net/nfc/digital_core.c - kernel/msm-5.4 - Gitiles

 /*
  * NFC Digital Protocol stack
  * Copyright (c) 2013, Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope 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.
  *
  */

 #define pr_fmt(fmt) "digital: %s: " fmt, __func__

 #include <linux/module.h>

 #include "digital.h"

 #define DIGITAL_PROTO_NFCA_RF_TECH \
 	(NFC_PROTO_JEWEL_MASK | NFC_PROTO_MIFARE_MASK | NFC_PROTO_NFC_DEP_MASK)

 #define DIGITAL_PROTO_NFCF_RF_TECH \
 	(NFC_PROTO_FELICA_MASK | NFC_PROTO_NFC_DEP_MASK)

 #define DIGITAL_PROTO_ISO15693_RF_TECH	NFC_PROTO_ISO15693_MASK

 struct digital_cmd {
 	struct list_head queue;

 	u8 type;
 	u8 pending;

 	u16 timeout;
 	struct sk_buff *req;
 	struct sk_buff *resp;
 	struct digital_tg_mdaa_params *mdaa_params;

 	nfc_digital_cmd_complete_t cmd_cb;
 	void *cb_context;
 };

 struct sk_buff *digital_skb_alloc(struct nfc_digital_dev *ddev,
 				  unsigned int len)
 {
 	struct sk_buff *skb;

 	skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
 			GFP_KERNEL);
 	if (skb)
 		skb_reserve(skb, ddev->tx_headroom);

 	return skb;
 }

 void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
 			 u8 bitwise_inv, u8 msb_first)
 {
 	u16 crc;

 	crc = crc_func(init, skb->data, skb->len);

 	if (bitwise_inv)
 		crc = ~crc;

 	if (msb_first)
 		crc = __fswab16(crc);

 	*skb_put(skb, 1) = crc & 0xFF;
 	*skb_put(skb, 1) = (crc >> 8) & 0xFF;
 }

 int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
 			  u16 crc_init, u8 bitwise_inv, u8 msb_first)
 {
 	int rc;
 	u16 crc;

 	if (skb->len <= 2)
 		return -EIO;

 	crc = crc_func(crc_init, skb->data, skb->len - 2);

 	if (bitwise_inv)
 		crc = ~crc;

 	if (msb_first)
 		crc = __swab16(crc);

 	rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
 	     (skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));

 	if (rc)
 		return -EIO;

 	skb_trim(skb, skb->len - 2);

 	return 0;
 }

 static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
 {
 	ddev->ops->switch_rf(ddev, on);
 }

 static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
 {
 	ddev->ops->abort_cmd(ddev);
 }

 static void digital_wq_cmd_complete(struct work_struct *work)
 {
 	struct digital_cmd *cmd;
 	struct nfc_digital_dev *ddev = container_of(work,
 						    struct nfc_digital_dev,
 						    cmd_complete_work);

 	mutex_lock(&ddev->cmd_lock);

 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
 				       queue);
 	if (!cmd) {
 		mutex_unlock(&ddev->cmd_lock);
 		return;
 	}

 	list_del(&cmd->queue);

 	mutex_unlock(&ddev->cmd_lock);

 	if (!IS_ERR(cmd->resp))
 		print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
 				     cmd->resp->data, cmd->resp->len, false);

 	cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);

 	kfree(cmd->mdaa_params);
 	kfree(cmd);

 	schedule_work(&ddev->cmd_work);
 }

 static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
 				      void *arg, struct sk_buff *resp)
 {
 	struct digital_cmd *cmd = arg;

 	cmd->resp = resp;

 	schedule_work(&ddev->cmd_complete_work);
 }

 static void digital_wq_cmd(struct work_struct *work)
 {
 	int rc;
 	struct digital_cmd *cmd;
 	struct digital_tg_mdaa_params *params;
 	struct nfc_digital_dev *ddev = container_of(work,
 						    struct nfc_digital_dev,
 						    cmd_work);

 	mutex_lock(&ddev->cmd_lock);

 	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
 				       queue);
 	if (!cmd || cmd->pending) {
 		mutex_unlock(&ddev->cmd_lock);
 		return;
 	}

 	mutex_unlock(&ddev->cmd_lock);

 	if (cmd->req)
 		print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
 				     cmd->req->data, cmd->req->len, false);

 	switch (cmd->type) {
 	case DIGITAL_CMD_IN_SEND:
 		rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
 					    digital_send_cmd_complete, cmd);
 		break;

 	case DIGITAL_CMD_TG_SEND:
 		rc = ddev->ops->tg_send_cmd(ddev, cmd->req, cmd->timeout,
 					    digital_send_cmd_complete, cmd);
 		break;

 	case DIGITAL_CMD_TG_LISTEN:
 		rc = ddev->ops->tg_listen(ddev, cmd->timeout,
 					  digital_send_cmd_complete, cmd);
 		break;

 	case DIGITAL_CMD_TG_LISTEN_MDAA:
 		params = cmd->mdaa_params;

 		rc = ddev->ops->tg_listen_mdaa(ddev, params, cmd->timeout,
 					       digital_send_cmd_complete, cmd);
 		break;

 	default:
 		pr_err("Unknown cmd type %d\n", cmd->type);
 		return;
 	}

 	if (!rc)
 		return;

 	pr_err("in_send_command returned err %d\n", rc);

 	mutex_lock(&ddev->cmd_lock);
 	list_del(&cmd->queue);
 	mutex_unlock(&ddev->cmd_lock);

 	kfree_skb(cmd->req);
 	kfree(cmd->mdaa_params);
 	kfree(cmd);

