mc44s803.c

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/*
 *  Driver for Freescale MC44S803 Low Power CMOS Broadband Tuner
 *
 *  Copyright (c) 2009 Jochen Friedrich <[email protected]>
 *
 *  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 <linux/module.h>
#include <linux/delay.h>
#include <linux/dvb/frontend.h>
#include <linux/i2c.h>
#include <linux/slab.h>

#include "dvb_frontend.h"

#include "mc44s803.h"
#include "mc44s803_priv.h"

#define mc_printk(level, format, arg...)    \
    printk(level "mc44s803: " format , ## arg)

/* Writes a single register */
static int mc44s803_writereg(struct mc44s803_priv *priv, u32 val)
{
    u8 buf[3];
    struct i2c_msg msg = {
        .addr = priv->cfg->i2c_address, .flags = 0, .buf = buf, .len = 3
    };

    buf[0] = (val & 0xff0000) >> 16;
    buf[1] = (val & 0xff00) >> 8;
    buf[2] = (val & 0xff);

    if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
        mc_printk(KERN_WARNING, "I2C write failed\n");
        return -EREMOTEIO;
    }
    return 0;
}

/* Reads a single register */
static int mc44s803_readreg(struct mc44s803_priv *priv, u8 reg, u32 *val)
{
    u32 wval;
    u8 buf[3];
    int ret;
    struct i2c_msg msg[] = {
        { .addr = priv->cfg->i2c_address, .flags = I2C_M_RD,
          .buf = buf, .len = 3 },
    };

    wval = MC44S803_REG_SM(MC44S803_REG_DATAREG, MC44S803_ADDR) |
           MC44S803_REG_SM(reg, MC44S803_D);

    ret = mc44s803_writereg(priv, wval);
    if (ret)
        return ret;

    if (i2c_transfer(priv->i2c, msg, 1) != 1) {
        mc_printk(KERN_WARNING, "I2C read failed\n");
        return -EREMOTEIO;
    }

    *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];

    return 0;
}

static int mc44s803_release(struct dvb_frontend *fe)
{
    struct mc44s803_priv *priv = fe->tuner_priv;

    fe->tuner_priv = NULL;
    kfree(priv);

    return 0;
}

static int mc44s803_init(struct dvb_frontend *fe)
{
    struct mc44s803_priv *priv = fe->tuner_priv;
    u32 val;
    int err;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);

/* Reset chip */
    val = MC44S803_REG_SM(MC44S803_REG_RESET, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_RS);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_RESET, MC44S803_ADDR);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

/* Power Up and Start Osc */

    val = MC44S803_REG_SM(MC44S803_REG_REFOSC, MC44S803_ADDR) |
          MC44S803_REG_SM(0xC0, MC44S803_REFOSC) |
          MC44S803_REG_SM(1, MC44S803_OSCSEL);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_POWER, MC44S803_ADDR) |
          MC44S803_REG_SM(0x200, MC44S803_POWER);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    msleep(10);

    val = MC44S803_REG_SM(MC44S803_REG_REFOSC, MC44S803_ADDR) |
          MC44S803_REG_SM(0x40, MC44S803_REFOSC) |
          MC44S803_REG_SM(1, MC44S803_OSCSEL);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    msleep(20);

/* Setup Mixer */

    val = MC44S803_REG_SM(MC44S803_REG_MIXER, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_TRI_STATE) |
          MC44S803_REG_SM(0x7F, MC44S803_MIXER_RES);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

/* Setup Cirquit Adjust */

    val = MC44S803_REG_SM(MC44S803_REG_CIRCADJ, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_G1) |
          MC44S803_REG_SM(1, MC44S803_G3) |
          MC44S803_REG_SM(0x3, MC44S803_CIRCADJ_RES) |
          MC44S803_REG_SM(1, MC44S803_G6) |
          MC44S803_REG_SM(priv->cfg->dig_out, MC44S803_S1) |
          MC44S803_REG_SM(0x3, MC44S803_LP) |
          MC44S803_REG_SM(1, MC44S803_CLRF) |
          MC44S803_REG_SM(1, MC44S803_CLIF);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_CIRCADJ, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_G1) |
          MC44S803_REG_SM(1, MC44S803_G3) |
          MC44S803_REG_SM(0x3, MC44S803_CIRCADJ_RES) |
          MC44S803_REG_SM(1, MC44S803_G6) |
          MC44S803_REG_SM(priv->cfg->dig_out, MC44S803_S1) |
          MC44S803_REG_SM(0x3, MC44S803_LP);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

/* Setup Digtune */

    val = MC44S803_REG_SM(MC44S803_REG_DIGTUNE, MC44S803_ADDR) |
          MC44S803_REG_SM(3, MC44S803_XOD);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

