Commit 963a82e0 authored by Olivier Guiter's avatar Olivier Guiter Committed by Samuel Ortiz
Browse files

NFC: pn533: Split large Tx frames in chunks 



On sending large frames (size > 262), we split it in multiple chunks and
send them asynchronously with MI bit.

Signed-off-by: default avatarOlivier Guiter <olivier.guiter@linux.intel.com>
Signed-off-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
parent 1575b9d8

drivers/nfc/pn533.c

+130 −14
Original line number Diff line number Diff line
@@ -363,12 +363,14 @@ struct pn533 { 
	struct urb *in_urb;



	struct sk_buff_head resp_q;

	struct sk_buff_head fragment_skb;



	struct workqueue_struct	*wq;

	struct work_struct cmd_work;

	struct work_struct cmd_complete_work;

	struct work_struct poll_work;

	struct work_struct mi_work;

	struct work_struct mi_rx_work;

	struct work_struct mi_tx_work;

	struct work_struct tg_work;

	struct work_struct rf_work;
@@ -378,6 +380,7 @@ struct pn533 { 
	struct mutex cmd_lock;  /* protects cmd queue */



	void *cmd_complete_mi_arg;

	void *cmd_complete_dep_arg;



	struct pn533_poll_modulations *poll_mod_active[PN533_POLL_MOD_MAX + 1];

	u8 poll_mod_count;
@@ -2328,7 +2331,15 @@ static int pn533_data_exchange_complete(struct pn533 *dev, void *_arg, 


	if (mi) {

		dev->cmd_complete_mi_arg = arg;

		queue_work(dev->wq, &dev->mi_work);

		queue_work(dev->wq, &dev->mi_rx_work);

		return -EINPROGRESS;

	}



	/* Prepare for the next round */

	if (skb_queue_len(&dev->fragment_skb) > 0) {

		dev->cmd_complete_dep_arg = arg;

		queue_work(dev->wq, &dev->mi_tx_work);



		return -EINPROGRESS;

	}
@@ -2349,6 +2360,50 @@ static int pn533_data_exchange_complete(struct pn533 *dev, void *_arg, 
	return rc;

}



/* Split the Tx skb into small chunks */

static int pn533_fill_fragment_skbs(struct pn533 *dev, struct sk_buff *skb)

{

	struct sk_buff *frag;

	int  frag_size;



	do {

		/* Remaining size */

		if (skb->len > PN533_CMD_DATAFRAME_MAXLEN)

			frag_size = PN533_CMD_DATAFRAME_MAXLEN;

		else

			frag_size = skb->len;



		/* Allocate and reserve */

		frag = pn533_alloc_skb(dev, frag_size);

		if (!frag) {

			skb_queue_purge(&dev->fragment_skb);

			break;

		}



		/* Reserve the TG/MI byte */

		skb_reserve(frag, 1);



		/* MI + TG */

		if (frag_size  == PN533_CMD_DATAFRAME_MAXLEN)

			*skb_push(frag, sizeof(u8)) = (PN533_CMD_MI_MASK | 1);

		else

			*skb_push(frag, sizeof(u8)) =  1; /* TG */



		memcpy(skb_put(frag, frag_size), skb->data, frag_size);



		/* Reduce the size of incoming buffer */

		skb_pull(skb, frag_size);



		/* Add this to skb_queue */

		skb_queue_tail(&dev->fragment_skb, frag);



	} while (skb->len > 0);



	dev_kfree_skb(skb);



	return skb_queue_len(&dev->fragment_skb);

}



static int pn533_transceive(struct nfc_dev *nfc_dev,

			    struct nfc_target *target, struct sk_buff *skb,

			    data_exchange_cb_t cb, void *cb_context)
@@ -2359,15 +2414,6 @@ static int pn533_transceive(struct nfc_dev *nfc_dev, 


	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);



	if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) {

		/* TODO: Implement support to multi-part data exchange */

		nfc_dev_err(&dev->interface->dev,

			    "Data length greater than the max allowed: %d",

			    PN533_CMD_DATAEXCH_DATA_MAXLEN);

		rc = -ENOSYS;

		goto error;