 	schedule_work(&ddev->cmd_work);
 }

 int digital_send_cmd(struct nfc_digital_dev *ddev, u8 cmd_type,
 		     struct sk_buff *skb, struct digital_tg_mdaa_params *params,
 		     u16 timeout, nfc_digital_cmd_complete_t cmd_cb,
 		     void *cb_context)
 {
 	struct digital_cmd *cmd;

 	cmd = kzalloc(sizeof(struct digital_cmd), GFP_KERNEL);
 	if (!cmd)
 		return -ENOMEM;

 	cmd->type = cmd_type;
 	cmd->timeout = timeout;
 	cmd->req = skb;
 	cmd->mdaa_params = params;
 	cmd->cmd_cb = cmd_cb;
 	cmd->cb_context = cb_context;
 	INIT_LIST_HEAD(&cmd->queue);

 	mutex_lock(&ddev->cmd_lock);
 	list_add_tail(&cmd->queue, &ddev->cmd_queue);
 	mutex_unlock(&ddev->cmd_lock);

 	schedule_work(&ddev->cmd_work);

 	return 0;
 }

 int digital_in_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
 {
 	int rc;

 	rc = ddev->ops->in_configure_hw(ddev, type, param);
 	if (rc)
 		pr_err("in_configure_hw failed: %d\n", rc);

 	return rc;
 }

 int digital_tg_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
 {
 	int rc;

 	rc = ddev->ops->tg_configure_hw(ddev, type, param);
 	if (rc)
 		pr_err("tg_configure_hw failed: %d\n", rc);

 	return rc;
 }

 static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
 {
 	struct digital_tg_mdaa_params *params;

 	params = kzalloc(sizeof(struct digital_tg_mdaa_params), GFP_KERNEL);
 	if (!params)
 		return -ENOMEM;

 	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
 	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
 	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;

 	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
 	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
 	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
 	params->sc = DIGITAL_SENSF_FELICA_SC;

 	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
 				500, digital_tg_recv_atr_req, NULL);
 }

 int digital_target_found(struct nfc_digital_dev *ddev,
 			 struct nfc_target *target, u8 protocol)
 {
 	int rc;
 	u8 framing;
 	u8 rf_tech;
 	int (*check_crc)(struct sk_buff *skb);
 	void (*add_crc)(struct sk_buff *skb);

 	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;

 	switch (protocol) {
 	case NFC_PROTO_JEWEL:
 		framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
 		check_crc = digital_skb_check_crc_b;
 		add_crc = digital_skb_add_crc_b;
 		break;

 	case NFC_PROTO_MIFARE:
 		framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
 		check_crc = digital_skb_check_crc_a;
 		add_crc = digital_skb_add_crc_a;
 		break;

 	case NFC_PROTO_FELICA:
 		framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
 		check_crc = digital_skb_check_crc_f;
 		add_crc = digital_skb_add_crc_f;
 		break;

 	case NFC_PROTO_NFC_DEP:
 		if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
 			framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
 			check_crc = digital_skb_check_crc_a;
 			add_crc = digital_skb_add_crc_a;
 		} else {
 			framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
 			check_crc = digital_skb_check_crc_f;
 			add_crc = digital_skb_add_crc_f;
 		}
 		break;

 	case NFC_PROTO_ISO15693:
 		framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
 		check_crc = digital_skb_check_crc_b;
 		add_crc = digital_skb_add_crc_b;
 		break;

 	case NFC_PROTO_ISO14443:
 		framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
 		check_crc = digital_skb_check_crc_a;
 		add_crc = digital_skb_add_crc_a;
 		break;

 	default:
 		pr_err("Invalid protocol %d\n", protocol);
 		return -EINVAL;
 	}

 	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);

 	ddev->curr_rf_tech = rf_tech;

 	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
 		ddev->skb_add_crc = digital_skb_add_crc_none;
 		ddev->skb_check_crc = digital_skb_check_crc_none;
 	} else {
 		ddev->skb_add_crc = add_crc;
 		ddev->skb_check_crc = check_crc;
 	}

 	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
 	if (rc)
 		return rc;

 	target->supported_protocols = (1 << protocol);
 	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
 	if (rc)
 		return rc;

 	ddev->poll_tech_count = 0;

 	return 0;
 }

 void digital_poll_next_tech(struct nfc_digital_dev *ddev)
 {
 	digital_switch_rf(ddev, 0);

 	mutex_lock(&ddev->poll_lock);

 	if (!ddev->poll_tech_count) {
 		mutex_unlock(&ddev->poll_lock);
 		return;
 	}

 	ddev->poll_tech_index = (ddev->poll_tech_index + 1) %
 				ddev->poll_tech_count;

 	mutex_unlock(&ddev->poll_lock);

 	schedule_work(&ddev->poll_work);
 }

 static void digital_wq_poll(struct work_struct *work)
 {
 	int rc;
 	struct digital_poll_tech *poll_tech;
 	struct nfc_digital_dev *ddev = container_of(work,
 						    struct nfc_digital_dev,
 						    poll_work);
 	mutex_lock(&ddev->poll_lock);

 	if (!ddev->poll_tech_count) {
 		mutex_unlock(&ddev->poll_lock);
 		return;
 	}

 	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];

 	mutex_unlock(&ddev->poll_lock);

 	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
 	if (rc)
 		digital_poll_next_tech(ddev);
 }

 static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
 				  digital_poll_t poll_func)
 {
 	struct digital_poll_tech *poll_tech;

 	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
 		return;

