NFC: add nfc subsystem core

The NFC subsystem core is responsible for providing the device driver interface. It is also responsible for providing an interface to the control operations and data exchange. Signed-off-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org> Signed-off-by: Aloisio Almeida Jr <aloisio.almeida@openbossa.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>

NFC: add nfc subsystem core
The NFC subsystem core is responsible for providing the device driver interface. It is also responsible for providing an interface to the control operations and data exchange. Signed-off-by: Lauro Ramos Venancio <lauro.venancio@openbossa.org> Signed-off-by: Aloisio Almeida Jr <aloisio.almeida@openbossa.org> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Lauro Ramos Venancio · John W. Linville
1 parent 2b4562dfd6
Showing 11 changed files with 609 additions and 15 deletions Side-by-side Diff
drivers/Kconfig
drivers/Makefile
drivers/nfc/Kconfig
drivers/nfc/Makefile
include/net/nfc.h
net/Kconfig
net/Makefile
net/nfc/Kconfig
net/nfc/Makefile
net/nfc/core.c
net/nfc/nfc.h
@@ -92,8 +92,6 @@
  
 source "drivers/leds/Kconfig"
  
-source "drivers/nfc/Kconfig"
-
 source "drivers/accessibility/Kconfig"
  
 source "drivers/infiniband/Kconfig"
@@ -120,4 +120,5 @@
 obj-y				+= clk/
  
 obj-$(CONFIG_HWSPINLOCK)	+= hwspinlock/
+obj-$(CONFIG_NFC)		+= nfc/
@@ -2,18 +2,9 @@
 # Near Field Communication (NFC) devices
 #
  
-menuconfig NFC_DEVICES
-	bool "Near Field Communication (NFC) devices"
-	default n
-	---help---
-	  You'll have to say Y if your computer contains an NFC device that
-	  you want to use under Linux.
+menu "Near Field Communication (NFC) devices"
+	depends on NFC
  
-	  You can say N here if you don't have any Near Field Communication
-	  devices connected to your computer.
-
-if NFC_DEVICES
-
 config PN544_NFC
 	tristate "PN544 NFC driver"
 	depends on I2C
@@ -26,6 +17,5 @@
 	  To compile this driver as a module, choose m here. The module will
 	  be called pn544.
  
