[media] tc90522: add driver for Toshiba TC90522 quad demodulator

This patch adds driver for tc90522 demodulator chips.
The chip contains 4 demod modules that run in parallel and are independently
controllable via separate I2C addresses.
Two of the modules are for ISDB-T and the rest for ISDB-S.
It is used in earthsoft pt3 cards.

Note that this driver does not init the chip,
because the initilization sequence / register setting is not disclosed.
Thus, the driver assumes that the chips are initilized externally
by its parent board driver before fe->ops->init() are called.
Earthsoft PT3 PCIe card, for example, contains the init sequence
in its private memory and provides a command to trigger the sequence.

Signed-off-by: Akihiro Tsukada <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/dvb-frontends/Kconfig

···
 	  A driver for Fujitsu mb86a20s ISDB-T/ISDB-Tsb demodulator.
 	  Say Y when you want to support this frontend.
 
+config DVB_TC90522
+	tristate "Toshiba TC90522"
+	depends on DVB_CORE && I2C
+	default m if !MEDIA_SUBDRV_AUTOSELECT
+	help
+	  A Toshiba TC90522 2xISDB-T + 2xISDB-S demodulator.
+	  Say Y when you want to support this frontend.
+
 comment "Digital terrestrial only tuners/PLL"
 	depends on DVB_CORE
 

drivers/media/dvb-frontends/Makefile

···
 obj-$(CONFIG_DVB_M88RS2000) += m88rs2000.o
 obj-$(CONFIG_DVB_AF9033) += af9033.o
 obj-$(CONFIG_DVB_AS102_FE) += as102_fe.o
+obj-$(CONFIG_DVB_TC90522) += tc90522.o

drivers/media/dvb-frontends/tc90522.c

···
+/*
+ * Toshiba TC90522 Demodulator
+ *
+ * Copyright (C) 2014 Akihiro Tsukada <[e-mail]>
+ *
+ * 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 version 2.
+ *
+ *
+ * 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.
+ */
+
+/*
+ * NOTICE:
+ * This driver is incomplete and lacks init/config of the chips,
+ * as the necessary info is not disclosed.
+ * It assumes that users of this driver (such as a PCI bridge of
+ * DTV receiver cards) properly init and configure the chip
+ * via I2C *before* calling this driver's init() function.
+ *
+ * Currently, PT3 driver is the only one that uses this driver,
+ * and contains init/config code in its firmware.
+ * Thus some part of the code might be dependent on PT3 specific config.
+ */
+
+#include <linux/kernel.h>
+#include <linux/dvb/frontend.h>
+#include "dvb_math.h"
+#include "tc90522.h"
+
+#define TC90522_I2C_THRU_REG 0xfe
+
+#define TC90522_MODULE_IDX(addr) (((u8)(addr) & 0x02U) >> 1)
+
+struct tc90522_state {
+	struct tc90522_config cfg;
+	struct dvb_frontend fe;
+	struct i2c_client *i2c_client;
+	struct i2c_adapter tuner_i2c;
+
+	bool lna;
+};
+
+struct reg_val {
+	u8 reg;
+	u8 val;
+};
+
+static int
+reg_write(struct tc90522_state *state, const struct reg_val *regs, int num)
