NFC: nfcsim: Make use of the Digital layer

#include <linux/module.h>

#include <linux/nfc.h>

#include <net/nfc/nfc.h>

#include <net/nfc/digital.h>

#define DEV_ERR(_dev, fmt, args...) nfc_err(&_dev->nfc_dev->dev, \

#define NFCSIM_ERR(d, fmt, args...) nfc_err(&d->nfc_digital_dev->nfc_dev->dev, \

					    "%s: " fmt, __func__, ## args)

#define DEV_DBG(_dev, fmt, args...) dev_dbg(&_dev->nfc_dev->dev, \

#define NFCSIM_DBG(d, fmt, args...) dev_dbg(&d->nfc_digital_dev->nfc_dev->dev, \

					    "%s: " fmt, __func__, ## args)

#define NFCSIM_VERSION "0.1"

#define NFCSIM_VERSION "0.2"

#define NFCSIM_POLL_NONE	0

#define NFCSIM_POLL_INITIATOR	1

#define NFCSIM_POLL_TARGET	2

#define NFCSIM_POLL_DUAL	(NFCSIM_POLL_INITIATOR | NFCSIM_POLL_TARGET)

#define NFCSIM_MODE_NONE	0

#define NFCSIM_MODE_INITIATOR	1

#define NFCSIM_MODE_TARGET	2

#define RX_DEFAULT_DELAY	5

#define NFCSIM_CAPABILITIES (NFC_DIGITAL_DRV_CAPS_IN_CRC   | \

			     NFC_DIGITAL_DRV_CAPS_TG_CRC)

struct nfcsim {

	struct nfc_dev *nfc_dev;

	struct nfc_digital_dev *nfc_digital_dev;

	struct mutex lock;

	struct delayed_work recv_work;

	struct work_struct recv_work;

	struct delayed_work send_work;

	struct sk_buff *clone_skb;

	struct nfcsim_link *link_in;

	struct nfcsim_link *link_out;

	struct delayed_work poll_work;

	u8 polling_mode;

	u8 curr_polling_mode;

	bool up;

	u8 mode;

	u8 rf_tech;

	u8 shutting_down;

	u16 recv_timeout;

	u8 up;

	nfc_digital_cmd_complete_t cb;

	void *arg;

};

	u8 initiator;

struct nfcsim_link {

	struct mutex lock;

	u32 rx_delay;

	u8 rf_tech;

	u8 mode;

	data_exchange_cb_t cb;

	void *cb_context;

	u8 shutdown;

	struct nfcsim *peer_dev;

	struct sk_buff *skb;

	wait_queue_head_t recv_wait;

	u8 cond;

};

static struct nfcsim *dev0;

static struct nfcsim *dev1;

static struct workqueue_struct *wq;

static void nfcsim_cleanup_dev(struct nfcsim *dev, u8 shutdown)

static struct nfcsim_link *nfcsim_link_new(void)

{

	DEV_DBG(dev, "shutdown=%d\n", shutdown);

	struct nfcsim_link *link;

	mutex_lock(&dev->lock);

	link = kzalloc(sizeof(struct nfcsim_link), GFP_KERNEL);

	if (!link)

		return NULL;

	dev->polling_mode = NFCSIM_POLL_NONE;

	dev->shutting_down = shutdown;

	dev->cb = NULL;

	dev_kfree_skb(dev->clone_skb);

	dev->clone_skb = NULL;

	mutex_init(&link->lock);

	init_waitqueue_head(&link->recv_wait);

	mutex_unlock(&dev->lock);

	cancel_delayed_work_sync(&dev->poll_work);

	cancel_delayed_work_sync(&dev->recv_work);

	return link;

}

static int nfcsim_target_found(struct nfcsim *dev)

static void nfcsim_link_free(struct nfcsim_link *link)

{

	struct nfc_target nfc_tgt;

	DEV_DBG(dev, "\n");

	memset(&nfc_tgt, 0, sizeof(struct nfc_target));

	nfc_tgt.supported_protocols = NFC_PROTO_NFC_DEP_MASK;

	nfc_targets_found(dev->nfc_dev, &nfc_tgt, 1);

	return 0;

	dev_kfree_skb(link->skb);

	kfree(link);

}

static int nfcsim_dev_up(struct nfc_dev *nfc_dev)

static void nfcsim_link_recv_wake(struct nfcsim_link *link)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	DEV_DBG(dev, "\n");

	mutex_lock(&dev->lock);

	dev->up = 1;

	mutex_unlock(&dev->lock);

	return 0;

	link->cond = 1;

	wake_up_interruptible(&link->recv_wait);

