NFC: trf7970a: Add Target Mode Support

Add target mode support to the trf7970a
NFC driver.  This effectively enables full
Peer-to-Peer support.

To handle changing framing between sending
a response frame and receiving the subsequent
request frame, most of the framing changes
take effect in the interrupt handler and not
in trf7970a_tg_config_framing().

Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 339 insertions, 35 deletions

diff --git a/drivers/nfc/trf7970a.c b/drivers/nfc/trf7970a.c
index 8b109e1..b33cc02 100644
--- a/drivers/nfc/trf7970a.c
+++ b/drivers/nfc/trf7970a.c
@@ -62,7 +62,7 @@
  * way to abort a command that's already been sent to the tag is so turn
  * off power to the tag.  If we do that, though, we'd have to go through
  * the entire anticollision procedure again but the digital layer doesn't
- * support that.  So, if an abort is received before trf7970a_in_send_cmd()
+ * support that.  So, if an abort is received before trf7970a_send_cmd()
  * has sent the command to the tag, it simply returns -ECANCELED.  If the
  * command has already been sent to the tag, then the driver continues
  * normally and recieves the response data (or error) but just before
@@ -121,7 +121,7 @@
 #define TRF7970A_SUPPORTED_PROTOCOLS \
 		(NFC_PROTO_MIFARE_MASK | NFC_PROTO_ISO14443_MASK |	\
 		 NFC_PROTO_ISO14443_B_MASK | NFC_PROTO_FELICA_MASK | \
-		 NFC_PROTO_ISO15693_MASK)
+		 NFC_PROTO_ISO15693_MASK | NFC_PROTO_NFC_DEP_MASK)
 
 #define TRF7970A_AUTOSUSPEND_DELAY		30000 /* 30 seconds */
 
@@ -240,6 +240,15 @@
 #define TRF7970A_ISO_CTRL_14443B_848		0x0f
 #define TRF7970A_ISO_CTRL_FELICA_212		0x1a
 #define TRF7970A_ISO_CTRL_FELICA_424		0x1b
+#define TRF7970A_ISO_CTRL_NFC_NFCA_106		0x01
+#define TRF7970A_ISO_CTRL_NFC_NFCF_212		0x02
+#define TRF7970A_ISO_CTRL_NFC_NFCF_424		0x03
+#define TRF7970A_ISO_CTRL_NFC_CE_14443A		0x00
+#define TRF7970A_ISO_CTRL_NFC_CE_14443B		0x01
+#define TRF7970A_ISO_CTRL_NFC_CE		BIT(2)
+#define TRF7970A_ISO_CTRL_NFC_ACTIVE		BIT(3)
+#define TRF7970A_ISO_CTRL_NFC_INITIATOR		BIT(4)
+#define TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE	BIT(5)
 #define TRF7970A_ISO_CTRL_RFID			BIT(5)
 #define TRF7970A_ISO_CTRL_DIR_MODE		BIT(6)
 #define TRF7970A_ISO_CTRL_RX_CRC_N		BIT(7)	/* true == No CRC */
@@ -265,12 +274,32 @@
 #define TRF7970A_MODULATOR_EN_OOK		BIT(6)
 #define TRF7970A_MODULATOR_27MHZ		BIT(7)
 