/* Setup AGC */

    val = MC44S803_REG_SM(MC44S803_REG_LNAAGC, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_AT1) |
          MC44S803_REG_SM(1, MC44S803_AT2) |
          MC44S803_REG_SM(1, MC44S803_AGC_AN_DIG) |
          MC44S803_REG_SM(1, MC44S803_AGC_READ_EN) |
          MC44S803_REG_SM(1, MC44S803_LNA0);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);
    return 0;

exit:
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    mc_printk(KERN_WARNING, "I/O Error\n");
    return err;
}

static int mc44s803_set_params(struct dvb_frontend *fe)
{
    struct mc44s803_priv *priv = fe->tuner_priv;
    struct dtv_frontend_properties *c = &fe->dtv_property_cache;
    u32 r1, r2, n1, n2, lo1, lo2, freq, val;
    int err;

    priv->frequency = c->frequency;

    r1 = MC44S803_OSC / 1000000;
    r2 = MC44S803_OSC /  100000;

    n1 = (c->frequency + MC44S803_IF1 + 500000) / 1000000;
    freq = MC44S803_OSC / r1 * n1;
    lo1 = ((60 * n1) + (r1 / 2)) / r1;
    freq = freq - c->frequency;

    n2 = (freq - MC44S803_IF2 + 50000) / 100000;
    lo2 = ((60 * n2) + (r2 / 2)) / r2;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);

    val = MC44S803_REG_SM(MC44S803_REG_REFDIV, MC44S803_ADDR) |
          MC44S803_REG_SM(r1-1, MC44S803_R1) |
          MC44S803_REG_SM(r2-1, MC44S803_R2) |
          MC44S803_REG_SM(1, MC44S803_REFBUF_EN);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_LO1, MC44S803_ADDR) |
          MC44S803_REG_SM(n1-2, MC44S803_LO1);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_LO2, MC44S803_ADDR) |
          MC44S803_REG_SM(n2-2, MC44S803_LO2);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_DIGTUNE, MC44S803_ADDR) |
          MC44S803_REG_SM(1, MC44S803_DA) |
          MC44S803_REG_SM(lo1, MC44S803_LO_REF) |
          MC44S803_REG_SM(1, MC44S803_AT);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    val = MC44S803_REG_SM(MC44S803_REG_DIGTUNE, MC44S803_ADDR) |
          MC44S803_REG_SM(2, MC44S803_DA) |
          MC44S803_REG_SM(lo2, MC44S803_LO_REF) |
          MC44S803_REG_SM(1, MC44S803_AT);

    err = mc44s803_writereg(priv, val);
    if (err)
        goto exit;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    return 0;

exit:
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    mc_printk(KERN_WARNING, "I/O Error\n");
    return err;
}

static int mc44s803_get_frequency(struct dvb_frontend *fe, u32 *frequency)
{
    struct mc44s803_priv *priv = fe->tuner_priv;
    *frequency = priv->frequency;
    return 0;
}

static int mc44s803_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
{
    *frequency = MC44S803_IF2; /* 36.125 MHz */
    return 0;
}

static const struct dvb_tuner_ops mc44s803_tuner_ops = {
    .info = {
        .name           = "Freescale MC44S803",
        .frequency_min  =   48000000,
        .frequency_max  = 1000000000,
        .frequency_step =     100000,
    },

    .release       = mc44s803_release,
    .init          = mc44s803_init,
    .set_params    = mc44s803_set_params,
    .get_frequency = mc44s803_get_frequency,
    .get_if_frequency = mc44s803_get_if_frequency,
};

/* This functions tries to identify a MC44S803 tuner by reading the ID
   register. This is hasty. */
struct dvb_frontend *mc44s803_attach(struct dvb_frontend *fe,
     struct i2c_adapter *i2c, struct mc44s803_config *cfg)
{
    struct mc44s803_priv *priv;
    u32 reg;
    u8 id;
    int ret;

    reg = 0;

    priv = kzalloc(sizeof(struct mc44s803_priv), GFP_KERNEL);
    if (priv == NULL)
        return NULL;

    priv->cfg = cfg;
    priv->i2c = i2c;
    priv->fe  = fe;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */

    ret = mc44s803_readreg(priv, MC44S803_REG_ID, &reg);
    if (ret)
        goto error;

    id = MC44S803_REG_MS(reg, MC44S803_ID);

    if (id != 0x14) {
        mc_printk(KERN_ERR, "unsupported ID "
               "(%x should be 0x14)\n", id);
        goto error;
    }

    mc_printk(KERN_INFO, "successfully identified (ID = %x)\n", id);
    memcpy(&fe->ops.tuner_ops, &mc44s803_tuner_ops,
           sizeof(struct dvb_tuner_ops));

    fe->tuner_priv = priv;

    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */

    return fe;

error:
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */

    kfree(priv);
    return NULL;
}
EXPORT_SYMBOL(mc44s803_attach);

MODULE_AUTHOR("Jochen Friedrich");
MODULE_DESCRIPTION("Freescale MC44S803 silicon tuner driver");
MODULE_LICENSE("GPL");