+{
+	int i, ret;
+	struct i2c_msg msg;
+
+	ret = 0;
+	msg.addr = state->i2c_client->addr;
+	msg.flags = 0;
+	msg.len = 2;
+	for (i = 0; i < num; i++) {
+		msg.buf = (u8 *)&regs[i];
+		ret = i2c_transfer(state->i2c_client->adapter, &msg, 1);
+		if (ret == 0)
+			ret = -EIO;
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+static int reg_read(struct tc90522_state *state, u8 reg, u8 *val, u8 len)
+{
+	struct i2c_msg msgs[2] = {
+		{
+			.addr = state->i2c_client->addr,
+			.flags = 0,
+			.buf = &reg,
+			.len = 1,
+		},
+		{
+			.addr = state->i2c_client->addr,
+			.flags = I2C_M_RD,
+			.buf = val,
+			.len = len,
+		},
+	};
+	int ret;
+
+	ret = i2c_transfer(state->i2c_client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret == ARRAY_SIZE(msgs))
+		ret = 0;
+	else if (ret >= 0)
+		ret = -EIO;
+	return ret;
+}
+
+static struct tc90522_state *cfg_to_state(struct tc90522_config *c)
+{
+	return container_of(c, struct tc90522_state, cfg);
+}
+
+
+static int tc90522s_set_tsid(struct dvb_frontend *fe)
+{
+	struct reg_val set_tsid[] = {
+		{ 0x8f, 00 },
+		{ 0x90, 00 }
+	};
+
+	set_tsid[0].val = (fe->dtv_property_cache.stream_id & 0xff00) >> 8;
+	set_tsid[1].val = fe->dtv_property_cache.stream_id & 0xff;
+	return reg_write(fe->demodulator_priv, set_tsid, ARRAY_SIZE(set_tsid));
+}
+
+static int tc90522t_set_layers(struct dvb_frontend *fe)
+{
+	struct reg_val rv;
+	u8 laysel;
+
+	laysel = ~fe->dtv_property_cache.isdbt_layer_enabled & 0x07;
+	laysel = (laysel & 0x01) << 2 | (laysel & 0x02) | (laysel & 0x04) >> 2;
+	rv.reg = 0x71;
+	rv.val = laysel;
+	return reg_write(fe->demodulator_priv, &rv, 1);
+}
+
+/* frontend ops */
+
+static int tc90522s_read_status(struct dvb_frontend *fe, fe_status_t *status)
+{
+	struct tc90522_state *state;
+	int ret;
+	u8 reg;
+
+	state = fe->demodulator_priv;
+	ret = reg_read(state, 0xc3, &reg, 1);
+	if (ret < 0)
+		return ret;
+
+	*status = 0;
+	if (reg & 0x80) /* input level under min ? */
+		return 0;
+	*status |= FE_HAS_SIGNAL;
+
+	if (reg & 0x60) /* carrier? */
+		return 0;
+	*status |= FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC;
+
+	if (reg & 0x10)
+		return 0;
+	if (reg_read(state, 0xc5, &reg, 1) < 0 || !(reg & 0x03))
+		return 0;
+	*status |= FE_HAS_LOCK;
+	return 0;
+}
+
+static int tc90522t_read_status(struct dvb_frontend *fe, fe_status_t *status)
+{
+	struct tc90522_state *state;
+	int ret;
+	u8 reg;
+
+	state = fe->demodulator_priv;
+	ret = reg_read(state, 0x96, &reg, 1);
+	if (ret < 0)
+		return ret;
+
+	*status = 0;
+	if (reg & 0xe0) {
+		*status = FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI
+				| FE_HAS_SYNC | FE_HAS_LOCK;
+		return 0;
+	}
+
+	ret = reg_read(state, 0x80, &reg, 1);
+	if (ret < 0)
