drivers/media/dvb-frontends/atbm8830.c - linux/torvalds/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *    Support for AltoBeam GB20600 (a.k.a DMB-TH) demodulator
  *    ATBM8830, ATBM8831
  *
  *    Copyright (C) 2009 David T.L. Wong <davidtlwong@gmail.com>
  */

 #include <asm/div64.h>
 #include <media/dvb_frontend.h>

 #include "atbm8830.h"
 #include "atbm8830_priv.h"

 #define dprintk(args...) \
 	do { \
 		if (debug) \
 			printk(KERN_DEBUG "atbm8830: " args); \
 	} while (0)

 static int debug;

 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

 static int atbm8830_write_reg(struct atbm_state *priv, u16 reg, u8 data)
 {
 	int ret = 0;
 	u8 dev_addr;
 	u8 buf1[] = { reg >> 8, reg & 0xFF };
 	u8 buf2[] = { data };
 	struct i2c_msg msg1 = { .flags = 0, .buf = buf1, .len = 2 };
 	struct i2c_msg msg2 = { .flags = 0, .buf = buf2, .len = 1 };

 	dev_addr = priv->config->demod_address;
 	msg1.addr = dev_addr;
 	msg2.addr = dev_addr;

 	if (debug >= 2)
 		dprintk("%s: reg=0x%04X, data=0x%02X\n", __func__, reg, data);

 	ret = i2c_transfer(priv->i2c, &msg1, 1);
 	if (ret != 1)
 		return -EIO;

 	ret = i2c_transfer(priv->i2c, &msg2, 1);
 	return (ret != 1) ? -EIO : 0;
 }

 static int atbm8830_read_reg(struct atbm_state *priv, u16 reg, u8 *p_data)
 {
 	int ret;
 	u8 dev_addr;

 	u8 buf1[] = { reg >> 8, reg & 0xFF };
 	u8 buf2[] = { 0 };
 	struct i2c_msg msg1 = { .flags = 0, .buf = buf1, .len = 2 };
 	struct i2c_msg msg2 = { .flags = I2C_M_RD, .buf = buf2, .len = 1 };

 	dev_addr = priv->config->demod_address;
 	msg1.addr = dev_addr;
 	msg2.addr = dev_addr;

 	ret = i2c_transfer(priv->i2c, &msg1, 1);
 	if (ret != 1) {
 		dprintk("%s: error reg=0x%04x, ret=%i\n", __func__, reg, ret);
 		return -EIO;
 	}

 	ret = i2c_transfer(priv->i2c, &msg2, 1);
 	if (ret != 1)
 		return -EIO;

 	*p_data = buf2[0];
 	if (debug >= 2)
 		dprintk("%s: reg=0x%04X, data=0x%02X\n",
 			__func__, reg, buf2[0]);

 	return 0;
 }

 /* Lock register latch so that multi-register read is atomic */
 static inline int atbm8830_reglatch_lock(struct atbm_state *priv, int lock)
 {
 	return atbm8830_write_reg(priv, REG_READ_LATCH, lock ? 1 : 0);
 }

 static int set_osc_freq(struct atbm_state *priv, u32 freq /*in kHz*/)
 {
 	u32 val;
 	u64 t;

 	/* 0x100000 * freq / 30.4MHz */
 	t = (u64)0x100000 * freq;
 	do_div(t, 30400);
 	val = t;

 	atbm8830_write_reg(priv, REG_OSC_CLK, val);
 	atbm8830_write_reg(priv, REG_OSC_CLK + 1, val >> 8);
 	atbm8830_write_reg(priv, REG_OSC_CLK + 2, val >> 16);

 	return 0;
 }

 static int set_if_freq(struct atbm_state *priv, u32 freq /*in kHz*/)
 {

 	u32 fs = priv->config->osc_clk_freq;
 	u64 t;
 	u32 val;
 	u8 dat;

 	if (freq != 0) {
 		/* 2 * PI * (freq - fs) / fs * (2 ^ 22) */
 		t = (u64) 2 * 31416 * (freq - fs);
 		t <<= 22;
 		do_div(t, fs);
 		do_div(t, 1000);
 		val = t;