-
-endif # NFC_DEVICES
+endmenu
@@ -3,4 +3,6 @@
 #
  
 obj-$(CONFIG_PN544_NFC)		+= pn544.o
+
+ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
+ *
+ * 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 __NET_NFC_H
+#define __NET_NFC_H
+
+#include <linux/device.h>
+#include <linux/skbuff.h>
+
+#define nfc_dev_info(dev, fmt, arg...) dev_info((dev), "NFC: " fmt "\n", ## arg)
+#define nfc_dev_err(dev, fmt, arg...) dev_err((dev), "NFC: " fmt "\n", ## arg)
+#define nfc_dev_dbg(dev, fmt, arg...) dev_dbg((dev), fmt "\n", ## arg)
+
+struct nfc_dev;
+
+/**
+ * data_exchange_cb_t - Definition of nfc_data_exchange callback
+ *
+ * @context: nfc_data_exchange cb_context parameter
+ * @skb: response data
+ * @err: If an error has occurred during data exchange, it is the
+ *	error number. Zero means no error.
+ *
+ * When a rx or tx package is lost or corrupted or the target gets out
+ * of the operating field, err is -EIO.
+ */
+typedef void (*data_exchange_cb_t)(void *context, struct sk_buff *skb,
+								int err);
+
+struct nfc_ops {
+	int (*start_poll)(struct nfc_dev *dev, u32 protocols);
+	void (*stop_poll)(struct nfc_dev *dev);
+	int (*activate_target)(struct nfc_dev *dev, u32 target_idx,
+							u32 protocol);
+	void (*deactivate_target)(struct nfc_dev *dev, u32 target_idx);
+	int (*data_exchange)(struct nfc_dev *dev, u32 target_idx,
+				struct sk_buff *skb, data_exchange_cb_t cb,
+							void *cb_context);
+};
+
+struct nfc_dev {
+	unsigned idx;
+	struct device dev;
+	bool polling;
+	u32 supported_protocols;
+
+	struct nfc_ops *ops;
+};
+#define to_nfc_dev(_dev) container_of(_dev, struct nfc_dev, dev)
+
+extern struct class nfc_class;
+
+struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
+					u32 supported_protocols);
+
+/**
+ * nfc_free_device - free nfc device
+ *
+ * @dev: The nfc device to free
+ */
+static inline void nfc_free_device(struct nfc_dev *dev)
+{
+	put_device(&dev->dev);
+}
+
+int nfc_register_device(struct nfc_dev *dev);
+
+void nfc_unregister_device(struct nfc_dev *dev);
+
+/**
+ * nfc_set_parent_dev - set the parent device
+ *
+ * @nfc_dev: The nfc device whose parent is being set
+ * @dev: The parent device
+ */
+static inline void nfc_set_parent_dev(struct nfc_dev *nfc_dev,
+					struct device *dev)
+{
+	nfc_dev->dev.parent = dev;
+}
+
+/**
+ * nfc_set_drvdata - set driver specifc data
+ *
+ * @dev: The nfc device
+ * @data: Pointer to driver specifc data
+ */
+static inline void nfc_set_drvdata(struct nfc_dev *dev, void *data)
+{
+	dev_set_drvdata(&dev->dev, data);
+}
+
+/**
+ * nfc_get_drvdata - get driver specifc data
+ *
+ * @dev: The nfc device
+ */
+static inline void *nfc_get_drvdata(struct nfc_dev *dev)
+{
+	return dev_get_drvdata(&dev->dev);
+}
+
+/**
+ * nfc_device_name - get the nfc device name
+ *
+ * @dev: The nfc device whose name to return
+ */
+static inline const char *nfc_device_name(struct nfc_dev *dev)
+{
+	return dev_name(&dev->dev);
+}
+
+struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp);
+
+#endif /* __NET_NFC_H */
@@ -322,6 +322,7 @@
 source "net/9p/Kconfig"
 source "net/caif/Kconfig"
 source "net/ceph/Kconfig"
+source "net/nfc/Kconfig"
  