+		return ret;
+
+	if (reg & 0xf0)
+		return 0;
+	*status |= FE_HAS_SIGNAL | FE_HAS_CARRIER;
+
+	if (reg & 0x0c)
+		return 0;
+	*status |= FE_HAS_SYNC | FE_HAS_VITERBI;
+
+	if (reg & 0x02)
+		return 0;
+	*status |= FE_HAS_LOCK;
+	return 0;
+}
+
+static const fe_code_rate_t fec_conv_sat[] = {
+	FEC_NONE, /* unused */
+	FEC_1_2, /* for BPSK */
+	FEC_1_2, FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8, /* for QPSK */
+	FEC_2_3, /* for 8PSK. (trellis code) */
+};
+
+static int tc90522s_get_frontend(struct dvb_frontend *fe)
+{
+	struct tc90522_state *state;
+	struct dtv_frontend_properties *c;
+	struct dtv_fe_stats *stats;
+	int ret, i;
+	int layers;
+	u8 val[10];
+	u32 cndat;
+
+	state = fe->demodulator_priv;
+	c = &fe->dtv_property_cache;
+	c->delivery_system = SYS_ISDBS;
+
+	layers = 0;
+	ret = reg_read(state, 0xe8, val, 3);
+	if (ret == 0) {
+		int slots;
+		u8 v;
+
+		/* high/single layer */
+		v = (val[0] & 0x70) >> 4;
+		c->modulation = (v == 7) ? PSK_8 : QPSK;
+		c->fec_inner = fec_conv_sat[v];
+		c->layer[0].fec = c->fec_inner;
+		c->layer[0].modulation = c->modulation;
+		c->layer[0].segment_count = val[1] & 0x3f; /* slots */
+
+		/* low layer */
+		v = (val[0] & 0x07);
+		c->layer[1].fec = fec_conv_sat[v];
+		if (v == 0)  /* no low layer */
+			c->layer[1].segment_count = 0;
+		else
+			c->layer[1].segment_count = val[2] & 0x3f; /* slots */
+		/* actually, BPSK if v==1, but not defined in fe_modulation_t */
+		c->layer[1].modulation = QPSK;
+		layers = (v > 0) ? 2 : 1;
+
+		slots =  c->layer[0].segment_count +  c->layer[1].segment_count;
+		c->symbol_rate = 28860000 * slots / 48;
+	}
+
+	/* statistics */
+
+	stats = &c->strength;
+	stats->len = 0;
+	/* let the connected tuner set RSSI property cache */
+	if (fe->ops.tuner_ops.get_rf_strength) {
+		u16 dummy;
+
+		fe->ops.tuner_ops.get_rf_strength(fe, &dummy);
+	}
+
+	stats = &c->cnr;
+	stats->len = 1;
+	stats->stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+	cndat = 0;
+	ret = reg_read(state, 0xbc, val, 2);
+	if (ret == 0)
+		cndat = val[0] << 8 | val[1];
+	if (cndat >= 3000) {
+		u32 p, p4;
+		s64 cn;
+
+		cndat -= 3000;  /* cndat: 4.12 fixed point float */
+		/*
+		 * cnr[mdB] = -1634.6 * P^5 + 14341 * P^4 - 50259 * P^3
+		 *                 + 88977 * P^2 - 89565 * P + 58857
+		 *  (P = sqrt(cndat) / 64)
+		 */
+		/* p := sqrt(cndat) << 8 = P << 14, 2.14 fixed  point float */
+		/* cn = cnr << 3 */
+		p = int_sqrt(cndat << 16);
+		p4 = cndat * cndat;
+		cn = (-16346LL * p4 * p / 10) >> 35;
+		cn += (14341LL * p4) >> 21;
+		cn -= (50259LL * cndat * p) >> 23;
+		cn += (88977LL * cndat) >> 9;
+		cn -= (89565LL * p) >> 11;
+		cn += 58857  << 3;
+		stats->stat[0].svalue = cn >> 3;
+		stats->stat[0].scale = FE_SCALE_DECIBEL;
