Daniel Mentz | 94787a1 | 2013-05-29 21:12:04 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Texas Instrument's NFC Driver For Shared Transport. |
| 3 | * |
| 4 | * NFC Driver acts as interface between NCI core and |
| 5 | * TI Shared Transport Layer. |
| 6 | * |
| 7 | * Copyright (C) 2011 Texas Instruments, Inc. |
| 8 | * |
| 9 | * Written by Ilan Elias <ilane@ti.com> |
| 10 | * |
| 11 | * Acknowledgements: |
| 12 | * This file is based on btwilink.c, which was written |
| 13 | * by Raja Mani and Pavan Savoy. |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or modify |
| 16 | * it under the terms of the GNU General Public License version 2 as |
| 17 | * published by the Free Software Foundation. |
| 18 | * |
| 19 | * This program is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with this program; if not, write to the Free Software |
| 26 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 27 | * |
| 28 | */ |
| 29 | #include <linux/platform_device.h> |
| 30 | #include <linux/module.h> |
| 31 | #include <linux/nfc.h> |
| 32 | #include <net/nfc/nci.h> |
| 33 | #include <net/nfc/nci_core.h> |
| 34 | #include <linux/ti_wilink_st.h> |
| 35 | |
| 36 | #define NFCWILINK_CHNL 12 |
| 37 | #define NFCWILINK_OPCODE 7 |
| 38 | #define NFCWILINK_MAX_FRAME_SIZE 300 |
| 39 | #define NFCWILINK_HDR_LEN 4 |
| 40 | #define NFCWILINK_OFFSET_LEN_IN_HDR 1 |
| 41 | #define NFCWILINK_LEN_SIZE 2 |
| 42 | #define NFCWILINK_REGISTER_TIMEOUT 8000 /* 8 sec */ |
| 43 | |
| 44 | struct nfcwilink_hdr { |
| 45 | u8 chnl; |
| 46 | u8 opcode; |
| 47 | u16 len; |
| 48 | } __packed; |
| 49 | |
| 50 | struct nfcwilink { |
| 51 | struct platform_device *pdev; |
| 52 | struct nci_dev *ndev; |
| 53 | unsigned long flags; |
| 54 | |
| 55 | char st_register_cb_status; |
| 56 | long (*st_write) (struct sk_buff *); |
| 57 | struct completion st_register_completed; |
| 58 | }; |
| 59 | |
| 60 | /* NFCWILINK driver flags */ |
| 61 | enum { |
| 62 | NFCWILINK_RUNNING, |
| 63 | }; |
| 64 | |
| 65 | /* Called by ST when registration is complete */ |
| 66 | static void nfcwilink_register_complete(void *priv_data, char data) |
| 67 | { |
| 68 | struct nfcwilink *drv = priv_data; |
| 69 | |
| 70 | nfc_dev_dbg(&drv->pdev->dev, "register_complete entry"); |
| 71 | |
| 72 | /* store ST registration status */ |
| 73 | drv->st_register_cb_status = data; |
| 74 | |
| 75 | /* complete the wait in nfc_st_open() */ |
| 76 | complete(&drv->st_register_completed); |
| 77 | } |
| 78 | |
| 79 | /* Called by ST when receive data is available */ |
| 80 | static long nfcwilink_receive(void *priv_data, struct sk_buff *skb) |
| 81 | { |
| 82 | struct nfcwilink *drv = priv_data; |
| 83 | int rc; |
| 84 | |
| 85 | nfc_dev_dbg(&drv->pdev->dev, "receive entry, len %d", skb->len); |
| 86 | |
| 87 | if (!skb) |
| 88 | return -EFAULT; |
| 89 | |
| 90 | if (!drv) { |
| 91 | kfree_skb(skb); |
| 92 | return -EFAULT; |
| 93 | } |
| 94 | |
| 95 | /* strip the ST header |
| 96 | (apart for the chnl byte, which is not received in the hdr) */ |
| 97 | skb_pull(skb, (NFCWILINK_HDR_LEN-1)); |
| 98 | |
| 99 | skb->dev = (void *) drv->ndev; |
| 100 | |
| 101 | /* Forward skb to NCI core layer */ |
| 102 | rc = nci_recv_frame(skb); |
| 103 | if (rc < 0) { |
| 104 | nfc_dev_err(&drv->pdev->dev, "nci_recv_frame failed %d", rc); |
| 105 | return rc; |
| 106 | } |
| 107 | |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | /* protocol structure registered with ST */ |
| 112 | static struct st_proto_s nfcwilink_proto = { |
