1 /* 2 * I2C Link Layer for ST21NFCA HCI based Driver 3 * Copyright (C) 2014 STMicroelectronics SAS. All rights reserved. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 19 20 #include <linux/crc-ccitt.h> 21 #include <linux/module.h> 22 #include <linux/i2c.h> 23 #include <linux/gpio.h> 24 #include <linux/of_irq.h> 25 #include <linux/of_gpio.h> 26 #include <linux/miscdevice.h> 27 #include <linux/interrupt.h> 28 #include <linux/delay.h> 29 #include <linux/nfc.h> 30 #include <linux/firmware.h> 31 #include <linux/unaligned/access_ok.h> 32 #include <linux/platform_data/st21nfca.h> 33 34 #include <net/nfc/hci.h> 35 #include <net/nfc/llc.h> 36 #include <net/nfc/nfc.h> 37 38 #include "st21nfca.h" 39 40 /* 41 * Every frame starts with ST21NFCA_SOF_EOF and ends with ST21NFCA_SOF_EOF. 42 * Because ST21NFCA_SOF_EOF is a possible data value, there is a mecanism 43 * called byte stuffing has been introduced. 44 * 45 * if byte == ST21NFCA_SOF_EOF or ST21NFCA_ESCAPE_BYTE_STUFFING 46 * - insert ST21NFCA_ESCAPE_BYTE_STUFFING (escape byte) 47 * - xor byte with ST21NFCA_BYTE_STUFFING_MASK 48 */ 49 #define ST21NFCA_SOF_EOF 0x7e 50 #define ST21NFCA_BYTE_STUFFING_MASK 0x20 51 #define ST21NFCA_ESCAPE_BYTE_STUFFING 0x7d 52 53 /* SOF + 00 */ 54 #define ST21NFCA_FRAME_HEADROOM 2 55 56 /* 2 bytes crc + EOF */ 57 #define ST21NFCA_FRAME_TAILROOM 3 58 #define IS_START_OF_FRAME(buf) (buf[0] == ST21NFCA_SOF_EOF && \ 59 buf[1] == 0) 60 61 #define ST21NFCA_HCI_I2C_DRIVER_NAME "st21nfca_hci_i2c" 62 63 static struct i2c_device_id st21nfca_hci_i2c_id_table[] = { 64 {ST21NFCA_HCI_DRIVER_NAME, 0}, 65 {} 66 }; 67 68 MODULE_DEVICE_TABLE(i2c, st21nfca_hci_i2c_id_table); 69 70 struct st21nfca_i2c_phy { 71 struct i2c_client *i2c_dev; 72 struct nfc_hci_dev *hdev; 73 74 unsigned int gpio_ena; 75 unsigned int gpio_irq; 76 unsigned int irq_polarity; 77 78 struct sk_buff *pending_skb; 79 int current_read_len; 80 /* 81 * crc might have fail because i2c macro 82 * is disable due to other interface activity 83 */ 84 int crc_trials; 85 86 int powered; 87 int run_mode; 88 89 /* 90 * < 0 if hardware error occured (e.g. i2c err) 91 * and prevents normal operation. 92 */ 93 int hard_fault; 94 struct mutex phy_lock; 95 }; 96 static u8 len_seq[] = { 16, 24, 12, 29 }; 97 static u16 wait_tab[] = { 2, 3, 5, 15, 20, 40}; 98 99 #define I2C_DUMP_SKB(info, skb) \ 100 do { \ 101 pr_debug("%s:\n", info); \ 102 print_hex_dump(KERN_DEBUG, "i2c: ", DUMP_PREFIX_OFFSET, \ 103 16, 1, (skb)->data, (skb)->len, 0); \ 104 } while (0) 105 106 /* 107 * In order to get the CLF in a known state we generate an internal reboot 108 * using a proprietary command. 109 * Once the reboot is completed, we expect to receive a ST21NFCA_SOF_EOF 110 * fill buffer. 