 		atbm8830_write_reg(priv, REG_TUNER_BASEBAND, 1);
 		atbm8830_write_reg(priv, REG_IF_FREQ, val);
 		atbm8830_write_reg(priv, REG_IF_FREQ+1, val >> 8);
 		atbm8830_write_reg(priv, REG_IF_FREQ+2, val >> 16);

 		atbm8830_read_reg(priv, REG_ADC_CONFIG, &dat);
 		dat &= 0xFC;
 		atbm8830_write_reg(priv, REG_ADC_CONFIG, dat);
 	} else {
 		/* Zero IF */
 		atbm8830_write_reg(priv, REG_TUNER_BASEBAND, 0);

 		atbm8830_read_reg(priv, REG_ADC_CONFIG, &dat);
 		dat &= 0xFC;
 		dat |= 0x02;
 		atbm8830_write_reg(priv, REG_ADC_CONFIG, dat);

 		if (priv->config->zif_swap_iq)
 			atbm8830_write_reg(priv, REG_SWAP_I_Q, 0x03);
 		else
 			atbm8830_write_reg(priv, REG_SWAP_I_Q, 0x01);
 	}

 	return 0;
 }

 static int is_locked(struct atbm_state *priv, u8 *locked)
 {
 	u8 status;

 	atbm8830_read_reg(priv, REG_LOCK_STATUS, &status);

 	if (locked != NULL)
 		*locked = (status == 1);
 	return 0;
 }

 static int set_agc_config(struct atbm_state *priv,
 	u8 min, u8 max, u8 hold_loop)
 {
 	/* no effect if both min and max are zero */
 	if (!min && !max)
 	    return 0;

 	atbm8830_write_reg(priv, REG_AGC_MIN, min);
 	atbm8830_write_reg(priv, REG_AGC_MAX, max);
 	atbm8830_write_reg(priv, REG_AGC_HOLD_LOOP, hold_loop);

 	return 0;
 }

 static int set_static_channel_mode(struct atbm_state *priv)
 {
 	int i;

 	for (i = 0; i < 5; i++)
 		atbm8830_write_reg(priv, 0x099B + i, 0x08);

 	atbm8830_write_reg(priv, 0x095B, 0x7F);
 	atbm8830_write_reg(priv, 0x09CB, 0x01);
 	atbm8830_write_reg(priv, 0x09CC, 0x7F);
 	atbm8830_write_reg(priv, 0x09CD, 0x7F);
 	atbm8830_write_reg(priv, 0x0E01, 0x20);

 	/* For single carrier */
 	atbm8830_write_reg(priv, 0x0B03, 0x0A);
 	atbm8830_write_reg(priv, 0x0935, 0x10);
 	atbm8830_write_reg(priv, 0x0936, 0x08);
 	atbm8830_write_reg(priv, 0x093E, 0x08);
 	atbm8830_write_reg(priv, 0x096E, 0x06);

 	/* frame_count_max0 */
 	atbm8830_write_reg(priv, 0x0B09, 0x00);
 	/* frame_count_max1 */
 	atbm8830_write_reg(priv, 0x0B0A, 0x08);

 	return 0;
 }

 static int set_ts_config(struct atbm_state *priv)
 {
 	const struct atbm8830_config *cfg = priv->config;

 	/*Set parallel/serial ts mode*/
 	atbm8830_write_reg(priv, REG_TS_SERIAL, cfg->serial_ts ? 1 : 0);
 	atbm8830_write_reg(priv, REG_TS_CLK_MODE, cfg->serial_ts ? 1 : 0);
 	/*Set ts sampling edge*/
 	atbm8830_write_reg(priv, REG_TS_SAMPLE_EDGE,
 		cfg->ts_sampling_edge ? 1 : 0);
 	/*Set ts clock freerun*/
 	atbm8830_write_reg(priv, REG_TS_CLK_FREERUN,
 		cfg->ts_clk_gated ? 0 : 1);

 	return 0;
 }

 static int atbm8830_init(struct dvb_frontend *fe)
 {
 	struct atbm_state *priv = fe->demodulator_priv;
 	const struct atbm8830_config *cfg = priv->config;

 	/*Set oscillator frequency*/
 	set_osc_freq(priv, cfg->osc_clk_freq);