}

static int nfcsim_dev_down(struct nfc_dev *nfc_dev)

static void nfcsim_link_set_skb(struct nfcsim_link *link, struct sk_buff *skb,

				u8 rf_tech, u8 mode)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	DEV_DBG(dev, "\n");

	mutex_lock(&dev->lock);

	mutex_lock(&link->lock);

	dev->up = 0;

	dev_kfree_skb(link->skb);

	link->skb = skb;

	link->rf_tech = rf_tech;

	link->mode = mode;

	mutex_unlock(&dev->lock);

	return 0;

	mutex_unlock(&link->lock);

}

static int nfcsim_dep_link_up(struct nfc_dev *nfc_dev,

			      struct nfc_target *target,

			      u8 comm_mode, u8 *gb, size_t gb_len)

static void nfcsim_link_recv_cancel(struct nfcsim_link *link)

{

	int rc;

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	struct nfcsim *peer = dev->peer_dev;

	u8 *remote_gb;

	size_t remote_gb_len;

	DEV_DBG(dev, "target_idx: %d, comm_mode: %d\n", target->idx, comm_mode);

	mutex_lock(&link->lock);

	mutex_lock(&peer->lock);

	link->mode = NFCSIM_MODE_NONE;

	nfc_tm_activated(peer->nfc_dev, NFC_PROTO_NFC_DEP_MASK,

			 NFC_COMM_ACTIVE, gb, gb_len);

	mutex_unlock(&link->lock);

	remote_gb = nfc_get_local_general_bytes(peer->nfc_dev, &remote_gb_len);

	if (!remote_gb) {

		DEV_ERR(peer, "Can't get remote general bytes\n");

		mutex_unlock(&peer->lock);

		return -EINVAL;

	nfcsim_link_recv_wake(link);

}

	mutex_unlock(&peer->lock);

	mutex_lock(&dev->lock);

	rc = nfc_set_remote_general_bytes(nfc_dev, remote_gb, remote_gb_len);

	if (rc) {

		DEV_ERR(dev, "Can't set remote general bytes\n");

		mutex_unlock(&dev->lock);

		return rc;

	}

	rc = nfc_dep_link_is_up(nfc_dev, target->idx, NFC_COMM_ACTIVE,

				NFC_RF_INITIATOR);

	mutex_unlock(&dev->lock);

	return rc;

}

static int nfcsim_dep_link_down(struct nfc_dev *nfc_dev)

static void nfcsim_link_shutdown(struct nfcsim_link *link)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	mutex_lock(&link->lock);

	DEV_DBG(dev, "\n");

	link->shutdown = 1;

	link->mode = NFCSIM_MODE_NONE;

	nfcsim_cleanup_dev(dev, 0);

	mutex_unlock(&link->lock);

	return 0;

	nfcsim_link_recv_wake(link);

}

static int nfcsim_start_poll(struct nfc_dev *nfc_dev,

			     u32 im_protocols, u32 tm_protocols)

static struct sk_buff *nfcsim_link_recv_skb(struct nfcsim_link *link,

					    int timeout, u8 rf_tech, u8 mode)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	int rc;

	struct sk_buff *skb;

	mutex_lock(&dev->lock);

	rc = wait_event_interruptible_timeout(link->recv_wait,

					      link->cond,

					      msecs_to_jiffies(timeout));

	if (dev->polling_mode != NFCSIM_POLL_NONE) {

		DEV_ERR(dev, "Already in polling mode\n");

		rc = -EBUSY;

		goto exit;

	}

	mutex_lock(&link->lock);

	if (im_protocols & NFC_PROTO_NFC_DEP_MASK)

		dev->polling_mode |= NFCSIM_POLL_INITIATOR;

	skb = link->skb;

	link->skb = NULL;

	if (tm_protocols & NFC_PROTO_NFC_DEP_MASK)

		dev->polling_mode |= NFCSIM_POLL_TARGET;

	if (!rc) {

		rc = -ETIMEDOUT;

		goto done;

	}

	if (dev->polling_mode == NFCSIM_POLL_NONE) {

		DEV_ERR(dev, "Unsupported polling mode\n");

	if (!skb || link->rf_tech != rf_tech || link->mode == mode) {

		rc = -EINVAL;

		goto exit;

		goto done;