111 */ 112 static int st21nfca_hci_platform_init(struct st21nfca_i2c_phy *phy) 113 { 114 u16 wait_reboot[] = { 50, 300, 1000 }; 115 char reboot_cmd[] = { 0x7E, 0x66, 0x48, 0xF6, 0x7E }; 116 u8 tmp[ST21NFCA_HCI_LLC_MAX_SIZE]; 117 int i, r = -1; 118 119 for (i = 0; i < ARRAY_SIZE(wait_reboot) && r < 0; i++) { 120 r = i2c_master_send(phy->i2c_dev, reboot_cmd, 121 sizeof(reboot_cmd)); 122 if (r < 0) 123 msleep(wait_reboot[i]); 124 } 125 if (r < 0) 126 return r; 127 128 /* CLF is spending about 20ms to do an internal reboot */ 129 msleep(20); 130 r = -1; 131 for (i = 0; i < ARRAY_SIZE(wait_reboot) && r < 0; i++) { 132 r = i2c_master_recv(phy->i2c_dev, tmp, 133 ST21NFCA_HCI_LLC_MAX_SIZE); 134 if (r < 0) 135 msleep(wait_reboot[i]); 136 } 137 if (r < 0) 138 return r; 139 140 for (i = 0; i < ST21NFCA_HCI_LLC_MAX_SIZE && 141 tmp[i] == ST21NFCA_SOF_EOF; i++) 142 ; 143 144 if (r != ST21NFCA_HCI_LLC_MAX_SIZE) 145 return -ENODEV; 146 147 usleep_range(1000, 1500); 148 return 0; 149 } 150 151 static int st21nfca_hci_i2c_enable(void *phy_id) 152 { 153 struct st21nfca_i2c_phy *phy = phy_id; 154 155 gpio_set_value(phy->gpio_ena, 1); 156 phy->powered = 1; 157 phy->run_mode = ST21NFCA_HCI_MODE; 158 159 usleep_range(10000, 15000); 160 161 return 0; 162 } 163 164 static void st21nfca_hci_i2c_disable(void *phy_id) 165 { 166 struct st21nfca_i2c_phy *phy = phy_id; 167 168 pr_info("\n"); 169 gpio_set_value(phy->gpio_ena, 0); 170 171 phy->powered = 0; 172 } 173 174 static void st21nfca_hci_add_len_crc(struct sk_buff *skb) 175 { 176 u16 crc; 177 u8 tmp; 178 179 *skb_push(skb, 1) = 0; 180 181 crc = crc_ccitt(0xffff, skb->data, skb->len); 182 crc = ~crc; 183 184 tmp = crc & 0x00ff; 185 *skb_put(skb, 1) = tmp; 186 187 tmp = (crc >> 8) & 0x00ff; 188 *skb_put(skb, 1) = tmp; 189 } 190 191 static void st21nfca_hci_remove_len_crc(struct sk_buff *skb) 192 { 193 skb_pull(skb, ST21NFCA_FRAME_HEADROOM); 194 skb_trim(skb, skb->len - ST21NFCA_FRAME_TAILROOM); 195 } 196 197 /* 198 * Writing a frame must not return the number of written bytes. 199 * It must return either zero for success, or <0 for error. 200 * In addition, it must not alter the skb 201 */ 202 static int st21nfca_hci_i2c_write(void *phy_id, struct sk_buff *skb) 203 { 204 int r = -1, i, j; 205 struct st21nfca_i2c_phy *phy = phy_id; 206 struct i2c_client *client = phy->i2c_dev; 207 u8 tmp[ST21NFCA_HCI_LLC_MAX_SIZE * 2]; 208 209 I2C_DUMP_SKB("st21nfca_hci_i2c_write", skb); 210 211 212 if (phy->hard_fault != 0) 213 return phy->hard_fault; 214 215 /* 216 * Compute CRC before byte stuffing computation on frame 217 * Note st21nfca_hci_add_len_crc is doing a byte stuffing 218 * on its own value 219 */ 220 st21nfca_hci_add_len_crc(skb); 221 222 /* add ST21NFCA_SOF_EOF on tail */ 223 *skb_put(skb, 1) = ST21NFCA_SOF_EOF; 224 /* add ST21NFCA_SOF_EOF on head */ 225 *skb_push(skb, 1) = ST21NFCA_SOF_EOF; 226 227 /* 228 * Compute byte stuffing 229 * if byte == ST21NFCA_SOF_EOF or ST21NFCA_ESCAPE_BYTE_STUFFING 230 * insert ST21NFCA_ESCAPE_BYTE_STUFFING (escape byte) 231 * xor byte with ST21NFCA_BYTE_STUFFING_MASK 232 */ 233 tmp[0] = skb->data[0]; 234 for (i = 1, j = 1; i < skb->len - 1; i++, j++) { 235 if (skb->data[i] == ST21NFCA_SOF_EOF 236 || skb->data[i] == ST21NFCA_ESCAPE_BYTE_STUFFING) { 237 tmp[j] = ST21NFCA_ESCAPE_BYTE_STUFFING; 238 j++; 239 tmp[j] = skb->data[i] ^ ST21NFCA_BYTE_STUFFING_MASK; 240 } else { 241 tmp[j] = skb->data[i]; 242 } 