/*
 * Driver for the ST STV6111 tuner
 *
 * Copyright (C) 2014 Digital Devices GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 only, as published by the Free Software Foundation.
 *
 * 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.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <asm/div64.h>

#include "stv6111.h"

#include "dvb_frontend.h"

struct stv {
	struct i2c_adapter *i2c;
	u8 adr;

	u8 reg[11];
	u32 ref_freq;
	u32 frequency;
};

struct slookup {
	s16 value;
	u16 reg_value;
};

static const struct slookup lnagain_nf_lookup[] = {
	/* Gain *100dB // Reg */
	{ 2572,	0 },
	{ 2575, 1 },
	{ 2580, 2 },
	{ 2588, 3 },
	{ 2596, 4 },
	{ 2611, 5 },
	{ 2633, 6 },
	{ 2664, 7 },
	{ 2701, 8 },
	{ 2753, 9 },
	{ 2816, 10 },
	{ 2902, 11 },
	{ 2995, 12 },
	{ 3104, 13 },
	{ 3215, 14 },
	{ 3337, 15 },
	{ 3492, 16 },
	{ 3614, 17 },
	{ 3731, 18 },
	{ 3861, 19 },
	{ 3988, 20 },
	{ 4124, 21 },
	{ 4253, 22 },
	{ 4386,	23 },
	{ 4505,	24 },
	{ 4623,	25 },
	{ 4726,	26 },
	{ 4821,	27 },
	{ 4903,	28 },
	{ 4979,	29 },
	{ 5045,	30 },
	{ 5102,	31 }
};

static const struct slookup lnagain_iip3_lookup[] = {
	/* Gain *100dB // reg */
	{ 1548,	0 },
	{ 1552,	1 },
	{ 1569,	2 },
	{ 1565,	3 },
	{ 1577,	4 },
	{ 1594,	5 },
	{ 1627,	6 },
	{ 1656,	7 },
	{ 1700,	8 },
	{ 1748,	9 },
	{ 1805,	10 },
	{ 1896,	11 },
	{ 1995,	12 },
	{ 2113,	13 },
	{ 2233,	14 },
	{ 2366,	15 },
	{ 2543,	16 },
	{ 2687,	17 },
	{ 2842,	18 },
	{ 2999,	19 },
	{ 3167,	20 },
	{ 3342,	21 },
	{ 3507,	22 },
	{ 3679,	23 },
	{ 3827,	24 },
	{ 3970,	25 },
	{ 4094,	26 },
	{ 4210,	27 },
	{ 4308,	28 },
	{ 4396,	29 },
	{ 4468,	30 },
	{ 4535,	31 }
};

static const struct slookup gain_rfagc_lookup[] = {
	/* Gain *100dB // reg */
	{ 4870,	0x3000 },
	{ 4850,	0x3C00 },
	{ 4800,	0x4500 },
	{ 4750,	0x4800 },
	{ 4700,	0x4B00 },
	{ 4650,	0x4D00 },
	{ 4600,	0x4F00 },
	{ 4550,	0x5100 },
	{ 4500,	0x5200 },
	{ 4420,	0x5500 },
	{ 4316,	0x5800 },
	{ 4200,	0x5B00 },
	{ 4119,	0x5D00 },
	{ 3999,	0x6000 },
	{ 3950,	0x6100 },
	{ 3876,	0x6300 },
	{ 3755,	0x6600 },
	{ 3641,	0x6900 },
	{ 3567,	0x6B00 },
	{ 3425,	0x6F00 },
	{ 3350,	0x7100 },
	{ 3236,	0x7400 },
	{ 3118,	0x7700 },
	{ 3004,	0x7A00 },
	{ 2917,	0x7C00 },
	{ 2776,	0x7F00 },
	{ 2635,	0x8200 },
	{ 2516,	0x8500 },
	{ 2406,	0x8800 },
	{ 2290,	0x8B00 },
	{ 2170,	0x8E00 },
	{ 2073,	0x9100 },
	{ 1949,	0x9400 },
	{ 1836,	0x9700 },
	{ 1712,	0x9A00 },
	{ 1631,	0x9C00 },
	{ 1515,	0x9F00 },
	{ 1400,	0xA200 },
	{ 1323,	0xA400 },
	{ 1203,	0xA700 },
	{ 1091,	0xAA00 },
	{ 1011,	0xAC00 },
	{ 904,	0xAF00 },
	{ 787,	0xB200 },
	{ 685,	0xB500 },
	{ 571,	0xB800 },
	{ 464,	0xBB00 },
	{ 374,	0xBE00 },
	{ 275,	0xC200 },
	{ 181,	0xC600 },
	{ 102,	0xCC00 },
	{ 49,	0xD900 }
};

