drivers/nfc/st21nfcb/st21nfcb.c

   1 /*
   2  * NCI based Driver for STMicroelectronics NFC Chip
   3  *
   4  * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/nfc.h>
  21 #include <net/nfc/nci.h>
  22 #include <net/nfc/nci_core.h>
  23
  24 #include "st21nfcb.h"
  25
  26 #define DRIVER_DESC "NCI NFC driver for ST21NFCB"
  27
  28 #define ST21NFCB_NCI1_X_PROPRIETARY_ISO15693 0x83
  29
  30 static int st21nfcb_nci_open(struct nci_dev *ndev)
  31 {
  32         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  33         int r;
  34
  35         if (test_and_set_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  36                 return 0;
  37
  38         r = ndlc_open(info->ndlc);
  39         if (r)
  40                 clear_bit(ST21NFCB_NCI_RUNNING, &info->flags);
  41
  42         return r;
  43 }
  44
  45 static int st21nfcb_nci_close(struct nci_dev *ndev)
  46 {
  47         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  48
  49         if (!test_and_clear_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  50                 return 0;
  51
  52         ndlc_close(info->ndlc);
  53
  54         return 0;
  55 }
  56
  57 static int st21nfcb_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
  58 {
  59         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
  60
  61         skb->dev = (void *)ndev;
  62
  63         if (!test_bit(ST21NFCB_NCI_RUNNING, &info->flags))
  64                 return -EBUSY;
  65
  66         return ndlc_send(info->ndlc, skb);
  67 }
  68
  69 static __u32 st21nfcb_nci_get_rfprotocol(struct nci_dev *ndev,
  70                                          __u8 rf_protocol)
  71 {
  72         return rf_protocol == ST21NFCB_NCI1_X_PROPRIETARY_ISO15693 ?
  73                 NFC_PROTO_ISO15693_MASK : 0;
  74 }
  75
  76 static struct nci_ops st21nfcb_nci_ops = {
  77         .open = st21nfcb_nci_open,
  78         .close = st21nfcb_nci_close,
  79         .send = st21nfcb_nci_send,
  80         .get_rfprotocol = st21nfcb_nci_get_rfprotocol,
  81 };
  82
  83 int st21nfcb_nci_probe(struct llt_ndlc *ndlc, int phy_headroom,
  84                        int phy_tailroom)
  85 {
  86         struct st21nfcb_nci_info *info;
  87         int r;
  88         u32 protocols;
  89
  90         info = devm_kzalloc(ndlc->dev,
  91                         sizeof(struct st21nfcb_nci_info), GFP_KERNEL);
  92         if (!info)
  93                 return -ENOMEM;
  94
  95         protocols = NFC_PROTO_JEWEL_MASK
  96                 | NFC_PROTO_MIFARE_MASK
  97                 | NFC_PROTO_FELICA_MASK
  98                 | NFC_PROTO_ISO14443_MASK
  99                 | NFC_PROTO_ISO14443_B_MASK
 100                 | NFC_PROTO_ISO15693_MASK
 101                 | NFC_PROTO_NFC_DEP_MASK;
 102
 103         ndlc->ndev = nci_allocate_device(&st21nfcb_nci_ops, protocols,
 104                                         phy_headroom, phy_tailroom);
 105         if (!ndlc->ndev) {
 106                 pr_err("Cannot allocate nfc ndev\n");
 107                 return -ENOMEM;
 108         }
 109         info->ndlc = ndlc;
 110
 111         nci_set_drvdata(ndlc->ndev, info);
 112
 113         r = nci_register_device(ndlc->ndev);
 114         if (r) {
 115                 pr_err("Cannot register nfc device to nci core\n");
 116                 nci_free_device(ndlc->ndev);
 117         }
 118
 119         return r;
 120 }
 121 EXPORT_SYMBOL_GPL(st21nfcb_nci_probe);
 122
 123 void st21nfcb_nci_remove(struct nci_dev *ndev)
 124 {
 125         struct st21nfcb_nci_info *info = nci_get_drvdata(ndev);
 126
 127         nci_unregister_device(ndev);
 128         nci_free_device(ndev);
 129         kfree(info);
 130 }
 131 EXPORT_SYMBOL_GPL(st21nfcb_nci_remove);
 132
 133 MODULE_LICENSE("GPL");
 134 MODULE_DESCRIPTION(DRIVER_DESC);