+	}
+
+	/* per-layer post viterbi BER (or PER? config dependent?) */
+	stats = &c->post_bit_error;
+	memset(stats, 0, sizeof(*stats));
+	stats->len = layers;
+	ret = reg_read(state, 0xeb, val, 10);
+	if (ret < 0)
+		for (i = 0; i < layers; i++)
+			stats->stat[i].scale = FE_SCALE_NOT_AVAILABLE;
+	else {
+		for (i = 0; i < layers; i++) {
+			stats->stat[i].scale = FE_SCALE_COUNTER;
+			stats->stat[i].uvalue = val[i * 5] << 16
+				| val[i * 5 + 1] << 8 | val[i * 5 + 2];
+		}
+	}
+	stats = &c->post_bit_count;
+	memset(stats, 0, sizeof(*stats));
+	stats->len = layers;
+	if (ret < 0)
+		for (i = 0; i < layers; i++)
+			stats->stat[i].scale = FE_SCALE_NOT_AVAILABLE;
+	else {
+		for (i = 0; i < layers; i++) {
+			stats->stat[i].scale = FE_SCALE_COUNTER;
+			stats->stat[i].uvalue =
+				val[i * 5 + 3] << 8 | val[i * 5 + 4];
+			stats->stat[i].uvalue *= 204 * 8;
+		}
+	}
+
+	return 0;
+}
+
+
+static const fe_transmit_mode_t tm_conv[] = {
+	TRANSMISSION_MODE_2K,
+	TRANSMISSION_MODE_4K,
+	TRANSMISSION_MODE_8K,
+	0
+};
+
+static const fe_code_rate_t fec_conv_ter[] = {
+	FEC_1_2, FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8, 0, 0, 0
+};
+
+static const fe_modulation_t mod_conv[] = {
+	DQPSK, QPSK, QAM_16, QAM_64, 0, 0, 0, 0
+};
+
+static int tc90522t_get_frontend(struct dvb_frontend *fe)
+{
+	struct tc90522_state *state;
+	struct dtv_frontend_properties *c;
+	struct dtv_fe_stats *stats;
+	int ret, i;
+	int layers;
+	u8 val[15], mode;
+	u32 cndat;
+
+	state = fe->demodulator_priv;
+	c = &fe->dtv_property_cache;
+	c->delivery_system = SYS_ISDBT;
+	c->bandwidth_hz = 6000000;
+	mode = 1;
+	ret = reg_read(state, 0xb0, val, 1);
+	if (ret == 0) {
+		mode = (val[0] & 0xc0) >> 2;
+		c->transmission_mode = tm_conv[mode];
+		c->guard_interval = (val[0] & 0x30) >> 4;
+	}
+
+	ret = reg_read(state, 0xb2, val, 6);
+	layers = 0;
+	if (ret == 0) {
+		u8 v;
+
+		c->isdbt_partial_reception = val[0] & 0x01;
+		c->isdbt_sb_mode = (val[0] & 0xc0) == 0x01;
+
+		/* layer A */
+		v = (val[2] & 0x78) >> 3;
+		if (v == 0x0f)
+			c->layer[0].segment_count = 0;
+		else {
+			layers++;
+			c->layer[0].segment_count = v;
+			c->layer[0].fec = fec_conv_ter[(val[1] & 0x1c) >> 2];
+			c->layer[0].modulation = mod_conv[(val[1] & 0xe0) >> 5];
+			v = (val[1] & 0x03) << 1 | (val[2] & 0x80) >> 7;
+			c->layer[0].interleaving = v;
+		}
+
+		/* layer B */
+		v = (val[3] & 0x03) << 1 | (val[4] & 0xc0) >> 6;
+		if (v == 0x0f)
+			c->layer[1].segment_count = 0;
+		else {
+			layers++;
+			c->layer[1].segment_count = v;
+			c->layer[1].fec = fec_conv_ter[(val[3] & 0xe0) >> 5];
+			c->layer[1].modulation = mod_conv[(val[2] & 0x07)];
+			c->layer[1].interleaving = (val[3] & 0x1c) >> 2;
+		}
+
+		/* layer C */