243 } 244 tmp[j] = skb->data[i]; 245 j++; 246 247 /* 248 * Manage sleep mode 249 * Try 3 times to send data with delay between each 250 */ 251 mutex_lock(&phy->phy_lock); 252 for (i = 0; i < ARRAY_SIZE(wait_tab) && r < 0; i++) { 253 r = i2c_master_send(client, tmp, j); 254 if (r < 0) 255 msleep(wait_tab[i]); 256 } 257 mutex_unlock(&phy->phy_lock); 258 259 if (r >= 0) { 260 if (r != j) 261 r = -EREMOTEIO; 262 else 263 r = 0; 264 } 265 266 st21nfca_hci_remove_len_crc(skb); 267 268 return r; 269 } 270 271 static int get_frame_size(u8 *buf, int buflen) 272 { 273 int len = 0; 274 if (buf[len + 1] == ST21NFCA_SOF_EOF) 275 return 0; 276 277 for (len = 1; len < buflen && buf[len] != ST21NFCA_SOF_EOF; len++) 278 ; 279 280 return len; 281 } 282 283 static int check_crc(u8 *buf, int buflen) 284 { 285 u16 crc; 286 287 crc = crc_ccitt(0xffff, buf, buflen - 2); 288 crc = ~crc; 289 290 if (buf[buflen - 2] != (crc & 0xff) || buf[buflen - 1] != (crc >> 8)) { 291 pr_err(ST21NFCA_HCI_DRIVER_NAME 292 ": CRC error 0x%x != 0x%x 0x%x\n", crc, buf[buflen - 1], 293 buf[buflen - 2]); 294 295 pr_info(DRIVER_DESC ": %s : BAD CRC\n", __func__); 296 print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, 297 16, 2, buf, buflen, false); 298 return -EPERM; 299 } 300 return 0; 301 } 302 303 /* 304 * Prepare received data for upper layer. 305 * Received data include byte stuffing, crc and sof/eof 306 * which is not usable by hci part. 307 * returns: 308 * frame size without sof/eof, header and byte stuffing 309 * -EBADMSG : frame was incorrect and discarded 310 */ 311 static int st21nfca_hci_i2c_repack(struct sk_buff *skb) 312 { 313 int i, j, r, size; 314 if (skb->len < 1 || (skb->len > 1 && skb->data[1] != 0)) 315 return -EBADMSG; 316 317 size = get_frame_size(skb->data, skb->len); 318 if (size > 0) { 319 skb_trim(skb, size); 320 /* remove ST21NFCA byte stuffing for upper layer */ 321 for (i = 1, j = 0; i < skb->len; i++) { 322 if (skb->data[i + j] == 323 (u8) ST21NFCA_ESCAPE_BYTE_STUFFING) { 324 skb->data[i] = skb->data[i + j + 1] 325 | ST21NFCA_BYTE_STUFFING_MASK; 326 i++; 327 j++; 328 } 329 skb->data[i] = skb->data[i + j]; 330 } 331 /* remove byte stuffing useless byte */ 332 skb_trim(skb, i - j); 333 /* remove ST21NFCA_SOF_EOF from head */ 334 skb_pull(skb, 1); 335 336 r = check_crc(skb->data, skb->len); 337 if (r != 0) { 338 i = 0; 339 return -EBADMSG; 340 } 341 342 /* remove headbyte */ 343 skb_pull(skb, 1); 344 /* remove crc. Byte Stuffing is already removed here */ 345 skb_trim(skb, skb->len - 2); 346 return skb->len; 347 } 348 return 0; 349 } 350 351 /* 352 * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees 353 * that i2c bus will be flushed and that next read will start on a new frame. 354 * returned skb contains only LLC header and payload. 