From 93aead46428d38729f430f395a8403795a019e54 Mon Sep 17 00:00:00 2001 From: Ilan Elias Date: Sun, 18 Sep 2011 11:19:36 +0300 Subject: NFC: driver for TI shared transport Signed-off-by: Ilan Elias Signed-off-by: John W. Linville --- drivers/nfc/nfcwilink.c | 342 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 342 insertions(+) create mode 100644 drivers/nfc/nfcwilink.c (limited to 'drivers/nfc/nfcwilink.c') diff --git a/drivers/nfc/nfcwilink.c b/drivers/nfc/nfcwilink.c new file mode 100644 index 0000000..5b0f1ff --- /dev/null +++ b/drivers/nfc/nfcwilink.c @@ -0,0 +1,342 @@ +/* + * Texas Instrument's NFC Driver For Shared Transport. + * + * NFC Driver acts as interface between NCI core and + * TI Shared Transport Layer. + * + * Copyright (C) 2011 Texas Instruments, Inc. + * + * Written by Ilan Elias + * + * Acknowledgements: + * This file is based on btwilink.c, which was written + * by Raja Mani and Pavan Savoy. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ +#include +#include +#include +#include +#include + +#define NFCWILINK_CHNL 12 +#define NFCWILINK_OPCODE 7 +#define NFCWILINK_MAX_FRAME_SIZE 300 +#define NFCWILINK_HDR_LEN 4 +#define NFCWILINK_OFFSET_LEN_IN_HDR 1 +#define NFCWILINK_LEN_SIZE 2 +#define NFCWILINK_REGISTER_TIMEOUT 8000 /* 8 sec */ + +struct nfcwilink_hdr { + u8 chnl; + u8 opcode; + u16 len; +} __packed; + +struct nfcwilink { + struct platform_device *pdev; + struct nci_dev *ndev; + unsigned long flags; + + char st_register_cb_status; + long (*st_write) (struct sk_buff *); + struct completion st_register_completed; +}; + +/* NFCWILINK driver flags */ +enum { + NFCWILINK_RUNNING, +}; + +/* Called by ST when registration is complete */ +static void nfcwilink_register_complete(void *priv_data, char data) +{ + struct nfcwilink *drv = priv_data; + + nfc_dev_dbg(&drv->pdev->dev, "register_complete entry"); + + /* store ST registration status */ + drv->st_register_cb_status = data; + + /* complete the wait in nfc_st_open() */ + complete(&drv->st_register_completed); +} + +/* Called by ST when receive data is available */ +static long nfcwilink_receive(void *priv_data, struct sk_buff *skb) +{ + struct nfcwilink *drv = priv_data; + int rc; + + nfc_dev_dbg(&drv->pdev->dev, "receive entry, len %d", skb->len); + + if (!skb) + return -EFAULT; + + if (!drv) { + kfree_skb(skb); + return -EFAULT; + } + + /* strip the ST header + (apart for the chnl byte, which is not received in the hdr) */ + skb_pull(skb, (NFCWILINK_HDR_LEN-1)); + + skb->dev = (void *) drv->ndev; + + /* Forward skb to NCI core layer */ + rc = nci_recv_frame(skb); + if (rc < 0) { + nfc_dev_err(&drv->pdev->dev, "nci_recv_frame failed %d", rc); + return rc; + } + + return 0; +} + +/* protocol structure registered with ST */ +static struct st_proto_s nfcwilink_proto = { + .chnl_id = NFCWILINK_CHNL, + .max_frame_size = NFCWILINK_MAX_FRAME_SIZE, + .hdr_len = (NFCWILINK_HDR_LEN-1), /* not including chnl byte */ + .offset_len_in_hdr = NFCWILINK_OFFSET_LEN_IN_HDR, + .len_size = NFCWILINK_LEN_SIZE, + .reserve = 0, + .recv = nfcwilink_receive, + .reg_complete_cb = nfcwilink_register_complete, + .write = NULL, +}; + +static int nfcwilink_open(struct nci_dev *ndev) +{ + struct nfcwilink *drv = nci_get_drvdata(ndev); + unsigned long comp_ret; + int rc; + + nfc_dev_dbg(&drv->pdev->dev, "open entry"); + + if (test_and_set_bit(NFCWILINK_RUNNING, &drv->flags)) { + rc = -EBUSY; + goto exit; + } + + nfcwilink_proto.priv_data = drv; + + init_completion(&drv->st_register_completed); + drv->st_register_cb_status = -EINPROGRESS; + + rc = st_register(&nfcwilink_proto); + if (rc < 0) { + if (rc == -EINPROGRESS) { + comp_ret = wait_for_completion_timeout( + &drv->st_register_completed, + msecs_to_jiffies(NFCWILINK_REGISTER_TIMEOUT)); + + nfc_dev_dbg(&drv->pdev->dev, + "wait_for_completion_timeout returned %ld", + comp_ret); + + if (comp_ret == 0) { + /* timeout */ + rc = -ETIMEDOUT; + goto clear_exit; + } else if (drv->st_register_cb_status != 0) { + rc = drv->st_register_cb_status; + nfc_dev_err(&drv->pdev->dev, + "st_register_cb failed %d", rc); + goto clear_exit; + } + } else { + nfc_dev_err(&drv->pdev->dev, + "st_register failed %d", rc); + goto clear_exit; + } + } + + /* st_register MUST fill the write callback */ + BUG_ON(nfcwilink_proto.write == NULL); + drv->st_write = nfcwilink_proto.write; + + goto exit; + +clear_exit: + clear_bit(NFCWILINK_RUNNING, &drv->flags); + +exit: + return rc; +} + +static int nfcwilink_close(struct nci_dev *ndev) +{ + struct nfcwilink *drv = nci_get_drvdata(ndev); + int rc; + + nfc_dev_dbg(&drv->pdev->dev, "close entry"); + + if (!test_and_clear_bit(NFCWILINK_RUNNING, &drv->flags)) + return 0; + + rc = st_unregister(&nfcwilink_proto); + if (rc) + nfc_dev_err(&drv->pdev->dev, "st_unregister failed %d", rc); + + drv->st_write = NULL; + + return rc; +} + +static int nfcwilink_send(struct sk_buff *skb) +{ + struct nci_dev *ndev = (struct nci_dev *)skb->dev; + struct nfcwilink *drv = nci_get_drvdata(ndev); + struct nfcwilink_hdr hdr = {NFCWILINK_CHNL, NFCWILINK_OPCODE, 0x0000}; + long len; + + nfc_dev_dbg(&drv->pdev->dev, "send entry, len %d", skb->len); + + if (!test_bit(NFCWILINK_RUNNING, &drv->flags)) + return -EBUSY; + + /* add the ST hdr to the start of the buffer */ + hdr.len = skb->len; + memcpy(skb_push(skb, NFCWILINK_HDR_LEN), &hdr, NFCWILINK_HDR_LEN); + + /* Insert skb to shared transport layer's transmit queue. + * Freeing skb memory is taken care in shared transport layer, + * so don't free skb memory here. + */ + len = drv->st_write(skb); + if (len < 0) { + kfree_skb(skb); + nfc_dev_err(&drv->pdev->dev, "st_write failed %ld", len); + return -EFAULT; + } + + return 0; +} + +static struct nci_ops nfcwilink_ops = { + .open = nfcwilink_open, + .close = nfcwilink_close, + .send = nfcwilink_send, +}; + +static int nfcwilink_probe(struct platform_device *pdev) +{ + static struct nfcwilink *drv; + int rc; + u32 protocols; + + nfc_dev_dbg(&pdev->dev, "probe entry"); + + drv = kzalloc(sizeof(struct nfcwilink), GFP_KERNEL); + if (!drv) { + rc = -ENOMEM; + goto exit; + } + + drv->pdev = pdev; + + protocols = NFC_PROTO_JEWEL_MASK + | NFC_PROTO_MIFARE_MASK | NFC_PROTO_FELICA_MASK + | NFC_PROTO_ISO14443_MASK + | NFC_PROTO_NFC_DEP_MASK; + + drv->ndev = nci_allocate_device(&nfcwilink_ops, + protocols, + NFCWILINK_HDR_LEN, + 0); + if (!drv->ndev) { + nfc_dev_err(&pdev->dev, "nci_allocate_device failed"); + rc = -ENOMEM; + goto free_exit; + } + + nci_set_parent_dev(drv->ndev, &pdev->dev); + nci_set_drvdata(drv->ndev, drv); + + rc = nci_register_device(drv->ndev); + if (rc < 0) { + nfc_dev_err(&pdev->dev, "nci_register_device failed %d", rc); + goto free_dev_exit; + } + + dev_set_drvdata(&pdev->dev, drv); + + goto exit; + +free_dev_exit: + nci_free_device(drv->ndev); + +free_exit: + kfree(drv); + +exit: + return rc; +} + +static int nfcwilink_remove(struct platform_device *pdev) +{ + struct nfcwilink *drv = dev_get_drvdata(&pdev->dev); + struct nci_dev *ndev; + + nfc_dev_dbg(&pdev->dev, "remove entry"); + + if (!drv) + return -EFAULT; + + ndev = drv->ndev; + + nci_unregister_device(ndev); + nci_free_device(ndev); + + kfree(drv); + + dev_set_drvdata(&pdev->dev, NULL); + + return 0; +} + +static struct platform_driver nfcwilink_driver = { + .probe = nfcwilink_probe, + .remove = nfcwilink_remove, + .driver = { + .name = "nfcwilink", + .owner = THIS_MODULE, + }, +}; + +/* ------- Module Init/Exit interfaces ------ */ +static int __init nfcwilink_init(void) +{ + printk(KERN_INFO "NFC Driver for TI WiLink"); + + return platform_driver_register(&nfcwilink_driver); +} + +static void __exit nfcwilink_exit(void) +{ + platform_driver_unregister(&nfcwilink_driver); +} + +module_init(nfcwilink_init); +module_exit(nfcwilink_exit); + +/* ------ Module Info ------ */ + +MODULE_AUTHOR("Ilan Elias "); +MODULE_DESCRIPTION("NFC Driver for TI Shared Transport"); +MODULE_LICENSE("GPL"); -- cgit v1.1