+		v = (val[5] & 0x1e) >> 1;
+		if (v == 0x0f)
+			c->layer[2].segment_count = 0;
+		else {
+			layers++;
+			c->layer[2].segment_count = v;
+			c->layer[2].fec = fec_conv_ter[(val[4] & 0x07)];
+			c->layer[2].modulation = mod_conv[(val[4] & 0x38) >> 3];
+			c->layer[2].interleaving = (val[5] & 0xe0) >> 5;
+		}
+	}
+
+	/* statistics */
+
+	stats = &c->strength;
+	stats->len = 0;
+	/* let the connected tuner set RSSI property cache */
+	if (fe->ops.tuner_ops.get_rf_strength) {
+		u16 dummy;
+
+		fe->ops.tuner_ops.get_rf_strength(fe, &dummy);
+	}
+
+	stats = &c->cnr;
+	stats->len = 1;
+	stats->stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+	cndat = 0;
+	ret = reg_read(state, 0x8b, val, 3);
+	if (ret == 0)
+		cndat = val[0] << 16 | val[1] << 8 | val[2];
+	if (cndat != 0) {
+		u32 p, tmp;
+		s64 cn;
+
+		/*
+		 * cnr[mdB] = 0.024 P^4 - 1.6 P^3 + 39.8 P^2 + 549.1 P + 3096.5
+		 * (P = 10log10(5505024/cndat))
+		 */
+		/* cn = cnr << 3 (61.3 fixed point float */
+		/* p = 10log10(5505024/cndat) << 24  (8.24 fixed point float)*/
+		p = intlog10(5505024) - intlog10(cndat);
+		p *= 10;
+
+		cn = 24772;
+		cn += ((43827LL * p) / 10) >> 24;
+		tmp = p >> 8;
+		cn += ((3184LL * tmp * tmp) / 10) >> 32;
+		tmp = p >> 13;
+		cn -= ((128LL * tmp * tmp * tmp) / 10) >> 33;
+		tmp = p >> 18;
+		cn += ((192LL * tmp * tmp * tmp * tmp) / 1000) >> 24;
+
+		stats->stat[0].svalue = cn >> 3;
+		stats->stat[0].scale = FE_SCALE_DECIBEL;
+	}
+
+	/* per-layer post viterbi BER (or PER? config dependent?) */
+	stats = &c->post_bit_error;
+	memset(stats, 0, sizeof(*stats));
+	stats->len = layers;
+	ret = reg_read(state, 0x9d, val, 15);
+	if (ret < 0)
+		for (i = 0; i < layers; i++)
+			stats->stat[i].scale = FE_SCALE_NOT_AVAILABLE;
+	else {
+		for (i = 0; i < layers; i++) {
+			stats->stat[i].scale = FE_SCALE_COUNTER;
+			stats->stat[i].uvalue = val[i * 3] << 16
+				| val[i * 3 + 1] << 8 | val[i * 3 + 2];
+		}
+	}
+	stats = &c->post_bit_count;
+	memset(stats, 0, sizeof(*stats));
+	stats->len = layers;
+	if (ret < 0)
+		for (i = 0; i < layers; i++)
+			stats->stat[i].scale = FE_SCALE_NOT_AVAILABLE;
+	else {
+		for (i = 0; i < layers; i++) {
+			stats->stat[i].scale = FE_SCALE_COUNTER;
+			stats->stat[i].uvalue =
+				val[9 + i * 2] << 8 | val[9 + i * 2 + 1];
+			stats->stat[i].uvalue *= 204 * 8;
+		}
+	}
+
+	return 0;
+}
+
+static const struct reg_val reset_sat = { 0x03, 0x01 };
+static const struct reg_val reset_ter = { 0x01, 0x40 };
+
+static int tc90522_set_frontend(struct dvb_frontend *fe)
+{
+	struct tc90522_state *state;
+	int ret;
+
+	state = fe->demodulator_priv;
+
+	if (fe->ops.tuner_ops.set_params)
+		ret = fe->ops.tuner_ops.set_params(fe);
+	else
+		ret = -ENODEV;
+	if (ret < 0)
+		goto failed;
+