| 113 | .chnl_id = NFCWILINK_CHNL, |
| 114 | .max_frame_size = NFCWILINK_MAX_FRAME_SIZE, |
| 115 | .hdr_len = (NFCWILINK_HDR_LEN-1), /* not including chnl byte */ |
| 116 | .offset_len_in_hdr = NFCWILINK_OFFSET_LEN_IN_HDR, |
| 117 | .len_size = NFCWILINK_LEN_SIZE, |
| 118 | .reserve = 0, |
| 119 | .recv = nfcwilink_receive, |
| 120 | .reg_complete_cb = nfcwilink_register_complete, |
| 121 | .write = NULL, |
| 122 | }; |
| 123 | |
| 124 | static int nfcwilink_open(struct nci_dev *ndev) |
| 125 | { |
| 126 | struct nfcwilink *drv = nci_get_drvdata(ndev); |
| 127 | unsigned long comp_ret; |
| 128 | int rc; |
| 129 | |
| 130 | nfc_dev_dbg(&drv->pdev->dev, "open entry"); |
| 131 | |
| 132 | if (test_and_set_bit(NFCWILINK_RUNNING, &drv->flags)) { |
| 133 | rc = -EBUSY; |
| 134 | goto exit; |
| 135 | } |
| 136 | |
| 137 | nfcwilink_proto.priv_data = drv; |
| 138 | |
| 139 | init_completion(&drv->st_register_completed); |
| 140 | drv->st_register_cb_status = -EINPROGRESS; |
| 141 | |
| 142 | rc = st_register(&nfcwilink_proto); |
| 143 | if (rc < 0) { |
| 144 | if (rc == -EINPROGRESS) { |
| 145 | comp_ret = wait_for_completion_timeout( |
| 146 | &drv->st_register_completed, |
| 147 | msecs_to_jiffies(NFCWILINK_REGISTER_TIMEOUT)); |
| 148 | |
| 149 | nfc_dev_dbg(&drv->pdev->dev, |
| 150 | "wait_for_completion_timeout returned %ld", |
| 151 | comp_ret); |
| 152 | |
| 153 | if (comp_ret == 0) { |
| 154 | /* timeout */ |
| 155 | rc = -ETIMEDOUT; |
| 156 | goto clear_exit; |
| 157 | } else if (drv->st_register_cb_status != 0) { |
| 158 | rc = drv->st_register_cb_status; |
| 159 | nfc_dev_err(&drv->pdev->dev, |
| 160 | "st_register_cb failed %d", rc); |
| 161 | goto clear_exit; |
| 162 | } |
| 163 | } else { |
| 164 | nfc_dev_err(&drv->pdev->dev, |
| 165 | "st_register failed %d", rc); |
| 166 | goto clear_exit; |
| 167 | } |
| 168 | } |
| 169 | |
| 170 | /* st_register MUST fill the write callback */ |
| 171 | BUG_ON(nfcwilink_proto.write == NULL); |
| 172 | drv->st_write = nfcwilink_proto.write; |
| 173 | |
| 174 | goto exit; |
| 175 | |
| 176 | clear_exit: |
| 177 | clear_bit(NFCWILINK_RUNNING, &drv->flags); |
| 178 | |
| 179 | exit: |
| 180 | return rc; |
| 181 | } |
| 182 | |
| 183 | static int nfcwilink_close(struct nci_dev *ndev) |
| 184 | { |
| 185 | struct nfcwilink *drv = nci_get_drvdata(ndev); |
| 186 | int rc; |
| 187 | |
| 188 | nfc_dev_dbg(&drv->pdev->dev, "close entry"); |
| 189 | |
| 190 | if (!test_and_clear_bit(NFCWILINK_RUNNING, &drv->flags)) |
| 191 | return 0; |
| 192 | |
| 193 | rc = st_unregister(&nfcwilink_proto); |
| 194 | if (rc) |
| 195 | nfc_dev_err(&drv->pdev->dev, "st_unregister failed %d", rc); |
| 196 | |
| 197 | drv->st_write = NULL; |
| 198 | |
| 199 | return rc; |
| 200 | } |
| 201 | |
| 202 | static int nfcwilink_send(struct sk_buff *skb) |
| 203 | { |
| 204 | struct nci_dev *ndev = (struct nci_dev *)skb->dev; |
| 205 | struct nfcwilink *drv = nci_get_drvdata(ndev); |
| 206 | struct nfcwilink_hdr hdr = {NFCWILINK_CHNL, NFCWILINK_OPCODE, 0x0000}; |
| 207 | long len; |
| 208 | |
| 209 | nfc_dev_dbg(&drv->pdev->dev, "send entry, len %d", skb->len); |
| 210 | |
| 211 | if (!test_bit(NFCWILINK_RUNNING, &drv->flags)) |
| 212 | return -EBUSY; |
| 213 | |
| 214 | /* add the ST hdr to the start of the buffer */ |
| 215 | hdr.len = skb->len; |
| 216 | memcpy(skb_push(skb, NFCWILINK_HDR_LEN), &hdr, NFCWILINK_HDR_LEN); |
| 217 | |
| 218 | /* Insert skb to shared transport layer's transmit queue. |