	}



	if (!dev->tgt_active_prot) {

		nfc_dev_err(&dev->interface->dev,

			    "Can't exchange data if there is no active target");
@@ -2395,7 +2441,20 @@ static int pn533_transceive(struct nfc_dev *nfc_dev, 
			break;

		}

	default:

		/* jumbo frame ? */

		if (skb->len > PN533_CMD_DATAEXCH_DATA_MAXLEN) {

			rc = pn533_fill_fragment_skbs(dev, skb);

			if (rc <= 0)

				goto error;



			skb = skb_dequeue(&dev->fragment_skb);

			if (!skb) {

				rc = -EIO;

				goto error;

			}

		} else {

			*skb_push(skb, sizeof(u8)) =  1; /* TG */

		}



		rc = pn533_send_data_async(dev, PN533_CMD_IN_DATA_EXCHANGE,

					   skb, pn533_data_exchange_complete,
@@ -2466,7 +2525,7 @@ static int pn533_tm_send(struct nfc_dev *nfc_dev, struct sk_buff *skb) 


static void pn533_wq_mi_recv(struct work_struct *work)

{

	struct pn533 *dev = container_of(work, struct pn533, mi_work);

	struct pn533 *dev = container_of(work, struct pn533, mi_rx_work);



	struct sk_buff *skb;

	int rc;
@@ -2514,6 +2573,61 @@ static void pn533_wq_mi_recv(struct work_struct *work) 
	queue_work(dev->wq, &dev->cmd_work);

}



static void pn533_wq_mi_send(struct work_struct *work)

{

	struct pn533 *dev = container_of(work, struct pn533, mi_tx_work);

	struct sk_buff *skb;

	int rc;



	nfc_dev_dbg(&dev->interface->dev, "%s", __func__);



	/* Grab the first skb in the queue */

	skb = skb_dequeue(&dev->fragment_skb);



	if (skb == NULL) {	/* No more data */

		/* Reset the queue for future use */

		skb_queue_head_init(&dev->fragment_skb);

		goto error;

	}



	switch (dev->device_type) {

	case PN533_DEVICE_PASORI:

		if (dev->tgt_active_prot != NFC_PROTO_FELICA) {

			rc = -EIO;

			break;

		}



		rc = pn533_send_cmd_direct_async(dev, PN533_CMD_IN_COMM_THRU,

						 skb,

						 pn533_data_exchange_complete,

						 dev->cmd_complete_dep_arg);



		break;



	default:

		/* Still some fragments? */

		rc = pn533_send_cmd_direct_async(dev,PN533_CMD_IN_DATA_EXCHANGE,

						 skb,

						 pn533_data_exchange_complete,

						 dev->cmd_complete_dep_arg);



		break;

	}



	if (rc == 0) /* success */

		return;



	nfc_dev_err(&dev->interface->dev,

		    "Error %d when trying to perform data_exchange", rc);



	dev_kfree_skb(skb);

	kfree(dev->cmd_complete_dep_arg);



error:

	pn533_send_ack(dev, GFP_KERNEL);

	queue_work(dev->wq, &dev->cmd_work);

}



static int pn533_set_configuration(struct pn533 *dev, u8 cfgitem, u8 *cfgdata,

								u8 cfgdata_len)

{
@@ -2816,7 +2930,8 @@ static int pn533_probe(struct usb_interface *interface, 


	INIT_WORK(&dev->cmd_work, pn533_wq_cmd);

	INIT_WORK(&dev->cmd_complete_work, pn533_wq_cmd_complete);

	INIT_WORK(&dev->mi_work, pn533_wq_mi_recv);

	INIT_WORK(&dev->mi_rx_work, pn533_wq_mi_recv);

	INIT_WORK(&dev->mi_tx_work, pn533_wq_mi_send);

	INIT_WORK(&dev->tg_work, pn533_wq_tg_get_data);

	INIT_WORK(&dev->poll_work, pn533_wq_poll);

	INIT_WORK(&dev->rf_work, pn533_wq_rf);
@@ -2829,6 +2944,7 @@ static int pn533_probe(struct usb_interface *interface, 
	dev->listen_timer.function = pn533_listen_mode_timer;



	skb_queue_head_init(&dev->resp_q);

	skb_queue_head_init(&dev->fragment_skb);



	INIT_LIST_HEAD(&dev->cmd_queue);