 	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];

 	poll_tech->rf_tech = rf_tech;
 	poll_tech->poll_func = poll_func;
 }

 /**
  * start_poll operation
  *
  * For every supported protocol, the corresponding polling function is added
  * to the table of polling technologies (ddev->poll_techs[]) using
  * digital_add_poll_tech().
  * When a polling function fails (by timeout or protocol error) the next one is
  * schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
  */
 static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
 			      __u32 tm_protocols)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
 	u32 matching_im_protocols, matching_tm_protocols;

 	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
 		 tm_protocols, ddev->protocols);

 	matching_im_protocols = ddev->protocols & im_protocols;
 	matching_tm_protocols = ddev->protocols & tm_protocols;

 	if (!matching_im_protocols && !matching_tm_protocols) {
 		pr_err("Unknown protocol\n");
 		return -EINVAL;
 	}

 	if (ddev->poll_tech_count) {
 		pr_err("Already polling\n");
 		return -EBUSY;
 	}

 	if (ddev->curr_protocol) {
 		pr_err("A target is already active\n");
 		return -EBUSY;
 	}

 	ddev->poll_tech_count = 0;
 	ddev->poll_tech_index = 0;

 	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
 				      digital_in_send_sens_req);

 	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
 				      digital_in_send_sensf_req);

 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
 				      digital_in_send_sensf_req);
 	}

 	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
 		digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
 				      digital_in_send_iso15693_inv_req);

 	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
 		if (ddev->ops->tg_listen_mdaa) {
 			digital_add_poll_tech(ddev, 0,
 					      digital_tg_listen_mdaa);
 		} else {
 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
 					      digital_tg_listen_nfca);

 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
 					      digital_tg_listen_nfcf);

 			digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
 					      digital_tg_listen_nfcf);
 		}
 	}

 	if (!ddev->poll_tech_count) {
 		pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
 		       matching_im_protocols, matching_tm_protocols);
 		return -EINVAL;
 	}

 	schedule_work(&ddev->poll_work);

 	return 0;
 }

 static void digital_stop_poll(struct nfc_dev *nfc_dev)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	mutex_lock(&ddev->poll_lock);

 	if (!ddev->poll_tech_count) {
 		pr_err("Polling operation was not running\n");
 		mutex_unlock(&ddev->poll_lock);
 		return;
 	}

 	ddev->poll_tech_count = 0;

 	mutex_unlock(&ddev->poll_lock);

 	cancel_work_sync(&ddev->poll_work);

 	digital_abort_cmd(ddev);
 }

 static int digital_dev_up(struct nfc_dev *nfc_dev)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	digital_switch_rf(ddev, 1);

 	return 0;
 }

 static int digital_dev_down(struct nfc_dev *nfc_dev)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	digital_switch_rf(ddev, 0);

 	return 0;
 }

 static int digital_dep_link_up(struct nfc_dev *nfc_dev,
 			       struct nfc_target *target,
 			       __u8 comm_mode, __u8 *gb, size_t gb_len)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
 	int rc;

 	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);

 	if (!rc)
 		ddev->curr_protocol = NFC_PROTO_NFC_DEP;

 	return rc;
 }

 static int digital_dep_link_down(struct nfc_dev *nfc_dev)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	ddev->curr_protocol = 0;

 	return 0;
 }

 static int digital_activate_target(struct nfc_dev *nfc_dev,
 				   struct nfc_target *target, __u32 protocol)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	if (ddev->poll_tech_count) {
 		pr_err("Can't activate a target while polling\n");
 		return -EBUSY;
 	}

 	if (ddev->curr_protocol) {
 		pr_err("A target is already active\n");
 		return -EBUSY;
 	}

 	ddev->curr_protocol = protocol;

 	return 0;
 }

 static void digital_deactivate_target(struct nfc_dev *nfc_dev,
 				      struct nfc_target *target)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

 	if (!ddev->curr_protocol) {
 		pr_err("No active target\n");
 		return;
 	}

 	ddev->curr_protocol = 0;
 }

 static int digital_tg_send(struct nfc_dev *dev, struct sk_buff *skb)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(dev);

 	return digital_tg_send_dep_res(ddev, skb);
 }

 static void digital_in_send_complete(struct nfc_digital_dev *ddev, void *arg,
 				     struct sk_buff *resp)
 {
 	struct digital_data_exch *data_exch = arg;
 	int rc;

 	if (IS_ERR(resp)) {
 		rc = PTR_ERR(resp);
 		resp = NULL;
 		goto done;
 	}

 	if (ddev->curr_protocol == NFC_PROTO_MIFARE) {
 		rc = digital_in_recv_mifare_res(resp);
 		/* crc check is done in digital_in_recv_mifare_res() */
 		goto done;
 	}

 	if (ddev->curr_protocol == NFC_PROTO_ISO14443) {
 		rc = digital_in_iso_dep_pull_sod(ddev, resp);
 		if (rc)
 			goto done;
 	}

 	rc = ddev->skb_check_crc(resp);

 done:
 	if (rc) {
 		kfree_skb(resp);
 		resp = NULL;
 	}

 	data_exch->cb(data_exch->cb_context, resp, rc);

 	kfree(data_exch);
 }

 static int digital_in_send(struct nfc_dev *nfc_dev, struct nfc_target *target,
 			   struct sk_buff *skb, data_exchange_cb_t cb,
 			   void *cb_context)
 {
 	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
 	struct digital_data_exch *data_exch;
 	int rc;

 	data_exch = kzalloc(sizeof(struct digital_data_exch), GFP_KERNEL);
 	if (!data_exch) {
 		pr_err("Failed to allocate data_exch struct\n");
 		return -ENOMEM;
 	}

 	data_exch->cb = cb;
 	data_exch->cb_context = cb_context;

 	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
 		rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
 		goto exit;
 	}

 	if (ddev->curr_protocol == NFC_PROTO_ISO14443) {
 		rc = digital_in_iso_dep_push_sod(ddev, skb);
 		if (rc)
 			goto exit;
 	}

 	ddev->skb_add_crc(skb);

