Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 793 insertions, 0 deletions

diff --git a/net/nfc/nci/hci.c b/net/nfc/nci/hci.c
new file mode 100644
index 0000000000..de175318a3
--- /dev/null
+++ b/net/nfc/nci/hci.c
@@ -0,0 +1,793 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  The NFC Controller Interface is the communication protocol between an
+ *  NFC Controller (NFCC) and a Device Host (DH).
+ *  This is the HCI over NCI implementation, as specified in the 10.2
+ *  section of the NCI 1.1 specification.
+ *
+ *  Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
+ */
+
+#include <linux/skbuff.h>
+
+#include "../nfc.h"
+#include <net/nfc/nci.h>
+#include <net/nfc/nci_core.h>
+#include <linux/nfc.h>
+#include <linux/kcov.h>
+
+struct nci_data {
+	u8 conn_id;
+	u8 pipe;
+	u8 cmd;
+	const u8 *data;
+	u32 data_len;
+} __packed;
+
+struct nci_hci_create_pipe_params {
+	u8 src_gate;
+	u8 dest_host;
+	u8 dest_gate;
+} __packed;
+
+struct nci_hci_create_pipe_resp {
+	u8 src_host;
+	u8 src_gate;
+	u8 dest_host;
+	u8 dest_gate;
+	u8 pipe;
+} __packed;
+
+struct nci_hci_delete_pipe_noti {
+	u8 pipe;
+} __packed;
+
+struct nci_hci_all_pipe_cleared_noti {
+	u8 host;
+} __packed;
+
+struct nci_hcp_message {
+	u8 header;      /* type -cmd,evt,rsp- + instruction */
+	u8 data[];
+} __packed;
+
+struct nci_hcp_packet {
+	u8 header;      /* cbit+pipe */
+	struct nci_hcp_message message;
+} __packed;
+
+#define NCI_HCI_ANY_SET_PARAMETER  0x01
+#define NCI_HCI_ANY_GET_PARAMETER  0x02
+#define NCI_HCI_ANY_CLOSE_PIPE     0x04
+#define NCI_HCI_ADM_CLEAR_ALL_PIPE 0x14
+
+#define NCI_HFP_NO_CHAINING        0x80
+
+#define NCI_NFCEE_ID_HCI                0x80
+
+#define NCI_EVT_HOT_PLUG           0x03
+
+#define NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY       0x01
+#define NCI_HCI_ADM_CREATE_PIPE			0x10
+#define NCI_HCI_ADM_DELETE_PIPE			0x11
+
+/* HCP headers */
+#define NCI_HCI_HCP_PACKET_HEADER_LEN      1
+#define NCI_HCI_HCP_MESSAGE_HEADER_LEN     1
+#define NCI_HCI_HCP_HEADER_LEN             2
+
+/* HCP types */
+#define NCI_HCI_HCP_COMMAND        0x00
+#define NCI_HCI_HCP_EVENT          0x01
+#define NCI_HCI_HCP_RESPONSE       0x02
+
+#define NCI_HCI_ADM_NOTIFY_PIPE_CREATED     0x12
+#define NCI_HCI_ADM_NOTIFY_PIPE_DELETED     0x13
+#define NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED 0x15
+
+#define NCI_HCI_FRAGMENT           0x7f
+#define NCI_HCP_HEADER(type, instr) ((((type) & 0x03) << 6) |\
+				      ((instr) & 0x3f))
+
+#define NCI_HCP_MSG_GET_TYPE(header) ((header & 0xc0) >> 6)
+#define NCI_HCP_MSG_GET_CMD(header)  (header & 0x3f)
+#define NCI_HCP_MSG_GET_PIPE(header) (header & 0x7f)
+
+static int nci_hci_result_to_errno(u8 result)
+{
+	switch (result) {
+	case NCI_HCI_ANY_OK:
+		return 0;
+	case NCI_HCI_ANY_E_REG_PAR_UNKNOWN:
+		return -EOPNOTSUPP;
+	case NCI_HCI_ANY_E_TIMEOUT:
+		return -ETIME;
+	default:
+		return -1;
+	}
+}
+
+/* HCI core */
+static void nci_hci_reset_pipes(struct nci_hci_dev *hdev)
+{
+	int i;
+
+	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
+		hdev->pipes[i].gate = NCI_HCI_INVALID_GATE;
+		hdev->pipes[i].host = NCI_HCI_INVALID_HOST;
+	}
+	memset(hdev->gate2pipe, NCI_HCI_INVALID_PIPE, sizeof(hdev->gate2pipe));
+}
+
+static void nci_hci_reset_pipes_per_host(struct nci_dev *ndev, u8 host)
+{
+	int i;
+
+	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
+		if (ndev->hci_dev->pipes[i].host == host) {
+			ndev->hci_dev->pipes[i].gate = NCI_HCI_INVALID_GATE;
+			ndev->hci_dev->pipes[i].host = NCI_HCI_INVALID_HOST;
+		}
+	}
+}
+
+/* Fragment HCI data over NCI packet.