355 * returns: 356 * frame size : if received frame is complete (find ST21NFCA_SOF_EOF at 357 * end of read) 358 * -EAGAIN : if received frame is incomplete (not find ST21NFCA_SOF_EOF 359 * at end of read) 360 * -EREMOTEIO : i2c read error (fatal) 361 * -EBADMSG : frame was incorrect and discarded 362 * (value returned from st21nfca_hci_i2c_repack) 363 * -EIO : if no ST21NFCA_SOF_EOF is found after reaching 364 * the read length end sequence 365 */ 366 static int st21nfca_hci_i2c_read(struct st21nfca_i2c_phy *phy, 367 struct sk_buff *skb) 368 { 369 int r, i; 370 u8 len; 371 u8 buf[ST21NFCA_HCI_LLC_MAX_PAYLOAD]; 372 struct i2c_client *client = phy->i2c_dev; 373 374 if (phy->current_read_len < ARRAY_SIZE(len_seq)) { 375 len = len_seq[phy->current_read_len]; 376 377 /* 378 * Add retry mecanism 379 * Operation on I2C interface may fail in case of operation on 380 * RF or SWP interface 381 */ 382 r = 0; 383 mutex_lock(&phy->phy_lock); 384 for (i = 0; i < ARRAY_SIZE(wait_tab) && r <= 0; i++) { 385 r = i2c_master_recv(client, buf, len); 386 if (r < 0) 387 msleep(wait_tab[i]); 388 } 389 mutex_unlock(&phy->phy_lock); 390 391 if (r != len) { 392 phy->current_read_len = 0; 393 return -EREMOTEIO; 394 } 395 396 /* 397 * The first read sequence does not start with SOF. 398 * Data is corrupeted so we drop it. 399 */ 400 if (!phy->current_read_len && !IS_START_OF_FRAME(buf)) { 401 skb_trim(skb, 0); 402 phy->current_read_len = 0; 403 return -EIO; 404 } else if (phy->current_read_len && IS_START_OF_FRAME(buf)) { 405 /* 406 * Previous frame transmission was interrupted and 407 * the frame got repeated. 408 * Received frame start with ST21NFCA_SOF_EOF + 00. 409 */ 410 skb_trim(skb, 0); 411 phy->current_read_len = 0; 412 } 413 414 memcpy(skb_put(skb, len), buf, len); 415 416 if (skb->data[skb->len - 1] == ST21NFCA_SOF_EOF) { 417 phy->current_read_len = 0; 418 return st21nfca_hci_i2c_repack(skb); 419 } 420 phy->current_read_len++; 421 return -EAGAIN; 422 } 423 return -EIO; 424 } 425 426 /* 427 * Reads an shdlc frame from the chip. This is not as straightforward as it 428 * seems. The frame format is data-crc, and corruption can occur anywhere 429 * while transiting on i2c bus, such that we could read an invalid data. 430 * The tricky case is when we read a corrupted data or crc. We must detect 431 * this here in order to determine that data can be transmitted to the hci 432 * core. This is the reason why we check the crc here. 433 * The CLF will repeat a frame until we send a RR on that frame. 434 * 435 * On ST21NFCA, IRQ goes in idle when read starts. As no size information are 436 * available in the incoming data, other IRQ might come. Every IRQ will trigger 437 * a read sequence with different length and will fill the current frame. 438 * The reception is complete once we reach a ST21NFCA_SOF_EOF. 439 */ 440 static irqreturn_t st21nfca_hci_irq_thread_fn(int irq, void *phy_id) 441 { 442 struct st21nfca_i2c_phy *phy = phy_id; 443 struct i2c_client *client; 444 445 int r; 446 447 if (!phy || irq != phy->i2c_dev->irq) { 448 WARN_ON_ONCE(1); 449 return IRQ_NONE; 450 } 451 452 client = phy->i2c_dev; 453 dev_dbg(&client->dev, "IRQ\n"); 454 455 if (phy->hard_fault != 0) 456 return IRQ_HANDLED; 457 458 r = st21nfca_hci_i2c_read(phy, phy->pending_skb); 459 if (r == -EREMOTEIO) { 460 phy->hard_fault = r; 461 462 nfc_hci_recv_frame(phy->hdev, NULL); 463 464 return IRQ_HANDLED; 465 } else if (r == -EAGAIN || r == -EIO) { 466 return IRQ_HANDLED; 467 } else if (r == -EBADMSG && phy->crc_trials < ARRAY_SIZE(wait_tab)) { 468 /* 469 * With ST21NFCA, only one interface (I2C, RF or SWP) 470 * may be active at a time. 471 * Having incorrect crc is usually due to i2c macrocell 472 * deactivation in the middle of a transmission. 