	}

	dev->initiator = 0;

	dev->curr_polling_mode = NFCSIM_POLL_NONE;

	queue_delayed_work(wq, &dev->poll_work, 0);

	DEV_DBG(dev, "Start polling: im: 0x%X, tm: 0x%X\n", im_protocols,

		tm_protocols);

	rc = 0;

exit:

	mutex_unlock(&dev->lock);

	return rc;

	if (link->shutdown) {

		rc = -ENODEV;

		goto done;

	}

static void nfcsim_stop_poll(struct nfc_dev *nfc_dev)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	DEV_DBG(dev, "Stop poll\n");

	mutex_lock(&dev->lock);

done:

	mutex_unlock(&link->lock);

	dev->polling_mode = NFCSIM_POLL_NONE;

	mutex_unlock(&dev->lock);

	cancel_delayed_work_sync(&dev->poll_work);

	if (rc < 0) {

		dev_kfree_skb(skb);

		skb = ERR_PTR(rc);

	}

static int nfcsim_activate_target(struct nfc_dev *nfc_dev,

				  struct nfc_target *target, u32 protocol)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	link->cond = 0;

	DEV_DBG(dev, "\n");

	return -ENOTSUPP;

	return skb;

}

static void nfcsim_deactivate_target(struct nfc_dev *nfc_dev,

				     struct nfc_target *target, u8 mode)

static void nfcsim_send_wq(struct work_struct *work)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	struct nfcsim *dev = container_of(work, struct nfcsim, send_work.work);

	DEV_DBG(dev, "\n");

	/*

	 * To effectively send data, the device just wake up its link_out which

	 * is the link_in of the peer device. The exchanged skb has already been

	 * stored in the dev->link_out through nfcsim_link_set_skb().

	 */

	nfcsim_link_recv_wake(dev->link_out);

}

static void nfcsim_wq_recv(struct work_struct *work)

static void nfcsim_recv_wq(struct work_struct *work)

{

	struct nfcsim *dev = container_of(work, struct nfcsim,

					  recv_work.work);

	struct nfcsim *dev = container_of(work, struct nfcsim, recv_work);

	struct sk_buff *skb;

	mutex_lock(&dev->lock);

	skb = nfcsim_link_recv_skb(dev->link_in, dev->recv_timeout,

				   dev->rf_tech, dev->mode);

	if (dev->shutting_down || !dev->up || !dev->clone_skb) {

		dev_kfree_skb(dev->clone_skb);

		goto exit;

	}

	if (!dev->up) {

		NFCSIM_ERR(dev, "Device is down\n");

	if (dev->initiator) {

		if (!dev->cb) {

			DEV_ERR(dev, "Null recv callback\n");

			dev_kfree_skb(dev->clone_skb);

			goto exit;

		}

		if (!IS_ERR(skb))

			dev_kfree_skb(skb);

		dev->cb(dev->cb_context, dev->clone_skb, 0);

		dev->cb = NULL;

	} else {

		nfc_tm_data_received(dev->nfc_dev, dev->clone_skb);

		skb = ERR_PTR(-ENODEV);

	}

exit:

	dev->clone_skb = NULL;

	mutex_unlock(&dev->lock);

	dev->cb(dev->nfc_digital_dev, dev->arg, skb);

}

static int nfcsim_tx(struct nfc_dev *nfc_dev, struct nfc_target *target,

		     struct sk_buff *skb, data_exchange_cb_t cb,

		     void *cb_context)

static int nfcsim_send(struct nfc_digital_dev *ddev, struct sk_buff *skb,

		       u16 timeout, nfc_digital_cmd_complete_t cb, void *arg)

{

	struct nfcsim *dev = nfc_get_drvdata(nfc_dev);

	struct nfcsim *peer = dev->peer_dev;

	int err;

	struct nfcsim *dev = nfc_digital_get_drvdata(ddev);

	u8 delay;

	mutex_lock(&dev->lock);

	if (dev->shutting_down || !dev->up) {

		mutex_unlock(&dev->lock);

		err = -ENODEV;

		goto exit;

	if (!dev->up) {

		NFCSIM_ERR(dev, "Device is down\n");

		return -ENODEV;

	}

	dev->recv_timeout = timeout;

	dev->cb = cb;

	dev->cb_context = cb_context;

	dev->arg = arg;

	mutex_unlock(&dev->lock);

	schedule_work(&dev->recv_work);

	mutex_lock(&peer->lock);

	if (skb) {

		nfcsim_link_set_skb(dev->link_out, skb, dev->rf_tech,

				    dev->mode);

	peer->clone_skb = skb_clone(skb, GFP_KERNEL);

		/* Add random delay (between 3 and 10 ms) before sending data */

		get_random_bytes(&delay, 1);

		delay = 3 + (delay & 0x07);

	if (!peer->clone_skb) {

		DEV_ERR(dev, "skb_clone failed\n");

		mutex_unlock(&peer->lock);

		err = -ENOMEM;

		goto exit;

		schedule_delayed_work(&dev->send_work, msecs_to_jiffies(delay));

	}

	/* This simulates an arbitrary transmission delay between the 2 devices.

