text: /*
   * Realtek RTL2830 DVB-T demodulator driver
   *
   * Copyright (C) 2011 Antti Palosaari <crope@iki.fi>
   *
   *    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.
   *
   */
  
  #include "rtl2830_priv.h"
  
  /* Our regmap is bypassing I2C adapter lock, thus we do it! */
  static int rtl2830_bulk_write(struct i2c_client *client, unsigned int reg,
  			      const void *val, size_t val_count)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  
  	i2c_lock_adapter(client->adapter);
  	ret = regmap_bulk_write(dev->regmap, reg, val, val_count);
  	i2c_unlock_adapter(client->adapter);
  	return ret;
  }
  
  static int rtl2830_update_bits(struct i2c_client *client, unsigned int reg,
  			       unsigned int mask, unsigned int val)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  
  	i2c_lock_adapter(client->adapter);
  	ret = regmap_update_bits(dev->regmap, reg, mask, val);
  	i2c_unlock_adapter(client->adapter);
  	return ret;
  }
  
  static int rtl2830_bulk_read(struct i2c_client *client, unsigned int reg,
  			     void *val, size_t val_count)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  
  	i2c_lock_adapter(client->adapter);
  	ret = regmap_bulk_read(dev->regmap, reg, val, val_count);
  	i2c_unlock_adapter(client->adapter);
  	return ret;
  }
  
  static int rtl2830_init(struct dvb_frontend *fe)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	struct dtv_frontend_properties *c = &dev->fe.dtv_property_cache;
  	int ret, i;
  	struct rtl2830_reg_val_mask tab[] = {
  		{0x00d, 0x01, 0x03},
  		{0x00d, 0x10, 0x10},
  		{0x104, 0x00, 0x1e},
  		{0x105, 0x80, 0x80},
  		{0x110, 0x02, 0x03},
  		{0x110, 0x08, 0x0c},
  		{0x17b, 0x00, 0x40},
  		{0x17d, 0x05, 0x0f},
  		{0x17d, 0x50, 0xf0},
  		{0x18c, 0x08, 0x0f},
  		{0x18d, 0x00, 0xc0},
  		{0x188, 0x05, 0x0f},
  		{0x189, 0x00, 0xfc},
  		{0x2d5, 0x02, 0x02},
  		{0x2f1, 0x02, 0x06},
  		{0x2f1, 0x20, 0xf8},
  		{0x16d, 0x00, 0x01},
  		{0x1a6, 0x00, 0x80},
  		{0x106, dev->pdata->vtop, 0x3f},
  		{0x107, dev->pdata->krf, 0x3f},
  		{0x112, 0x28, 0xff},
  		{0x103, dev->pdata->agc_targ_val, 0xff},
  		{0x00a, 0x02, 0x07},
  		{0x140, 0x0c, 0x3c},
  		{0x140, 0x40, 0xc0},
  		{0x15b, 0x05, 0x07},
  		{0x15b, 0x28, 0x38},
  		{0x15c, 0x05, 0x07},
  		{0x15c, 0x28, 0x38},
  		{0x115, dev->pdata->spec_inv, 0x01},
  		{0x16f, 0x01, 0x07},
  		{0x170, 0x18, 0x38},
  		{0x172, 0x0f, 0x0f},
  		{0x173, 0x08, 0x38},
  		{0x175, 0x01, 0x07},
  		{0x176, 0x00, 0xc0},
  	};
  
  	for (i = 0; i < ARRAY_SIZE(tab); i++) {
  		ret = rtl2830_update_bits(client, tab[i].reg, tab[i].mask,
  					  tab[i].val);
  		if (ret)
  			goto err;
  	}
  
  	ret = rtl2830_bulk_write(client, 0x18f, "\x28\x00", 2);
  	if (ret)
  		goto err;
  
  	ret = rtl2830_bulk_write(client, 0x195,
  				 "\x04\x06\x0a\x12\x0a\x12\x1e\x28", 8);
  	if (ret)
  		goto err;
  
  	/* TODO: spec init */
  
  	/* soft reset */
  	ret = rtl2830_update_bits(client, 0x101, 0x04, 0x04);
  	if (ret)
  		goto err;
  
  	ret = rtl2830_update_bits(client, 0x101, 0x04, 0x00);
  	if (ret)
  		goto err;
  