 	/*Set IF frequency*/
 	set_if_freq(priv, cfg->if_freq);

 	/*Set AGC Config*/
 	set_agc_config(priv, cfg->agc_min, cfg->agc_max,
 		cfg->agc_hold_loop);

 	/*Set static channel mode*/
 	set_static_channel_mode(priv);

 	set_ts_config(priv);
 	/*Turn off DSP reset*/
 	atbm8830_write_reg(priv, 0x000A, 0);

 	/*SW version test*/
 	atbm8830_write_reg(priv, 0x020C, 11);

 	/* Run */
 	atbm8830_write_reg(priv, REG_DEMOD_RUN, 1);

 	return 0;
 }


 static void atbm8830_release(struct dvb_frontend *fe)
 {
 	struct atbm_state *state = fe->demodulator_priv;
 	dprintk("%s\n", __func__);

 	kfree(state);
 }

 static int atbm8830_set_fe(struct dvb_frontend *fe)
 {
 	struct atbm_state *priv = fe->demodulator_priv;
 	int i;
 	u8 locked = 0;
 	dprintk("%s\n", __func__);

 	/* set frequency */
 	if (fe->ops.tuner_ops.set_params) {
 		if (fe->ops.i2c_gate_ctrl)
 			fe->ops.i2c_gate_ctrl(fe, 1);
 		fe->ops.tuner_ops.set_params(fe);
 		if (fe->ops.i2c_gate_ctrl)
 			fe->ops.i2c_gate_ctrl(fe, 0);
 	}

 	/* start auto lock */
 	for (i = 0; i < 10; i++) {
 		mdelay(100);
 		dprintk("Try %d\n", i);
 		is_locked(priv, &locked);
 		if (locked != 0) {
 			dprintk("ATBM8830 locked!\n");
 			break;
 		}
 	}

 	return 0;
 }

 static int atbm8830_get_fe(struct dvb_frontend *fe,
 			   struct dtv_frontend_properties *c)
 {
 	dprintk("%s\n", __func__);

 	/* TODO: get real readings from device */
 	/* inversion status */
 	c->inversion = INVERSION_OFF;

 	/* bandwidth */
 	c->bandwidth_hz = 8000000;

 	c->code_rate_HP = FEC_AUTO;
 	c->code_rate_LP = FEC_AUTO;

 	c->modulation = QAM_AUTO;

 	/* transmission mode */
 	c->transmission_mode = TRANSMISSION_MODE_AUTO;

 	/* guard interval */
 	c->guard_interval = GUARD_INTERVAL_AUTO;

 	/* hierarchy */
 	c->hierarchy = HIERARCHY_NONE;

 	return 0;
 }

 static int atbm8830_get_tune_settings(struct dvb_frontend *fe,
 	struct dvb_frontend_tune_settings *fesettings)
 {
 	fesettings->min_delay_ms = 0;
 	fesettings->step_size = 0;
 	fesettings->max_drift = 0;
 	return 0;
 }

 static int atbm8830_read_status(struct dvb_frontend *fe,
 				enum fe_status *fe_status)
 {
 	struct atbm_state *priv = fe->demodulator_priv;
 	u8 locked = 0;
 	u8 agc_locked = 0;

 	dprintk("%s\n", __func__);
 	*fe_status = 0;

 	is_locked(priv, &locked);
 	if (locked) {
 		*fe_status |= FE_HAS_SIGNAL | FE_HAS_CARRIER |
 			FE_HAS_VITERBI | FE_HAS_SYNC | FE_HAS_LOCK;
 	}
 	dprintk("%s: fe_status=0x%x\n", __func__, *fe_status);

 	atbm8830_read_reg(priv, REG_AGC_LOCK, &agc_locked);
 	dprintk("AGC Lock: %d\n", agc_locked);

 	return 0;
 }

 static int atbm8830_read_ber(struct dvb_frontend *fe, u32 *ber)
 {
 	struct atbm_state *priv = fe->demodulator_priv;
 	u32 frame_err;
 	u8 t;