  
 endif   # if NET
@@ -68,4 +68,5 @@
 obj-$(CONFIG_DNS_RESOLVER)	+= dns_resolver/
 obj-$(CONFIG_CEPH_LIB)		+= ceph/
 obj-$(CONFIG_BATMAN_ADV)	+= batman-adv/
+obj-$(CONFIG_NFC)		+= nfc/
+#
+# NFC sybsystem configuration
+#
+
+menuconfig NFC
+	depends on NET && EXPERIMENTAL
+	tristate "NFC subsystem support (EXPERIMENTAL)"
+	default n
+	help
+	  Say Y here if you want to build support for NFC (Near field
+	  communication) devices.
+
+	  To compile this support as a module, choose M here: the module will
+	  be called nfc.
+
+source "drivers/nfc/Kconfig"
+#
+# Makefile for the Linux NFC subsystem.
+#
+
+obj-$(CONFIG_NFC) += nfc.o
+
+nfc-objs := core.o
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
+ *
+ * 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.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "nfc.h"
+
+#define VERSION "0.1"
+
+int nfc_devlist_generation;
+DEFINE_MUTEX(nfc_devlist_mutex);
+
+int nfc_printk(const char *level, const char *format, ...)
+{
+	struct va_format vaf;
+	va_list args;
+	int r;
+
+	va_start(args, format);
+
+	vaf.fmt = format;
+	vaf.va = &args;
+
+	r = printk("%sNFC: %pV\n", level, &vaf);
+
+	va_end(args);
+
+	return r;
+}
+EXPORT_SYMBOL(nfc_printk);
+
+/**
+ * nfc_start_poll - start polling for nfc targets
+ *
+ * @dev: The nfc device that must start polling
+ * @protocols: bitset of nfc protocols that must be used for polling
+ *
+ * The device remains polling for targets until a target is found or
+ * the nfc_stop_poll function is called.
+ */
+int nfc_start_poll(struct nfc_dev *dev, u32 protocols)
+{
+	int rc;
+
+	nfc_dbg("dev_name=%s protocols=0x%x", dev_name(&dev->dev), protocols);
+
+	if (!protocols)
+		return -EINVAL;
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (dev->polling) {
+		rc = -EBUSY;
+		goto error;
+	}
+
+	rc = dev->ops->start_poll(dev, protocols);
+	if (!rc)
+		dev->polling = true;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_stop_poll - stop polling for nfc targets
+ *
+ * @dev: The nfc device that must stop polling
+ */
+int nfc_stop_poll(struct nfc_dev *dev)
+{
+	int rc = 0;
+
+	nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	if (!dev->polling) {
+		rc = -EINVAL;
+		goto error;
+	}
+
+	dev->ops->stop_poll(dev);
+	dev->polling = false;
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_activate_target - prepare the target for data exchange
+ *
+ * @dev: The nfc device that found the target
+ * @target_idx: index of the target that must be activated
+ * @protocol: nfc protocol that will be used for data exchange
+ */
+int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
+{
+	int rc;
+
+	nfc_dbg("dev_name=%s target_idx=%u protocol=%u", dev_name(&dev->dev),
+							target_idx, protocol);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	rc = dev->ops->activate_target(dev, target_idx, protocol);
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_deactivate_target - deactivate a nfc target
+ *
+ * @dev: The nfc device that found the target
+ * @target_idx: index of the target that must be deactivated
+ */
+int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
+{
+	int rc = 0;
+
+	nfc_dbg("dev_name=%s target_idx=%u", dev_name(&dev->dev), target_idx);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		goto error;
+	}
+
+	dev->ops->deactivate_target(dev, target_idx);
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_data_exchange - transceive data
+ *
+ * @dev: The nfc device that found the target
+ * @target_idx: index of the target
+ * @skb: data to be sent
+ * @cb: callback called when the response is received
+ * @cb_context: parameter for the callback function
+ *
+ * The user must wait for the callback before calling this function again.
+ */
+int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx,
+					struct sk_buff *skb,
+					data_exchange_cb_t cb,
+					void *cb_context)