  	/* init stats here in order signal app which stats are supported */
  	c->strength.len = 1;
  	c->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	c->cnr.len = 1;
  	c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	c->post_bit_error.len = 1;
  	c->post_bit_error.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	c->post_bit_count.len = 1;
  	c->post_bit_count.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	/* start statistics polling */
  	schedule_delayed_work(&dev->stat_work, msecs_to_jiffies(2000));
  
  	dev->sleeping = false;
  
  	return ret;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_sleep(struct dvb_frontend *fe)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  
  	dev->sleeping = true;
  	/* stop statistics polling */
  	cancel_delayed_work_sync(&dev->stat_work);
  	dev->fe_status = 0;
  
  	return 0;
  }
  
  static int rtl2830_get_tune_settings(struct dvb_frontend *fe,
  				     struct dvb_frontend_tune_settings *s)
  {
  	s->min_delay_ms = 500;
  	s->step_size = fe->ops.info.frequency_stepsize * 2;
  	s->max_drift = (fe->ops.info.frequency_stepsize * 2) + 1;
  
  	return 0;
  }
  
  static int rtl2830_set_frontend(struct dvb_frontend *fe)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
  	int ret, i;
  	u64 num;
  	u8 buf[3], u8tmp;
  	u32 if_ctl, if_frequency;
  	static const u8 bw_params1[3][34] = {
  		{
  		0x1f, 0xf0, 0x1f, 0xf0, 0x1f, 0xfa, 0x00, 0x17, 0x00, 0x41,
  		0x00, 0x64, 0x00, 0x67, 0x00, 0x38, 0x1f, 0xde, 0x1f, 0x7a,
  		0x1f, 0x47, 0x1f, 0x7c, 0x00, 0x30, 0x01, 0x4b, 0x02, 0x82,
  		0x03, 0x73, 0x03, 0xcf, /* 6 MHz */
  		}, {
  		0x1f, 0xfa, 0x1f, 0xda, 0x1f, 0xc1, 0x1f, 0xb3, 0x1f, 0xca,
  		0x00, 0x07, 0x00, 0x4d, 0x00, 0x6d, 0x00, 0x40, 0x1f, 0xca,
  		0x1f, 0x4d, 0x1f, 0x2a, 0x1f, 0xb2, 0x00, 0xec, 0x02, 0x7e,
  		0x03, 0xd0, 0x04, 0x53, /* 7 MHz */
  		}, {
  		0x00, 0x10, 0x00, 0x0e, 0x1f, 0xf7, 0x1f, 0xc9, 0x1f, 0xa0,
  		0x1f, 0xa6, 0x1f, 0xec, 0x00, 0x4e, 0x00, 0x7d, 0x00, 0x3a,
  		0x1f, 0x98, 0x1f, 0x10, 0x1f, 0x40, 0x00, 0x75, 0x02, 0x5f,
  		0x04, 0x24, 0x04, 0xdb, /* 8 MHz */
  		},
  	};
  	static const u8 bw_params2[3][6] = {
  		{0xc3, 0x0c, 0x44, 0x33, 0x33, 0x30}, /* 6 MHz */
  		{0xb8, 0xe3, 0x93, 0x99, 0x99, 0x98}, /* 7 MHz */
  		{0xae, 0xba, 0xf3, 0x26, 0x66, 0x64}, /* 8 MHz */
  	};
  
  	dev_dbg(&client->dev, "frequency=%u bandwidth_hz=%u inversion=%u\n",
  		c->frequency, c->bandwidth_hz, c->inversion);
  
  	/* program tuner */
  	if (fe->ops.tuner_ops.set_params)
  		fe->ops.tuner_ops.set_params(fe);
  
  	switch (c->bandwidth_hz) {
  	case 6000000:
  		i = 0;
  		break;
  	case 7000000:
  		i = 1;
  		break;
  	case 8000000:
  		i = 2;
  		break;
  	default:
  		dev_err(&client->dev, "invalid bandwidth_hz %u\n",
  			c->bandwidth_hz);
  		return -EINVAL;
  	}
  
  	ret = rtl2830_update_bits(client, 0x008, 0x06, i << 1);
  	if (ret)
  		goto err;
  