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

 	atbm8830_reglatch_lock(priv, 1);

 	atbm8830_read_reg(priv, REG_FRAME_ERR_CNT + 1, &t);
 	frame_err = t & 0x7F;
 	frame_err <<= 8;
 	atbm8830_read_reg(priv, REG_FRAME_ERR_CNT, &t);
 	frame_err |= t;

 	atbm8830_reglatch_lock(priv, 0);

 	*ber = frame_err * 100 / 32767;

 	dprintk("%s: ber=0x%x\n", __func__, *ber);
 	return 0;
 }

 static int atbm8830_read_signal_strength(struct dvb_frontend *fe, u16 *signal)
 {
 	struct atbm_state *priv = fe->demodulator_priv;
 	u32 pwm;
 	u8 t;

 	dprintk("%s\n", __func__);
 	atbm8830_reglatch_lock(priv, 1);

 	atbm8830_read_reg(priv, REG_AGC_PWM_VAL + 1, &t);
 	pwm = t & 0x03;
 	pwm <<= 8;
 	atbm8830_read_reg(priv, REG_AGC_PWM_VAL, &t);
 	pwm |= t;

 	atbm8830_reglatch_lock(priv, 0);

 	dprintk("AGC PWM = 0x%02X\n", pwm);
 	pwm = 0x400 - pwm;

 	*signal = pwm * 0x10000 / 0x400;

 	return 0;
 }

 static int atbm8830_read_snr(struct dvb_frontend *fe, u16 *snr)
 {
 	dprintk("%s\n", __func__);
 	*snr = 0;
 	return 0;
 }

 static int atbm8830_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
 {
 	dprintk("%s\n", __func__);
 	*ucblocks = 0;
 	return 0;
 }

 static int atbm8830_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
 {
 	struct atbm_state *priv = fe->demodulator_priv;

 	return atbm8830_write_reg(priv, REG_I2C_GATE, enable ? 1 : 0);
 }

 static const struct dvb_frontend_ops atbm8830_ops = {
 	.delsys = { SYS_DTMB },
 	.info = {
 		.name = "AltoBeam ATBM8830/8831 DMB-TH",
 		.frequency_min_hz = 474 * MHz,
 		.frequency_max_hz = 858 * MHz,
 		.frequency_stepsize_hz = 10 * kHz,
 		.caps =
 			FE_CAN_FEC_AUTO |
 			FE_CAN_QAM_AUTO |
 			FE_CAN_TRANSMISSION_MODE_AUTO |
 			FE_CAN_GUARD_INTERVAL_AUTO
 	},

 	.release = atbm8830_release,

 	.init = atbm8830_init,
 	.sleep = NULL,
 	.write = NULL,
 	.i2c_gate_ctrl = atbm8830_i2c_gate_ctrl,

 	.set_frontend = atbm8830_set_fe,
 	.get_frontend = atbm8830_get_fe,
 	.get_tune_settings = atbm8830_get_tune_settings,

 	.read_status = atbm8830_read_status,
 	.read_ber = atbm8830_read_ber,
 	.read_signal_strength = atbm8830_read_signal_strength,
 	.read_snr = atbm8830_read_snr,
 	.read_ucblocks = atbm8830_read_ucblocks,
 };

 struct dvb_frontend *atbm8830_attach(const struct atbm8830_config *config,
 	struct i2c_adapter *i2c)
 {
 	struct atbm_state *priv = NULL;
 	u8 data = 0;

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

 	if (config == NULL || i2c == NULL)
 		return NULL;

 	priv = kzalloc(sizeof(struct atbm_state), GFP_KERNEL);
 	if (priv == NULL)
 		goto error_out;

 	priv->config = config;
 	priv->i2c = i2c;

 	/* check if the demod is there */
 	if (atbm8830_read_reg(priv, REG_CHIP_ID, &data) != 0) {
 		dprintk("%s atbm8830/8831 not found at i2c addr 0x%02X\n",
 			__func__, priv->config->demod_address);
 		goto error_out;
 	}
 	dprintk("atbm8830 chip id: 0x%02X\n", data);

 	memcpy(&priv->frontend.ops, &atbm8830_ops,
 	       sizeof(struct dvb_frontend_ops));
 	priv->frontend.demodulator_priv = priv;

 	atbm8830_init(&priv->frontend);

 	atbm8830_i2c_gate_ctrl(&priv->frontend, 1);

 	return &priv->frontend;

 error_out:
 	dprintk("%s() error_out\n", __func__);
 	kfree(priv);
 	return NULL;