 	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
 				 data_exch);

 exit:
 	if (rc)
 		kfree(data_exch);

 	return rc;
 }

 static struct nfc_ops digital_nfc_ops = {
 	.dev_up = digital_dev_up,
 	.dev_down = digital_dev_down,
 	.start_poll = digital_start_poll,
 	.stop_poll = digital_stop_poll,
 	.dep_link_up = digital_dep_link_up,
 	.dep_link_down = digital_dep_link_down,
 	.activate_target = digital_activate_target,
 	.deactivate_target = digital_deactivate_target,
 	.tm_send = digital_tg_send,
 	.im_transceive = digital_in_send,
 };

 struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
 					    __u32 supported_protocols,
 					    __u32 driver_capabilities,
 					    int tx_headroom, int tx_tailroom)
 {
 	struct nfc_digital_dev *ddev;

 	if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
 	    !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
 	    !ops->switch_rf)
 		return NULL;

 	ddev = kzalloc(sizeof(struct nfc_digital_dev), GFP_KERNEL);
 	if (!ddev)
 		return NULL;

 	ddev->driver_capabilities = driver_capabilities;
 	ddev->ops = ops;

 	mutex_init(&ddev->cmd_lock);
 	INIT_LIST_HEAD(&ddev->cmd_queue);

 	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
 	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);

 	mutex_init(&ddev->poll_lock);
 	INIT_WORK(&ddev->poll_work, digital_wq_poll);

 	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
 		ddev->protocols |= NFC_PROTO_JEWEL_MASK;
 	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
 		ddev->protocols |= NFC_PROTO_MIFARE_MASK;
 	if (supported_protocols & NFC_PROTO_FELICA_MASK)
 		ddev->protocols |= NFC_PROTO_FELICA_MASK;
 	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
 		ddev->protocols |= NFC_PROTO_NFC_DEP_MASK;
 	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
 		ddev->protocols |= NFC_PROTO_ISO15693_MASK;
 	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
 		ddev->protocols |= NFC_PROTO_ISO14443_MASK;

 	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
 	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;

 	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
 					    ddev->tx_headroom,
 					    ddev->tx_tailroom);
 	if (!ddev->nfc_dev) {
 		pr_err("nfc_allocate_device failed\n");
 		goto free_dev;
 	}

 	nfc_set_drvdata(ddev->nfc_dev, ddev);

 	return ddev;

 free_dev:
 	kfree(ddev);

 	return NULL;
 }
 EXPORT_SYMBOL(nfc_digital_allocate_device);

 void nfc_digital_free_device(struct nfc_digital_dev *ddev)
 {
 	nfc_free_device(ddev->nfc_dev);
 	kfree(ddev);
 }
 EXPORT_SYMBOL(nfc_digital_free_device);

 int nfc_digital_register_device(struct nfc_digital_dev *ddev)
 {
 	return nfc_register_device(ddev->nfc_dev);
 }
 EXPORT_SYMBOL(nfc_digital_register_device);

 void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
 {
 	struct digital_cmd *cmd, *n;

 	nfc_unregister_device(ddev->nfc_dev);

 	mutex_lock(&ddev->poll_lock);
 	ddev->poll_tech_count = 0;
 	mutex_unlock(&ddev->poll_lock);

 	cancel_work_sync(&ddev->poll_work);
 	cancel_work_sync(&ddev->cmd_work);
 	cancel_work_sync(&ddev->cmd_complete_work);

 	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
 		list_del(&cmd->queue);
 		kfree(cmd->mdaa_params);
 		kfree(cmd);
 	}
 }
 EXPORT_SYMBOL(nfc_digital_unregister_device);

 MODULE_LICENSE("GPL");
	/*
	* NFC Digital Protocol stack
	* Copyright (c) 2013, Intel Corporation.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope 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.
	*
	*/

	#define pr_fmt(fmt) "digital: %s: " fmt, __func__

	#include <linux/module.h>

	#include "digital.h"

	#define DIGITAL_PROTO_NFCA_RF_TECH \
	(NFC_PROTO_JEWEL_MASK \| NFC_PROTO_MIFARE_MASK \| NFC_PROTO_NFC_DEP_MASK)

	#define DIGITAL_PROTO_NFCF_RF_TECH \
	(NFC_PROTO_FELICA_MASK \| NFC_PROTO_NFC_DEP_MASK)

	#define DIGITAL_PROTO_ISO15693_RF_TECH NFC_PROTO_ISO15693_MASK

	struct digital_cmd {
	struct list_head queue;

	u8 type;
	u8 pending;

	u16 timeout;
	struct sk_buff *req;
	struct sk_buff *resp;
	struct digital_tg_mdaa_params *mdaa_params;

	nfc_digital_cmd_complete_t cmd_cb;
	void *cb_context;
	};

	struct sk_buff digital_skb_alloc(struct nfc_digital_dev ddev,
	unsigned int len)
	{
	struct sk_buff *skb;

	skb = alloc_skb(len + ddev->tx_headroom + ddev->tx_tailroom,
	GFP_KERNEL);
	if (skb)
	skb_reserve(skb, ddev->tx_headroom);

	return skb;
	}

	void digital_skb_add_crc(struct sk_buff *skb, crc_func_t crc_func, u16 init,
	u8 bitwise_inv, u8 msb_first)
	{
	u16 crc;

	crc = crc_func(init, skb->data, skb->len);

	if (bitwise_inv)
	crc = ~crc;

	if (msb_first)
	crc = __fswab16(crc);