+{
+	int rc;
+
+	nfc_dbg("dev_name=%s target_idx=%u skb->len=%u", dev_name(&dev->dev),
+							target_idx, skb->len);
+
+	device_lock(&dev->dev);
+
+	if (!device_is_registered(&dev->dev)) {
+		rc = -ENODEV;
+		kfree_skb(skb);
+		goto error;
+	}
+
+	rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context);
+
+error:
+	device_unlock(&dev->dev);
+	return rc;
+}
+
+/**
+ * nfc_alloc_skb - allocate a skb for data exchange responses
+ *
+ * @size: size to allocate
+ * @gfp: gfp flags
+ */
+struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp)
+{
+	struct sk_buff *skb;
+	unsigned int total_size;
+
+	total_size = size + 1;
+	skb = alloc_skb(total_size, gfp);
+
+	if (skb)
+		skb_reserve(skb, 1);
+
+	return skb;
+}
+EXPORT_SYMBOL(nfc_alloc_skb);
+
+static void nfc_release(struct device *d)
+{
+	struct nfc_dev *dev = to_nfc_dev(d);
+
+	nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+	kfree(dev);
+}
+
+struct class nfc_class = {
+	.name = "nfc",
+	.dev_release = nfc_release,
+};
+EXPORT_SYMBOL(nfc_class);
+
+static int match_idx(struct device *d, void *data)
+{
+	struct nfc_dev *dev = to_nfc_dev(d);
+	unsigned *idx = data;
+
+	return dev->idx == *idx;
+}
+
+struct nfc_dev *nfc_get_device(unsigned idx)
+{
+	struct device *d;
+
+	d = class_find_device(&nfc_class, NULL, &idx, match_idx);
+	if (!d)
+		return NULL;
+
+	return to_nfc_dev(d);
+}
+
+/**
+ * nfc_allocate_device - allocate a new nfc device
+ *
+ * @ops: device operations
+ * @supported_protocols: NFC protocols supported by the device
+ */
+struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
+					u32 supported_protocols)
+{
+	static atomic_t dev_no = ATOMIC_INIT(0);
+	struct nfc_dev *dev;
+
+	if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
+		!ops->deactivate_target || !ops->data_exchange)
+		return NULL;
+
+	if (!supported_protocols)
+		return NULL;
+
+	dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	dev->dev.class = &nfc_class;
+	dev->idx = atomic_inc_return(&dev_no) - 1;
+	dev_set_name(&dev->dev, "nfc%d", dev->idx);
+	device_initialize(&dev->dev);
+
+	dev->ops = ops;
+	dev->supported_protocols = supported_protocols;
+
+	return dev;
+}
+EXPORT_SYMBOL(nfc_allocate_device);
+
+/**
+ * nfc_register_device - register a nfc device in the nfc subsystem
+ *
+ * @dev: The nfc device to register
+ */
+int nfc_register_device(struct nfc_dev *dev)
+{
+	int rc;
+
+	nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+	mutex_lock(&nfc_devlist_mutex);
+	nfc_devlist_generation++;
+	rc = device_add(&dev->dev);
+	mutex_unlock(&nfc_devlist_mutex);
+
+	return rc;
+}
+EXPORT_SYMBOL(nfc_register_device);
+
+/**
+ * nfc_unregister_device - unregister a nfc device in the nfc subsystem
+ *
+ * @dev: The nfc device to unregister
+ */
+void nfc_unregister_device(struct nfc_dev *dev)
+{
+	nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+	mutex_lock(&nfc_devlist_mutex);
+	nfc_devlist_generation++;
+
+	/* lock to avoid unregistering a device while an operation
+	   is in progress */
+	device_lock(&dev->dev);
+	device_del(&dev->dev);
+	device_unlock(&dev->dev);
+
+	mutex_unlock(&nfc_devlist_mutex);
+}
+EXPORT_SYMBOL(nfc_unregister_device);
+
+static int __init nfc_init(void)
+{
+	nfc_info("NFC Core ver %s", VERSION);
+
+	return class_register(&nfc_class);
+}
+
+static void __exit nfc_exit(void)
+{
+	class_unregister(&nfc_class);
+}
+
+subsys_initcall(nfc_init);
+module_exit(nfc_exit);
+
+MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
+MODULE_DESCRIPTION("NFC Core ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");
+/*
+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
+ *
+ * Authors:
+ *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
+ *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
+ *
+ * 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 __LOCAL_NFC_H
+#define __LOCAL_NFC_H
+