+ * NFC Forum NCI 10.2.2 Data Exchange:
+ * The payload of the Data Packets sent on the Logical Connection SHALL be
+ * valid HCP packets, as defined within [ETSI_102622]. Each Data Packet SHALL
+ * contain a single HCP packet. NCI Segmentation and Reassembly SHALL NOT be
+ * applied to Data Messages in either direction. The HCI fragmentation mechanism
+ * is used if required.
+ */
+static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
+			     const u8 data_type, const u8 *data,
+			     size_t data_len)
+{
+	const struct nci_conn_info *conn_info;
+	struct sk_buff *skb;
+	int len, i, r;
+	u8 cb = pipe;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	i = 0;
+	skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len +
+			    NCI_DATA_HDR_SIZE, GFP_ATOMIC);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_reserve(skb, NCI_DATA_HDR_SIZE + 2);
+	*(u8 *)skb_push(skb, 1) = data_type;
+
+	do {
+		/* If last packet add NCI_HFP_NO_CHAINING */
+		if (i + conn_info->max_pkt_payload_len -
+		    (skb->len + 1) >= data_len) {
+			cb |= NCI_HFP_NO_CHAINING;
+			len = data_len - i;
+		} else {
+			len = conn_info->max_pkt_payload_len - skb->len - 1;
+		}
+
+		*(u8 *)skb_push(skb, 1) = cb;
+
+		if (len > 0)
+			skb_put_data(skb, data + i, len);
+
+		r = nci_send_data(ndev, conn_info->conn_id, skb);
+		if (r < 0)
+			return r;
+
+		i += len;
+
+		if (i < data_len) {
+			skb = nci_skb_alloc(ndev,
+					    conn_info->max_pkt_payload_len +
+					    NCI_DATA_HDR_SIZE, GFP_ATOMIC);
+			if (!skb)
+				return -ENOMEM;
+
+			skb_reserve(skb, NCI_DATA_HDR_SIZE + 1);
+		}
+	} while (i < data_len);
+
+	return i;
+}
+
+static void nci_hci_send_data_req(struct nci_dev *ndev, const void *opt)
+{
+	const struct nci_data *data = opt;
+
+	nci_hci_send_data(ndev, data->pipe, data->cmd,
+			  data->data, data->data_len);
+}
+
+int nci_hci_send_event(struct nci_dev *ndev, u8 gate, u8 event,
+		       const u8 *param, size_t param_len)
+{
+	u8 pipe = ndev->hci_dev->gate2pipe[gate];
+
+	if (pipe == NCI_HCI_INVALID_PIPE)
+		return -EADDRNOTAVAIL;
+
+	return nci_hci_send_data(ndev, pipe,
+			NCI_HCP_HEADER(NCI_HCI_HCP_EVENT, event),
+			param, param_len);
+}
+EXPORT_SYMBOL(nci_hci_send_event);
+
+int nci_hci_send_cmd(struct nci_dev *ndev, u8 gate, u8 cmd,
+		     const u8 *param, size_t param_len,
+		     struct sk_buff **skb)
+{
+	const struct nci_hcp_message *message;
+	const struct nci_conn_info *conn_info;
+	struct nci_data data;
+	int r;
+	u8 pipe = ndev->hci_dev->gate2pipe[gate];
+
+	if (pipe == NCI_HCI_INVALID_PIPE)
+		return -EADDRNOTAVAIL;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	data.conn_id = conn_info->conn_id;
+	data.pipe = pipe;
+	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND, cmd);
+	data.data = param;
+	data.data_len = param_len;
+
+	r = nci_request(ndev, nci_hci_send_data_req, &data,
+			msecs_to_jiffies(NCI_DATA_TIMEOUT));