+#define TRF7970A_RX_SPECIAL_SETTINGS_NO_LIM	BIT(0)
+#define TRF7970A_RX_SPECIAL_SETTINGS_AGCR	BIT(1)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_0DB	(0x0 << 2)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_5DB	(0x1 << 2)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_10DB	(0x2 << 2)
+#define TRF7970A_RX_SPECIAL_SETTINGS_GD_15DB	(0x3 << 2)
+#define TRF7970A_RX_SPECIAL_SETTINGS_HBT	BIT(4)
+#define TRF7970A_RX_SPECIAL_SETTINGS_M848	BIT(5)
+#define TRF7970A_RX_SPECIAL_SETTINGS_C424	BIT(6)
+#define TRF7970A_RX_SPECIAL_SETTINGS_C212	BIT(7)
+
+#define TRF7970A_REG_IO_CTRL_VRS(v)		((v) & 0x07)
+#define TRF7970A_REG_IO_CTRL_IO_LOW		BIT(5)
+#define TRF7970A_REG_IO_CTRL_EN_EXT_PA		BIT(6)
+#define TRF7970A_REG_IO_CTRL_AUTO_REG		BIT(7)
+
 /* IRQ Status Register Bits */
 #define TRF7970A_IRQ_STATUS_NORESP		BIT(0) /* ISO15693 only */
+#define TRF7970A_IRQ_STATUS_NFC_COL_ERROR	BIT(0)
 #define TRF7970A_IRQ_STATUS_COL			BIT(1)
 #define TRF7970A_IRQ_STATUS_FRAMING_EOF_ERROR	BIT(2)
+#define TRF7970A_IRQ_STATUS_NFC_RF		BIT(2)
 #define TRF7970A_IRQ_STATUS_PARITY_ERROR	BIT(3)
+#define TRF7970A_IRQ_STATUS_NFC_SDD		BIT(3)
 #define TRF7970A_IRQ_STATUS_CRC_ERROR		BIT(4)
+#define TRF7970A_IRQ_STATUS_NFC_PROTO_ERROR	BIT(4)
 #define TRF7970A_IRQ_STATUS_FIFO		BIT(5)
 #define TRF7970A_IRQ_STATUS_SRX			BIT(6)
 #define TRF7970A_IRQ_STATUS_TX			BIT(7)
@@ -301,6 +330,16 @@
 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_16	0x2
 #define TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32	0x3
 
+#define TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(v)	((v) & 0x07)
+#define TRF7970A_NFC_LOW_FIELD_LEVEL_CLEX_DIS	BIT(7)
+
+#define TRF7970A_NFC_TARGET_LEVEL_RFDET(v)	((v) & 0x07)
+#define TRF7970A_NFC_TARGET_LEVEL_HI_RF		BIT(3)
+#define TRF7970A_NFC_TARGET_LEVEL_SDD_EN	BIT(3)
+#define TRF7970A_NFC_TARGET_LEVEL_LD_S_4BYTES	(0x0 << 6)
+#define TRF7970A_NFC_TARGET_LEVEL_LD_S_7BYTES	(0x1 << 6)
+#define TRF7970A_NFC_TARGET_LEVEL_LD_S_10BYTES	(0x2 << 6)
+
 #define TRF7970A_FIFO_STATUS_OVERFLOW		BIT(7)
 
 /* NFC (ISO/IEC 14443A) Type 2 Tag commands */
@@ -345,6 +384,7 @@ enum trf7970a_state {
 	TRF7970A_ST_WAIT_FOR_RX_DATA,
 	TRF7970A_ST_WAIT_FOR_RX_DATA_CONT,
 	TRF7970A_ST_WAIT_TO_ISSUE_EOF,
+	TRF7970A_ST_LISTENING,
 	TRF7970A_ST_MAX
 };
 
@@ -355,6 +395,7 @@ struct trf7970a {
 	struct regulator		*regulator;
 	struct nfc_digital_dev		*ddev;
 	u32				quirks;
+	bool				is_initiator;
 	bool				aborting;
 	struct sk_buff			*tx_skb;
 	struct sk_buff			*rx_skb;
@@ -694,7 +735,7 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 {
 	struct trf7970a *trf = dev_id;
 	int ret;
-	u8 status, fifo_bytes;
+	u8 status, fifo_bytes, iso_ctrl;
 
 	mutex_lock(&trf->lock);
 
@@ -720,12 +761,12 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 	switch (trf->state) {
 	case TRF7970A_ST_IDLE:
 	case TRF7970A_ST_IDLE_RX_BLOCKED:
-		/* If getting interrupts caused by RF noise, turn off the
-		 * receiver to avoid unnecessary interrupts.  It will be
-		 * turned back on in trf7970a_in_send_cmd() when the next
-		 * command is issued.
+		/* If initiator and getting interrupts caused by RF noise,
+		 * turn off the receiver to avoid unnecessary interrupts.
+		 * It will be turned back on in trf7970a_send_cmd() when
+		 * the next command is issued.
 		 */
-		if (status & TRF7970A_IRQ_STATUS_ERROR) {
+		if (trf->is_initiator && (status & TRF7970A_IRQ_STATUS_ERROR)) {
 			trf7970a_cmd(trf, TRF7970A_CMD_BLOCK_RX);
 			trf->state = TRF7970A_ST_IDLE_RX_BLOCKED;
 		}
@@ -757,7 +798,10 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 				trf7970a_send_err_upstream(trf, ret);
 			else if (!fifo_bytes)
 				trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
-		} else if (status == TRF7970A_IRQ_STATUS_TX) {
+		} else if ((status == TRF7970A_IRQ_STATUS_TX) ||
+				(!trf->is_initiator &&
+				 (status == (TRF7970A_IRQ_STATUS_TX |
+					     TRF7970A_IRQ_STATUS_NFC_RF)))) {
 			trf7970a_cmd(trf, TRF7970A_CMD_FIFO_RESET);
 
