zl10039.c

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/*
 *  Driver for Zarlink ZL10039 DVB-S tuner
 *
 *  Copyright 2007 Jan D. Louw <[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/init.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/dvb/frontend.h>

#include "dvb_frontend.h"
#include "zl10039.h"

static int debug;

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

enum zl10039_model_id {
    ID_ZL10039 = 1
};

struct zl10039_state {
    struct i2c_adapter *i2c;
    u8 i2c_addr;
    u8 id;
};

enum zl10039_reg_addr {
    PLL0 = 0,
    PLL1,
    PLL2,
    PLL3,
    RFFE,
    BASE0,
    BASE1,
    BASE2,
    LO0,
    LO1,
    LO2,
    LO3,
    LO4,
    LO5,
    LO6,
    GENERAL
};

static int zl10039_read(const struct zl10039_state *state,
            const enum zl10039_reg_addr reg, u8 *buf,
            const size_t count)
{
    u8 regbuf[] = { reg };
    struct i2c_msg msg[] = {
        {/* Write register address */
            .addr = state->i2c_addr,
            .flags = 0,
            .buf = regbuf,
            .len = 1,
        }, {/* Read count bytes */
            .addr = state->i2c_addr,
            .flags = I2C_M_RD,
            .buf = buf,
            .len = count,
        },
    };

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

    if (i2c_transfer(state->i2c, msg, 2) != 2) {
        dprintk("%s: i2c read error\n", __func__);
        return -EREMOTEIO;
    }

    return 0; /* Success */
}

static int zl10039_write(struct zl10039_state *state,
            const enum zl10039_reg_addr reg, const u8 *src,
            const size_t count)
{
    u8 buf[count + 1];
    struct i2c_msg msg = {
        .addr = state->i2c_addr,
        .flags = 0,
        .buf = buf,
        .len = count + 1,
    };

    dprintk("%s\n", __func__);
    /* Write register address and data in one go */
    buf[0] = reg;
    memcpy(&buf[1], src, count);
    if (i2c_transfer(state->i2c, &msg, 1) != 1) {
        dprintk("%s: i2c write error\n", __func__);
        return -EREMOTEIO;
    }

    return 0; /* Success */
}

static inline int zl10039_readreg(struct zl10039_state *state,
                const enum zl10039_reg_addr reg, u8 *val)
{
    return zl10039_read(state, reg, val, 1);
}

static inline int zl10039_writereg(struct zl10039_state *state,
                const enum zl10039_reg_addr reg,
                const u8 val)
{
    return zl10039_write(state, reg, &val, 1);
}

static int zl10039_init(struct dvb_frontend *fe)
{
    struct zl10039_state *state = fe->tuner_priv;
    int ret;

    dprintk("%s\n", __func__);
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);
    /* Reset logic */
    ret = zl10039_writereg(state, GENERAL, 0x40);
    if (ret < 0) {
        dprintk("Note: i2c write error normal when resetting the "
            "tuner\n");
    }
    /* Wake up */
    ret = zl10039_writereg(state, GENERAL, 0x01);
    if (ret < 0) {
        dprintk("Tuner power up failed\n");
        return ret;
    }
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    return 0;
}

static int zl10039_sleep(struct dvb_frontend *fe)
{
    struct zl10039_state *state = fe->tuner_priv;
    int ret;

    dprintk("%s\n", __func__);
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);
    ret = zl10039_writereg(state, GENERAL, 0x80);
    if (ret < 0) {
        dprintk("Tuner sleep failed\n");
        return ret;
    }
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    return 0;
}

static int zl10039_set_params(struct dvb_frontend *fe)
{
    struct dtv_frontend_properties *c = &fe->dtv_property_cache;
    struct zl10039_state *state = fe->tuner_priv;
    u8 buf[6];
    u8 bf;
    u32 fbw;
    u32 div;
    int ret;

    dprintk("%s\n", __func__);
    dprintk("Set frequency = %d, symbol rate = %d\n",
            c->frequency, c->symbol_rate);

    /* Assumed 10.111 MHz crystal oscillator */
    /* Cancelled num/den 80 to prevent overflow */
    div = (c->frequency * 1000) / 126387;
    fbw = (c->symbol_rate * 27) / 32000;
    /* Cancelled num/den 10 to prevent overflow */
    bf = ((fbw * 5088) / 1011100) - 1;

    /*PLL divider*/
    buf[0] = (div >> 8) & 0x7f;
    buf[1] = (div >> 0) & 0xff;
    /*Reference divider*/
    /* Select reference ratio of 80 */
    buf[2] = 0x1D;
    /*PLL test modes*/
    buf[3] = 0x40;
    /*RF Control register*/
    buf[4] = 0x6E; /* Bypass enable */
    /*Baseband filter cutoff */
    buf[5] = bf;

    /* Open i2c gate */
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);
    /* BR = 10, Enable filter adjustment */
    ret = zl10039_writereg(state, BASE1, 0x0A);
    if (ret < 0)
        goto error;
    /* Write new config values */
    ret = zl10039_write(state, PLL0, buf, sizeof(buf));
    if (ret < 0)
        goto error;
    /* BR = 10, Disable filter adjustment */
    ret = zl10039_writereg(state, BASE1, 0x6A);
    if (ret < 0)
        goto error;

    /* Close i2c gate */
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);
    return 0;
error:
    dprintk("Error setting tuner\n");
    return ret;
}

static int zl10039_release(struct dvb_frontend *fe)
{
    struct zl10039_state *state = fe->tuner_priv;

    dprintk("%s\n", __func__);
    kfree(state);
    fe->tuner_priv = NULL;
    return 0;
}

static struct dvb_tuner_ops zl10039_ops = {
    .release = zl10039_release,
    .init = zl10039_init,
    .sleep = zl10039_sleep,
    .set_params = zl10039_set_params,
};

struct dvb_frontend *zl10039_attach(struct dvb_frontend *fe,
        u8 i2c_addr, struct i2c_adapter *i2c)
{
    struct zl10039_state *state = NULL;

    dprintk("%s\n", __func__);
    state = kmalloc(sizeof(struct zl10039_state), GFP_KERNEL);
    if (state == NULL)
        goto error;

    state->i2c = i2c;
    state->i2c_addr = i2c_addr;

    /* Open i2c gate */
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 1);
    /* check if this is a valid tuner */
    if (zl10039_readreg(state, GENERAL, &state->id) < 0) {
        /* Close i2c gate */
        if (fe->ops.i2c_gate_ctrl)
            fe->ops.i2c_gate_ctrl(fe, 0);
        goto error;
    }
    /* Close i2c gate */
    if (fe->ops.i2c_gate_ctrl)
        fe->ops.i2c_gate_ctrl(fe, 0);

    state->id = state->id & 0x0f;
    switch (state->id) {
    case ID_ZL10039:
        strcpy(fe->ops.tuner_ops.info.name,
            "Zarlink ZL10039 DVB-S tuner");
        break;
    default:
        dprintk("Chip ID=%x does not match a known type\n", state->id);
        goto error;
    }

    memcpy(&fe->ops.tuner_ops, &zl10039_ops, sizeof(struct dvb_tuner_ops));
    fe->tuner_priv = state;
    dprintk("Tuner attached @ i2c address 0x%02x\n", i2c_addr);
    return fe;
error:
    kfree(state);
    return NULL;
}
EXPORT_SYMBOL(zl10039_attach);

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
MODULE_DESCRIPTION("Zarlink ZL10039 DVB-S tuner driver");
MODULE_AUTHOR("Jan D. Louw <[email protected]>");
MODULE_LICENSE("GPL");