+#include <net/nfc.h>
+
+__attribute__((format (printf, 2, 3)))
+int nfc_printk(const char *level, const char *fmt, ...);
+
+#define nfc_info(fmt, arg...) nfc_printk(KERN_INFO, fmt, ##arg)
+#define nfc_err(fmt, arg...) nfc_printk(KERN_ERR, fmt, ##arg)
+#define nfc_dbg(fmt, arg...) pr_debug(fmt "\n", ##arg)
+
+extern int nfc_devlist_generation;
+extern struct mutex nfc_devlist_mutex;
+
+struct nfc_dev *nfc_get_device(unsigned idx);
+
+static inline void nfc_put_device(struct nfc_dev *dev)
+{
+	put_device(&dev->dev);
+}
+
+static inline void nfc_device_iter_init(struct class_dev_iter *iter)
+{
+	class_dev_iter_init(iter, &nfc_class, NULL, NULL);
+}
+
+static inline struct nfc_dev *nfc_device_iter_next(struct class_dev_iter *iter)
+{
+	struct device *d = class_dev_iter_next(iter);
+	if (!d)
+		return NULL;
+
+	return to_nfc_dev(d);
+}
+
+static inline void nfc_device_iter_exit(struct class_dev_iter *iter)
+{
+	class_dev_iter_exit(iter);
+}
+
+int nfc_start_poll(struct nfc_dev *dev, u32 protocols);
+
+int nfc_stop_poll(struct nfc_dev *dev);
+
+int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol);
+
+int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx);
+
+int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx,
+					struct sk_buff *skb,
+					data_exchange_cb_t cb,
+					void *cb_context);
+
+#endif /* __LOCAL_NFC_H */
...	...	@@ -92,8 +92,6 @@
92	92
93	93	source "drivers/leds/Kconfig"
94	94
95		-source "drivers/nfc/Kconfig"
96		-
97	95	source "drivers/accessibility/Kconfig"
98	96
99	97	source "drivers/infiniband/Kconfig"
...	...	@@ -120,4 +120,5 @@
120	120	obj-y += clk/
121	121
122	122	obj-$(CONFIG_HWSPINLOCK) += hwspinlock/
	123	+obj-$(CONFIG_NFC) += nfc/
...	...	@@ -2,18 +2,9 @@
2	2	# Near Field Communication (NFC) devices
3	3	#
4	4
5		-menuconfig NFC_DEVICES
6		- bool "Near Field Communication (NFC) devices"
7		- default n
8		- ---help---
9		- You'll have to say Y if your computer contains an NFC device that
10		- you want to use under Linux.
	5	+menu "Near Field Communication (NFC) devices"
	6	+ depends on NFC
11	7
12		- You can say N here if you don't have any Near Field Communication
13		- devices connected to your computer.
14		-
15		-if NFC_DEVICES
16		-
17	8	config PN544_NFC
18	9	tristate "PN544 NFC driver"
19	10	depends on I2C
...	...	@@ -26,6 +17,5 @@
26	17	To compile this driver as a module, choose m here. The module will
27	18	be called pn544.
28	19
29		-
30		-endif # NFC_DEVICES
	20	+endmenu
...	...	@@ -3,4 +3,6 @@
3	3	#
4	4
5	5	obj-$(CONFIG_PN544_NFC) += pn544.o
	6	+
	7	+ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG
	1	+/*
	2	+ * Copyright (C) 2011 Instituto Nokia de Tecnologia
	3	+ *
	4	+ * Authors:
	5	+ * Lauro Ramos Venancio <lauro.venancio@openbossa.org>
	6	+ * Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
	7	+ *
	8	+ * This program is free software; you can redistribute it and/or modify
	9	+ * it under the terms of the GNU General Public License as published by
	10	+ * the Free Software Foundation; either version 2 of the License, or
	11	+ * (at your option) any later version.
	12	+ *
	13	+ * This program is distributed in the hope that it will be useful,
	14	+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	+ * GNU General Public License for more details.
	17	+ *
	18	+ * You should have received a copy of the GNU General Public License
	19	+ * along with this program; if not, write to the
	20	+ * Free Software Foundation, Inc.,
	21	+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	22	+ */
	23	+
	24	+#ifndef __NET_NFC_H
	25	+#define __NET_NFC_H
	26	+
	27	+#include <linux/device.h>
	28	+#include <linux/skbuff.h>
	29	+
	30	+#define nfc_dev_info(dev, fmt, arg...) dev_info((dev), "NFC: " fmt "\n", ## arg)
	31	+#define nfc_dev_err(dev, fmt, arg...) dev_err((dev), "NFC: " fmt "\n", ## arg)
	32	+#define nfc_dev_dbg(dev, fmt, arg...) dev_dbg((dev), fmt "\n", ## arg)