 			if (!trf->timeout) {
@@ -767,6 +811,45 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 				trf7970a_send_upstream(trf);
 				break;
 			}
+
+			if (trf->is_initiator)
+				break;
+
+			iso_ctrl = trf->iso_ctrl;
+
+			switch (trf->framing) {
+			case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
+				trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
+				iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
+				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
+				break;
+			case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
+				trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
+				iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
+				trf->iso_ctrl = 0xff; /* Force ISO_CTRL write */
+				break;
+			case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
+				ret = trf7970a_write(trf,
+					TRF7970A_SPECIAL_FCN_REG1,
+					TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL);
+				if (ret)
+					return ret;
+
+				trf->special_fcn_reg1 =
+					TRF7970A_SPECIAL_FCN_REG1_14_ANTICOLL;
+				break;
+			default:
+				break;
+			}
+
+			if (iso_ctrl != trf->iso_ctrl) {
+				ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
+						iso_ctrl);
+				if (ret)
+					return ret;
+
+				trf->iso_ctrl = iso_ctrl;
+			}
 		} else {
 			trf7970a_send_err_upstream(trf, -EIO);
 		}
@@ -775,6 +858,15 @@ static irqreturn_t trf7970a_irq(int irq, void *dev_id)
 		if (status != TRF7970A_IRQ_STATUS_TX)
 			trf7970a_send_err_upstream(trf, -EIO);
 		break;
+	case TRF7970A_ST_LISTENING:
+		if (status & TRF7970A_IRQ_STATUS_SRX) {
+			trf->ignore_timeout =
+				!cancel_delayed_work(&trf->timeout_work);
+			trf7970a_drain_fifo(trf, status);
+		} else if (!(status & TRF7970A_IRQ_STATUS_NFC_RF)) {
+			trf7970a_send_err_upstream(trf, -EIO);
+		}
+		break;
 	default:
 		dev_err(trf->dev, "%s - Driver in invalid state: %d\n",
 				__func__, trf->state);
@@ -853,11 +945,6 @@ static int trf7970a_init(struct trf7970a *trf)
 
 	trf->modulator_sys_clk_ctrl = 0;
 
-	/* Must clear NFC Target Detection Level reg due to erratum */
-	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
-	if (ret)
-		goto err_out;
-
 	ret = trf7970a_write(trf, TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS,
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLH_96 |
 			TRF7970A_ADJUTABLE_FIFO_IRQ_LEVELS_WLL_32);
@@ -958,6 +1045,8 @@ static int trf7970a_switch_rf(struct nfc_digital_dev *ddev, bool on)
 			/* FALLTHROUGH */
 		case TRF7970A_ST_IDLE:
 		case TRF7970A_ST_IDLE_RX_BLOCKED:
+		case TRF7970A_ST_WAIT_FOR_RX_DATA:
+		case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 			trf7970a_switch_rf_off(trf);
 		}
 	}
@@ -1005,6 +1094,14 @@ static int trf7970a_in_config_rf_tech(struct trf7970a *trf, int tech)
 
 	trf->technology = tech;
 
+	/* If in initiator mode and not changing the RF tech due to a
+	 * PSL sequence (indicated by 'trf->iso_ctrl == 0xff' from
+	 * trf7970a_init()), clear the NFC Target Detection Level register
+	 * due to erratum.
+	 */
+	if (trf->iso_ctrl == 0xff)
+		ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL, 0);
+
 	return ret;
 }
 
@@ -1063,6 +1160,8 @@ static int trf7970a_in_config_framing(struct trf7970a *trf, int framing)
 	case NFC_DIGITAL_FRAMING_NFCF_T3T:
 	case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
 	case NFC_DIGITAL_FRAMING_ISO15693_T5T:
+	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
+	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
 		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
 		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
 		break;
@@ -1124,6 +1223,8 @@ static int trf7970a_in_configure_hw(struct nfc_digital_dev *ddev, int type,
 
 	mutex_lock(&trf->lock);
 
