diff options
Diffstat (limited to 'net/nfc/nci')
-rw-r--r-- | net/nfc/nci/Kconfig | 10 | ||||
-rw-r--r-- | net/nfc/nci/Makefile | 4 | ||||
-rw-r--r-- | net/nfc/nci/core.c | 37 | ||||
-rw-r--r-- | net/nfc/nci/data.c | 2 | ||||
-rw-r--r-- | net/nfc/nci/spi.c | 378 |
5 files changed, 415 insertions, 16 deletions
diff --git a/net/nfc/nci/Kconfig b/net/nfc/nci/Kconfig index 6d69b5f..2a24160 100644 --- a/net/nfc/nci/Kconfig +++ b/net/nfc/nci/Kconfig @@ -8,3 +8,13 @@ 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 + 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 cdb3a2e..7aeedc4 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 48ada0e..b943d46 100644 --- a/net/nfc/nci/core.c +++ b/net/nfc/nci/core.c @@ -636,6 +636,21 @@ 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 +661,9 @@ 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 ---- */ @@ -658,7 +676,6 @@ static struct nfc_ops nci_nfc_ops = { */ struct nci_dev *nci_allocate_device(struct nci_ops *ops, __u32 supported_protocols, - __u32 supported_se, int tx_headroom, int tx_tailroom) { struct nci_dev *ndev; @@ -681,7 +698,6 @@ struct nci_dev *nci_allocate_device(struct nci_ops *ops, ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops, supported_protocols, - supported_se, tx_headroom + NCI_DATA_HDR_SIZE, tx_tailroom); if (!ndev->nfc_dev) @@ -797,12 +813,11 @@ 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) && @@ -819,10 +834,8 @@ 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) { @@ -833,7 +846,7 @@ 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); + return ndev->ops->send(ndev, skb); } /* Send NCI command */ @@ -861,8 +874,6 @@ 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); @@ -894,7 +905,7 @@ 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)); @@ -963,7 +974,7 @@ 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 76c48c5..2a9399d 100644 --- a/net/nfc/nci/data.c +++ b/net/nfc/nci/data.c @@ -80,8 +80,6 @@ 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/spi.c b/net/nfc/nci/spi.c new file mode 100644 index 0000000..c7cf37b --- /dev/null +++ b/net/nfc/nci/spi.c @@ -0,0 +1,378 @@ +/* + * 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 <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 + +#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_open(struct nci_dev *nci_dev) +{ + struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev); + + return ndev->ops->open(ndev); +} + +static int nci_spi_close(struct nci_dev *nci_dev) +{ + struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev); + + return ndev->ops->close(ndev); +} + +static int __nci_spi_send(struct nci_spi_dev *ndev, struct sk_buff *skb) +{ + struct spi_message m; + struct spi_transfer t; + + t.tx_buf = skb->data; + t.len = skb->len; + t.cs_change = 0; + t.delay_usecs = ndev->xfer_udelay; + + spi_message_init(&m); + spi_message_add_tail(&t, &m); + + return spi_sync(ndev->spi, &m); +} + +static int nci_spi_send(struct nci_dev *nci_dev, struct sk_buff *skb) +{ + struct nci_spi_dev *ndev = nci_get_drvdata(nci_dev); + unsigned int payload_len = skb->len; + unsigned char *hdr; + int ret; + long completion_rc; + + ndev->ops->deassert_int(ndev); + + /* 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] = ndev->acknowledge_mode; + hdr[2] = payload_len >> 8; + hdr[3] = payload_len & 0xFF; + + if (ndev->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; + } + + ret = __nci_spi_send(ndev, skb); + + kfree_skb(skb); + ndev->ops->assert_int(ndev); + + if (ret != 0 || ndev->acknowledge_mode == NCI_SPI_CRC_DISABLED) + goto done; + + init_completion(&ndev->req_completion); + completion_rc = + wait_for_completion_interruptible_timeout(&ndev->req_completion, + NCI_SPI_SEND_TIMEOUT); + + if (completion_rc <= 0 || ndev->req_result == ACKNOWLEDGE_NACK) + ret = -EIO; + +done: + return ret; +} + +static struct nci_ops nci_spi_ops = { + .open = nci_spi_open, + .close = nci_spi_close, + .send = nci_spi_send, +}; + +/* ---- Interface to NCI SPI drivers ---- */ + +/** + * nci_spi_allocate_device - allocate a new nci spi device + * + * @spi: SPI device + * @ops: device operations + * @supported_protocols: NFC protocols supported by