 }
 EXPORT_SYMBOL(atbm8830_attach);

 MODULE_DESCRIPTION("AltoBeam ATBM8830/8831 GB20600 demodulator driver");
 MODULE_AUTHOR("David T. L. Wong <davidtlwong@gmail.com>");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Support for AltoBeam GB20600 (a.k.a DMB-TH) demodulator
	* ATBM8830, ATBM8831
	*
	* Copyright (C) 2009 David T.L. Wong <davidtlwong@gmail.com>
	*/

	#include <asm/div64.h>
	#include <media/dvb_frontend.h>

	#include "atbm8830.h"
	#include "atbm8830_priv.h"

	#define dprintk(args...) \
	do { \
	if (debug) \
	printk(KERN_DEBUG "atbm8830: " args); \
	} while (0)

	static int debug;

	module_param(debug, int, 0644);
	MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

	static int atbm8830_write_reg(struct atbm_state *priv, u16 reg, u8 data)
	{
	int ret = 0;
	u8 dev_addr;
	u8 buf1[] = { reg >> 8, reg & 0xFF };
	u8 buf2[] = { data };
	struct i2c_msg msg1 = { .flags = 0, .buf = buf1, .len = 2 };
	struct i2c_msg msg2 = { .flags = 0, .buf = buf2, .len = 1 };

	dev_addr = priv->config->demod_address;
	msg1.addr = dev_addr;
	msg2.addr = dev_addr;

	if (debug >= 2)
	dprintk("%s: reg=0x%04X, data=0x%02X\n", __func__, reg, data);

	ret = i2c_transfer(priv->i2c, &msg1, 1);
	if (ret != 1)
	return -EIO;

	ret = i2c_transfer(priv->i2c, &msg2, 1);
	return (ret != 1) ? -EIO : 0;
	}

	static int atbm8830_read_reg(struct atbm_state priv, u16 reg, u8 p_data)
	{
	int ret;
	u8 dev_addr;

	u8 buf1[] = { reg >> 8, reg & 0xFF };
	u8 buf2[] = { 0 };
	struct i2c_msg msg1 = { .flags = 0, .buf = buf1, .len = 2 };
	struct i2c_msg msg2 = { .flags = I2C_M_RD, .buf = buf2, .len = 1 };

	dev_addr = priv->config->demod_address;
	msg1.addr = dev_addr;
	msg2.addr = dev_addr;

	ret = i2c_transfer(priv->i2c, &msg1, 1);
	if (ret != 1) {
	dprintk("%s: error reg=0x%04x, ret=%i\n", __func__, reg, ret);
	return -EIO;
	}

	ret = i2c_transfer(priv->i2c, &msg2, 1);
	if (ret != 1)
	return -EIO;

	*p_data = buf2[0];
	if (debug >= 2)
	dprintk("%s: reg=0x%04X, data=0x%02X\n",
	__func__, reg, buf2[0]);

	return 0;
	}

	/* Lock register latch so that multi-register read is atomic */
	static inline int atbm8830_reglatch_lock(struct atbm_state *priv, int lock)
	{
	return atbm8830_write_reg(priv, REG_READ_LATCH, lock ? 1 : 0);
	}

	static int set_osc_freq(struct atbm_state priv, u32 freq /in kHz*/)
	{
	u32 val;
	u64 t;

	/* 0x100000 * freq / 30.4MHz */
	t = (u64)0x100000 * freq;
	do_div(t, 30400);
	val = t;

	atbm8830_write_reg(priv, REG_OSC_CLK, val);
	atbm8830_write_reg(priv, REG_OSC_CLK + 1, val >> 8);
	atbm8830_write_reg(priv, REG_OSC_CLK + 2, val >> 16);

	return 0;
	}

	static int set_if_freq(struct atbm_state priv, u32 freq /in kHz*/)
	{

	u32 fs = priv->config->osc_clk_freq;
	u64 t;
	u32 val;
	u8 dat;