  	/* program if frequency */
  	if (fe->ops.tuner_ops.get_if_frequency)
  		ret = fe->ops.tuner_ops.get_if_frequency(fe, &if_frequency);
  	else
  		ret = -EINVAL;
  	if (ret)
  		goto err;
  
  	num = if_frequency % dev->pdata->clk;
  	num *= 0x400000;
  	num = div_u64(num, dev->pdata->clk);
  	num = -num;
  	if_ctl = num & 0x3fffff;
  	dev_dbg(&client->dev, "if_frequency=%d if_ctl=%08x\n",
  		if_frequency, if_ctl);
  
  	buf[0] = (if_ctl >> 16) & 0x3f;
  	buf[1] = (if_ctl >>  8) & 0xff;
  	buf[2] = (if_ctl >>  0) & 0xff;
  
  	ret = rtl2830_bulk_read(client, 0x119, &u8tmp, 1);
  	if (ret)
  		goto err;
  
  	buf[0] |= u8tmp & 0xc0;  /* [7:6] */
  
  	ret = rtl2830_bulk_write(client, 0x119, buf, 3);
  	if (ret)
  		goto err;
  
  	/* 1/2 split I2C write */
  	ret = rtl2830_bulk_write(client, 0x11c, &bw_params1[i][0], 17);
  	if (ret)
  		goto err;
  
  	/* 2/2 split I2C write */
  	ret = rtl2830_bulk_write(client, 0x12d, &bw_params1[i][17], 17);
  	if (ret)
  		goto err;
  
  	ret = rtl2830_bulk_write(client, 0x19d, bw_params2[i], 6);
  	if (ret)
  		goto err;
  
  	return ret;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_get_frontend(struct dvb_frontend *fe,
  				struct dtv_frontend_properties *c)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  	u8 buf[3];
  
  	if (dev->sleeping)
  		return 0;
  
  	ret = rtl2830_bulk_read(client, 0x33c, buf, 2);
  	if (ret)
  		goto err;
  
  	ret = rtl2830_bulk_read(client, 0x351, &buf[2], 1);
  	if (ret)
  		goto err;
  
  	dev_dbg(&client->dev, "TPS=%*ph\n", 3, buf);
  
  	switch ((buf[0] >> 2) & 3) {
  	case 0:
  		c->modulation = QPSK;
  		break;
  	case 1:
  		c->modulation = QAM_16;
  		break;
  	case 2:
  		c->modulation = QAM_64;
  		break;
  	}
  
  	switch ((buf[2] >> 2) & 1) {
  	case 0:
  		c->transmission_mode = TRANSMISSION_MODE_2K;
  		break;
  	case 1:
  		c->transmission_mode = TRANSMISSION_MODE_8K;
  	}
  
  	switch ((buf[2] >> 0) & 3) {
  	case 0:
  		c->guard_interval = GUARD_INTERVAL_1_32;
  		break;
  	case 1:
  		c->guard_interval = GUARD_INTERVAL_1_16;
  		break;
  	case 2:
  		c->guard_interval = GUARD_INTERVAL_1_8;
  		break;
  	case 3:
  		c->guard_interval = GUARD_INTERVAL_1_4;
  		break;
  	}
  
  	switch ((buf[0] >> 4) & 7) {
  	case 0:
  		c->hierarchy = HIERARCHY_NONE;
  		break;
  	case 1:
  		c->hierarchy = HIERARCHY_1;
  		break;
  	case 2:
  		c->hierarchy = HIERARCHY_2;
  		break;
  	case 3:
  		c->hierarchy = HIERARCHY_4;
  		break;
  	}
  
  	switch ((buf[1] >> 3) & 7) {
  	case 0:
  		c->code_rate_HP = FEC_1_2;
  		break;
  	case 1:
  		c->code_rate_HP = FEC_2_3;
  		break;
  	case 2:
  		c->code_rate_HP = FEC_3_4;
  		break;
  	case 3:
  		c->code_rate_HP = FEC_5_6;
  		break;
  	case 4:
  		c->code_rate_HP = FEC_7_8;
  		break;
  	}
  
  	switch ((buf[1] >> 0) & 7) {
  	case 0:
  		c->code_rate_LP = FEC_1_2;
  		break;
  	case 1:
  		c->code_rate_LP = FEC_2_3;
  		break;
  	case 2:
  		c->code_rate_LP = FEC_3_4;
  		break;
  	case 3:
  		c->code_rate_LP = FEC_5_6;
  		break;
  	case 4:
  		c->code_rate_LP = FEC_7_8;
  		break;
  	}
  
  	return 0;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_read_status(struct dvb_frontend *fe, enum fe_status *status)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  	u8 u8tmp;
  