the device + * @supported_se: NFC Secure Elements supported by the device + * @acknowledge_mode: Acknowledge mode used by the device + * @delay: delay between transactions in us + */ +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) +{ + struct nci_spi_dev *ndev; + int tailroom = 0; + + if (!ops->open || !ops->close || !ops->assert_int || !ops->deassert_int) + return NULL; + + if (!supported_protocols) + return NULL; + + ndev = devm_kzalloc(&spi->dev, sizeof(struct nci_dev), GFP_KERNEL); + if (!ndev) + return NULL; + + ndev->ops = ops; + ndev->acknowledge_mode = acknowledge_mode; + ndev->xfer_udelay = delay; + + if (acknowledge_mode == NCI_SPI_CRC_ENABLED) + tailroom += NCI_SPI_CRC_LEN; + + ndev->nci_dev = nci_allocate_device(&nci_spi_ops, supported_protocols, + NCI_SPI_HDR_LEN, tailroom); + if (!ndev->nci_dev) + return NULL; + + nci_set_drvdata(ndev->nci_dev, ndev); + + return ndev; +} +EXPORT_SYMBOL_GPL(nci_spi_allocate_device); + +/** + * nci_spi_free_device - deallocate nci spi device + * + * @ndev: The nci spi device to deallocate + */ +void nci_spi_free_device(struct nci_spi_dev *ndev) +{ + nci_free_device(ndev->nci_dev); +} +EXPORT_SYMBOL_GPL(nci_spi_free_device); + +/** + * nci_spi_register_device - register a nci spi device in the nfc subsystem + * + * @pdev: The nci spi device to register + */ +int nci_spi_register_device(struct nci_spi_dev *ndev) +{ + return nci_register_device(ndev->nci_dev); +} +EXPORT_SYMBOL_GPL(nci_spi_register_device); + +/** + * nci_spi_unregister_device - unregister a nci spi device in the nfc subsystem + * + * @dev: The nci spi device to unregister + */ +void nci_spi_unregister_device(struct nci_spi_dev *ndev) +{ + nci_unregister_device(ndev->nci_dev); +} +EXPORT_SYMBOL_GPL(nci_spi_unregister_device); + +static int send_acknowledge(struct nci_spi_dev *ndev, u8 acknowledge) +{ + struct sk_buff *skb; + unsigned char *hdr; + u16 crc; + int ret; + + skb = nci_skb_alloc(ndev->nci_dev, 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(ndev, skb); + + kfree_skb(skb); + + return ret; +} + +static struct sk_buff *__nci_spi_recv_frame(struct nci_spi_dev *ndev) +{ + 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); + req[0] = NCI_SPI_DIRECT_READ; + req[1] = ndev->acknowledge_mode; + tx.tx_buf = req; + tx.len = 2; + tx.cs_change = 0; + spi_message_add_tail(&tx, &m); + rx.rx_buf = resp_hdr; + rx.len = 2; + rx.cs_change = 1; + spi_message_add_tail(&rx, &m); + ret = spi_sync(ndev->spi, &m); + + if (ret) + return NULL; + + if (ndev->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(ndev->nci_dev, rx_len, GFP_KERNEL); + if (!skb) + return NULL; + + spi_message_init(&m); + rx.rx_buf = skb_put(skb, rx_len); + rx.len = rx_len; + rx.cs_change = 0; + rx.delay_usecs = ndev->xfer_udelay; + spi_message_add_tail(&rx, &m); + ret = spi_sync(ndev->spi, &m); + + if (ret) + goto receive_error; + + if (ndev->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_recv_frame - receive frame from NCI SPI drivers + * + * @ndev: The nci spi device + * 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 zero on success, else a negative error code. + */ +int nci_spi_recv_frame(struct nci_spi_dev *ndev) +{ + struct sk_buff *skb; + int ret = 0; + + ndev->ops->deassert_int(ndev); + + /* Retrieve frame from SPI */ + skb = __nci_spi_recv_frame(ndev); + if (!skb) { + ret = -EIO; + goto done; + } + + if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED) { + if (!nci_spi_check_crc(skb)) { + send_acknowledge(ndev, ACKNOWLEDGE_NACK); + goto done; + } + + /* In case of acknowledged mode: if ACK or NACK received, + * unblock completion of latest frame sent. + */ + ndev->req_result = nci_spi_get_ack(skb); + if (ndev->req_result) + complete(&ndev->req_completion); + } + + /* If there is no payload (ACK/NACK only frame), + * free the socket buffer + */ + if (skb->len == 0) { + kfree_skb(skb); + goto done; + } + + if (ndev->acknowledge_mode == NCI_SPI_CRC_ENABLED) + send_acknowledge(ndev, ACKNOWLEDGE_ACK); + + /* Forward skb to NCI core layer */ + ret = nci_recv_frame(ndev->nci_dev, skb); + +done: + ndev->ops->assert_int(ndev); + + return ret; +} +EXPORT_SYMBOL_GPL(nci_spi_recv_frame); |