	if (freq != 0) {
	/* 2 * PI * (freq - fs) / fs * (2 ^ 22) */
	t = (u64) 2 * 31416 * (freq - fs);
	t <<= 22;
	do_div(t, fs);
	do_div(t, 1000);
	val = t;

	atbm8830_write_reg(priv, REG_TUNER_BASEBAND, 1);
	atbm8830_write_reg(priv, REG_IF_FREQ, val);
	atbm8830_write_reg(priv, REG_IF_FREQ+1, val >> 8);
	atbm8830_write_reg(priv, REG_IF_FREQ+2, val >> 16);

	atbm8830_read_reg(priv, REG_ADC_CONFIG, &dat);
	dat &= 0xFC;
	atbm8830_write_reg(priv, REG_ADC_CONFIG, dat);
	} else {
	/* Zero IF */
	atbm8830_write_reg(priv, REG_TUNER_BASEBAND, 0);

	atbm8830_read_reg(priv, REG_ADC_CONFIG, &dat);
	dat &= 0xFC;
	dat \|= 0x02;
	atbm8830_write_reg(priv, REG_ADC_CONFIG, dat);

	if (priv->config->zif_swap_iq)
	atbm8830_write_reg(priv, REG_SWAP_I_Q, 0x03);
	else
	atbm8830_write_reg(priv, REG_SWAP_I_Q, 0x01);
	}

	return 0;
	}

	static int is_locked(struct atbm_state priv, u8 locked)
	{
	u8 status;

	atbm8830_read_reg(priv, REG_LOCK_STATUS, &status);

	if (locked != NULL)
	*locked = (status == 1);
	return 0;
	}

	static int set_agc_config(struct atbm_state *priv,
	u8 min, u8 max, u8 hold_loop)
	{
	/* no effect if both min and max are zero */
	if (!min && !max)
	return 0;

	atbm8830_write_reg(priv, REG_AGC_MIN, min);
	atbm8830_write_reg(priv, REG_AGC_MAX, max);
	atbm8830_write_reg(priv, REG_AGC_HOLD_LOOP, hold_loop);

	return 0;
	}

	static int set_static_channel_mode(struct atbm_state *priv)
	{
	int i;

	for (i = 0; i < 5; i++)
	atbm8830_write_reg(priv, 0x099B + i, 0x08);

	atbm8830_write_reg(priv, 0x095B, 0x7F);
	atbm8830_write_reg(priv, 0x09CB, 0x01);
	atbm8830_write_reg(priv, 0x09CC, 0x7F);
	atbm8830_write_reg(priv, 0x09CD, 0x7F);
	atbm8830_write_reg(priv, 0x0E01, 0x20);

	/* For single carrier */
	atbm8830_write_reg(priv, 0x0B03, 0x0A);
	atbm8830_write_reg(priv, 0x0935, 0x10);
	atbm8830_write_reg(priv, 0x0936, 0x08);
	atbm8830_write_reg(priv, 0x093E, 0x08);
	atbm8830_write_reg(priv, 0x096E, 0x06);

	/* frame_count_max0 */
	atbm8830_write_reg(priv, 0x0B09, 0x00);
	/* frame_count_max1 */
	atbm8830_write_reg(priv, 0x0B0A, 0x08);

	return 0;
	}

	static int set_ts_config(struct atbm_state *priv)
	{
	const struct atbm8830_config *cfg = priv->config;

	/Set parallel/serial ts mode/
	atbm8830_write_reg(priv, REG_TS_SERIAL, cfg->serial_ts ? 1 : 0);
	atbm8830_write_reg(priv, REG_TS_CLK_MODE, cfg->serial_ts ? 1 : 0);
	/Set ts sampling edge/
	atbm8830_write_reg(priv, REG_TS_SAMPLE_EDGE,
	cfg->ts_sampling_edge ? 1 : 0);
	/Set ts clock freerun/
	atbm8830_write_reg(priv, REG_TS_CLK_FREERUN,
	cfg->ts_clk_gated ? 0 : 1);

	return 0;
	}

	static int atbm8830_init(struct dvb_frontend *fe)
	{
	struct atbm_state *priv = fe->demodulator_priv;
	const struct atbm8830_config *cfg = priv->config;

	/Set oscillator frequency/
	set_osc_freq(priv, cfg->osc_clk_freq);