	*skb_put(skb, 1) = crc & 0xFF;
	*skb_put(skb, 1) = (crc >> 8) & 0xFF;
	}

	int digital_skb_check_crc(struct sk_buff *skb, crc_func_t crc_func,
	u16 crc_init, u8 bitwise_inv, u8 msb_first)
	{
	int rc;
	u16 crc;

	if (skb->len <= 2)
	return -EIO;

	crc = crc_func(crc_init, skb->data, skb->len - 2);

	if (bitwise_inv)
	crc = ~crc;

	if (msb_first)
	crc = __swab16(crc);

	rc = (skb->data[skb->len - 2] - (crc & 0xFF)) +
	(skb->data[skb->len - 1] - ((crc >> 8) & 0xFF));

	if (rc)
	return -EIO;

	skb_trim(skb, skb->len - 2);

	return 0;
	}

	static inline void digital_switch_rf(struct nfc_digital_dev *ddev, bool on)
	{
	ddev->ops->switch_rf(ddev, on);
	}

	static inline void digital_abort_cmd(struct nfc_digital_dev *ddev)
	{
	ddev->ops->abort_cmd(ddev);
	}

	static void digital_wq_cmd_complete(struct work_struct *work)
	{
	struct digital_cmd *cmd;
	struct nfc_digital_dev *ddev = container_of(work,
	struct nfc_digital_dev,
	cmd_complete_work);

	mutex_lock(&ddev->cmd_lock);

	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
	queue);
	if (!cmd) {
	mutex_unlock(&ddev->cmd_lock);
	return;
	}

	list_del(&cmd->queue);

	mutex_unlock(&ddev->cmd_lock);

	if (!IS_ERR(cmd->resp))
	print_hex_dump_debug("DIGITAL RX: ", DUMP_PREFIX_NONE, 16, 1,
	cmd->resp->data, cmd->resp->len, false);

	cmd->cmd_cb(ddev, cmd->cb_context, cmd->resp);

	kfree(cmd->mdaa_params);
	kfree(cmd);

	schedule_work(&ddev->cmd_work);
	}

	static void digital_send_cmd_complete(struct nfc_digital_dev *ddev,
	void arg, struct sk_buff resp)
	{
	struct digital_cmd *cmd = arg;

	cmd->resp = resp;

	schedule_work(&ddev->cmd_complete_work);
	}

	static void digital_wq_cmd(struct work_struct *work)
	{
	int rc;
	struct digital_cmd *cmd;
	struct digital_tg_mdaa_params *params;
	struct nfc_digital_dev *ddev = container_of(work,
	struct nfc_digital_dev,
	cmd_work);

	mutex_lock(&ddev->cmd_lock);

	cmd = list_first_entry_or_null(&ddev->cmd_queue, struct digital_cmd,
	queue);
	if (!cmd \|\| cmd->pending) {
	mutex_unlock(&ddev->cmd_lock);
	return;
	}

	mutex_unlock(&ddev->cmd_lock);

	if (cmd->req)
	print_hex_dump_debug("DIGITAL TX: ", DUMP_PREFIX_NONE, 16, 1,
	cmd->req->data, cmd->req->len, false);

	switch (cmd->type) {
	case DIGITAL_CMD_IN_SEND:
	rc = ddev->ops->in_send_cmd(ddev, cmd->req, cmd->timeout,
	digital_send_cmd_complete, cmd);
	break;

	case DIGITAL_CMD_TG_SEND:
	rc = ddev->ops->tg_send_cmd(ddev, cmd->req, cmd->timeout,
	digital_send_cmd_complete, cmd);
	break;

	case DIGITAL_CMD_TG_LISTEN:
	rc = ddev->ops->tg_listen(ddev, cmd->timeout,
	digital_send_cmd_complete, cmd);
	break;

	case DIGITAL_CMD_TG_LISTEN_MDAA:
	params = cmd->mdaa_params;

	rc = ddev->ops->tg_listen_mdaa(ddev, params, cmd->timeout,
	digital_send_cmd_complete, cmd);
	break;

	default:
	pr_err("Unknown cmd type %d\n", cmd->type);
	return;
	}

	if (!rc)
	return;

	pr_err("in_send_command returned err %d\n", rc);

	mutex_lock(&ddev->cmd_lock);
	list_del(&cmd->queue);
	mutex_unlock(&ddev->cmd_lock);

	kfree_skb(cmd->req);
	kfree(cmd->mdaa_params);
	kfree(cmd);

	schedule_work(&ddev->cmd_work);
	}

	int digital_send_cmd(struct nfc_digital_dev *ddev, u8 cmd_type,
	struct sk_buff skb, struct digital_tg_mdaa_params params,
	u16 timeout, nfc_digital_cmd_complete_t cmd_cb,
	void *cb_context)
	{
	struct digital_cmd *cmd;

	cmd = kzalloc(sizeof(struct digital_cmd), GFP_KERNEL);
	if (!cmd)
	return -ENOMEM;

	cmd->type = cmd_type;
	cmd->timeout = timeout;
	cmd->req = skb;
	cmd->mdaa_params = params;
	cmd->cmd_cb = cmd_cb;
	cmd->cb_context = cb_context;
	INIT_LIST_HEAD(&cmd->queue);

	mutex_lock(&ddev->cmd_lock);
	list_add_tail(&cmd->queue, &ddev->cmd_queue);
	mutex_unlock(&ddev->cmd_lock);

	schedule_work(&ddev->cmd_work);

	return 0;
	}

	int digital_in_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
	{
	int rc;

	rc = ddev->ops->in_configure_hw(ddev, type, param);
	if (rc)
	pr_err("in_configure_hw failed: %d\n", rc);