+	trf->is_initiator = true;
+
 	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
 			(trf->state == TRF7970A_ST_RF_OFF)) {
 		ret = trf7970a_switch_rf_on(trf);
@@ -1233,7 +1334,7 @@ static int trf7970a_per_cmd_config(struct trf7970a *trf, struct sk_buff *skb)
 	return 0;
 }
 
-static int trf7970a_in_send_cmd(struct nfc_digital_dev *ddev,
+static int trf7970a_send_cmd(struct nfc_digital_dev *ddev,
 		struct sk_buff *skb, u16 timeout,
 		nfc_digital_cmd_complete_t cb, void *arg)
 {
@@ -1284,9 +1385,11 @@ static int trf7970a_in_send_cmd(struct nfc_digital_dev *ddev,
 		trf->state = TRF7970A_ST_IDLE;
 	}
 
-	ret = trf7970a_per_cmd_config(trf, skb);
-	if (ret)
-		goto out_err;
+	if (trf->is_initiator) {
+		ret = trf7970a_per_cmd_config(trf, skb);
+		if (ret)
+			goto out_err;
+	}
 
 	trf->ddev = ddev;
 	trf->tx_skb = skb;
@@ -1335,35 +1438,229 @@ out_err:
 	return ret;
 }
 
-static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev,
-		int type, int param)
+static int trf7970a_tg_config_rf_tech(struct trf7970a *trf, int tech)
 {
-	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
+	int ret = 0;
+
+	dev_dbg(trf->dev, "rf technology: %d\n", tech);
+
+	switch (tech) {
+	case NFC_DIGITAL_RF_TECH_106A:
+		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
+			TRF7970A_ISO_CTRL_NFC_CE |
+			TRF7970A_ISO_CTRL_NFC_CE_14443A;
+		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_OOK;
+		break;
+	case NFC_DIGITAL_RF_TECH_212F:
+		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
+			TRF7970A_ISO_CTRL_NFC_NFCF_212;
+		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		break;
+	case NFC_DIGITAL_RF_TECH_424F:
+		trf->iso_ctrl_tech = TRF7970A_ISO_CTRL_NFC_NFC_CE_MODE |
+			TRF7970A_ISO_CTRL_NFC_NFCF_424;
+		trf->modulator_sys_clk_ctrl = TRF7970A_MODULATOR_DEPTH_ASK10;
+		break;
+	default:
+		dev_dbg(trf->dev, "Unsupported rf technology: %d\n", tech);
+		return -EINVAL;
+	}
+
+	trf->technology = tech;
 
-	dev_dbg(trf->dev, "Unsupported interface\n");
+	/* Normally we write the ISO_CTRL register in
+	 * trf7970a_tg_config_framing() because the framing can change
+	 * the value written.  However, when sending a PSL RES,
+	 * digital_tg_send_psl_res_complete() doesn't call
+	 * trf7970a_tg_config_framing() so we must write the register
+	 * here.
+	 */
+	if ((trf->framing == NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED) &&
+			(trf->iso_ctrl_tech != trf->iso_ctrl)) {
+		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL,
+				trf->iso_ctrl_tech);
+
+		trf->iso_ctrl = trf->iso_ctrl_tech;
+	}
 