	/Set IF frequency/
	set_if_freq(priv, cfg->if_freq);

	/Set AGC Config/
	set_agc_config(priv, cfg->agc_min, cfg->agc_max,
	cfg->agc_hold_loop);

	/Set static channel mode/
	set_static_channel_mode(priv);

	set_ts_config(priv);
	/Turn off DSP reset/
	atbm8830_write_reg(priv, 0x000A, 0);

	/SW version test/
	atbm8830_write_reg(priv, 0x020C, 11);

	/* Run */
	atbm8830_write_reg(priv, REG_DEMOD_RUN, 1);

	return 0;
	}


	static void atbm8830_release(struct dvb_frontend *fe)
	{
	struct atbm_state *state = fe->demodulator_priv;
	dprintk("%s\n", __func__);

	kfree(state);
	}

	static int atbm8830_set_fe(struct dvb_frontend *fe)
	{
	struct atbm_state *priv = fe->demodulator_priv;
	int i;
	u8 locked = 0;
	dprintk("%s\n", __func__);

	/* set frequency */
	if (fe->ops.tuner_ops.set_params) {
	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 1);
	fe->ops.tuner_ops.set_params(fe);
	if (fe->ops.i2c_gate_ctrl)
	fe->ops.i2c_gate_ctrl(fe, 0);
	}

	/* start auto lock */
	for (i = 0; i < 10; i++) {
	mdelay(100);
	dprintk("Try %d\n", i);
	is_locked(priv, &locked);
	if (locked != 0) {
	dprintk("ATBM8830 locked!\n");
	break;
	}
	}

	return 0;
	}

	static int atbm8830_get_fe(struct dvb_frontend *fe,
	struct dtv_frontend_properties *c)
	{
	dprintk("%s\n", __func__);

	/* TODO: get real readings from device */
	/* inversion status */
	c->inversion = INVERSION_OFF;

	/* bandwidth */
	c->bandwidth_hz = 8000000;

	c->code_rate_HP = FEC_AUTO;
	c->code_rate_LP = FEC_AUTO;

	c->modulation = QAM_AUTO;

	/* transmission mode */
	c->transmission_mode = TRANSMISSION_MODE_AUTO;

	/* guard interval */
	c->guard_interval = GUARD_INTERVAL_AUTO;

	/* hierarchy */
	c->hierarchy = HIERARCHY_NONE;

	return 0;
	}

	static int atbm8830_get_tune_settings(struct dvb_frontend *fe,
	struct dvb_frontend_tune_settings *fesettings)
	{
	fesettings->min_delay_ms = 0;
	fesettings->step_size = 0;
	fesettings->max_drift = 0;
	return 0;
	}

	static int atbm8830_read_status(struct dvb_frontend *fe,
	enum fe_status *fe_status)
	{
	struct atbm_state *priv = fe->demodulator_priv;
	u8 locked = 0;
	u8 agc_locked = 0;

	dprintk("%s\n", __func__);
	*fe_status = 0;

	is_locked(priv, &locked);
	if (locked) {
	*fe_status \|= FE_HAS_SIGNAL \| FE_HAS_CARRIER \|
	FE_HAS_VITERBI \| FE_HAS_SYNC \| FE_HAS_LOCK;
	}
	dprintk("%s: fe_status=0x%x\n", __func__, *fe_status);

	atbm8830_read_reg(priv, REG_AGC_LOCK, &agc_locked);
	dprintk("AGC Lock: %d\n", agc_locked);

	return 0;
	}

	static int atbm8830_read_ber(struct dvb_frontend fe, u32 ber)
	{
	struct atbm_state *priv = fe->demodulator_priv;
	u32 frame_err;
	u8 t;

