NFC: NCI: Simplify NCI SPI to become a simple framing/checking layer

NCI SPI layer should not manage the nci dev, this is the job of the nci
chipset driver. This layer should be limited to frame/deframe nci
packets, and optionnaly check integrity (crc) and manage the ack/nak
protocol.

The NCI SPI must not be mixed up with an NCI dev. spi_[dev|device] are
therefore renamed to a simple spi for more clarity.
The header and crc sizes are moved to nci.h so that drivers can use
them to reserve space in outgoing skbs.
nci_spi_send() is exported to be accessible by drivers.

Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 70 insertions, 155 deletions

diff --git a/include/net/nfc/nci.h b/include/net/nfc/nci.h
index 88785e5c6b2c..e5aa5acafea0 100644
--- a/include/net/nfc/nci.h
+++ b/include/net/nfc/nci.h
@@ -166,6 +166,10 @@
 #define NCI_GID_NFCEE_MGMT                                      0x2
 #define NCI_GID_PROPRIETARY                                     0xf
 
+/* ----- NCI over SPI head/crc(tail) room needed for outgoing frames ----- */
+#define NCI_SPI_HDR_LEN                                         4
+#define NCI_SPI_CRC_LEN                                         2
+
 /* ---- NCI Packet structures ---- */
 #define NCI_CTRL_HDR_SIZE                                       3
 #define NCI_DATA_HDR_SIZE                                       3
diff --git a/include/net/nfc/nci_core.h b/include/net/nfc/nci_core.h
index c08399621c8b..37ba06f2dfa9 100644
--- a/include/net/nfc/nci_core.h
+++ b/include/net/nfc/nci_core.h
@@ -207,16 +207,14 @@ int nci_to_errno(__u8 code);
 #define NCI_SPI_CRC_ENABLED     0x01
 
 /* ----- NCI SPI structures ----- */
-struct nci_spi_dev;
+struct nci_spi;
 
 struct nci_spi_ops {
-        int (*open)(struct nci_spi_dev *nsdev);
-        int (*close)(struct nci_spi_dev *nsdev);
-        void (*assert_int)(struct nci_spi_dev *nsdev);
-        void (*deassert_int)(struct nci_spi_dev *nsdev);
+        void (*assert_int)(struct nci_spi *nspi);
+        void (*deassert_int)(struct nci_spi *nspi);
 };
 
-struct nci_spi_dev {
+struct nci_spi {
         struct nci_dev          *ndev;
         struct spi_device       *spi;
         struct nci_spi_ops      *ops;
@@ -227,31 +225,14 @@ struct nci_spi_dev {
 
         struct completion       req_completion;
         u8                      req_result;
-
-        void                    *driver_data;
 };
 
-/* ----- NCI SPI Devices ----- */
-struct nci_spi_dev *nci_spi_allocate_device(struct spi_device *spi,
-                                                struct nci_spi_ops *ops,
-                                                u32 supported_protocols,
-                                                u32 supported_se,
-                                                u8 acknowledge_mode,
-                                                unsigned int delay);
-void nci_spi_free_device(struct nci_spi_dev *nsdev);
-int nci_spi_register_device(struct nci_spi_dev *nsdev);
-void nci_spi_unregister_device(struct nci_spi_dev *nsdev);
-int nci_spi_recv_frame(struct nci_spi_dev *nsdev);
-
-static inline void nci_spi_set_drvdata(struct nci_spi_dev *nsdev,
-                                            void *data)
-{
-        nsdev->driver_data = data;
-}
-
-static inline void *nci_spi_get_drvdata(struct nci_spi_dev *nsdev)
-{
-        return nsdev->driver_data;
-}
+/* ----- NCI SPI ----- */
+struct nci_spi *nci_spi_allocate_spi(struct spi_device *spi,
+                                     struct nci_spi_ops *ops,
+                                     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);
 