-	return -EINVAL;
+	return ret;
 }
 
-static int trf7970a_tg_send_cmd(struct nfc_digital_dev *ddev,
-		struct sk_buff *skb, u16 timeout,
-		nfc_digital_cmd_complete_t cb, void *arg)
+/* Since this is a target routine, several of the framing calls are
+ * made between receiving the request and sending the response so they
+ * should take effect until after the response is sent.  This is accomplished
+ * by skipping the ISO_CTRL register write here and doing it in the interrupt
+ * handler.
+ */
+static int trf7970a_tg_config_framing(struct trf7970a *trf, int framing)
+{
+	u8 iso_ctrl = trf->iso_ctrl_tech;
+	int ret;
+
+	dev_dbg(trf->dev, "framing: %d\n", framing);
+
+	switch (framing) {
+	case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
+		trf->tx_cmd = TRF7970A_CMD_TRANSMIT_NO_CRC;
+		iso_ctrl |= TRF7970A_ISO_CTRL_RX_CRC_N;
+		break;
+	case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
+	case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
+	case NFC_DIGITAL_FRAMING_NFCA_ANTICOL_COMPLETE:
+		/* These ones are applied in the interrupt handler */
+		iso_ctrl = trf->iso_ctrl; /* Don't write to ISO_CTRL yet */
+		break;
+	case NFC_DIGITAL_FRAMING_NFCF_NFC_DEP:
+		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
+		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
+		break;
+	case NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED:
+		trf->tx_cmd = TRF7970A_CMD_TRANSMIT;
+		iso_ctrl &= ~TRF7970A_ISO_CTRL_RX_CRC_N;
+		break;
+	default:
+		dev_dbg(trf->dev, "Unsupported Framing: %d\n", framing);
+		return -EINVAL;
+	}
+
+	trf->framing = framing;
+
+	if (iso_ctrl != trf->iso_ctrl) {
+		ret = trf7970a_write(trf, TRF7970A_ISO_CTRL, iso_ctrl);
+		if (ret)
+			return ret;
+
+		trf->iso_ctrl = iso_ctrl;
+
+		ret = trf7970a_write(trf, TRF7970A_MODULATOR_SYS_CLK_CTRL,
+				trf->modulator_sys_clk_ctrl);
+		if (ret)
+			return ret;
+	}
+
+	if (!(trf->chip_status_ctrl & TRF7970A_CHIP_STATUS_RF_ON)) {
+		ret = trf7970a_write(trf, TRF7970A_CHIP_STATUS_CTRL,
+				trf->chip_status_ctrl |
+					TRF7970A_CHIP_STATUS_RF_ON);
+		if (ret)
+			return ret;
+
+		trf->chip_status_ctrl |= TRF7970A_CHIP_STATUS_RF_ON;
+	}
+
+	return 0;
+}
+
+static int trf7970a_tg_configure_hw(struct nfc_digital_dev *ddev, int type,
+		int param)
 {
 	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
+	int ret;
+
+	dev_dbg(trf->dev, "Configure hw - type: %d, param: %d\n", type, param);
+
+	mutex_lock(&trf->lock);
+
+	trf->is_initiator = false;
 
-	dev_dbg(trf->dev, "Unsupported interface\n");
+	if ((trf->state == TRF7970A_ST_PWR_OFF) ||
+			(trf->state == TRF7970A_ST_RF_OFF)) {
+		ret = trf7970a_switch_rf_on(trf);
+		if (ret)
+			goto err_unlock;
+	}
+
+	switch (type) {
+	case NFC_DIGITAL_CONFIG_RF_TECH:
+		ret = trf7970a_tg_config_rf_tech(trf, param);
+		break;
+	case NFC_DIGITAL_CONFIG_FRAMING:
+		ret = trf7970a_tg_config_framing(trf, param);
+		break;
+	default:
+		dev_dbg(trf->dev, "Unknown type: %d\n", type);
+		ret = -EINVAL;
+	}
 
-	return -EINVAL;
+err_unlock:
+	mutex_unlock(&trf->lock);
+	return ret;
 }
 
-static int trf7970a_tg_listen(struct nfc_digital_dev *ddev,
-		u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)
+static int trf7970a_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,
+		nfc_digital_cmd_complete_t cb, void *arg)
 {
 	struct trf7970a *trf = nfc_digital_get_drvdata(ddev);
+	int ret;
+
+	dev_dbg(trf->dev, "Listen - state: %d, timeout: %d ms\n",
+			trf->state, timeout);
+
+	mutex_lock(&trf->lock);
 