+	if (fe->ops.delsys[0] == SYS_ISDBS) {
+		ret = tc90522s_set_tsid(fe);
+		if (ret < 0)
+			goto failed;
+		ret = reg_write(state, &reset_sat, 1);
+	} else {
+		ret = tc90522t_set_layers(fe);
+		if (ret < 0)
+			goto failed;
+		ret = reg_write(state, &reset_ter, 1);
+	}
+	if (ret < 0)
+		goto failed;
+
+	return 0;
+
+failed:
+	dev_warn(&state->tuner_i2c.dev, "(%s) failed. [adap%d-fe%d]\n",
+			__func__, fe->dvb->num, fe->id);
+	return ret;
+}
+
+static int tc90522_get_tune_settings(struct dvb_frontend *fe,
+	struct dvb_frontend_tune_settings *settings)
+{
+	if (fe->ops.delsys[0] == SYS_ISDBS) {
+		settings->min_delay_ms = 250;
+		settings->step_size = 1000;
+		settings->max_drift = settings->step_size * 2;
+	} else {
+		settings->min_delay_ms = 400;
+		settings->step_size = 142857;
+		settings->max_drift = settings->step_size;
+	}
+	return 0;
+}
+
+static int tc90522_set_if_agc(struct dvb_frontend *fe, bool on)
+{
+	struct reg_val agc_sat[] = {
+		{ 0x0a, 0x00 },
+		{ 0x10, 0x30 },
+		{ 0x11, 0x00 },
+		{ 0x03, 0x01 },
+	};
+	struct reg_val agc_ter[] = {
+		{ 0x25, 0x00 },
+		{ 0x23, 0x4c },
+		{ 0x01, 0x40 },
+	};
+	struct tc90522_state *state;
+	struct reg_val *rv;
+	int num;
+
+	state = fe->demodulator_priv;
+	if (fe->ops.delsys[0] == SYS_ISDBS) {
+		agc_sat[0].val = on ? 0xff : 0x00;
+		agc_sat[1].val |= 0x80;
+		agc_sat[1].val |= on ? 0x01 : 0x00;
+		agc_sat[2].val |= on ? 0x40 : 0x00;
+		rv = agc_sat;
+		num = ARRAY_SIZE(agc_sat);
+	} else {
+		agc_ter[0].val = on ? 0x40 : 0x00;
+		agc_ter[1].val |= on ? 0x00 : 0x01;
+		rv = agc_ter;
+		num = ARRAY_SIZE(agc_ter);
+	}
+	return reg_write(state, rv, num);
+}
+
+static const struct reg_val sleep_sat = { 0x17, 0x01 };
+static const struct reg_val sleep_ter = { 0x03, 0x90 };
+
+static int tc90522_sleep(struct dvb_frontend *fe)
+{
+	struct tc90522_state *state;
+	int ret;
+
+	state = fe->demodulator_priv;
+	if (fe->ops.delsys[0] == SYS_ISDBS)
+		ret = reg_write(state, &sleep_sat, 1);
+	else {
+		ret = reg_write(state, &sleep_ter, 1);
+		if (ret == 0 && fe->ops.set_lna &&
+		    fe->dtv_property_cache.lna == LNA_AUTO) {
+			fe->dtv_property_cache.lna = 0;
+			ret = fe->ops.set_lna(fe);
+			fe->dtv_property_cache.lna = LNA_AUTO;
+		}
+	}
+	if (ret < 0)
+		dev_warn(&state->tuner_i2c.dev,
+			"(%s) failed. [adap%d-fe%d]\n",
+			__func__, fe->dvb->num, fe->id);
+	return ret;
+}
+
+static const struct reg_val wakeup_sat = { 0x17, 0x00 };
+static const struct reg_val wakeup_ter = { 0x03, 0x80 };
+
+static int tc90522_init(struct dvb_frontend *fe)
+{
+	struct tc90522_state *state;
+	int ret;
+
+	/*
+	 * Because the init sequence is not public,
+	 * the parent device/driver should have init'ed the device before.
+	 * just wake up the device here.
