Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit eb738fe5 authored by Eric Lapuyade's avatar Eric Lapuyade Committed by John W. Linville
Browse files

NFC: SHDLC implementation 



Most NFC HCI chipsets actually use a simplified HDLC link layer to
carry HCI payloads.
This implementation registers itself as an HCI device on behalf of the
NFC driver.

Signed-off-by: default avatarEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 8b8d2e08

include/net/nfc/shdlc.h

0 → 100644
+104 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2012  Intel Corporation. All rights reserved.

 *

 * 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; either version 2 of the License, or

 * (at your option) any later version.

 *

 * 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.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the

 * Free Software Foundation, Inc.,

 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

 */



#ifndef __NFC_SHDLC_H

#define __NFC_SHDLC_H



struct nfc_shdlc;



struct nfc_shdlc_ops {

	int (*open) (struct nfc_shdlc *shdlc);

	void (*close) (struct nfc_shdlc *shdlc);

	int (*hci_ready) (struct nfc_shdlc *shdlc);

	int (*xmit) (struct nfc_shdlc *shdlc, struct sk_buff *skb);

	int (*start_poll) (struct nfc_shdlc *shdlc, u32 protocols);

	int (*target_from_gate) (struct nfc_shdlc *shdlc, u8 gate,

				 struct nfc_target *target);

	int (*complete_target_discovered) (struct nfc_shdlc *shdlc, u8 gate,

					   struct nfc_target *target);

	int (*data_exchange) (struct nfc_shdlc *shdlc,

			      struct nfc_target *target,

			      struct sk_buff *skb, struct sk_buff **res_skb);

};



enum shdlc_state {

	SHDLC_DISCONNECTED = 0,

	SHDLC_CONNECTING = 1,

	SHDLC_NEGOCIATING = 2,

	SHDLC_CONNECTED = 3

};



struct nfc_shdlc {

	struct mutex state_mutex;

	enum shdlc_state state;

	int hard_fault;



	struct nfc_hci_dev *hdev;



	wait_queue_head_t *connect_wq;

	int connect_tries;

	int connect_result;

	struct timer_list connect_timer;/* aka T3 in spec 10.6.1 */



	u8 w;				/* window size */

	bool srej_support;



	struct timer_list t1_timer;	/* send ack timeout */

	bool t1_active;



	struct timer_list t2_timer;	/* guard/retransmit timeout */

	bool t2_active;



	int ns;				/* next seq num for send */

	int nr;				/* next expected seq num for receive */

	int dnr;			/* oldest sent unacked seq num */



	struct sk_buff_head rcv_q;



	struct sk_buff_head send_q;

	bool rnr;			/* other side is not ready to receive */



	struct sk_buff_head ack_pending_q;



	struct workqueue_struct *sm_wq;

	struct work_struct sm_work;



	struct nfc_shdlc_ops *ops;



	int client_headroom;

	int client_tailroom;



	void *clientdata;

};



void nfc_shdlc_recv_frame(struct nfc_shdlc *shdlc, struct sk_buff *skb);



struct nfc_shdlc *nfc_shdlc_allocate(struct nfc_shdlc_ops *ops,

				     struct nfc_hci_init_data *init_data,

				     u32 protocols,

				     int tx_headroom, int tx_tailroom,

				     int max_link_payload, const char *devname);



void nfc_shdlc_free(struct nfc_shdlc *shdlc);



void nfc_shdlc_set_clientdata(struct nfc_shdlc *shdlc, void *clientdata);

void *nfc_shdlc_get_clientdata(struct nfc_shdlc *shdlc);

struct nfc_hci_dev *nfc_shdlc_get_hci_dev(struct nfc_shdlc *shdlc);



#endif /* __NFC_SHDLC_H */

net/nfc/hci/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -6,3 +6,11 @@ config NFC_HCI 
	 Say Y here if you want to build support for a kernel NFC HCI

	 implementation. This is mostly needed for devices that only process

	 HCI frames, like for example the NXP pn544.



config NFC_SHDLC

	depends on NFC_HCI

	bool "SHDLC link layer for HCI based NFC drivers"

	default n

	---help---

	  Say yes if you use an NFC HCI driver that requires SHDLC link layer.

	  If unsure, say N here.

net/nfc/hci/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -5,3 +5,4 @@ 
obj-$(CONFIG_NFC_HCI) += hci.o



hci-y			:= core.o hcp.o command.o

hci-$(CONFIG_NFC_SHDLC)	+= shdlc.o

net/nfc/hci/shdlc.c

0 → 100644
+945 −0

File added.

Preview size limit exceeded, changes collapsed.