 #endif /* __NCI_CORE_H */
diff --git a/net/nfc/nci/spi.c b/net/nfc/nci/spi.c
index e66fda4d9ede..910dfd8015f4 100644
--- a/net/nfc/nci/spi.c
+++ b/net/nfc/nci/spi.c
@@ -24,8 +24,6 @@
 #include <linux/nfc.h>
 #include <net/nfc/nci_core.h>
 
-#define NCI_SPI_HDR_LEN                 4
-#define NCI_SPI_CRC_LEN                 2
 #define NCI_SPI_ACK_SHIFT               6
 #define NCI_SPI_MSB_PAYLOAD_MASK        0x3F
 
@@ -41,21 +39,7 @@
 
 #define CRC_INIT                0xFFFF
 
-static int nci_spi_open(struct nci_dev *ndev)
-{
-        struct nci_spi_dev *nsdev = nci_get_drvdata(ndev);
-
-        return nsdev->ops->open(nsdev);
-}
-
-static int nci_spi_close(struct nci_dev *ndev)
-{
-        struct nci_spi_dev *nsdev = nci_get_drvdata(ndev);
-
-        return nsdev->ops->close(nsdev);
-}
-
-static int __nci_spi_send(struct nci_spi_dev *nsdev, struct sk_buff *skb)
+static int __nci_spi_send(struct nci_spi *nspi, struct sk_buff *skb)
 {
         struct spi_message m;
         struct spi_transfer t;
@@ -63,32 +47,31 @@ static int __nci_spi_send(struct nci_spi_dev *nsdev, struct sk_buff *skb)
         t.tx_buf = skb->data;
         t.len = skb->len;
         t.cs_change = 0;
-        t.delay_usecs = nsdev->xfer_udelay;
+        t.delay_usecs = nspi->xfer_udelay;
 
         spi_message_init(&m);
         spi_message_add_tail(&t, &m);
 
-        return spi_sync(nsdev->spi, &m);
+        return spi_sync(nspi->spi, &m);
 }
 
-static int nci_spi_send(struct nci_dev *ndev, struct sk_buff *skb)
+int nci_spi_send(struct nci_spi *nspi, struct sk_buff *skb)
 {
-        struct nci_spi_dev *nsdev = nci_get_drvdata(ndev);
         unsigned int payload_len = skb->len;
         unsigned char *hdr;
         int ret;
         long completion_rc;
 
-        nsdev->ops->deassert_int(nsdev);
+        nspi->ops->deassert_int(nspi);
 
         /* add the NCI SPI header to the start of the buffer */
         hdr = skb_push(skb, NCI_SPI_HDR_LEN);
         hdr[0] = NCI_SPI_DIRECT_WRITE;
-        hdr[1] = nsdev->acknowledge_mode;
+        hdr[1] = nspi->acknowledge_mode;
         hdr[2] = payload_len >> 8;
         hdr[3] = payload_len & 0xFF;
 
-        if (nsdev->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+        if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
                 u16 crc;
 
                 crc = crc_ccitt(CRC_INIT, skb->data, skb->len);
@@ -96,123 +79,70 @@ static int nci_spi_send(struct nci_dev *ndev, struct sk_buff *skb)
                 *skb_put(skb, 1) = crc & 0xFF;
         }
 
-        ret = __nci_spi_send(nsdev, skb);
+        ret = __nci_spi_send(nspi, skb);
 
         kfree_skb(skb);
-        nsdev->ops->assert_int(nsdev);
+        nspi->ops->assert_int(nspi);
 
-        if (ret != 0 || nsdev->acknowledge_mode == NCI_SPI_CRC_DISABLED)
+        if (ret != 0 || nspi->acknowledge_mode == NCI_SPI_CRC_DISABLED)
                 goto done;
 
-        init_completion(&nsdev->req_completion);
+        init_completion(&nspi->req_completion);
         completion_rc = wait_for_completion_interruptible_timeout(
-                                                        &nsdev->req_completion,
+                                                        &nspi->req_completion,
                                                         NCI_SPI_SEND_TIMEOUT);