  	*status = 0;
  
  	if (dev->sleeping)
  		return 0;
  
  	ret = rtl2830_bulk_read(client, 0x351, &u8tmp, 1);
  	if (ret)
  		goto err;
  
  	u8tmp = (u8tmp >> 3) & 0x0f; /* [6:3] */
  	if (u8tmp == 11) {
  		*status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
  			FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
  	} else if (u8tmp == 10) {
  		*status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
  			FE_HAS_VITERBI;
  	}
  
  	dev->fe_status = *status;
  
  	return ret;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_read_snr(struct dvb_frontend *fe, u16 *snr)
  {
  	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
  
  	if (c->cnr.stat[0].scale == FE_SCALE_DECIBEL)
  		*snr = div_s64(c->cnr.stat[0].svalue, 100);
  	else
  		*snr = 0;
  
  	return 0;
  }
  
  static int rtl2830_read_ber(struct dvb_frontend *fe, u32 *ber)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  
  	*ber = (dev->post_bit_error - dev->post_bit_error_prev);
  	dev->post_bit_error_prev = dev->post_bit_error;
  
  	return 0;
  }
  
  static int rtl2830_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
  {
  	*ucblocks = 0;
  
  	return 0;
  }
  
  static int rtl2830_read_signal_strength(struct dvb_frontend *fe, u16 *strength)
  {
  	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
  
  	if (c->strength.stat[0].scale == FE_SCALE_RELATIVE)
  		*strength = c->strength.stat[0].uvalue;
  	else
  		*strength = 0;
  
  	return 0;
  }
  
  static struct dvb_frontend_ops rtl2830_ops = {
  	.delsys = {SYS_DVBT},
  	.info = {
  		.name = "Realtek RTL2830 (DVB-T)",
  		.caps = FE_CAN_FEC_1_2 |
  			FE_CAN_FEC_2_3 |
  			FE_CAN_FEC_3_4 |
  			FE_CAN_FEC_5_6 |
  			FE_CAN_FEC_7_8 |
  			FE_CAN_FEC_AUTO |
  			FE_CAN_QPSK |
  			FE_CAN_QAM_16 |
  			FE_CAN_QAM_64 |
  			FE_CAN_QAM_AUTO |
  			FE_CAN_TRANSMISSION_MODE_AUTO |
  			FE_CAN_GUARD_INTERVAL_AUTO |
  			FE_CAN_HIERARCHY_AUTO |
  			FE_CAN_RECOVER |
  			FE_CAN_MUTE_TS
  	},
  
  	.init = rtl2830_init,
  	.sleep = rtl2830_sleep,
  
  	.get_tune_settings = rtl2830_get_tune_settings,
  
  	.set_frontend = rtl2830_set_frontend,
  	.get_frontend = rtl2830_get_frontend,
  
  	.read_status = rtl2830_read_status,
  	.read_snr = rtl2830_read_snr,
  	.read_ber = rtl2830_read_ber,
  	.read_ucblocks = rtl2830_read_ucblocks,
  	.read_signal_strength = rtl2830_read_signal_strength,
  };
  
  static void rtl2830_stat_work(struct work_struct *work)
  {
  	struct rtl2830_dev *dev = container_of(work, struct rtl2830_dev, stat_work.work);
  	struct i2c_client *client = dev->client;
  	struct dtv_frontend_properties *c = &dev->fe.dtv_property_cache;
  	int ret, tmp;
  	u8 u8tmp, buf[2];
  	u16 u16tmp;
  
  	dev_dbg(&client->dev, "\n");
  
  	/* signal strength */
  	if (dev->fe_status & FE_HAS_SIGNAL) {
  		struct {signed int x:14; } s;
  
  		/* read IF AGC */
  		ret = rtl2830_bulk_read(client, 0x359, buf, 2);
  		if (ret)
  			goto err;
  
  		u16tmp = buf[0] << 8 | buf[1] << 0;
  		u16tmp &= 0x3fff; /* [13:0] */
  		tmp = s.x = u16tmp; /* 14-bit bin to 2 complement */
  		u16tmp = clamp_val(-4 * tmp + 32767, 0x0000, 0xffff);
  
  		dev_dbg(&client->dev, "IF AGC=%d\n", tmp);
  
  		c->strength.stat[0].scale = FE_SCALE_RELATIVE;
  		c->strength.stat[0].uvalue = u16tmp;
  	} else {
  		c->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	}
  