+	if (r == NCI_STATUS_OK) {
+		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
+		r = nci_hci_result_to_errno(
+			NCI_HCP_MSG_GET_CMD(message->header));
+		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
+
+		if (!r && skb)
+			*skb = conn_info->rx_skb;
+	}
+
+	return r;
+}
+EXPORT_SYMBOL(nci_hci_send_cmd);
+
+int nci_hci_clear_all_pipes(struct nci_dev *ndev)
+{
+	int r;
+
+	r = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
+			     NCI_HCI_ADM_CLEAR_ALL_PIPE, NULL, 0, NULL);
+	if (r < 0)
+		return r;
+
+	nci_hci_reset_pipes(ndev->hci_dev);
+	return r;
+}
+EXPORT_SYMBOL(nci_hci_clear_all_pipes);
+
+static void nci_hci_event_received(struct nci_dev *ndev, u8 pipe,
+				   u8 event, struct sk_buff *skb)
+{
+	if (ndev->ops->hci_event_received)
+		ndev->ops->hci_event_received(ndev, pipe, event, skb);
+}
+
+static void nci_hci_cmd_received(struct nci_dev *ndev, u8 pipe,
+				 u8 cmd, struct sk_buff *skb)
+{
+	u8 gate = ndev->hci_dev->pipes[pipe].gate;
+	u8 status = NCI_HCI_ANY_OK | ~NCI_HCI_FRAGMENT;
+	u8 dest_gate, new_pipe;
+	struct nci_hci_create_pipe_resp *create_info;
+	struct nci_hci_delete_pipe_noti *delete_info;
+	struct nci_hci_all_pipe_cleared_noti *cleared_info;
+
+	pr_debug("from gate %x pipe %x cmd %x\n", gate, pipe, cmd);
+
+	switch (cmd) {
+	case NCI_HCI_ADM_NOTIFY_PIPE_CREATED:
+		if (skb->len != 5) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+		create_info = (struct nci_hci_create_pipe_resp *)skb->data;
+		dest_gate = create_info->dest_gate;
+		new_pipe = create_info->pipe;
+		if (new_pipe >= NCI_HCI_MAX_PIPES) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+
+		/* Save the new created pipe and bind with local gate,
+		 * the description for skb->data[3] is destination gate id
+		 * but since we received this cmd from host controller, we
+		 * are the destination and it is our local gate
+		 */
+		ndev->hci_dev->gate2pipe[dest_gate] = new_pipe;
+		ndev->hci_dev->pipes[new_pipe].gate = dest_gate;
+		ndev->hci_dev->pipes[new_pipe].host =
+						create_info->src_host;
+		break;
+	case NCI_HCI_ANY_OPEN_PIPE:
+		/* If the pipe is not created report an error */
+		if (gate == NCI_HCI_INVALID_GATE) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+		break;
+	case NCI_HCI_ADM_NOTIFY_PIPE_DELETED:
+		if (skb->len != 1) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+		delete_info = (struct nci_hci_delete_pipe_noti *)skb->data;
+		if (delete_info->pipe >= NCI_HCI_MAX_PIPES) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+
+		ndev->hci_dev->pipes[delete_info->pipe].gate =
+						NCI_HCI_INVALID_GATE;
+		ndev->hci_dev->pipes[delete_info->pipe].host =
+						NCI_HCI_INVALID_HOST;
+		break;
+	case NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED:
+		if (skb->len != 1) {
+			status = NCI_HCI_ANY_E_NOK;
+			goto exit;
+		}
+
+		cleared_info =
+			(struct nci_hci_all_pipe_cleared_noti *)skb->data;