	return rc;
	}

	int digital_tg_configure_hw(struct nfc_digital_dev *ddev, int type, int param)
	{
	int rc;

	rc = ddev->ops->tg_configure_hw(ddev, type, param);
	if (rc)
	pr_err("tg_configure_hw failed: %d\n", rc);

	return rc;
	}

	static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
	{
	struct digital_tg_mdaa_params *params;

	params = kzalloc(sizeof(struct digital_tg_mdaa_params), GFP_KERNEL);
	if (!params)
	return -ENOMEM;

	params->sens_res = DIGITAL_SENS_RES_NFC_DEP;
	get_random_bytes(params->nfcid1, sizeof(params->nfcid1));
	params->sel_res = DIGITAL_SEL_RES_NFC_DEP;

	params->nfcid2[0] = DIGITAL_SENSF_NFCID2_NFC_DEP_B1;
	params->nfcid2[1] = DIGITAL_SENSF_NFCID2_NFC_DEP_B2;
	get_random_bytes(params->nfcid2 + 2, NFC_NFCID2_MAXSIZE - 2);
	params->sc = DIGITAL_SENSF_FELICA_SC;

	return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MDAA, NULL, params,
	500, digital_tg_recv_atr_req, NULL);
	}

	int digital_target_found(struct nfc_digital_dev *ddev,
	struct nfc_target *target, u8 protocol)
	{
	int rc;
	u8 framing;
	u8 rf_tech;
	int (check_crc)(struct sk_buff skb);
	void (add_crc)(struct sk_buff skb);

	rf_tech = ddev->poll_techs[ddev->poll_tech_index].rf_tech;

	switch (protocol) {
	case NFC_PROTO_JEWEL:
	framing = NFC_DIGITAL_FRAMING_NFCA_T1T;
	check_crc = digital_skb_check_crc_b;
	add_crc = digital_skb_add_crc_b;
	break;

	case NFC_PROTO_MIFARE:
	framing = NFC_DIGITAL_FRAMING_NFCA_T2T;
	check_crc = digital_skb_check_crc_a;
	add_crc = digital_skb_add_crc_a;
	break;

	case NFC_PROTO_FELICA:
	framing = NFC_DIGITAL_FRAMING_NFCF_T3T;
	check_crc = digital_skb_check_crc_f;
	add_crc = digital_skb_add_crc_f;
	break;

	case NFC_PROTO_NFC_DEP:
	if (rf_tech == NFC_DIGITAL_RF_TECH_106A) {
	framing = NFC_DIGITAL_FRAMING_NFCA_NFC_DEP;
	check_crc = digital_skb_check_crc_a;
	add_crc = digital_skb_add_crc_a;
	} else {
	framing = NFC_DIGITAL_FRAMING_NFCF_NFC_DEP;
	check_crc = digital_skb_check_crc_f;
	add_crc = digital_skb_add_crc_f;
	}
	break;

	case NFC_PROTO_ISO15693:
	framing = NFC_DIGITAL_FRAMING_ISO15693_T5T;
	check_crc = digital_skb_check_crc_b;
	add_crc = digital_skb_add_crc_b;
	break;

	case NFC_PROTO_ISO14443:
	framing = NFC_DIGITAL_FRAMING_NFCA_T4T;
	check_crc = digital_skb_check_crc_a;
	add_crc = digital_skb_add_crc_a;
	break;

	default:
	pr_err("Invalid protocol %d\n", protocol);
	return -EINVAL;
	}

	pr_debug("rf_tech=%d, protocol=%d\n", rf_tech, protocol);

	ddev->curr_rf_tech = rf_tech;

	if (DIGITAL_DRV_CAPS_IN_CRC(ddev)) {
	ddev->skb_add_crc = digital_skb_add_crc_none;
	ddev->skb_check_crc = digital_skb_check_crc_none;
	} else {
	ddev->skb_add_crc = add_crc;
	ddev->skb_check_crc = check_crc;
	}

	rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING, framing);
	if (rc)
	return rc;

	target->supported_protocols = (1 << protocol);
	rc = nfc_targets_found(ddev->nfc_dev, target, 1);
	if (rc)
	return rc;

	ddev->poll_tech_count = 0;

	return 0;
	}

	void digital_poll_next_tech(struct nfc_digital_dev *ddev)
	{
	digital_switch_rf(ddev, 0);

	mutex_lock(&ddev->poll_lock);

	if (!ddev->poll_tech_count) {
	mutex_unlock(&ddev->poll_lock);
	return;
	}

	ddev->poll_tech_index = (ddev->poll_tech_index + 1) %
	ddev->poll_tech_count;

	mutex_unlock(&ddev->poll_lock);

	schedule_work(&ddev->poll_work);
	}

	static void digital_wq_poll(struct work_struct *work)
	{
	int rc;
	struct digital_poll_tech *poll_tech;
	struct nfc_digital_dev *ddev = container_of(work,
	struct nfc_digital_dev,
	poll_work);
	mutex_lock(&ddev->poll_lock);

	if (!ddev->poll_tech_count) {
	mutex_unlock(&ddev->poll_lock);
	return;
	}

	poll_tech = &ddev->poll_techs[ddev->poll_tech_index];

	mutex_unlock(&ddev->poll_lock);

	rc = poll_tech->poll_func(ddev, poll_tech->rf_tech);
	if (rc)
	digital_poll_next_tech(ddev);
	}

	static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
	digital_poll_t poll_func)
	{
	struct digital_poll_tech *poll_tech;

	if (ddev->poll_tech_count >= NFC_DIGITAL_POLL_MODE_COUNT_MAX)
	return;

	poll_tech = &ddev->poll_techs[ddev->poll_tech_count++];