+	 */
+
+	state = fe->demodulator_priv;
+	if (fe->ops.delsys[0] == SYS_ISDBS)
+		ret = reg_write(state, &wakeup_sat, 1);
+	else {
+		ret = reg_write(state, &wakeup_ter, 1);
+		if (ret == 0 && fe->ops.set_lna &&
+		    fe->dtv_property_cache.lna == LNA_AUTO) {
+			fe->dtv_property_cache.lna = 1;
+			ret = fe->ops.set_lna(fe);
+			fe->dtv_property_cache.lna = LNA_AUTO;
+		}
+	}
+	if (ret < 0) {
+		dev_warn(&state->tuner_i2c.dev,
+			"(%s) failed. [adap%d-fe%d]\n",
+			__func__, fe->dvb->num, fe->id);
+		return ret;
+	}
+
+	/* prefer 'all-layers' to 'none' as a default */
+	if (fe->dtv_property_cache.isdbt_layer_enabled == 0)
+		fe->dtv_property_cache.isdbt_layer_enabled = 7;
+	return tc90522_set_if_agc(fe, true);
+}
+
+
+/*
+ * tuner I2C adapter functions
+ */
+
+static int
+tc90522_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct tc90522_state *state;
+	struct i2c_msg *new_msgs;
+	int i, j;
+	int ret, rd_num;
+	u8 wbuf[256];
+	u8 *p, *bufend;
+
+	if (num <= 0)
+		return -EINVAL;
+
+	rd_num = 0;
+	for (i = 0; i < num; i++)
+		if (msgs[i].flags & I2C_M_RD)
+			rd_num++;
+	new_msgs = kmalloc(sizeof(*new_msgs) * (num + rd_num), GFP_KERNEL);
+	if (!new_msgs)
+		return -ENOMEM;
+
+	state = i2c_get_adapdata(adap);
+	p = wbuf;
+	bufend = wbuf + sizeof(wbuf);
+	for (i = 0, j = 0; i < num; i++, j++) {
+		new_msgs[j].addr = state->i2c_client->addr;
+		new_msgs[j].flags = msgs[i].flags;
+
+		if (msgs[i].flags & I2C_M_RD) {
+			new_msgs[j].flags &= ~I2C_M_RD;
+			if (p + 2 > bufend)
+				break;
+			p[0] = TC90522_I2C_THRU_REG;
+			p[1] = msgs[i].addr << 1 | 0x01;
+			new_msgs[j].buf = p;
+			new_msgs[j].len = 2;
+			p += 2;
+			j++;
+			new_msgs[j].addr = state->i2c_client->addr;
+			new_msgs[j].flags = msgs[i].flags;
+			new_msgs[j].buf = msgs[i].buf;
+			new_msgs[j].len = msgs[i].len;
+			continue;
+		}
+
+		if (p + msgs[i].len + 2 > bufend)
+			break;
+		p[0] = TC90522_I2C_THRU_REG;
+		p[1] = msgs[i].addr << 1;
+		memcpy(p + 2, msgs[i].buf, msgs[i].len);
+		new_msgs[j].buf = p;
+		new_msgs[j].len = msgs[i].len + 2;
+		p += new_msgs[j].len;
+	}
+
+	if (i < num)
+		ret = -ENOMEM;
+	else
+		ret = i2c_transfer(state->i2c_client->adapter, new_msgs, j);
+	if (ret >= 0 && ret < j)
+		ret = -EIO;
+	kfree(new_msgs);
+	return (ret == j) ? num : ret;
+}
+
+u32 tc90522_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm tc90522_tuner_i2c_algo = {
+	.master_xfer   = &tc90522_master_xfer,
+	.functionality = &tc90522_functionality,
+};
+
+
+/*
+ * I2C driver functions
+ */
+
+static const struct dvb_frontend_ops tc90522_ops_sat = {
+	.delsys = { SYS_ISDBS },
+	.info = {
+		.name = "Toshiba TC90522 ISDB-S module",
+		.frequency_min =  950000,
+		.frequency_max = 2150000,
+		.caps = FE_CAN_INVERSION_AUTO | FE_CAN_FEC_AUTO |
+			FE_CAN_QAM_AUTO | FE_CAN_TRANSMISSION_MODE_AUTO |
+			FE_CAN_GUARD_INTERVAL_AUTO | FE_CAN_HIERARCHY_AUTO,
+	},
+
+	.init = tc90522_init,
+	.sleep = tc90522_sleep,
+	.set_frontend = tc90522_set_frontend,
+	.get_tune_settings = tc90522_get_tune_settings,
+
+	.get_frontend = tc90522s_get_frontend,
+	.read_status = tc90522s_read_status,
+};
+
+static const struct dvb_frontend_ops tc90522_ops_ter = {
+	.delsys = { SYS_ISDBT },
+	.info = {