  	/* CNR */
  	if (dev->fe_status & FE_HAS_VITERBI) {
  		unsigned hierarchy, constellation;
  		#define CONSTELLATION_NUM 3
  		#define HIERARCHY_NUM 4
  		static const u32 constant[CONSTELLATION_NUM][HIERARCHY_NUM] = {
  			{70705899, 70705899, 70705899, 70705899},
  			{82433173, 82433173, 87483115, 94445660},
  			{92888734, 92888734, 95487525, 99770748},
  		};
  
  		ret = rtl2830_bulk_read(client, 0x33c, &u8tmp, 1);
  		if (ret)
  			goto err;
  
  		constellation = (u8tmp >> 2) & 0x03; /* [3:2] */
  		if (constellation > CONSTELLATION_NUM - 1)
  			goto err_schedule_delayed_work;
  
  		hierarchy = (u8tmp >> 4) & 0x07; /* [6:4] */
  		if (hierarchy > HIERARCHY_NUM - 1)
  			goto err_schedule_delayed_work;
  
  		ret = rtl2830_bulk_read(client, 0x40c, buf, 2);
  		if (ret)
  			goto err;
  
  		u16tmp = buf[0] << 8 | buf[1] << 0;
  		if (u16tmp)
  			tmp = (constant[constellation][hierarchy] -
  			       intlog10(u16tmp)) / ((1 << 24) / 10000);
  		else
  			tmp = 0;
  
  		dev_dbg(&client->dev, "CNR raw=%u\n", u16tmp);
  
  		c->cnr.stat[0].scale = FE_SCALE_DECIBEL;
  		c->cnr.stat[0].svalue = tmp;
  	} else {
  		c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	}
  
  	/* BER */
  	if (dev->fe_status & FE_HAS_LOCK) {
  		ret = rtl2830_bulk_read(client, 0x34e, buf, 2);
  		if (ret)
  			goto err;
  
  		u16tmp = buf[0] << 8 | buf[1] << 0;
  		dev->post_bit_error += u16tmp;
  		dev->post_bit_count += 1000000;
  
  		dev_dbg(&client->dev, "BER errors=%u total=1000000\n", u16tmp);
  
  		c->post_bit_error.stat[0].scale = FE_SCALE_COUNTER;
  		c->post_bit_error.stat[0].uvalue = dev->post_bit_error;
  		c->post_bit_count.stat[0].scale = FE_SCALE_COUNTER;
  		c->post_bit_count.stat[0].uvalue = dev->post_bit_count;
  	} else {
  		c->post_bit_error.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  		c->post_bit_count.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
  	}
  
  err_schedule_delayed_work:
  	schedule_delayed_work(&dev->stat_work, msecs_to_jiffies(2000));
  	return;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  }
  
  static int rtl2830_pid_filter_ctrl(struct dvb_frontend *fe, int onoff)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	int ret;
  	u8 u8tmp;
  
  	dev_dbg(&client->dev, "onoff=%d\n", onoff);
  
  	/* enable / disable PID filter */
  	if (onoff)
  		u8tmp = 0x80;
  	else
  		u8tmp = 0x00;
  
  	ret = rtl2830_update_bits(client, 0x061, 0x80, u8tmp);
  	if (ret)
  		goto err;
  
  	return 0;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_pid_filter(struct dvb_frontend *fe, u8 index, u16 pid, int onoff)
  {
  	struct i2c_client *client = fe->demodulator_priv;
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  	u8 buf[4];
  
  	dev_dbg(&client->dev, "index=%d pid=%04x onoff=%d\n",
  		index, pid, onoff);
  
  	/* skip invalid PIDs (0x2000) */
  	if (pid > 0x1fff || index > 32)
  		return 0;
  
  	if (onoff)
  		set_bit(index, &dev->filters);
  	else
  		clear_bit(index, &dev->filters);
  
  	/* enable / disable PIDs */
  	buf[0] = (dev->filters >>  0) & 0xff;
  	buf[1] = (dev->filters >>  8) & 0xff;
  	buf[2] = (dev->filters >> 16) & 0xff;
  	buf[3] = (dev->filters >> 24) & 0xff;
  	ret = rtl2830_bulk_write(client, 0x062, buf, 4);
  	if (ret)
  		goto err;
  