/*
 * This table is 6 dB too low comapred to the others (probably created with
 * a different BB_MAG setting)
 */
static const struct slookup gain_channel_agc_nf_lookup[] = {
	/* Gain *100dB // reg */
	{ 7082,	0x3000 },
	{ 7052,	0x4000 },
	{ 7007,	0x4600 },
	{ 6954,	0x4A00 },
	{ 6909,	0x4D00 },
	{ 6833,	0x5100 },
	{ 6753,	0x5400 },
	{ 6659,	0x5700 },
	{ 6561,	0x5A00 },
	{ 6472,	0x5C00 },
	{ 6366,	0x5F00 },
	{ 6259,	0x6100 },
	{ 6151,	0x6400 },
	{ 6026,	0x6700 },
	{ 5920,	0x6900 },
	{ 5835,	0x6B00 },
	{ 5770,	0x6C00 },
	{ 5681,	0x6E00 },
	{ 5596,	0x7000 },
	{ 5503,	0x7200 },
	{ 5429,	0x7300 },
	{ 5319,	0x7500 },
	{ 5220,	0x7700 },
	{ 5111,	0x7900 },
	{ 4983,	0x7B00 },
	{ 4876,	0x7D00 },
	{ 4755,	0x7F00 },
	{ 4635,	0x8100 },
	{ 4499,	0x8300 },
	{ 4405,	0x8500 },
	{ 4323,	0x8600 },
	{ 4233,	0x8800 },
	{ 4156,	0x8A00 },
	{ 4038,	0x8C00 },
	{ 3935,	0x8E00 },
	{ 3823,	0x9000 },
	{ 3712,	0x9200 },
	{ 3601,	0x9500 },
	{ 3511,	0x9700 },
	{ 3413,	0x9900 },
	{ 3309,	0x9B00 },
	{ 3213,	0x9D00 },
	{ 3088,	0x9F00 },
	{ 2992,	0xA100 },
	{ 2878,	0xA400 },
	{ 2769,	0xA700 },
	{ 2645,	0xAA00 },
	{ 2538,	0xAD00 },
	{ 2441,	0xB000 },
	{ 2350,	0xB600 },
	{ 2237,	0xBA00 },
	{ 2137,	0xBF00 },
	{ 2039,	0xC500 },
	{ 1938,	0xDF00 },
	{ 1927,	0xFF00 }
};

static const struct slookup gain_channel_agc_iip3_lookup[] = {
	/* Gain *100dB // reg */
	{ 7070,	0x3000 },
	{ 7028,	0x4000 },
	{ 7019,	0x4600 },
	{ 6900,	0x4A00 },
	{ 6811,	0x4D00 },
	{ 6763,	0x5100 },
	{ 6690,	0x5400 },
	{ 6644,	0x5700 },
	{ 6617,	0x5A00 },
	{ 6598,	0x5C00 },
	{ 6462,	0x5F00 },
	{ 6348,	0x6100 },
	{ 6197,	0x6400 },
	{ 6154,	0x6700 },
	{ 6098,	0x6900 },
	{ 5893,	0x6B00 },
	{ 5812,	0x6C00 },
	{ 5773,	0x6E00 },
	{ 5723,	0x7000 },
	{ 5661,	0x7200 },
	{ 5579,	0x7300 },
	{ 5460,	0x7500 },
	{ 5308,	0x7700 },
	{ 5099,	0x7900 },
	{ 4910,	0x7B00 },
	{ 4800,	0x7D00 },
	{ 4785,	0x7F00 },
	{ 4635,	0x8100 },
	{ 4466,	0x8300 },
	{ 4314,	0x8500 },
	{ 4295,	0x8600 },
	{ 4144,	0x8800 },
	{ 3920,	0x8A00 },
	{ 3889,	0x8C00 },
	{ 3771,	0x8E00 },
	{ 3655,	0x9000 },
	{ 3446,	0x9200 },
	{ 3298,	0x9500 },
	{ 3083,	0x9700 },
	{ 3015,	0x9900 },
	{ 2833,	0x9B00 },
	{ 2746,	0x9D00 },
	{ 2632,	0x9F00 },
	{ 2598,	0xA100 },
	{ 2480,	0xA400 },
	{ 2236,	0xA700 },
	{ 2171,	0xAA00 },
	{ 2060,	0xAD00 },
	{ 1999,	0xB000 },
	{ 1974,	0xB600 },
	{ 1820,	0xBA00 },
	{ 1741,	0xBF00 },
	{ 1655,	0xC500 },
	{ 1444,	0xDF00 },
	{ 1325,	0xFF00 },
};