+		.name = "Toshiba TC90522 ISDB-T module",
+		.frequency_min = 470000000,
+		.frequency_max = 770000000,
+		.frequency_stepsize = 142857,
+		.caps = FE_CAN_INVERSION_AUTO |
+			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_RECOVER |
+			FE_CAN_HIERARCHY_AUTO,
+	},
+
+	.init = tc90522_init,
+	.sleep = tc90522_sleep,
+	.set_frontend = tc90522_set_frontend,
+	.get_tune_settings = tc90522_get_tune_settings,
+
+	.get_frontend = tc90522t_get_frontend,
+	.read_status = tc90522t_read_status,
+};
+
+
+static int tc90522_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct tc90522_state *state;
+	struct tc90522_config *cfg;
+	const struct dvb_frontend_ops *ops;
+	struct i2c_adapter *adap;
+	int ret;
+
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return -ENOMEM;
+	state->i2c_client = client;
+
+	cfg = client->dev.platform_data;
+	memcpy(&state->cfg, cfg, sizeof(state->cfg));
+	cfg->fe = state->cfg.fe = &state->fe;
+	ops =  id->driver_data == 0 ? &tc90522_ops_sat : &tc90522_ops_ter;
+	memcpy(&state->fe.ops, ops, sizeof(*ops));
+	state->fe.demodulator_priv = state;
+
+	adap = &state->tuner_i2c;
+	adap->owner = THIS_MODULE;
+	adap->algo = &tc90522_tuner_i2c_algo;
+	adap->dev.parent = &client->dev;
+	strlcpy(adap->name, "tc90522_sub", sizeof(adap->name));
+	i2c_set_adapdata(adap, state);
+	ret = i2c_add_adapter(adap);
+	if (ret < 0)
+		goto err;
+	cfg->tuner_i2c = state->cfg.tuner_i2c = adap;
+
+	i2c_set_clientdata(client, &state->cfg);
+	dev_info(&client->dev, "Toshiba TC90522 attached.\n");
+	return 0;
+
+err:
+	kfree(state);
+	return ret;
+}
+
+static int tc90522_remove(struct i2c_client *client)
+{
+	struct tc90522_state *state;
+
+	state = cfg_to_state(i2c_get_clientdata(client));
+	i2c_del_adapter(&state->tuner_i2c);
+	kfree(state);
+	return 0;
+}
+
+
+static const struct i2c_device_id tc90522_id[] = {
+	{ TC90522_I2C_DEV_SAT, 0 },
+	{ TC90522_I2C_DEV_TER, 1 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, tc90522_id);
+
+static struct i2c_driver tc90522_driver = {
+	.driver = {
+		.name	= "tc90522",
+	},
+	.probe		= tc90522_probe,
+	.remove		= tc90522_remove,
+	.id_table	= tc90522_id,
+};
+
+module_i2c_driver(tc90522_driver);
+
+MODULE_DESCRIPTION("Toshiba TC90522 frontend");
+MODULE_AUTHOR("Akihiro TSUKADA");
+MODULE_LICENSE("GPL");

drivers/media/dvb-frontends/tc90522.h

···
+/*
+ * Toshiba TC90522 Demodulator
+ *
+ * Copyright (C) 2014 Akihiro Tsukada <[e-mail]>
+ *
+ * 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 version 2.
+ *
+ *
+ * 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.
+ */
+
+/*
+ * The demod has 4 input (2xISDB-T and 2xISDB-S),
+ * and provides independent sub modules for each input.
+ * As the sub modules work in parallel and have the separate i2c addr's,
+ * this driver treats each sub module as one demod device.
+ */
+
+#ifndef TC90522_H
+#define TC90522_H
+
+#include <linux/i2c.h>
+#include "dvb_frontend.h"
+
+/* I2C device types */
+#define TC90522_I2C_DEV_SAT "tc90522sat"
+#define TC90522_I2C_DEV_TER "tc90522ter"
+
+struct tc90522_config {
+	/* [OUT] frontend returned by driver */
+	struct dvb_frontend *fe;
+
+	/* [OUT] tuner I2C adapter returned by driver */
+	struct i2c_adapter *tuner_i2c;
+};
+
+#endif /* TC90522_H */