	33	+
	34	+struct nfc_dev;
	35	+
	36	+/**
	37	+ * data_exchange_cb_t - Definition of nfc_data_exchange callback
	38	+ *
	39	+ * @context: nfc_data_exchange cb_context parameter
	40	+ * @skb: response data
	41	+ * @err: If an error has occurred during data exchange, it is the
	42	+ * error number. Zero means no error.
	43	+ *
	44	+ * When a rx or tx package is lost or corrupted or the target gets out
	45	+ * of the operating field, err is -EIO.
	46	+ */
	47	+typedef void (data_exchange_cb_t)(void context, struct sk_buff *skb,
	48	+ int err);
	49	+
	50	+struct nfc_ops {
	51	+ int (start_poll)(struct nfc_dev dev, u32 protocols);
	52	+ void (stop_poll)(struct nfc_dev dev);
	53	+ int (activate_target)(struct nfc_dev dev, u32 target_idx,
	54	+ u32 protocol);
	55	+ void (deactivate_target)(struct nfc_dev dev, u32 target_idx);
	56	+ int (data_exchange)(struct nfc_dev dev, u32 target_idx,
	57	+ struct sk_buff *skb, data_exchange_cb_t cb,
	58	+ void *cb_context);
	59	+};
	60	+
	61	+struct nfc_dev {
	62	+ unsigned idx;
	63	+ struct device dev;
	64	+ bool polling;
	65	+ u32 supported_protocols;
	66	+
	67	+ struct nfc_ops *ops;
	68	+};
	69	+#define to_nfc_dev(_dev) container_of(_dev, struct nfc_dev, dev)
	70	+
	71	+extern struct class nfc_class;
	72	+
	73	+struct nfc_dev nfc_allocate_device(struct nfc_ops ops,
	74	+ u32 supported_protocols);
	75	+
	76	+/**
	77	+ * nfc_free_device - free nfc device
	78	+ *
	79	+ * @dev: The nfc device to free
	80	+ */
	81	+static inline void nfc_free_device(struct nfc_dev *dev)
	82	+{
	83	+ put_device(&dev->dev);
	84	+}
	85	+
	86	+int nfc_register_device(struct nfc_dev *dev);
	87	+
	88	+void nfc_unregister_device(struct nfc_dev *dev);
	89	+
	90	+/**
	91	+ * nfc_set_parent_dev - set the parent device
	92	+ *
	93	+ * @nfc_dev: The nfc device whose parent is being set
	94	+ * @dev: The parent device
	95	+ */
	96	+static inline void nfc_set_parent_dev(struct nfc_dev *nfc_dev,
	97	+ struct device *dev)
	98	+{
	99	+ nfc_dev->dev.parent = dev;
	100	+}
	101	+
	102	+/**
	103	+ * nfc_set_drvdata - set driver specifc data
	104	+ *
	105	+ * @dev: The nfc device
	106	+ * @data: Pointer to driver specifc data
	107	+ */
	108	+static inline void nfc_set_drvdata(struct nfc_dev dev, void data)
	109	+{
	110	+ dev_set_drvdata(&dev->dev, data);
	111	+}
	112	+
	113	+/**
	114	+ * nfc_get_drvdata - get driver specifc data
	115	+ *
	116	+ * @dev: The nfc device
	117	+ */
	118	+static inline void nfc_get_drvdata(struct nfc_dev dev)
	119	+{
	120	+ return dev_get_drvdata(&dev->dev);
	121	+}
	122	+
	123	+/**
	124	+ * nfc_device_name - get the nfc device name
	125	+ *
	126	+ * @dev: The nfc device whose name to return
	127	+ */
	128	+static inline const char nfc_device_name(struct nfc_dev dev)
	129	+{
	130	+ return dev_name(&dev->dev);
	131	+}
	132	+
	133	+struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp);
	134	+
	135	+#endif /* __NET_NFC_H */
...	...	@@ -322,6 +322,7 @@
322	322	source "net/9p/Kconfig"
323	323	source "net/caif/Kconfig"
324	324	source "net/ceph/Kconfig"
	325	+source "net/nfc/Kconfig"
325	326
326	327
327	328	endif # if NET
...	...	@@ -68,4 +68,5 @@
68	68	obj-$(CONFIG_DNS_RESOLVER) += dns_resolver/
69	69	obj-$(CONFIG_CEPH_LIB) += ceph/
70	70	obj-$(CONFIG_BATMAN_ADV) += batman-adv/
	71	+obj-$(CONFIG_NFC) += nfc/
	1	+#
	2	+# NFC sybsystem configuration
	3	+#
	4	+
	5	+menuconfig NFC
	6	+ depends on NET && EXPERIMENTAL
	7	+ tristate "NFC subsystem support (EXPERIMENTAL)"
	8	+ default n
	9	+ help
	10	+ Say Y here if you want to build support for NFC (Near field
	11	+ communication) devices.
	12	+
	13	+ To compile this support as a module, choose M here: the module will
	14	+ be called nfc.
	15	+
	16	+source "drivers/nfc/Kconfig"
	1	+#
	2	+# Makefile for the Linux NFC subsystem.
	3	+#
	4	+
	5	+obj-$(CONFIG_NFC) += nfc.o
	6	+
	7	+nfc-objs := core.o