+		nci_hci_reset_pipes_per_host(ndev, cleared_info->host);
+		break;
+	default:
+		pr_debug("Discarded unknown cmd %x to gate %x\n", cmd, gate);
+		break;
+	}
+
+	if (ndev->ops->hci_cmd_received)
+		ndev->ops->hci_cmd_received(ndev, pipe, cmd, skb);
+
+exit:
+	nci_hci_send_data(ndev, pipe, status, NULL, 0);
+
+	kfree_skb(skb);
+}
+
+static void nci_hci_resp_received(struct nci_dev *ndev, u8 pipe,
+				  struct sk_buff *skb)
+{
+	struct nci_conn_info *conn_info;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		goto exit;
+
+	conn_info->rx_skb = skb;
+
+exit:
+	nci_req_complete(ndev, NCI_STATUS_OK);
+}
+
+/* Receive hcp message for pipe, with type and cmd.
+ * skb contains optional message data only.
+ */
+static void nci_hci_hcp_message_rx(struct nci_dev *ndev, u8 pipe,
+				   u8 type, u8 instruction, struct sk_buff *skb)
+{
+	switch (type) {
+	case NCI_HCI_HCP_RESPONSE:
+		nci_hci_resp_received(ndev, pipe, skb);
+		break;
+	case NCI_HCI_HCP_COMMAND:
+		nci_hci_cmd_received(ndev, pipe, instruction, skb);
+		break;
+	case NCI_HCI_HCP_EVENT:
+		nci_hci_event_received(ndev, pipe, instruction, skb);
+		break;
+	default:
+		pr_err("UNKNOWN MSG Type %d, instruction=%d\n",
+		       type, instruction);
+		kfree_skb(skb);
+		break;
+	}
+
+	nci_req_complete(ndev, NCI_STATUS_OK);
+}
+
+static void nci_hci_msg_rx_work(struct work_struct *work)
+{
+	struct nci_hci_dev *hdev =
+		container_of(work, struct nci_hci_dev, msg_rx_work);
+	struct sk_buff *skb;
+	const struct nci_hcp_message *message;
+	u8 pipe, type, instruction;
+
+	for (; (skb = skb_dequeue(&hdev->msg_rx_queue)); kcov_remote_stop()) {
+		kcov_remote_start_common(skb_get_kcov_handle(skb));
+		pipe = NCI_HCP_MSG_GET_PIPE(skb->data[0]);
+		skb_pull(skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
+		message = (struct nci_hcp_message *)skb->data;
+		type = NCI_HCP_MSG_GET_TYPE(message->header);
+		instruction = NCI_HCP_MSG_GET_CMD(message->header);
+		skb_pull(skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
+
+		nci_hci_hcp_message_rx(hdev->ndev, pipe,
+				       type, instruction, skb);
+	}
+}
+
+void nci_hci_data_received_cb(void *context,
+			      struct sk_buff *skb, int err)
+{
+	struct nci_dev *ndev = (struct nci_dev *)context;
+	struct nci_hcp_packet *packet;
+	u8 pipe, type;
+	struct sk_buff *hcp_skb;
+	struct sk_buff *frag_skb;
+	int msg_len;
+
+	if (err) {
+		nci_req_complete(ndev, err);
+		return;
+	}
+
+	packet = (struct nci_hcp_packet *)skb->data;
+	if ((packet->header & ~NCI_HCI_FRAGMENT) == 0) {
+		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
+		return;
+	}
+
+	/* it's the last fragment. Does it need re-aggregation? */
+	if (skb_queue_len(&ndev->hci_dev->rx_hcp_frags)) {
+		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
+		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
+
+		msg_len = 0;
+		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