	poll_tech->rf_tech = rf_tech;
	poll_tech->poll_func = poll_func;
	}

	/**
	* start_poll operation
	*
	* For every supported protocol, the corresponding polling function is added
	* to the table of polling technologies (ddev->poll_techs[]) using
	* digital_add_poll_tech().
	* When a polling function fails (by timeout or protocol error) the next one is
	* schedule by digital_poll_next_tech() on the poll workqueue (ddev->poll_work).
	*/
	static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
	__u32 tm_protocols)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
	u32 matching_im_protocols, matching_tm_protocols;

	pr_debug("protocols: im 0x%x, tm 0x%x, supported 0x%x\n", im_protocols,
	tm_protocols, ddev->protocols);

	matching_im_protocols = ddev->protocols & im_protocols;
	matching_tm_protocols = ddev->protocols & tm_protocols;

	if (!matching_im_protocols && !matching_tm_protocols) {
	pr_err("Unknown protocol\n");
	return -EINVAL;
	}

	if (ddev->poll_tech_count) {
	pr_err("Already polling\n");
	return -EBUSY;
	}

	if (ddev->curr_protocol) {
	pr_err("A target is already active\n");
	return -EBUSY;
	}

	ddev->poll_tech_count = 0;
	ddev->poll_tech_index = 0;

	if (matching_im_protocols & DIGITAL_PROTO_NFCA_RF_TECH)
	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
	digital_in_send_sens_req);

	if (matching_im_protocols & DIGITAL_PROTO_NFCF_RF_TECH) {
	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
	digital_in_send_sensf_req);

	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
	digital_in_send_sensf_req);
	}

	if (matching_im_protocols & DIGITAL_PROTO_ISO15693_RF_TECH)
	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_ISO15693,
	digital_in_send_iso15693_inv_req);

	if (matching_tm_protocols & NFC_PROTO_NFC_DEP_MASK) {
	if (ddev->ops->tg_listen_mdaa) {
	digital_add_poll_tech(ddev, 0,
	digital_tg_listen_mdaa);
	} else {
	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
	digital_tg_listen_nfca);

	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_212F,
	digital_tg_listen_nfcf);

	digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_424F,
	digital_tg_listen_nfcf);
	}
	}

	if (!ddev->poll_tech_count) {
	pr_err("Unsupported protocols: im=0x%x, tm=0x%x\n",
	matching_im_protocols, matching_tm_protocols);
	return -EINVAL;
	}

	schedule_work(&ddev->poll_work);

	return 0;
	}

	static void digital_stop_poll(struct nfc_dev *nfc_dev)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	mutex_lock(&ddev->poll_lock);

	if (!ddev->poll_tech_count) {
	pr_err("Polling operation was not running\n");
	mutex_unlock(&ddev->poll_lock);
	return;
	}

	ddev->poll_tech_count = 0;

	mutex_unlock(&ddev->poll_lock);

	cancel_work_sync(&ddev->poll_work);

	digital_abort_cmd(ddev);
	}

	static int digital_dev_up(struct nfc_dev *nfc_dev)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	digital_switch_rf(ddev, 1);

	return 0;
	}

	static int digital_dev_down(struct nfc_dev *nfc_dev)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	digital_switch_rf(ddev, 0);

	return 0;
	}

	static int digital_dep_link_up(struct nfc_dev *nfc_dev,
	struct nfc_target *target,
	__u8 comm_mode, __u8 *gb, size_t gb_len)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
	int rc;

	rc = digital_in_send_atr_req(ddev, target, comm_mode, gb, gb_len);

	if (!rc)
	ddev->curr_protocol = NFC_PROTO_NFC_DEP;

	return rc;
	}

	static int digital_dep_link_down(struct nfc_dev *nfc_dev)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	ddev->curr_protocol = 0;

	return 0;
	}

	static int digital_activate_target(struct nfc_dev *nfc_dev,
	struct nfc_target *target, __u32 protocol)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	if (ddev->poll_tech_count) {
	pr_err("Can't activate a target while polling\n");
	return -EBUSY;
	}

	if (ddev->curr_protocol) {
	pr_err("A target is already active\n");
	return -EBUSY;
	}

	ddev->curr_protocol = protocol;

	return 0;
	}

	static void digital_deactivate_target(struct nfc_dev *nfc_dev,
	struct nfc_target *target)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);

	if (!ddev->curr_protocol) {
	pr_err("No active target\n");
	return;
	}

	ddev->curr_protocol = 0;
	}

	static int digital_tg_send(struct nfc_dev dev, struct sk_buff skb)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(dev);

	return digital_tg_send_dep_res(ddev, skb);
	}

	static void digital_in_send_complete(struct nfc_digital_dev ddev, void arg,
	struct sk_buff *resp)
	{
	struct digital_data_exch *data_exch = arg;
	int rc;

	if (IS_ERR(resp)) {
	rc = PTR_ERR(resp);
	resp = NULL;
	goto done;
	}

	if (ddev->curr_protocol == NFC_PROTO_MIFARE) {
	rc = digital_in_recv_mifare_res(resp);
	/* crc check is done in digital_in_recv_mifare_res() */
	goto done;
	}

	if (ddev->curr_protocol == NFC_PROTO_ISO14443) {
	rc = digital_in_iso_dep_pull_sod(ddev, resp);
	if (rc)
	goto done;
	}

	rc = ddev->skb_check_crc(resp);

	done:
	if (rc) {
	kfree_skb(resp);
	resp = NULL;
	}

	data_exch->cb(data_exch->cb_context, resp, rc);

