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-rw-r--r--net/nfc/nci/Kconfig11
-rw-r--r--net/nfc/nci/Makefile4
-rw-r--r--net/nfc/nci/core.c77
-rw-r--r--net/nfc/nci/data.c5
-rw-r--r--net/nfc/nci/lib.c3
-rw-r--r--net/nfc/nci/ntf.c10
-rw-r--r--net/nfc/nci/rsp.c3
-rw-r--r--net/nfc/nci/spi.c322
8 files changed, 399 insertions, 36 deletions
diff --git a/net/nfc/nci/Kconfig b/net/nfc/nci/Kconfig
index 6d69b5f0f19..a4f1e42e348 100644
--- a/net/nfc/nci/Kconfig
+++ b/net/nfc/nci/Kconfig
@@ -8,3 +8,14 @@ config NFC_NCI
Say Y here to compile NCI support into the kernel or say M to
compile it as module (nci).
+
+config NFC_NCI_SPI
+ depends on NFC_NCI && SPI
+ select CRC_CCITT
+ bool "NCI over SPI protocol support"
+ default n
+ help
+ NCI (NFC Controller Interface) is a communication protocol between
+ an NFC Controller (NFCC) and a Device Host (DH).
+
+ Say yes if you use an NCI driver that requires SPI link layer.
diff --git a/net/nfc/nci/Makefile b/net/nfc/nci/Makefile
index cdb3a2e4447..7aeedc43187 100644
--- a/net/nfc/nci/Makefile
+++ b/net/nfc/nci/Makefile
@@ -4,4 +4,6 @@
obj-$(CONFIG_NFC_NCI) += nci.o
-nci-objs := core.o data.o lib.o ntf.o rsp.o \ No newline at end of file
+nci-objs := core.o data.o lib.o ntf.o rsp.o
+
+nci-$(CONFIG_NFC_NCI_SPI) += spi.o
diff --git a/net/nfc/nci/core.c b/net/nfc/nci/core.c
index 5f98dc1bf03..2b400e1a869 100644
--- a/net/nfc/nci/core.c
+++ b/net/nfc/nci/core.c
@@ -20,8 +20,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
@@ -75,7 +74,7 @@ static int __nci_request(struct nci_dev *ndev,
ndev->req_status = NCI_REQ_PEND;
- init_completion(&ndev->req_completion);
+ reinit_completion(&ndev->req_completion);
req(ndev, opt);
completion_rc =
wait_for_completion_interruptible_timeout(&ndev->req_completion,
@@ -302,6 +301,9 @@ static int nci_open_device(struct nci_dev *ndev)
rc = __nci_request(ndev, nci_reset_req, 0,
msecs_to_jiffies(NCI_RESET_TIMEOUT));
+ if (ndev->ops->setup)
+ ndev->ops->setup(ndev);
+
if (!rc) {
rc = __nci_request(ndev, nci_init_req, 0,
msecs_to_jiffies(NCI_INIT_TIMEOUT));
@@ -362,6 +364,8 @@ static int nci_close_device(struct nci_dev *ndev)
msecs_to_jiffies(NCI_RESET_TIMEOUT));
clear_bit(NCI_INIT, &ndev->flags);
+ del_timer_sync(&ndev->cmd_timer);
+
/* Flush cmd wq */
flush_workqueue(ndev->cmd_wq);
@@ -409,12 +413,26 @@ static int nci_dev_down(struct nfc_dev *nfc_dev)
return nci_close_device(ndev);
}
+int nci_set_config(struct nci_dev *ndev, __u8 id, size_t len, __u8 *val)
+{
+ struct nci_set_config_param param;
+
+ if (!val || !len)
+ return 0;
+
+ param.id = id;
+ param.len = len;
+ param.val = val;
+
+ return __nci_request(ndev, nci_set_config_req, (unsigned long)&param,
+ msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
+}
+EXPORT_SYMBOL(nci_set_config);
+
static int nci_set_local_general_bytes(struct nfc_dev *nfc_dev)
{
struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
struct nci_set_config_param param;
- __u8 local_gb[NFC_MAX_GT_LEN];
- int i;
param.val = nfc_get_local_general_bytes(nfc_dev, &param.len);
if ((param.val == NULL) || (param.len == 0))
