path: root/net/nfc
diff options
authorEric Lapuyade <eric.lapuyade@linux.intel.com>2013-09-23 17:56:31 +0200
committerSamuel Ortiz <sameo@linux.intel.com>2013-09-25 14:25:41 +0200
commit22d4aae5897fb8355130b8f7d9a3af153eac9714 (patch)
treeb11eb743ff1f9a816875b43237ae51f28695b421 /net/nfc
parenta4ada6cadb8a2246f263ff6a0d0cca8832f3970e (diff)
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: Eric Lapuyade <eric.lapuyade@intel.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'net/nfc')
1 files changed, 10 insertions, 16 deletions
diff --git a/net/nfc/nci/spi.c b/net/nfc/nci/spi.c
index c111506b36d1..734c6dde7751 100644
--- a/net/nfc/nci/spi.c
+++ b/net/nfc/nci/spi.c
@@ -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>
@@ -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;
/* 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) {
+ 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);
- return ret;
+ return skb;

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