	kfree(data_exch);
	}

	static int digital_in_send(struct nfc_dev nfc_dev, struct nfc_target target,
	struct sk_buff *skb, data_exchange_cb_t cb,
	void *cb_context)
	{
	struct nfc_digital_dev *ddev = nfc_get_drvdata(nfc_dev);
	struct digital_data_exch *data_exch;
	int rc;

	data_exch = kzalloc(sizeof(struct digital_data_exch), GFP_KERNEL);
	if (!data_exch) {
	pr_err("Failed to allocate data_exch struct\n");
	return -ENOMEM;
	}

	data_exch->cb = cb;
	data_exch->cb_context = cb_context;

	if (ddev->curr_protocol == NFC_PROTO_NFC_DEP) {
	rc = digital_in_send_dep_req(ddev, target, skb, data_exch);
	goto exit;
	}

	if (ddev->curr_protocol == NFC_PROTO_ISO14443) {
	rc = digital_in_iso_dep_push_sod(ddev, skb);
	if (rc)
	goto exit;
	}

	ddev->skb_add_crc(skb);

	rc = digital_in_send_cmd(ddev, skb, 500, digital_in_send_complete,
	data_exch);

	exit:
	if (rc)
	kfree(data_exch);

	return rc;
	}

	static struct nfc_ops digital_nfc_ops = {
	.dev_up = digital_dev_up,
	.dev_down = digital_dev_down,
	.start_poll = digital_start_poll,
	.stop_poll = digital_stop_poll,
	.dep_link_up = digital_dep_link_up,
	.dep_link_down = digital_dep_link_down,
	.activate_target = digital_activate_target,
	.deactivate_target = digital_deactivate_target,
	.tm_send = digital_tg_send,
	.im_transceive = digital_in_send,
	};

	struct nfc_digital_dev nfc_digital_allocate_device(struct nfc_digital_ops ops,
	__u32 supported_protocols,
	__u32 driver_capabilities,
	int tx_headroom, int tx_tailroom)
	{
	struct nfc_digital_dev *ddev;

	if (!ops->in_configure_hw \|\| !ops->in_send_cmd \|\| !ops->tg_listen \|\|
	!ops->tg_configure_hw \|\| !ops->tg_send_cmd \|\| !ops->abort_cmd \|\|
	!ops->switch_rf)
	return NULL;

	ddev = kzalloc(sizeof(struct nfc_digital_dev), GFP_KERNEL);
	if (!ddev)
	return NULL;

	ddev->driver_capabilities = driver_capabilities;
	ddev->ops = ops;

	mutex_init(&ddev->cmd_lock);
	INIT_LIST_HEAD(&ddev->cmd_queue);

	INIT_WORK(&ddev->cmd_work, digital_wq_cmd);
	INIT_WORK(&ddev->cmd_complete_work, digital_wq_cmd_complete);

	mutex_init(&ddev->poll_lock);
	INIT_WORK(&ddev->poll_work, digital_wq_poll);

	if (supported_protocols & NFC_PROTO_JEWEL_MASK)
	ddev->protocols \|= NFC_PROTO_JEWEL_MASK;
	if (supported_protocols & NFC_PROTO_MIFARE_MASK)
	ddev->protocols \|= NFC_PROTO_MIFARE_MASK;
	if (supported_protocols & NFC_PROTO_FELICA_MASK)
	ddev->protocols \|= NFC_PROTO_FELICA_MASK;
	if (supported_protocols & NFC_PROTO_NFC_DEP_MASK)
	ddev->protocols \|= NFC_PROTO_NFC_DEP_MASK;
	if (supported_protocols & NFC_PROTO_ISO15693_MASK)
	ddev->protocols \|= NFC_PROTO_ISO15693_MASK;
	if (supported_protocols & NFC_PROTO_ISO14443_MASK)
	ddev->protocols \|= NFC_PROTO_ISO14443_MASK;

	ddev->tx_headroom = tx_headroom + DIGITAL_MAX_HEADER_LEN;
	ddev->tx_tailroom = tx_tailroom + DIGITAL_CRC_LEN;

	ddev->nfc_dev = nfc_allocate_device(&digital_nfc_ops, ddev->protocols,
	ddev->tx_headroom,
	ddev->tx_tailroom);
	if (!ddev->nfc_dev) {
	pr_err("nfc_allocate_device failed\n");
	goto free_dev;
	}

	nfc_set_drvdata(ddev->nfc_dev, ddev);

	return ddev;

	free_dev:
	kfree(ddev);

	return NULL;
	}
	EXPORT_SYMBOL(nfc_digital_allocate_device);

	void nfc_digital_free_device(struct nfc_digital_dev *ddev)
	{
	nfc_free_device(ddev->nfc_dev);
	kfree(ddev);
	}
	EXPORT_SYMBOL(nfc_digital_free_device);

	int nfc_digital_register_device(struct nfc_digital_dev *ddev)
	{
	return nfc_register_device(ddev->nfc_dev);
	}
	EXPORT_SYMBOL(nfc_digital_register_device);

	void nfc_digital_unregister_device(struct nfc_digital_dev *ddev)
	{
	struct digital_cmd cmd, n;

	nfc_unregister_device(ddev->nfc_dev);

	mutex_lock(&ddev->poll_lock);
	ddev->poll_tech_count = 0;
	mutex_unlock(&ddev->poll_lock);

	cancel_work_sync(&ddev->poll_work);
	cancel_work_sync(&ddev->cmd_work);
	cancel_work_sync(&ddev->cmd_complete_work);

	list_for_each_entry_safe(cmd, n, &ddev->cmd_queue, queue) {
	list_del(&cmd->queue);
	kfree(cmd->mdaa_params);
	kfree(cmd);
	}
	}
	EXPORT_SYMBOL(nfc_digital_unregister_device);

	MODULE_LICENSE("GPL");