@@ -423,11 +441,7 @@ static int nci_set_local_general_bytes(struct nfc_dev *nfc_dev)
if (param.len > NFC_MAX_GT_LEN)
return -EINVAL;
- for (i = 0; i < param.len; i++)
- local_gb[param.len-1-i] = param.val[i];
-
param.id = NCI_PN_ATR_REQ_GEN_BYTES;
- param.val = local_gb;
return nci_request(ndev, nci_set_config_req, (unsigned long)&param,
msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
@@ -636,6 +650,21 @@ static int nci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
return rc;
}
+static int nci_enable_se(struct nfc_dev *nfc_dev, u32 se_idx)
+{
+ return 0;
+}
+
+static int nci_disable_se(struct nfc_dev *nfc_dev, u32 se_idx)
+{
+ return 0;
+}
+
+static int nci_discover_se(struct nfc_dev *nfc_dev)
+{
+ return 0;
+}
+
static struct nfc_ops nci_nfc_ops = {
.dev_up = nci_dev_up,
.dev_down = nci_dev_down,
@@ -646,6 +675,9 @@ static struct nfc_ops nci_nfc_ops = {
.activate_target = nci_activate_target,
.deactivate_target = nci_deactivate_target,
.im_transceive = nci_transceive,
+ .enable_se = nci_enable_se,
+ .disable_se = nci_disable_se,
+ .discover_se = nci_discover_se,
};
/* ---- Interface to NCI drivers ---- */
@@ -677,6 +709,7 @@ struct nci_dev *nci_allocate_device(struct nci_ops *ops,
ndev->ops = ops;
ndev->tx_headroom = tx_headroom;
ndev->tx_tailroom = tx_tailroom;
+ init_completion(&ndev->req_completion);
ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
supported_protocols,
@@ -795,12 +828,11 @@ EXPORT_SYMBOL(nci_unregister_device);
/**
* nci_recv_frame - receive frame from NCI drivers
*
+ * @ndev: The nci device
* @skb: The sk_buff to receive
*/
-int nci_recv_frame(struct sk_buff *skb)
+int nci_recv_frame(struct nci_dev *ndev, struct sk_buff *skb)
{
- struct nci_dev *ndev = (struct nci_dev *) skb->dev;
-
pr_debug("len %d\n", skb->len);
if (!ndev || (!test_bit(NCI_UP, &ndev->flags) &&
@@ -817,10 +849,8 @@ int nci_recv_frame(struct sk_buff *skb)
}
EXPORT_SYMBOL(nci_recv_frame);
-static int nci_send_frame(struct sk_buff *skb)
+static int nci_send_frame(struct nci_dev *ndev, struct sk_buff *skb)
{
- struct nci_dev *ndev = (struct nci_dev *) skb->dev;
-
pr_debug("len %d\n", skb->len);
if (!ndev) {
@@ -831,7 +861,11 @@ static int nci_send_frame(struct sk_buff *skb)
/* Get rid of skb owner, prior to sending to the driver. */
skb_orphan(skb);
- return ndev->ops->send(skb);
+ /* Send copy to sniffer */
+ nfc_send_to_raw_sock(ndev->nfc_dev, skb,
+ RAW_PAYLOAD_NCI, NFC_DIRECTION_TX);
+
+ return ndev->ops->send(ndev, skb);
}
/* Send NCI command */
@@ -859,8 +893,6 @@ int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
if (plen)
memcpy(skb_put(skb, plen), payload, plen);
- skb->dev = (void *) ndev;
-
skb_queue_tail(&ndev->cmd_q, skb);
queue_work(ndev->cmd_wq, &ndev->cmd_work);
@@ -892,7 +924,7 @@ static void nci_tx_work(struct work_struct *work)
nci_conn_id(skb->data),
nci_plen(skb->data));
- nci_send_frame(skb);
+ nci_send_frame(ndev, skb);
mod_timer(&ndev->data_timer,
jiffies + msecs_to_jiffies(NCI_DATA_TIMEOUT));
@@ -907,6 +939,11 @@ static void nci_rx_work(struct work_struct *work)
struct sk_buff *skb;