  	/* add PID */
  	buf[0] = (pid >> 8) & 0xff;
  	buf[1] = (pid >> 0) & 0xff;
  	ret = rtl2830_bulk_write(client, 0x066 + 2 * index, buf, 2);
  	if (ret)
  		goto err;
  
  	return 0;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  /*
   * I2C gate/mux/repeater logic
   * We must use unlocked __i2c_transfer() here (through regmap) because of I2C
   * adapter lock is already taken by tuner driver.
   * Gate is closed automatically after single I2C transfer.
   */
  static int rtl2830_select(struct i2c_mux_core *muxc, u32 chan_id)
  {
  	struct i2c_client *client = i2c_mux_priv(muxc);
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  	int ret;
  
  	dev_dbg(&client->dev, "\n");
  
  	/* open I2C repeater for 1 transfer, closes automatically */
  	/* XXX: regmap_update_bits() does not lock I2C adapter */
  	ret = regmap_update_bits(dev->regmap, 0x101, 0x08, 0x08);
  	if (ret)
  		goto err;
  
  	return 0;
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static struct dvb_frontend *rtl2830_get_dvb_frontend(struct i2c_client *client)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  
  	dev_dbg(&client->dev, "\n");
  
  	return &dev->fe;
  }
  
  static struct i2c_adapter *rtl2830_get_i2c_adapter(struct i2c_client *client)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  
  	dev_dbg(&client->dev, "\n");
  
  	return dev->muxc->adapter[0];
  }
  
  /*
   * We implement own I2C access routines for regmap in order to get manual access
   * to I2C adapter lock, which is needed for I2C mux adapter.
   */
  static int rtl2830_regmap_read(void *context, const void *reg_buf,
  			       size_t reg_size, void *val_buf, size_t val_size)
  {
  	struct i2c_client *client = context;
  	int ret;
  	struct i2c_msg msg[2] = {
  		{
  			.addr = client->addr,
  			.flags = 0,
  			.len = reg_size,
  			.buf = (u8 *)reg_buf,
  		}, {
  			.addr = client->addr,
  			.flags = I2C_M_RD,
  			.len = val_size,
  			.buf = val_buf,
  		}
  	};
  
  	ret = __i2c_transfer(client->adapter, msg, 2);
  	if (ret != 2) {
  		dev_warn(&client->dev, "i2c reg read failed %d\n", ret);
  		if (ret >= 0)
  			ret = -EREMOTEIO;
  		return ret;
  	}
  	return 0;
  }
  
  static int rtl2830_regmap_write(void *context, const void *data, size_t count)
  {
  	struct i2c_client *client = context;
  	int ret;
  	struct i2c_msg msg[1] = {
  		{
  			.addr = client->addr,
  			.flags = 0,
  			.len = count,
  			.buf = (u8 *)data,
  		}
  	};
  
  	ret = __i2c_transfer(client->adapter, msg, 1);
  	if (ret != 1) {
  		dev_warn(&client->dev, "i2c reg write failed %d\n", ret);
  		if (ret >= 0)
  			ret = -EREMOTEIO;
  		return ret;
  	}
  	return 0;
  }
  
  static int rtl2830_regmap_gather_write(void *context, const void *reg,
  				       size_t reg_len, const void *val,
  				       size_t val_len)
  {
  	struct i2c_client *client = context;
  	int ret;
  	u8 buf[256];
  	struct i2c_msg msg[1] = {
  		{
  			.addr = client->addr,
  			.flags = 0,
  			.len = 1 + val_len,
  			.buf = buf,
  		}
  	};
  
  	buf[0] = *(u8 const *)reg;
  	memcpy(&buf[1], val, val_len);
  
  	ret = __i2c_transfer(client->adapter, msg, 1);
  	if (ret != 1) {
  		dev_warn(&client->dev, "i2c reg write failed %d\n", ret);
  		if (ret >= 0)
  			ret = -EREMOTEIO;
  		return ret;
  	}
  	return 0;
  }
  