static inline u32 muldiv32(u32 a, u32 b, u32 c)
{
	u64 tmp64;

	tmp64 = (u64)a * (u64)b;
	do_div(tmp64, c);

	return (u32)tmp64;
}

static int i2c_read(struct i2c_adapter *adap,
		    u8 adr, u8 *msg, int len, u8 *answ, int alen)
{
	struct i2c_msg msgs[2] = { { .addr = adr, .flags = 0,
				     .buf = msg, .len = len},
				   { .addr = adr, .flags = I2C_M_RD,
				     .buf = answ, .len = alen } };
	if (i2c_transfer(adap, msgs, 2) != 2) {
		dev_err(&adap->dev, "i2c read error\n");
		return -EIO;
	}
	return 0;
}

static int i2c_write(struct i2c_adapter *adap, u8 adr, u8 *data, int len)
{
	struct i2c_msg msg = {.addr = adr, .flags = 0,
			      .buf = data, .len = len};

	if (i2c_transfer(adap, &msg, 1) != 1) {
		dev_err(&adap->dev, "i2c write error\n");
		return -EIO;
	}
	return 0;
}

static int write_regs(struct stv *state, int reg, int len)
{
	u8 d[12];

	memcpy(&d[1], &state->reg[reg], len);
	d[0] = reg;
	return i2c_write(state->i2c, state->adr, d, len + 1);
}

static int write_reg(struct stv *state, u8 reg, u8 val)
{
	u8 d[2] = {reg, val};

	return i2c_write(state->i2c, state->adr, d, 2);
}

static int read_reg(struct stv *state, u8 reg, u8 *val)
{
	return i2c_read(state->i2c, state->adr, &reg, 1, val, 1);
}

static int wait_for_call_done(struct stv *state, u8 mask)
{
	int status = 0;
	u32 lock_retry_count = 10;

	while (lock_retry_count > 0) {
		u8 regval;

		status = read_reg(state, 9, &regval);
		if (status < 0)
			return status;

		if ((regval & mask) == 0)
			break;
		usleep_range(4000, 6000);
		lock_retry_count -= 1;

		status = -EIO;
	}
	return status;
}

static void init_state(struct stv *state)
{
	u32 clkdiv = 0;
	u32 agcmode = 0;
	u32 agcref = 2;
	u32 agcset = 0xffffffff;
	u32 bbmode = 0xffffffff;

	state->reg[0] = 0x08;
	state->reg[1] = 0x41;
	state->reg[2] = 0x8f;
	state->reg[3] = 0x00;
	state->reg[4] = 0xce;
	state->reg[5] = 0x54;
	state->reg[6] = 0x55;
	state->reg[7] = 0x45;
	state->reg[8] = 0x46;
	state->reg[9] = 0xbd;
	state->reg[10] = 0x11;

	state->ref_freq = 16000;

	if (clkdiv <= 3)
		state->reg[0x00] |= (clkdiv & 0x03);
	if (agcmode <= 3) {
		state->reg[0x03] |= (agcmode << 5);
		if (agcmode == 0x01)
			state->reg[0x01] |= 0x30;
	}
	if (bbmode <= 3)
		state->reg[0x01] = (state->reg[0x01] & ~0x30) | (bbmode << 4);
	if (agcref <= 7)
		state->reg[0x03] |= agcref;
	if (agcset <= 31)
		state->reg[0x02] = (state->reg[0x02] & ~0x1F) | agcset | 0x40;
}