while ((skb = skb_dequeue(&ndev->rx_q))) {
+
+ /* Send copy to sniffer */
+ nfc_send_to_raw_sock(ndev->nfc_dev, skb,
+ RAW_PAYLOAD_NCI, NFC_DIRECTION_RX);
+
/* Process frame */
switch (nci_mt(skb->data)) {
case NCI_MT_RSP_PKT:
@@ -961,7 +998,7 @@ static void nci_cmd_work(struct work_struct *work)
nci_opcode_oid(nci_opcode(skb->data)),
nci_plen(skb->data));
- nci_send_frame(skb);
+ nci_send_frame(ndev, skb);
mod_timer(&ndev->cmd_timer,
jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c
index 76c48c5324f..6c3aef85287 100644
--- a/net/nfc/nci/data.c
+++ b/net/nfc/nci/data.c
@@ -16,8 +16,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
@@ -80,8 +79,6 @@ static inline void nci_push_data_hdr(struct nci_dev *ndev,
nci_mt_set((__u8 *)hdr, NCI_MT_DATA_PKT);
nci_pbf_set((__u8 *)hdr, pbf);
-
- skb->dev = (void *) ndev;
}
static int nci_queue_tx_data_frags(struct nci_dev *ndev,
diff --git a/net/nfc/nci/lib.c b/net/nfc/nci/lib.c
index 6b7fd26c68d..ed774a2e989 100644
--- a/net/nfc/nci/lib.c
+++ b/net/nfc/nci/lib.c
@@ -20,8 +20,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c
index b2aa98ef092..f8f6af23138 100644
--- a/net/nfc/nci/ntf.c
+++ b/net/nfc/nci/ntf.c
@@ -20,8 +20,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
@@ -367,7 +366,6 @@ static int nci_extract_activation_params_nfc_dep(struct nci_dev *ndev,
struct nci_rf_intf_activated_ntf *ntf, __u8 *data)
{
struct activation_params_poll_nfc_dep *poll;
- int i;
switch (ntf->activation_rf_tech_and_mode) {
case NCI_NFC_A_PASSIVE_POLL_MODE:
@@ -375,10 +373,8 @@ static int nci_extract_activation_params_nfc_dep(struct nci_dev *ndev,
poll = &ntf->activation_params.poll_nfc_dep;
poll->atr_res_len = min_t(__u8, *data++, 63);
pr_debug("atr_res_len %d\n", poll->atr_res_len);
- if (poll->atr_res_len > 0) {
- for (i = 0; i < poll->atr_res_len; i++)
- poll->atr_res[poll->atr_res_len-1-i] = data[i];
- }
+ if (poll->atr_res_len > 0)
+ memcpy(poll->atr_res, data, poll->atr_res_len);
break;
default:
diff --git a/net/nfc/nci/rsp.c b/net/nfc/nci/rsp.c
index dd072f38ad0..041de51ccdb 100644
--- a/net/nfc/nci/rsp.c
+++ b/net/nfc/nci/rsp.c
@@ -20,8 +20,7 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
diff --git a/net/nfc/nci/spi.c b/net/nfc/nci/spi.c
new file mode 100644
index 00000000000..ec250e77763
--- /dev/null
+++ b/net/nfc/nci/spi.c
@@ -0,0 +1,322 @@
+/*
+ * Copyright (C) 2013 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#define pr_fmt(fmt) "nci_spi: %s: " fmt, __func__
+
+#include <linux/export.h>
+#include <linux/spi/spi.h>
+#include <linux/crc-ccitt.h>
+#include <net/nfc/nci_core.h>
+
+#define NCI_SPI_ACK_SHIFT 6
+#define NCI_SPI_MSB_PAYLOAD_MASK 0x3F
+
+#define NCI_SPI_SEND_TIMEOUT (NCI_CMD_TIMEOUT > NCI_DATA_TIMEOUT ? \
+ NCI_CMD_TIMEOUT : NCI_DATA_TIMEOUT)
+
+#define NCI_SPI_DIRECT_WRITE 0x01
+#define NCI_SPI_DIRECT_READ 0x02
+
+#define ACKNOWLEDGE_NONE 0
+#define ACKNOWLEDGE_ACK 1
+#define ACKNOWLEDGE_NACK 2
+
+#define CRC_INIT 0xFFFF
+
+static int __nci_spi_send(struct nci_spi *nspi, struct sk_buff *skb,
+ int cs_change)
+{
+ struct spi_message m;
+ struct spi_transfer t;
+
