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

Commit 22d4aae5 authored by Eric Lapuyade's avatar Eric Lapuyade Committed by Samuel Ortiz
Browse files

NFC: NCI: nci_spi_recv_frame() now returns (not forward) the read frame 



Previously, nci_spi_recv_frame() would directly transmit incoming frames
to the NCI Core. However, it turns out that some NFC NCI Chips will add
additional proprietary headers that must be handled/removed before NCI
Core gets a chance to handle the frame. With this modification, the chip
phy or driver are now responsible to transmit incoming frames to NCI
Core after proper treatment, and NCI SPI becomes a driver helper instead
of sitting between the NFC driver and NCI Core.

As a general rule in NFC, *_recv_frame() APIs are used to deliver an
incoming frame to an upper layer. To better suit the actual purpose of
nci_spi_recv_frame(), and go along with its nci_spi_send()
counterpart, the function is renamed to nci_spi_read()

The skb is returned as the function result

Signed-off-by: default avatarEric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
parent a4ada6ca

include/net/nfc/nci_core.h

+1 −1
Original line number Diff line number Diff line
@@ -233,6 +233,6 @@ struct nci_spi *nci_spi_allocate_spi(struct spi_device *spi, 
				     u8 acknowledge_mode, unsigned int delay,

				     struct nci_dev *ndev);

int nci_spi_send(struct nci_spi *nspi, struct sk_buff *skb);

int nci_spi_recv_frame(struct nci_spi *nspi);

struct sk_buff *nci_spi_read(struct nci_spi *nspi);



#endif /* __NCI_CORE_H */

net/nfc/nci/spi.c

+10 −16
Original line number Diff line number Diff line
@@ -21,7 +21,6 @@ 
#include <linux/export.h>

#include <linux/spi/spi.h>

#include <linux/crc-ccitt.h>

#include <linux/nfc.h>

#include <net/nfc/nci_core.h>



#define NCI_SPI_ACK_SHIFT		6
@@ -164,7 +163,7 @@ static int send_acknowledge(struct nci_spi *nspi, u8 acknowledge) 
	return ret;

}



static struct sk_buff *__nci_spi_recv_frame(struct nci_spi *nspi)

static struct sk_buff *__nci_spi_read(struct nci_spi *nspi)

{

	struct sk_buff *skb;

	struct spi_message m;
@@ -258,7 +257,7 @@ static u8 nci_spi_get_ack(struct sk_buff *skb) 
}



/**

 * nci_spi_recv_frame - receive frame from NCI SPI drivers

 * nci_spi_read - read frame from NCI SPI drivers

 *

 * @nspi: The nci spi

 * Context: can sleep
@@ -266,21 +265,18 @@ static u8 nci_spi_get_ack(struct sk_buff *skb) 
 * This call may only be used from a context that may sleep.  The sleep

 * is non-interruptible, and has no timeout.

 *

 * It returns zero on success, else a negative error code.

 * It returns an allocated skb containing the frame on success, or NULL.

 */

int nci_spi_recv_frame(struct nci_spi *nspi)

struct sk_buff *nci_spi_read(struct nci_spi *nspi)

{

	struct sk_buff *skb;

	int ret = 0;



	nspi->ops->deassert_int(nspi);



	/* Retrieve frame from SPI */

	skb = __nci_spi_recv_frame(nspi);

	if (!skb) {

		ret = -EIO;

	skb = __nci_spi_read(nspi);

	if (!skb)

		goto done;

	}



	if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {

		if (!nci_spi_check_crc(skb)) {
@@ -299,20 +295,18 @@ int nci_spi_recv_frame(struct nci_spi *nspi) 
	/* If there is no payload (ACK/NACK only frame),

	 * free the socket buffer

	 */

	if (skb->len == 0) {

	if (!skb->len) {

		kfree_skb(skb);

		skb = NULL;

		goto done;

	}



	if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED)

		send_acknowledge(nspi, ACKNOWLEDGE_ACK);



	/* Forward skb to NCI core layer */

	ret = nci_recv_frame(nspi->ndev, skb);



done:

	nspi->ops->assert_int(nspi);



	return ret;

	return skb;

}

EXPORT_SYMBOL_GPL(nci_spi_recv_frame);
 
EXPORT_SYMBOL_GPL(nci_spi_read);