+			msg_len += (frag_skb->len -
+				    NCI_HCI_HCP_PACKET_HEADER_LEN);
+		}
+
+		hcp_skb = nfc_alloc_recv_skb(NCI_HCI_HCP_PACKET_HEADER_LEN +
+					     msg_len, GFP_KERNEL);
+		if (!hcp_skb) {
+			nci_req_complete(ndev, -ENOMEM);
+			return;
+		}
+
+		skb_put_u8(hcp_skb, pipe);
+
+		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
+			msg_len = frag_skb->len - NCI_HCI_HCP_PACKET_HEADER_LEN;
+			skb_put_data(hcp_skb,
+				     frag_skb->data + NCI_HCI_HCP_PACKET_HEADER_LEN,
+				     msg_len);
+		}
+
+		skb_queue_purge(&ndev->hci_dev->rx_hcp_frags);
+	} else {
+		packet->header &= NCI_HCI_FRAGMENT;
+		hcp_skb = skb;
+	}
+
+	/* if this is a response, dispatch immediately to
+	 * unblock waiting cmd context. Otherwise, enqueue to dispatch
+	 * in separate context where handler can also execute command.
+	 */
+	packet = (struct nci_hcp_packet *)hcp_skb->data;
+	type = NCI_HCP_MSG_GET_TYPE(packet->message.header);
+	if (type == NCI_HCI_HCP_RESPONSE) {
+		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
+		skb_pull(hcp_skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
+		nci_hci_hcp_message_rx(ndev, pipe, type,
+				       NCI_STATUS_OK, hcp_skb);
+	} else {
+		skb_queue_tail(&ndev->hci_dev->msg_rx_queue, hcp_skb);
+		schedule_work(&ndev->hci_dev->msg_rx_work);
+	}
+}
+
+int nci_hci_open_pipe(struct nci_dev *ndev, u8 pipe)
+{
+	struct nci_data data;
+	const struct nci_conn_info *conn_info;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	data.conn_id = conn_info->conn_id;
+	data.pipe = pipe;
+	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
+				       NCI_HCI_ANY_OPEN_PIPE);
+	data.data = NULL;
+	data.data_len = 0;
+
+	return nci_request(ndev, nci_hci_send_data_req, &data,
+			   msecs_to_jiffies(NCI_DATA_TIMEOUT));
+}
+EXPORT_SYMBOL(nci_hci_open_pipe);
+
+static u8 nci_hci_create_pipe(struct nci_dev *ndev, u8 dest_host,
+			      u8 dest_gate, int *result)
+{
+	u8 pipe;
+	struct sk_buff *skb;
+	struct nci_hci_create_pipe_params params;
+	const struct nci_hci_create_pipe_resp *resp;
+
+	pr_debug("gate=%d\n", dest_gate);
+
+	params.src_gate = NCI_HCI_ADMIN_GATE;
+	params.dest_host = dest_host;
+	params.dest_gate = dest_gate;
+
+	*result = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
+				   NCI_HCI_ADM_CREATE_PIPE,
+				   (u8 *)&params, sizeof(params), &skb);
+	if (*result < 0)
+		return NCI_HCI_INVALID_PIPE;
+
+	resp = (struct nci_hci_create_pipe_resp *)skb->data;
+	pipe = resp->pipe;
+	kfree_skb(skb);
+
+	pr_debug("pipe created=%d\n", pipe);
+
+	return pipe;
+}
+
+static int nci_hci_delete_pipe(struct nci_dev *ndev, u8 pipe)
+{
+	return nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
+				NCI_HCI_ADM_DELETE_PIPE, &pipe, 1, NULL);
+}
+
+int nci_hci_set_param(struct nci_dev *ndev, u8 gate, u8 idx,
+		      const u8 *param, size_t param_len)
+{
+	const struct nci_hcp_message *message;