+ memset(&t, 0, sizeof(struct spi_transfer));
+ /* a NULL skb means we just want the SPI chip select line to raise */
+ if (skb) {
+ t.tx_buf = skb->data;
+ t.len = skb->len;
+ } else {
+ /* still set tx_buf non NULL to make the driver happy */
+ t.tx_buf = &t;
+ t.len = 0;
+ }
+ t.cs_change = cs_change;
+ t.delay_usecs = nspi->xfer_udelay;
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+
+ return spi_sync(nspi->spi, &m);
+}
+
+int nci_spi_send(struct nci_spi *nspi,
+ struct completion *write_handshake_completion,
+ struct sk_buff *skb)
+{
+ unsigned int payload_len = skb->len;
+ unsigned char *hdr;
+ int ret;
+ long completion_rc;
+
+ /* 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] = nspi->acknowledge_mode;
+ hdr[2] = payload_len >> 8;
+ hdr[3] = payload_len & 0xFF;
+
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ u16 crc;
+
+ crc = crc_ccitt(CRC_INIT, skb->data, skb->len);
+ *skb_put(skb, 1) = crc >> 8;
+ *skb_put(skb, 1) = crc & 0xFF;
+ }
+
+ if (write_handshake_completion) {
+ /* Trick SPI driver to raise chip select */
+ ret = __nci_spi_send(nspi, NULL, 1);
+ if (ret)
+ goto done;
+
+ /* wait for NFC chip hardware handshake to complete */
+ if (wait_for_completion_timeout(write_handshake_completion,
+ msecs_to_jiffies(1000)) == 0) {
+ ret = -ETIME;
+ goto done;
+ }
+ }
+
+ ret = __nci_spi_send(nspi, skb, 0);
+ if (ret != 0 || nspi->acknowledge_mode == NCI_SPI_CRC_DISABLED)
+ goto done;
+
+ reinit_completion(&nspi->req_completion);
+ completion_rc = wait_for_completion_interruptible_timeout(
+ &nspi->req_completion,
+ NCI_SPI_SEND_TIMEOUT);
+
+ if (completion_rc <= 0 || nspi->req_result == ACKNOWLEDGE_NACK)
+ ret = -EIO;
+
+done:
+ kfree_skb(skb);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(nci_spi_send);
+
+/* ---- Interface to NCI SPI drivers ---- */
+
+/**
+ * nci_spi_allocate_spi - allocate a new nci spi
+ *
+ * @spi: SPI device
+ * @acknowledge_mode: Acknowledge mode used by the NFC device
+ * @delay: delay between transactions in us
+ * @ndev: nci dev to send incoming nci frames to
+ */
+struct nci_spi *nci_spi_allocate_spi(struct spi_device *spi,
+ u8 acknowledge_mode, unsigned int delay,
+ struct nci_dev *ndev)
+{
+ struct nci_spi *nspi;
+
+ nspi = devm_kzalloc(&spi->dev, sizeof(struct nci_spi), GFP_KERNEL);
+ if (!nspi)
+ return NULL;
+
+ nspi->acknowledge_mode = acknowledge_mode;
+ nspi->xfer_udelay = delay;
+
+ nspi->spi = spi;
+ nspi->ndev = ndev;
+ init_completion(&nspi->req_completion);
+
+ return nspi;
+}
+EXPORT_SYMBOL_GPL(nci_spi_allocate_spi);
+
+static int send_acknowledge(struct nci_spi *nspi, u8 acknowledge)
+{
+ struct sk_buff *skb;
+ unsigned char *hdr;
+ u16 crc;
+ int ret;
+
+ skb = nci_skb_alloc(nspi->ndev, 0, GFP_KERNEL);
+
+ /* 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] = NCI_SPI_CRC_ENABLED;
+ hdr[2] = acknowledge << NCI_SPI_ACK_SHIFT;
+ hdr[3] = 0;
+
+ crc = crc_ccitt(CRC_INIT, skb->data, skb->len);
+ *skb_put(skb, 1) = crc >> 8;
+ *skb_put(skb, 1) = crc & 0xFF;
+
+ ret = __nci_spi_send(nspi, skb, 0);
+
+ kfree_skb(skb);
+
+ return ret;
+}
+