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

	atbm8830_reglatch_lock(priv, 1);

	atbm8830_read_reg(priv, REG_FRAME_ERR_CNT + 1, &t);
	frame_err = t & 0x7F;
	frame_err <<= 8;
	atbm8830_read_reg(priv, REG_FRAME_ERR_CNT, &t);
	frame_err \|= t;

	atbm8830_reglatch_lock(priv, 0);

	ber = frame_err 100 / 32767;

	dprintk("%s: ber=0x%x\n", __func__, *ber);
	return 0;
	}

	static int atbm8830_read_signal_strength(struct dvb_frontend fe, u16 signal)
	{
	struct atbm_state *priv = fe->demodulator_priv;
	u32 pwm;
	u8 t;

	dprintk("%s\n", __func__);
	atbm8830_reglatch_lock(priv, 1);

	atbm8830_read_reg(priv, REG_AGC_PWM_VAL + 1, &t);
	pwm = t & 0x03;
	pwm <<= 8;
	atbm8830_read_reg(priv, REG_AGC_PWM_VAL, &t);
	pwm \|= t;

	atbm8830_reglatch_lock(priv, 0);

	dprintk("AGC PWM = 0x%02X\n", pwm);
	pwm = 0x400 - pwm;

	signal = pwm 0x10000 / 0x400;

	return 0;
	}

	static int atbm8830_read_snr(struct dvb_frontend fe, u16 snr)
	{
	dprintk("%s\n", __func__);
	*snr = 0;
	return 0;
	}

	static int atbm8830_read_ucblocks(struct dvb_frontend fe, u32 ucblocks)
	{
	dprintk("%s\n", __func__);
	*ucblocks = 0;
	return 0;
	}

	static int atbm8830_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
	{
	struct atbm_state *priv = fe->demodulator_priv;

	return atbm8830_write_reg(priv, REG_I2C_GATE, enable ? 1 : 0);
	}

	static const struct dvb_frontend_ops atbm8830_ops = {
	.delsys = { SYS_DTMB },
	.info = {
	.name = "AltoBeam ATBM8830/8831 DMB-TH",
	.frequency_min_hz = 474 * MHz,
	.frequency_max_hz = 858 * MHz,
	.frequency_stepsize_hz = 10 * kHz,
	.caps =
	FE_CAN_FEC_AUTO \|
	FE_CAN_QAM_AUTO \|
	FE_CAN_TRANSMISSION_MODE_AUTO \|
	FE_CAN_GUARD_INTERVAL_AUTO
	},

	.release = atbm8830_release,

	.init = atbm8830_init,
	.sleep = NULL,
	.write = NULL,
	.i2c_gate_ctrl = atbm8830_i2c_gate_ctrl,

	.set_frontend = atbm8830_set_fe,
	.get_frontend = atbm8830_get_fe,
	.get_tune_settings = atbm8830_get_tune_settings,

	.read_status = atbm8830_read_status,
	.read_ber = atbm8830_read_ber,
	.read_signal_strength = atbm8830_read_signal_strength,
	.read_snr = atbm8830_read_snr,
	.read_ucblocks = atbm8830_read_ucblocks,
	};

	struct dvb_frontend atbm8830_attach(const struct atbm8830_config config,
	struct i2c_adapter *i2c)
	{
	struct atbm_state *priv = NULL;
	u8 data = 0;

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

	if (config == NULL \|\| i2c == NULL)
	return NULL;

	priv = kzalloc(sizeof(struct atbm_state), GFP_KERNEL);
	if (priv == NULL)
	goto error_out;

	priv->config = config;
	priv->i2c = i2c;

	/* check if the demod is there */
	if (atbm8830_read_reg(priv, REG_CHIP_ID, &data) != 0) {
	dprintk("%s atbm8830/8831 not found at i2c addr 0x%02X\n",
	__func__, priv->config->demod_address);
	goto error_out;
	}
	dprintk("atbm8830 chip id: 0x%02X\n", data);

	memcpy(&priv->frontend.ops, &atbm8830_ops,
	sizeof(struct dvb_frontend_ops));
	priv->frontend.demodulator_priv = priv;

	atbm8830_init(&priv->frontend);

	atbm8830_i2c_gate_ctrl(&priv->frontend, 1);

	return &priv->frontend;

	error_out:
	dprintk("%s() error_out\n", __func__);
	kfree(priv);
	return NULL;

	}
	EXPORT_SYMBOL(atbm8830_attach);

	MODULE_DESCRIPTION("AltoBeam ATBM8830/8831 GB20600 demodulator driver");
	MODULE_AUTHOR("David T. L. Wong <davidtlwong@gmail.com>");
	MODULE_LICENSE("GPL");