+	const struct nci_conn_info *conn_info;
+	struct nci_data data;
+	int r;
+	u8 *tmp;
+	u8 pipe = ndev->hci_dev->gate2pipe[gate];
+
+	pr_debug("idx=%d to gate %d\n", idx, gate);
+
+	if (pipe == NCI_HCI_INVALID_PIPE)
+		return -EADDRNOTAVAIL;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	tmp = kmalloc(1 + param_len, GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
+
+	*tmp = idx;
+	memcpy(tmp + 1, param, param_len);
+
+	data.conn_id = conn_info->conn_id;
+	data.pipe = pipe;
+	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
+				       NCI_HCI_ANY_SET_PARAMETER);
+	data.data = tmp;
+	data.data_len = param_len + 1;
+
+	r = nci_request(ndev, nci_hci_send_data_req, &data,
+			msecs_to_jiffies(NCI_DATA_TIMEOUT));
+	if (r == NCI_STATUS_OK) {
+		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
+		r = nci_hci_result_to_errno(
+			NCI_HCP_MSG_GET_CMD(message->header));
+		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
+	}
+
+	kfree(tmp);
+	return r;
+}
+EXPORT_SYMBOL(nci_hci_set_param);
+
+int nci_hci_get_param(struct nci_dev *ndev, u8 gate, u8 idx,
+		      struct sk_buff **skb)
+{
+	const struct nci_hcp_message *message;
+	const struct nci_conn_info *conn_info;
+	struct nci_data data;
+	int r;
+	u8 pipe = ndev->hci_dev->gate2pipe[gate];
+
+	pr_debug("idx=%d to gate %d\n", idx, gate);
+
+	if (pipe == NCI_HCI_INVALID_PIPE)
+		return -EADDRNOTAVAIL;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	data.conn_id = conn_info->conn_id;
+	data.pipe = pipe;
+	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
+				  NCI_HCI_ANY_GET_PARAMETER);
+	data.data = &idx;
+	data.data_len = 1;
+
+	r = nci_request(ndev, nci_hci_send_data_req, &data,
+			msecs_to_jiffies(NCI_DATA_TIMEOUT));
+
+	if (r == NCI_STATUS_OK) {
+		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
+		r = nci_hci_result_to_errno(
+			NCI_HCP_MSG_GET_CMD(message->header));
+		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
+
+		if (!r && skb)
+			*skb = conn_info->rx_skb;
+	}
+
+	return r;
+}
+EXPORT_SYMBOL(nci_hci_get_param);
+
+int nci_hci_connect_gate(struct nci_dev *ndev,
+			 u8 dest_host, u8 dest_gate, u8 pipe)
+{
+	bool pipe_created = false;
+	int r;
+
+	if (pipe == NCI_HCI_DO_NOT_OPEN_PIPE)
+		return 0;
+
+	if (ndev->hci_dev->gate2pipe[dest_gate] != NCI_HCI_INVALID_PIPE)
+		return -EADDRINUSE;
+
+	if (pipe != NCI_HCI_INVALID_PIPE)
+		goto open_pipe;
+
+	switch (dest_gate) {
+	case NCI_HCI_LINK_MGMT_GATE:
+		pipe = NCI_HCI_LINK_MGMT_PIPE;
+	break;
+	case NCI_HCI_ADMIN_GATE:
+		pipe = NCI_HCI_ADMIN_PIPE;
+	break;
+	default:
+		pipe = nci_hci_create_pipe(ndev, dest_host, dest_gate, &r);
+		if (pipe == NCI_HCI_INVALID_PIPE)
+			return r;
+		pipe_created = true;
+		break;
+	}
+
+open_pipe:
+	r = nci_hci_open_pipe(ndev, pipe);
+	if (r < 0) {
+		if (pipe_created) {
+			if (nci_hci_delete_pipe(ndev, pipe) < 0) {
+				/* TODO: Cannot clean by deleting pipe...
