     26,     33,    41,    52,    65,
                  81,    102,    129,    162, 204,    257,    323,   406,   511,   644,
                  810,   1020,   1284,   1616, 2035,   2561,   3224,  4059,  5110,  6433,
                  8098,  10195,  12835,  16158, 20341,  25608,  32238, 40585, 51094, 64323,
                  80978, 101945, 128341, 161571, 203406, 256073, 0x40000
                };

        static const u32 SNR_PH[] =
                { 1,     2,      2,      2,      3,      3,     4,     5,     6,     8,
                  10,    12,     15,     19,     23,     29, 37,    46,    58,    73,
                  91,    115,    144,    182,    229,    288, 362,   456,   574,   722,
                  909,   1144,   1440,   1813,   2282,   2873, 3617,  4553,  5732,  7216,
                  9084,  11436,  14396,  18124,  22817,  28724,  36161, 45524, 57312, 72151,
                  90833, 114351, 143960, 181235, 228161, 0x040000
                };

        static u8 buf[5];/* read data buffer */
        static u32 noise;   /* noise value */
        static u32 snr_db;  /* index into SNR_EQ[] */
        struct lgdt3302_state* state = (struct lgdt3302_state*) fe->demodulator_priv;

        /* read both equalizer and pase tracker noise data */
        i2c_selectreadbytes(state, EQPH_ERR0, buf, sizeof(buf));

        if (state->current_modulation == VSB_8) {
                /* Equalizer Mean-Square Error Register for VSB */
                noise = ((buf[0] & 7) << 16) | (buf[1] << 8) | buf[2];

                /*
                 * Look up noise value in table.
                 * A better search algorithm could be used...
                 * watch out there are duplicate entries.
                 */
                for (snr_db = 0; snr_db < sizeof(SNR_EQ); snr_db++) {
                        if (noise < SNR_EQ[snr_db]) {
                                *snr = 43 - snr_db;
                                break;
                        }
                }
        } else {
                /* Phase Tracker Mean-Square Error Register for QAM */
                noise = ((buf[0] & 7<<3) << 13) | (buf[3] << 8) | buf[4];

                /* Look up noise value in table. */
                for (snr_db = 0; snr_db < sizeof(SNR_PH); snr_db++) {
                        if (noise < SNR_PH[snr_db]) {
                                *snr = 45 - snr_db;
                                break;
                        }
                }
        }
#else
        /* Return the raw noise value */
        static u8 buf[5];/* read data buffer */
        static u32 noise;   /* noise value */
        struct lgdt3302_state* state = (struct lgdt3302_state*) fe->demodulator_priv;

        /* read both equalizer and pase tracker noise data */
        i2c_selectreadbytes(state, EQPH_ERR0, buf, sizeof(buf));

        if (state->current_modulation == VSB_8) {
                /* Equalizer Mean-Square Error Register for VSB */
                noise = ((buf[0] & 7) << 16) | (buf[1] << 8) | buf[2];
        } else {
                /* Phase Tracker Mean-Square Error Register for QAM */
                noise = ((buf[0] & 7<<3) << 13) | (buf[3] << 8) | buf[4];
        }

        /* Small values for noise mean signal is better so invert noise */
        /* Noise is 19 bit value so discard 3 LSB*/
        *snr = ~noise>>3;
#endif

        dprintk("%s: noise = 0x%05x, snr = %idb\n",__FUNCTION__, noise, *snr);

        return 0;
}

static int lgdt3302_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fe_tune_settings)
{
        /* I have no idea about this - it may not be needed */
        fe_tune_settings->min_delay_ms = 500;
        fe_tune_settings->step_size = 0;
        fe_tune_settings->max_drift = 0;
        return 0;
}

static void lgdt3302_release(struct dvb_frontend* fe)
{
        struct lgdt3302_state* state = (struct lgdt3302_state*) fe->demodulator_priv;
        kfree(state);
}

static struct dvb_frontend_ops lgdt3302_ops;

struct dvb_frontend* lgdt3302_attach(const struct lgdt3302_config* config,
                                     struct i2c_adapter* i2c)
{
        struct lgdt3302_state* state = NULL;
        u8 buf[1];

        /* Allocate memory for the internal state */
        state = (struct lgdt3302_state*) kmalloc(sizeof(struct lgdt3302_state), GFP_KERNEL);
        if (state == NULL)
                goto error;
        memset(state,0,sizeof(*state));

        /* Setup the state */
        state->config = config;
        state->i2c = i2c;
        memcpy(&state->ops, &lgdt3302_ops, sizeof(struct dvb_frontend_ops));
        /* Verify communication with demod chip */
        if (i2c_selectreadbytes(state, 2, buf, 1))
                goto error;

        state->current_frequency = -1;
        state->current_modulation = -1;

        /* Create dvb_frontend */
        state->frontend.ops = &state->ops;
        state->frontend.demodulator_priv = state;
        return &state->frontend;

error:
        if (state)
                kfree(state);
        dprintk("%s: ERROR\n",__FUNCTION__);
        return NULL;
}

static struct dvb_frontend_ops lgdt3302_ops = {
        .info = {
                .name= "LG Electronics LGDT3302 VSB/QAM Frontend",
                .type = FE_ATSC,
                .frequency_min= 54000000,
                .frequency_max= 858000000,
                .frequency_stepsize= 62500,
                /* Symbol rate is for all VSB modes need to check QAM */
                .symbol_rate_min    = 10762000,
                .symbol_rate_max    = 10762000,
                .caps = FE_CAN_QAM_64 | FE_CAN_QAM_256 | FE_CAN_8VSB
        },
        .init                 = lgdt3302_init,
        .set_frontend         = lgdt3302_set_parameters,
        .get_frontend         = lgdt3302_get_frontend,
        .get_tune_settings    = lgdt3302_get_tune_settings,
        .read_status          = lgdt3302_read_status,
        .read_ber             = lgdt3302_read_ber,
        .read_signal_strength = lgdt3302_read_signal_strength,
        .read_snr             = lgdt3302_read_snr,
        .read_ucblocks        = lgdt3302_read_ucblocks,
        .release              = lgdt3302_release,
};

MODULE_DESCRIPTION("LGDT3302 [DViCO FusionHDTV 3 Gold] (ATSC 8VSB & ITU-T J.83 AnnexB 64/256 QAM) Demodulator Driver");
MODULE_AUTHOR("Wilson Michaels");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(lgdt3302_attach);

/*
 * Local variables:
 * c-basic-offset: 8
 * compile-command: "make DVB=1"
 * End:
 */