+static struct sk_buff *__nci_spi_read(struct nci_spi *nspi)
+{
+ struct sk_buff *skb;
+ struct spi_message m;
+ unsigned char req[2], resp_hdr[2];
+ struct spi_transfer tx, rx;
+ unsigned short rx_len = 0;
+ int ret;
+
+ spi_message_init(&m);
+
+ memset(&tx, 0, sizeof(struct spi_transfer));
+ req[0] = NCI_SPI_DIRECT_READ;
+ req[1] = nspi->acknowledge_mode;
+ tx.tx_buf = req;
+ tx.len = 2;
+ tx.cs_change = 0;
+ spi_message_add_tail(&tx, &m);
+
+ memset(&rx, 0, sizeof(struct spi_transfer));
+ rx.rx_buf = resp_hdr;
+ rx.len = 2;
+ rx.cs_change = 1;
+ spi_message_add_tail(&rx, &m);
+
+ ret = spi_sync(nspi->spi, &m);
+ if (ret)
+ return NULL;
+
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED)
+ rx_len = ((resp_hdr[0] & NCI_SPI_MSB_PAYLOAD_MASK) << 8) +
+ resp_hdr[1] + NCI_SPI_CRC_LEN;
+ else
+ rx_len = (resp_hdr[0] << 8) | resp_hdr[1];
+
+ skb = nci_skb_alloc(nspi->ndev, rx_len, GFP_KERNEL);
+ if (!skb)
+ return NULL;
+
+ spi_message_init(&m);
+
+ memset(&rx, 0, sizeof(struct spi_transfer));
+ rx.rx_buf = skb_put(skb, rx_len);
+ rx.len = rx_len;
+ rx.cs_change = 0;
+ rx.delay_usecs = nspi->xfer_udelay;
+ spi_message_add_tail(&rx, &m);
+
+ ret = spi_sync(nspi->spi, &m);
+ if (ret)
+ goto receive_error;
+
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ *skb_push(skb, 1) = resp_hdr[1];
+ *skb_push(skb, 1) = resp_hdr[0];
+ }
+
+ return skb;
+
+receive_error:
+ kfree_skb(skb);
+
+ return NULL;
+}
+
+static int nci_spi_check_crc(struct sk_buff *skb)
+{
+ u16 crc_data = (skb->data[skb->len - 2] << 8) |
+ skb->data[skb->len - 1];
+ int ret;
+
+ ret = (crc_ccitt(CRC_INIT, skb->data, skb->len - NCI_SPI_CRC_LEN)
+ == crc_data);
+
+ skb_trim(skb, skb->len - NCI_SPI_CRC_LEN);
+
+ return ret;
+}
+
+static u8 nci_spi_get_ack(struct sk_buff *skb)
+{
+ u8 ret;
+
+ ret = skb->data[0] >> NCI_SPI_ACK_SHIFT;
+
+ /* Remove NFCC part of the header: ACK, NACK and MSB payload len */
+ skb_pull(skb, 2);
+
+ return ret;
+}
+
+/**
+ * nci_spi_read - read frame from NCI SPI drivers
+ *
+ * @nspi: The nci spi
+ * Context: can sleep
+ *
+ * This call may only be used from a context that may sleep. The sleep
+ * is non-interruptible, and has no timeout.
+ *
+ * It returns an allocated skb containing the frame on success, or NULL.
+ */
+struct sk_buff *nci_spi_read(struct nci_spi *nspi)
+{
+ struct sk_buff *skb;
+
+ /* Retrieve frame from SPI */
+ skb = __nci_spi_read(nspi);
+ if (!skb)
+ goto done;
+
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED) {
+ if (!nci_spi_check_crc(skb)) {
+ send_acknowledge(nspi, ACKNOWLEDGE_NACK);
+ goto done;
+ }
+
+ /* In case of acknowledged mode: if ACK or NACK received,
+ * unblock completion of latest frame sent.
+ */
+ nspi->req_result = nci_spi_get_ack(skb);
+ if (nspi->req_result)
+ complete(&nspi->req_completion);
+ }
+
+ /* If there is no payload (ACK/NACK only frame),
+ * free the socket buffer
+ */
+ if (!skb->len) {
+ kfree_skb(skb);
+ skb = NULL;
+ goto done;
+ }
+
+ if (nspi->acknowledge_mode == NCI_SPI_CRC_ENABLED)
+ send_acknowledge(nspi, ACKNOWLEDGE_ACK);
+
+done:
+
+ return skb;
+}
+EXPORT_SYMBOL_GPL(nci_spi_read);