+				 * -> inconsistent state
+				 */
+			}
+		}
+		return r;
+	}
+
+	ndev->hci_dev->pipes[pipe].gate = dest_gate;
+	ndev->hci_dev->pipes[pipe].host = dest_host;
+	ndev->hci_dev->gate2pipe[dest_gate] = pipe;
+
+	return 0;
+}
+EXPORT_SYMBOL(nci_hci_connect_gate);
+
+static int nci_hci_dev_connect_gates(struct nci_dev *ndev,
+				     u8 gate_count,
+				     const struct nci_hci_gate *gates)
+{
+	int r;
+
+	while (gate_count--) {
+		r = nci_hci_connect_gate(ndev, gates->dest_host,
+					 gates->gate, gates->pipe);
+		if (r < 0)
+			return r;
+		gates++;
+	}
+
+	return 0;
+}
+
+int nci_hci_dev_session_init(struct nci_dev *ndev)
+{
+	struct nci_conn_info *conn_info;
+	struct sk_buff *skb;
+	int r;
+
+	ndev->hci_dev->count_pipes = 0;
+	ndev->hci_dev->expected_pipes = 0;
+
+	conn_info = ndev->hci_dev->conn_info;
+	if (!conn_info)
+		return -EPROTO;
+
+	conn_info->data_exchange_cb = nci_hci_data_received_cb;
+	conn_info->data_exchange_cb_context = ndev;
+
+	nci_hci_reset_pipes(ndev->hci_dev);
+
+	if (ndev->hci_dev->init_data.gates[0].gate != NCI_HCI_ADMIN_GATE)
+		return -EPROTO;
+
+	r = nci_hci_connect_gate(ndev,
+				 ndev->hci_dev->init_data.gates[0].dest_host,
+				 ndev->hci_dev->init_data.gates[0].gate,
+				 ndev->hci_dev->init_data.gates[0].pipe);
+	if (r < 0)
+		return r;
+
+	r = nci_hci_get_param(ndev, NCI_HCI_ADMIN_GATE,
+			      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY, &skb);
+	if (r < 0)
+		return r;
+
+	if (skb->len &&
+	    skb->len == strlen(ndev->hci_dev->init_data.session_id) &&
+	    !memcmp(ndev->hci_dev->init_data.session_id, skb->data, skb->len) &&
+	    ndev->ops->hci_load_session) {
+		/* Restore gate<->pipe table from some proprietary location. */
+		r = ndev->ops->hci_load_session(ndev);
+	} else {
+		r = nci_hci_clear_all_pipes(ndev);
+		if (r < 0)
+			goto exit;
+
+		r = nci_hci_dev_connect_gates(ndev,
+					      ndev->hci_dev->init_data.gate_count,
+					      ndev->hci_dev->init_data.gates);
+		if (r < 0)
+			goto exit;
+
+		r = nci_hci_set_param(ndev, NCI_HCI_ADMIN_GATE,
+				      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY,
+				      ndev->hci_dev->init_data.session_id,
+				      strlen(ndev->hci_dev->init_data.session_id));
+	}
+
+exit:
+	kfree_skb(skb);
+
+	return r;
+}
+EXPORT_SYMBOL(nci_hci_dev_session_init);
+
+struct nci_hci_dev *nci_hci_allocate(struct nci_dev *ndev)
+{
+	struct nci_hci_dev *hdev;
+
+	hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
+	if (!hdev)
+		return NULL;
+
+	skb_queue_head_init(&hdev->rx_hcp_frags);
+	INIT_WORK(&hdev->msg_rx_work, nci_hci_msg_rx_work);
+	skb_queue_head_init(&hdev->msg_rx_queue);
+	hdev->ndev = ndev;
+
+	return hdev;
+}
+
+void nci_hci_deallocate(struct nci_dev *ndev)
+{
+	kfree(ndev->hci_dev);
+}