  static int rtl2830_probe(struct i2c_client *client,
  			 const struct i2c_device_id *id)
  {
  	struct rtl2830_platform_data *pdata = client->dev.platform_data;
  	struct rtl2830_dev *dev;
  	int ret;
  	u8 u8tmp;
  	static const struct regmap_bus regmap_bus = {
  		.read = rtl2830_regmap_read,
  		.write = rtl2830_regmap_write,
  		.gather_write = rtl2830_regmap_gather_write,
  		.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
  	};
  	static const struct regmap_range_cfg regmap_range_cfg[] = {
  		{
  			.selector_reg     = 0x00,
  			.selector_mask    = 0xff,
  			.selector_shift   = 0,
  			.window_start     = 0,
  			.window_len       = 0x100,
  			.range_min        = 0 * 0x100,
  			.range_max        = 5 * 0x100,
  		},
  	};
  	static const struct regmap_config regmap_config = {
  		.reg_bits    =  8,
  		.val_bits    =  8,
  		.max_register = 5 * 0x100,
  		.ranges = regmap_range_cfg,
  		.num_ranges = ARRAY_SIZE(regmap_range_cfg),
  	};
  
  	dev_dbg(&client->dev, "\n");
  
  	if (pdata == NULL) {
  		ret = -EINVAL;
  		goto err;
  	}
  
  	/* allocate memory for the internal state */
  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  	if (dev == NULL) {
  		ret = -ENOMEM;
  		goto err;
  	}
  
  	/* setup the state */
  	i2c_set_clientdata(client, dev);
  	dev->client = client;
  	dev->pdata = client->dev.platform_data;
  	dev->sleeping = true;
  	INIT_DELAYED_WORK(&dev->stat_work, rtl2830_stat_work);
  	dev->regmap = regmap_init(&client->dev, &regmap_bus, client,
  				  &regmap_config);
  	if (IS_ERR(dev->regmap)) {
  		ret = PTR_ERR(dev->regmap);
  		goto err_kfree;
  	}
  
  	/* check if the demod is there */
  	ret = rtl2830_bulk_read(client, 0x000, &u8tmp, 1);
  	if (ret)
  		goto err_regmap_exit;
  
  	/* create muxed i2c adapter for tuner */
  	dev->muxc = i2c_mux_alloc(client->adapter, &client->dev, 1, 0, 0,
  				  rtl2830_select, NULL);
  	if (!dev->muxc) {
  		ret = -ENOMEM;
  		goto err_regmap_exit;
  	}
  	dev->muxc->priv = client;
  	ret = i2c_mux_add_adapter(dev->muxc, 0, 0, 0);
  	if (ret)
  		goto err_regmap_exit;
  
  	/* create dvb frontend */
  	memcpy(&dev->fe.ops, &rtl2830_ops, sizeof(dev->fe.ops));
  	dev->fe.demodulator_priv = client;
  
  	/* setup callbacks */
  	pdata->get_dvb_frontend = rtl2830_get_dvb_frontend;
  	pdata->get_i2c_adapter = rtl2830_get_i2c_adapter;
  	pdata->pid_filter = rtl2830_pid_filter;
  	pdata->pid_filter_ctrl = rtl2830_pid_filter_ctrl;
  
  	dev_info(&client->dev, "Realtek RTL2830 successfully attached\n");
  
  	return 0;
  err_regmap_exit:
  	regmap_exit(dev->regmap);
  err_kfree:
  	kfree(dev);
  err:
  	dev_dbg(&client->dev, "failed=%d\n", ret);
  	return ret;
  }
  
  static int rtl2830_remove(struct i2c_client *client)
  {
  	struct rtl2830_dev *dev = i2c_get_clientdata(client);
  
  	dev_dbg(&client->dev, "\n");
  
  	/* stop statistics polling */
  	cancel_delayed_work_sync(&dev->stat_work);
  
  	i2c_mux_del_adapters(dev->muxc);
  	regmap_exit(dev->regmap);
  	kfree(dev);
  
  	return 0;
  }
  
  static const struct i2c_device_id rtl2830_id_table[] = {
  	{"rtl2830", 0},
  	{}
  };
  MODULE_DEVICE_TABLE(i2c, rtl2830_id_table);
  
  static struct i2c_driver rtl2830_driver = {
  	.driver = {
  		.name	= "rtl2830",
  	},
  	.probe		= rtl2830_probe,
  	.remove		= rtl2830_remove,
  	.id_table	= rtl2830_id_table,
  };
  
  module_i2c_driver(rtl2830_driver);
  
  MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
  MODULE_DESCRIPTION("Realtek RTL2830 DVB-T demodulator driver");
  MODULE_LICENSE("GPL");
  