static int attach_init(struct stv *state)
{
	if (write_regs(state, 0, 11))
		return -ENODEV;
	return 0;
}

static void release(struct dvb_frontend *fe)
{
	kfree(fe->tuner_priv);
	fe->tuner_priv = NULL;
}

static int set_bandwidth(struct dvb_frontend *fe, u32 cutoff_frequency)
{
	struct stv *state = fe->tuner_priv;
	u32 index = (cutoff_frequency + 999999) / 1000000;

	if (index < 6)
		index = 6;
	if (index > 50)
		index = 50;
	if ((state->reg[0x08] & ~0xFC) == ((index - 6) << 2))
		return 0;

	state->reg[0x08] = (state->reg[0x08] & ~0xFC) | ((index - 6) << 2);
	state->reg[0x09] = (state->reg[0x09] & ~0x0C) | 0x08;
	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 1);
	write_regs(state, 0x08, 2);
	wait_for_call_done(state, 0x08);
	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 0);
	return 0;
}

static int set_lof(struct stv *state, u32 local_frequency, u32 cutoff_frequency)
{
	u32 index = (cutoff_frequency + 999999) / 1000000;
	u32 frequency = (local_frequency + 500) / 1000;
	u32 p = 1, psel = 0, fvco, div, frac;
	u8 icp, tmp;

	if (index < 6)
		index = 6;
	if (index > 50)
		index = 50;

	if (frequency <= 1300000) {
		p =  4;
		psel = 1;
	} else {
		p =  2;
		psel = 0;
	}
	fvco = frequency * p;
	div = fvco / state->ref_freq;
	frac = fvco % state->ref_freq;
	frac = muldiv32(frac, 0x40000, state->ref_freq);

	icp = 0;
	if (fvco < 2700000)
		icp = 0;
	else if (fvco < 2950000)
		icp = 1;
	else if (fvco < 3300000)
		icp = 2;
	else if (fvco < 3700000)
		icp = 3;
	else if (fvco < 4200000)
		icp = 5;
	else if (fvco < 4800000)
		icp = 6;
	else
		icp = 7;

	state->reg[0x02] |= 0x80; /* LNA IIP3 Mode */

	state->reg[0x03] = (state->reg[0x03] & ~0x80) | (psel << 7);
	state->reg[0x04] = (div & 0xFF);
	state->reg[0x05] = (((div >> 8) & 0x01) | ((frac & 0x7F) << 1)) & 0xff;
	state->reg[0x06] = ((frac >> 7) & 0xFF);
	state->reg[0x07] = (state->reg[0x07] & ~0x07) | ((frac >> 15) & 0x07);
	state->reg[0x07] = (state->reg[0x07] & ~0xE0) | (icp << 5);

	state->reg[0x08] = (state->reg[0x08] & ~0xFC) | ((index - 6) << 2);
	/* Start cal vco,CF */
	state->reg[0x09] = (state->reg[0x09] & ~0x0C) | 0x0C;
	write_regs(state, 2, 8);

	wait_for_call_done(state, 0x0C);

	usleep_range(10000, 12000);

	read_reg(state, 0x03, &tmp);
	if (tmp & 0x10)	{
		state->reg[0x02] &= ~0x80; /* LNA NF Mode */
		write_regs(state, 2, 1);
	}
	read_reg(state, 0x08, &tmp);

	state->frequency = frequency;

	return 0;
}

static int set_params(struct dvb_frontend *fe)
{
	struct stv *state = fe->tuner_priv;
	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
	u32 freq, cutoff;

	if (p->delivery_system != SYS_DVBS && p->delivery_system != SYS_DVBS2)
		return -EINVAL;

	freq = p->frequency * 1000;
	cutoff = 5000000 + muldiv32(p->symbol_rate, 135, 200);

	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 1);
	set_lof(state, freq, cutoff);
	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 0);
	return 0;
}

static s32 table_lookup(const struct slookup *table,
			int table_size, u16 reg_value)
{
	s32 gain;
	s32 reg_diff;
	int imin = 0;
	int imax = table_size - 1;
	int i;