| 219 | * Freeing skb memory is taken care in shared transport layer, |
| 220 | * so don't free skb memory here. |
| 221 | */ |
| 222 | len = drv->st_write(skb); |
| 223 | if (len < 0) { |
| 224 | kfree_skb(skb); |
| 225 | nfc_dev_err(&drv->pdev->dev, "st_write failed %ld", len); |
| 226 | return -EFAULT; |
| 227 | } |
| 228 | |
| 229 | return 0; |
| 230 | } |
| 231 | |
| 232 | static struct nci_ops nfcwilink_ops = { |
| 233 | .open = nfcwilink_open, |
| 234 | .close = nfcwilink_close, |
| 235 | .send = nfcwilink_send, |
| 236 | }; |
| 237 | |
| 238 | static int nfcwilink_probe(struct platform_device *pdev) |
| 239 | { |
| 240 | static struct nfcwilink *drv; |
| 241 | int rc; |
| 242 | u32 protocols; |
| 243 | |
| 244 | nfc_dev_dbg(&pdev->dev, "probe entry"); |
| 245 | |
| 246 | drv = kzalloc(sizeof(struct nfcwilink), GFP_KERNEL); |
| 247 | if (!drv) { |
| 248 | rc = -ENOMEM; |
| 249 | goto exit; |
| 250 | } |
| 251 | |
| 252 | drv->pdev = pdev; |
| 253 | |
| 254 | protocols = NFC_PROTO_JEWEL_MASK |
| 255 | | NFC_PROTO_MIFARE_MASK | NFC_PROTO_FELICA_MASK |
| 256 | | NFC_PROTO_ISO14443_MASK |
| 257 | | NFC_PROTO_NFC_DEP_MASK; |
| 258 | |
| 259 | drv->ndev = nci_allocate_device(&nfcwilink_ops, |
| 260 | protocols, |
| 261 | NFCWILINK_HDR_LEN, |
| 262 | 0); |
| 263 | if (!drv->ndev) { |
| 264 | nfc_dev_err(&pdev->dev, "nci_allocate_device failed"); |
| 265 | rc = -ENOMEM; |
| 266 | goto free_exit; |
| 267 | } |
| 268 | |
| 269 | nci_set_parent_dev(drv->ndev, &pdev->dev); |
| 270 | nci_set_drvdata(drv->ndev, drv); |
| 271 | |
| 272 | rc = nci_register_device(drv->ndev); |
| 273 | if (rc < 0) { |
| 274 | nfc_dev_err(&pdev->dev, "nci_register_device failed %d", rc); |
| 275 | goto free_dev_exit; |
| 276 | } |
| 277 | |
| 278 | dev_set_drvdata(&pdev->dev, drv); |
| 279 | |
| 280 | goto exit; |
| 281 | |
| 282 | free_dev_exit: |
| 283 | nci_free_device(drv->ndev); |
| 284 | |
| 285 | free_exit: |
| 286 | kfree(drv); |
| 287 | |
| 288 | exit: |
| 289 | return rc; |
| 290 | } |
| 291 | |
| 292 | static int nfcwilink_remove(struct platform_device *pdev) |
| 293 | { |
| 294 | struct nfcwilink *drv = dev_get_drvdata(&pdev->dev); |
| 295 | struct nci_dev *ndev; |
| 296 | |
| 297 | nfc_dev_dbg(&pdev->dev, "remove entry"); |
| 298 | |
| 299 | if (!drv) |
| 300 | return -EFAULT; |
| 301 | |
| 302 | ndev = drv->ndev; |
| 303 | |
| 304 | nci_unregister_device(ndev); |
| 305 | nci_free_device(ndev); |
| 306 | |
| 307 | kfree(drv); |
| 308 | |
| 309 | dev_set_drvdata(&pdev->dev, NULL); |
| 310 | |
| 311 | return 0; |
| 312 | } |
| 313 | |
| 314 | static struct platform_driver nfcwilink_driver = { |
| 315 | .probe = nfcwilink_probe, |
| 316 | .remove = nfcwilink_remove, |
| 317 | .driver = { |
| 318 | .name = "nfcwilink", |
| 319 | .owner = THIS_MODULE, |
| 320 | }, |
| 321 | }; |
| 322 | |
| 323 | /* ------- Module Init/Exit interfaces ------ */ |
| 324 | static int __init nfcwilink_init(void) |
| 325 | { |
| 326 | printk(KERN_INFO "NFC Driver for TI WiLink"); |
| 327 | |
| 328 | return platform_driver_register(&nfcwilink_driver); |
| 329 | } |
| 330 | |
| 331 | static void __exit nfcwilink_exit(void) |
| 332 | { |
| 333 | platform_driver_unregister(&nfcwilink_driver); |
| 334 | } |
| 335 | |
| 336 | module_init(nfcwilink_init); |
| 337 | module_exit(nfcwilink_exit); |
| 338 | |
| 339 | /* ------ Module Info ------ */ |
| 340 | |
| 341 | MODULE_AUTHOR("Ilan Elias <ilane@ti.com>"); |
| 342 | MODULE_DESCRIPTION("NFC Driver for TI Shared Transport"); |
| 343 | MODULE_LICENSE("GPL"); |