	 * If packet transmission occurs immediately between them, we have a

	 * non-stop flow of several tens of thousands SYMM packets per second

	 * and a burning cpu.

	 */

	queue_delayed_work(wq, &peer->recv_work,

			msecs_to_jiffies(dev->rx_delay));

	mutex_unlock(&peer->lock);

	return 0;

}

	err = 0;

exit:

	dev_kfree_skb(skb);

static void nfcsim_abort_cmd(struct nfc_digital_dev *ddev)

{

	struct nfcsim *dev = nfc_digital_get_drvdata(ddev);

	return err;

	nfcsim_link_recv_cancel(dev->link_in);

}

static int nfcsim_im_transceive(struct nfc_dev *nfc_dev,

				struct nfc_target *target, struct sk_buff *skb,

				data_exchange_cb_t cb, void *cb_context)

static int nfcsim_switch_rf(struct nfc_digital_dev *ddev, bool on)

{

	return nfcsim_tx(nfc_dev, target, skb, cb, cb_context);

	struct nfcsim *dev = nfc_digital_get_drvdata(ddev);

	dev->up = on;

	return 0;

}

static int nfcsim_tm_send(struct nfc_dev *nfc_dev, struct sk_buff *skb)

static int nfcsim_in_configure_hw(struct nfc_digital_dev *ddev,

					  int type, int param)

{

	return nfcsim_tx(nfc_dev, NULL, skb, NULL, NULL);

}

static struct nfc_ops nfcsim_nfc_ops = {

	.dev_up = nfcsim_dev_up,

	.dev_down = nfcsim_dev_down,

	.dep_link_up = nfcsim_dep_link_up,

	.dep_link_down = nfcsim_dep_link_down,

	.start_poll = nfcsim_start_poll,

	.stop_poll = nfcsim_stop_poll,

	.activate_target = nfcsim_activate_target,

	.deactivate_target = nfcsim_deactivate_target,

	.im_transceive = nfcsim_im_transceive,

	.tm_send = nfcsim_tm_send,

};

	struct nfcsim *dev = nfc_digital_get_drvdata(ddev);

static void nfcsim_set_polling_mode(struct nfcsim *dev)

{

	if (dev->polling_mode == NFCSIM_POLL_NONE) {

		dev->curr_polling_mode = NFCSIM_POLL_NONE;

		return;

	}

	switch (type) {

	case NFC_DIGITAL_CONFIG_RF_TECH:

		dev->up = true;

		dev->mode = NFCSIM_MODE_INITIATOR;

		dev->rf_tech = param;

		break;

	if (dev->curr_polling_mode == NFCSIM_POLL_NONE) {

		if (dev->polling_mode & NFCSIM_POLL_INITIATOR)

			dev->curr_polling_mode = NFCSIM_POLL_INITIATOR;

		else

			dev->curr_polling_mode = NFCSIM_POLL_TARGET;

	case NFC_DIGITAL_CONFIG_FRAMING:

		break;

		return;

	default:

		NFCSIM_ERR(dev, "Invalid configuration type: %d\n", type);

		return -EINVAL;

	}

	if (dev->polling_mode == NFCSIM_POLL_DUAL) {

		if (dev->curr_polling_mode == NFCSIM_POLL_TARGET)

			dev->curr_polling_mode = NFCSIM_POLL_INITIATOR;

		else

			dev->curr_polling_mode = NFCSIM_POLL_TARGET;

	return 0;

}

static int nfcsim_in_send_cmd(struct nfc_digital_dev *ddev,

			       struct sk_buff *skb, u16 timeout,

			       nfc_digital_cmd_complete_t cb, void *arg)

{

	return nfcsim_send(ddev, skb, timeout, cb, arg);

}

static void nfcsim_wq_poll(struct work_struct *work)

static int nfcsim_tg_configure_hw(struct nfc_digital_dev *ddev,

					  int type, int param)

{

	struct nfcsim *dev = container_of(work, struct nfcsim, poll_work.work);

	struct nfcsim *peer = dev->peer_dev;

	struct nfcsim *dev = nfc_digital_get_drvdata(ddev);

	/* These work items run on an ordered workqueue and are therefore

	 * serialized. So we can take both mutexes without being dead locked.