-	dev_dbg(trf->dev, "Unsupported interface\n");
+	if ((trf->state != TRF7970A_ST_IDLE) &&
+			(trf->state != TRF7970A_ST_IDLE_RX_BLOCKED)) {
+		dev_err(trf->dev, "%s - Bogus state: %d\n", __func__,
+				trf->state);
+		ret = -EIO;
+		goto out_err;
+	}
+
+	if (trf->aborting) {
+		dev_dbg(trf->dev, "Abort process complete\n");
+		trf->aborting = false;
+		ret = -ECANCELED;
+		goto out_err;
+	}
+
+	trf->rx_skb = nfc_alloc_recv_skb(TRF7970A_RX_SKB_ALLOC_SIZE,
+			GFP_KERNEL);
+	if (!trf->rx_skb) {
+		dev_dbg(trf->dev, "Can't alloc rx_skb\n");
+		ret = -ENOMEM;
+		goto out_err;
+	}
+
+	ret = trf7970a_write(trf, TRF7970A_RX_SPECIAL_SETTINGS,
+			TRF7970A_RX_SPECIAL_SETTINGS_HBT |
+			TRF7970A_RX_SPECIAL_SETTINGS_M848 |
+			TRF7970A_RX_SPECIAL_SETTINGS_C424 |
+			TRF7970A_RX_SPECIAL_SETTINGS_C212);
+	if (ret)
+		return ret;
+
+	ret = trf7970a_write(trf, TRF7970A_REG_IO_CTRL,
+			TRF7970A_REG_IO_CTRL_VRS(0x1));
+	if (ret)
+		return ret;
 
-	return -EINVAL;
+	ret = trf7970a_write(trf, TRF7970A_NFC_LOW_FIELD_LEVEL,
+			TRF7970A_NFC_LOW_FIELD_LEVEL_RFDET(0x3));
+	if (ret)
+		return ret;
+
+	ret = trf7970a_write(trf, TRF7970A_NFC_TARGET_LEVEL,
+			TRF7970A_NFC_TARGET_LEVEL_RFDET(0x7));
+	if (ret)
+		return ret;
+
+	trf->ddev = ddev;
+	trf->cb = cb;
+	trf->cb_arg = arg;
+	trf->timeout = timeout;
+	trf->ignore_timeout = false;
+
+	ret = trf7970a_cmd(trf, TRF7970A_CMD_ENABLE_RX);
+	if (ret)
+		goto out_err;
+
+	trf->state = TRF7970A_ST_LISTENING;
+
+	schedule_delayed_work(&trf->timeout_work, msecs_to_jiffies(timeout));
+
+out_err:
+	mutex_unlock(&trf->lock);
+	return ret;
 }
 
 static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
@@ -1381,6 +1678,11 @@ static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
 	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
 		trf->aborting = true;
 		break;
+	case TRF7970A_ST_LISTENING:
+		trf->ignore_timeout = !cancel_delayed_work(&trf->timeout_work);
+		trf7970a_send_err_upstream(trf, -ECANCELED);
+		dev_dbg(trf->dev, "Abort process complete\n");
+		break;
 	default:
 		break;
 	}
@@ -1390,9 +1692,9 @@ static void trf7970a_abort_cmd(struct nfc_digital_dev *ddev)
 
 static struct nfc_digital_ops trf7970a_nfc_ops = {
 	.in_configure_hw	= trf7970a_in_configure_hw,
-	.in_send_cmd		= trf7970a_in_send_cmd,
+	.in_send_cmd		= trf7970a_send_cmd,
 	.tg_configure_hw	= trf7970a_tg_configure_hw,
-	.tg_send_cmd		= trf7970a_tg_send_cmd,
+	.tg_send_cmd		= trf7970a_send_cmd,
 	.tg_listen		= trf7970a_tg_listen,
 	.switch_rf		= trf7970a_switch_rf,
 	.abort_cmd		= trf7970a_abort_cmd,
@@ -1479,6 +1781,7 @@ static void trf7970a_shutdown(struct trf7970a *trf)
 	case TRF7970A_ST_WAIT_FOR_RX_DATA:
 	case TRF7970A_ST_WAIT_FOR_RX_DATA_CONT:
 	case TRF7970A_ST_WAIT_TO_ISSUE_EOF:
+	case TRF7970A_ST_LISTENING:
 		trf7970a_send_err_upstream(trf, -ECANCELED);
 		/* FALLTHROUGH */
 	case TRF7970A_ST_IDLE:
@@ -1606,7 +1909,8 @@ static int trf7970a_probe(struct spi_device *spi)
 
 	trf->ddev = nfc_digital_allocate_device(&trf7970a_nfc_ops,
 			TRF7970A_SUPPORTED_PROTOCOLS,
-			NFC_DIGITAL_DRV_CAPS_IN_CRC, 0, 0);
+			NFC_DIGITAL_DRV_CAPS_IN_CRC |
+				NFC_DIGITAL_DRV_CAPS_TG_CRC, 0, 0);
 	if (!trf->ddev) {
 		dev_err(trf->dev, "Can't allocate NFC digital device\n");
 		ret = -ENOMEM;