	/* Assumes Table[0].RegValue < Table[imax].RegValue */
	if (reg_value <= table[0].reg_value) {
		gain = table[0].value;
	} else if (reg_value >= table[imax].reg_value) {
		gain = table[imax].value;
	} else {
		while ((imax - imin) > 1) {
			i = (imax + imin) / 2;
			if ((table[imin].reg_value <= reg_value) &&
			    (reg_value <= table[i].reg_value))
				imax = i;
			else
				imin = i;
		}
		reg_diff = table[imax].reg_value - table[imin].reg_value;
		gain = table[imin].value;
		if (reg_diff != 0)
			gain += ((s32)(reg_value - table[imin].reg_value) *
				(s32)(table[imax].value
				- table[imin].value)) / reg_diff;
	}
	return gain;
}

static int get_rf_strength(struct dvb_frontend *fe, u16 *st)
{
	struct stv *state = fe->tuner_priv;
	u16 rfagc = *st;
	s32 gain;

	if ((state->reg[0x03] & 0x60) == 0) {
		/* RF Mode, Read AGC ADC */
		u8 reg = 0;

		if (fe->ops.i2c_gate_ctrl)
			fe->ops.i2c_gate_ctrl(fe, 1);
		write_reg(state, 0x02, state->reg[0x02] | 0x20);
		read_reg(state, 2, &reg);
		if (reg & 0x20)
			read_reg(state, 2, &reg);
		if (fe->ops.i2c_gate_ctrl)
			fe->ops.i2c_gate_ctrl(fe, 0);

		if ((state->reg[0x02] & 0x80) == 0)
			/* NF */
			gain = table_lookup(lnagain_nf_lookup,
					    ARRAY_SIZE(lnagain_nf_lookup),
					    reg & 0x1F);
		else
			/* IIP3 */
			gain = table_lookup(lnagain_iip3_lookup,
					    ARRAY_SIZE(lnagain_iip3_lookup),
					    reg & 0x1F);

		gain += table_lookup(gain_rfagc_lookup,
				     ARRAY_SIZE(gain_rfagc_lookup), rfagc);

		gain -= 2400;
	} else {
		/* Channel Mode */
		if ((state->reg[0x02] & 0x80) == 0) {
			/* NF */
			gain = table_lookup(
				gain_channel_agc_nf_lookup,
				ARRAY_SIZE(gain_channel_agc_nf_lookup), rfagc);

			gain += 600;
		} else {
			/* IIP3 */
			gain = table_lookup(
				gain_channel_agc_iip3_lookup,
				ARRAY_SIZE(gain_channel_agc_iip3_lookup),
				rfagc);
		}
	}

	if (state->frequency > 0)
		/* Tilt correction ( 0.00016 dB/MHz ) */
		gain -= ((((s32)(state->frequency / 1000) - 1550) * 2) / 12);

	/* + (BBGain * 10); */
	gain +=  (s32)((state->reg[0x01] & 0xC0) >> 6) * 600 - 1300;

	if (gain < 0)
		gain = 0;
	else if (gain > 10000)
		gain = 10000;

	*st = 10000 - gain;

	return 0;
}

static const struct dvb_tuner_ops tuner_ops = {
	.info = {
		.name		= "ST STV6111",
		.frequency_min	= 950000,
		.frequency_max	= 2150000,
		.frequency_step	= 0
	},
	.set_params		= set_params,
	.release		= release,
	.get_rf_strength	= get_rf_strength,
	.set_bandwidth		= set_bandwidth,
};

struct dvb_frontend *stv6111_attach(struct dvb_frontend *fe,
				    struct i2c_adapter *i2c, u8 adr)
{
	struct stv *state;
	int stat;

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (!state)
		return NULL;
	state->adr = adr;
	state->i2c = i2c;
	memcpy(&fe->ops.tuner_ops, &tuner_ops, sizeof(struct dvb_tuner_ops));
	init_state(state);

	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 1);
	stat = attach_init(state);
	if (fe->ops.i2c_gate_ctrl)
		fe->ops.i2c_gate_ctrl(fe, 0);
	if (stat < 0) {
		kfree(state);
		return NULL;
	}
	fe->tuner_priv = state;
	return fe;
}
EXPORT_SYMBOL_GPL(stv6111_attach);

MODULE_DESCRIPTION("ST STV6111 satellite tuner driver");
MODULE_AUTHOR("Ralph Metzler, Manfred Voelkel");
MODULE_LICENSE("GPL");