	 */

	mutex_lock(&dev->lock);

	mutex_lock(&peer->lock);

	switch (type) {

	case NFC_DIGITAL_CONFIG_RF_TECH:

		dev->up = true;

		dev->mode = NFCSIM_MODE_TARGET;

		dev->rf_tech = param;

		break;

	nfcsim_set_polling_mode(dev);

	case NFC_DIGITAL_CONFIG_FRAMING:

		break;

	if (dev->curr_polling_mode == NFCSIM_POLL_NONE) {

		DEV_DBG(dev, "Not polling\n");

		goto unlock;

	default:

		NFCSIM_ERR(dev, "Invalid configuration type: %d\n", type);

		return -EINVAL;

	}

	DEV_DBG(dev, "Polling as %s",

		dev->curr_polling_mode == NFCSIM_POLL_INITIATOR ?

		"initiator\n" : "target\n");

	if (dev->curr_polling_mode == NFCSIM_POLL_TARGET)

		goto sched_work;

	if (peer->curr_polling_mode == NFCSIM_POLL_TARGET) {

		peer->polling_mode = NFCSIM_POLL_NONE;

		dev->polling_mode = NFCSIM_POLL_NONE;

		dev->initiator = 1;

	return 0;

}

		nfcsim_target_found(dev);

static int nfcsim_tg_send_cmd(struct nfc_digital_dev *ddev,

			       struct sk_buff *skb, u16 timeout,

			       nfc_digital_cmd_complete_t cb, void *arg)

{

	return nfcsim_send(ddev, skb, timeout, cb, arg);

}

		goto unlock;

static int nfcsim_tg_listen(struct nfc_digital_dev *ddev, u16 timeout,

			    nfc_digital_cmd_complete_t cb, void *arg)

{

	return nfcsim_send(ddev, NULL, timeout, cb, arg);

}

sched_work:

	/* This defines the delay for an initiator to check if the other device

	 * is polling in target mode.

	 * If the device starts in dual mode polling, it switches between

	 * initiator and target at every round.

	 * Because the wq is ordered and only 1 work item is executed at a time,

	 * we'll always have one device polling as initiator and the other as

	 * target at some point, even if both are started in dual mode.

	 */

	queue_delayed_work(wq, &dev->poll_work, msecs_to_jiffies(200));

static struct nfc_digital_ops nfcsim_digital_ops = {

	.in_configure_hw = nfcsim_in_configure_hw,

	.in_send_cmd = nfcsim_in_send_cmd,

unlock:

	mutex_unlock(&peer->lock);

	mutex_unlock(&dev->lock);

}

	.tg_listen = nfcsim_tg_listen,

	.tg_configure_hw = nfcsim_tg_configure_hw,

	.tg_send_cmd = nfcsim_tg_send_cmd,

static struct nfcsim *nfcsim_init_dev(void)

	.abort_cmd = nfcsim_abort_cmd,

	.switch_rf = nfcsim_switch_rf,

};

static struct nfcsim *nfcsim_device_new(struct nfcsim_link *link_in,

					struct nfcsim_link *link_out)

{

	struct nfcsim *dev;

	int rc = -ENOMEM;

	int rc;

	dev = kzalloc(sizeof(*dev), GFP_KERNEL);

	if (dev == NULL)

	dev = kzalloc(sizeof(struct nfcsim), GFP_KERNEL);

	if (!dev)

		return ERR_PTR(-ENOMEM);

	mutex_init(&dev->lock);

	INIT_DELAYED_WORK(&dev->send_work, nfcsim_send_wq);

	INIT_WORK(&dev->recv_work, nfcsim_recv_wq);

	INIT_DELAYED_WORK(&dev->recv_work, nfcsim_wq_recv);

	INIT_DELAYED_WORK(&dev->poll_work, nfcsim_wq_poll);

	dev->nfc_dev = nfc_allocate_device(&nfcsim_nfc_ops,

	dev->nfc_digital_dev =

			nfc_digital_allocate_device(&nfcsim_digital_ops,

						    NFC_PROTO_NFC_DEP_MASK,

						    NFCSIM_CAPABILITIES,

						    0, 0);