473 * It may generate corrupted data on i2c. 474 * We give sometime to get i2c back. 475 * The complete frame will be repeated. 476 */ 477 msleep(wait_tab[phy->crc_trials]); 478 phy->crc_trials++; 479 phy->current_read_len = 0; 480 kfree_skb(phy->pending_skb); 481 } else if (r > 0) { 482 /* 483 * We succeeded to read data from the CLF and 484 * data is valid. 485 * Reset counter. 486 */ 487 nfc_hci_recv_frame(phy->hdev, phy->pending_skb); 488 phy->crc_trials = 0; 489 } else { 490 kfree_skb(phy->pending_skb); 491 } 492 493 phy->pending_skb = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE * 2, GFP_KERNEL); 494 if (phy->pending_skb == NULL) { 495 phy->hard_fault = -ENOMEM; 496 nfc_hci_recv_frame(phy->hdev, NULL); 497 } 498 499 return IRQ_HANDLED; 500 } 501 502 static struct nfc_phy_ops i2c_phy_ops = { 503 .write = st21nfca_hci_i2c_write, 504 .enable = st21nfca_hci_i2c_enable, 505 .disable = st21nfca_hci_i2c_disable, 506 }; 507 508 #ifdef CONFIG_OF 509 static int st21nfca_hci_i2c_of_request_resources(struct i2c_client *client) 510 { 511 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 512 struct device_node *pp; 513 int gpio; 514 int r; 515 516 pp = client->dev.of_node; 517 if (!pp) 518 return -ENODEV; 519 520 /* Get GPIO from device tree */ 521 gpio = of_get_named_gpio(pp, "enable-gpios", 0); 522 if (gpio < 0) { 523 nfc_err(&client->dev, "Failed to retrieve enable-gpios from device tree\n"); 524 return gpio; 525 } 526 527 /* GPIO request and configuration */ 528 r = devm_gpio_request(&client->dev, gpio, "clf_enable"); 529 if (r) { 530 nfc_err(&client->dev, "Failed to request enable pin\n"); 531 return -ENODEV; 532 } 533 534 r = gpio_direction_output(gpio, 1); 535 if (r) { 536 nfc_err(&client->dev, "Failed to set enable pin direction as output\n"); 537 return -ENODEV; 538 } 539 phy->gpio_ena = gpio; 540 541 /* IRQ */ 542 r = irq_of_parse_and_map(pp, 0); 543 if (r < 0) { 544 nfc_err(&client->dev, 545 "Unable to get irq, error: %d\n", r); 546 return r; 547 } 548 549 phy->irq_polarity = irq_get_trigger_type(r); 550 client->irq = r; 551 552 return 0; 553 } 554 #else 555 static int st21nfca_hci_i2c_of_request_resources(struct i2c_client *client) 556 { 557 return -ENODEV; 558 } 559 #endif 560 561 static int st21nfca_hci_i2c_request_resources(struct i2c_client *client) 562 { 563 struct st21nfca_nfc_platform_data *pdata; 564 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 565 int r; 566 int irq; 567 568 pdata = client->dev.platform_data; 569 if (pdata == NULL) { 570 nfc_err(&client->dev, "No platform data\n"); 571 return -EINVAL; 572 } 573 574 /* store for later use */ 575 phy->gpio_irq = pdata->gpio_irq; 576 phy->gpio_ena = pdata->gpio_ena; 577 phy->irq_polarity = pdata->irq_polarity; 578 579 r = devm_gpio_request(&client->dev, phy->gpio_irq, "wake_up"); 580 if (r) { 581 pr_err("%s : gpio_request failed\n", __FILE__); 582 return -ENODEV; 583 } 584 585 r = gpio_direction_input(phy->gpio_irq); 586 if (r) { 587 pr_err("%s : gpio_direction_input failed\n", __FILE__); 588 return -ENODEV; 589 } 590 591 if (phy->gpio_ena > 0) { 592 r = devm_gpio_request(&client->dev, 593 phy->gpio_ena, "clf_enable"); 594 if (r) { 595 pr_err("%s : ena gpio_request failed\n", __FILE__); 596 return -ENODEV; 597 } 598 r = gpio_direction_output(phy->gpio_ena, 1); 599 600 if (r) { 601 pr_err("%s : ena gpio_direction_output failed\n", 602 __FILE__); 603 return -ENODEV; 604 } 605 } 606 607 /* IRQ */ 608 irq = gpio_to_irq(phy->gpio_irq); 609 if (irq < 0) { 610 nfc_err(&client->dev, 611 "Unable to get irq number for GPIO %d error %d\n", 612 phy->gpio_irq, r); 613 return -ENODEV; 614 } 615 client->irq = irq; 616 617 return 0; 618 } 619 620 static int st21nfca_hci_i2c_probe(struct i2c_client *client, 621 const struct i2c_device_id *id) 622 { 623 struct st21nfca_i2c_phy *phy; 624 struct st21nfca_nfc_platform_data *pdata; 625 int r; 626 627 dev_dbg(&client->dev, "%s\n", __func__); 628 dev_dbg(&client->dev, "IRQ: %d\n", client->irq); 629 630 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 631 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n"); 632 return -ENODEV; 633 } 634 635 phy = devm_kzalloc(&client->dev, sizeof(struct st21nfca_i2c_phy), 636 GFP_KERNEL); 637 if (!phy) { 638 nfc_err(&client->dev, 639 "Cannot allocate memory for st21nfca i2c phy.\n"); 640 return -ENOMEM; 641 } 642 643 phy->i2c_dev = client; 644 phy->pending_skb = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE * 2, GFP_KERNEL); 645 if (phy->pending_skb == NULL) 646 return -ENOMEM; 647 648 phy->current_read_len = 0; 649 phy->crc_trials = 0; 650 mutex_init(&phy->phy_lock); 651 i2c_set_clientdata(client, phy); 652 653 pdata = client->dev.platform_data; 654 if (!pdata && client->dev.of_node) { 655 r = st21nfca_hci_i2c_of_request_resources(client); 656 if (r) { 657 nfc_err(&client->dev, "No platform data\n"); 658 return r; 659 } 660 } else if (pdata) { 661 r = st21nfca_hci_i2c_request_resources(client); 662 if (r) { 663 nfc_err(&client->dev, "Cannot get platform resources\n"); 664 return r; 665 } 666 } else { 667 nfc_err(&client->dev, "st21nfca platform resources not available\n"); 668 return -ENODEV; 669 } 670 671 r = st21nfca_hci_platform_init(phy); 672 if (r < 0) { 673 nfc_err(&client->dev, "Unable to reboot st21nfca\n"); 674 return -ENODEV; 675 } 676 677 r = devm_request_threaded_irq(&client->dev, client->irq, NULL, 678 st21nfca_hci_irq_thread_fn, 679 phy->irq_polarity | IRQF_ONESHOT, 680 ST21NFCA_HCI_DRIVER_NAME, phy); 681 if (r < 0) { 682 nfc_err(&client->dev, "Unable to register IRQ handler\n"); 683 return r; 684 } 685 686 return st21nfca_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME, 687 ST21NFCA_FRAME_HEADROOM, ST21NFCA_FRAME_TAILROOM, 688 ST21NFCA_HCI_LLC_MAX_PAYLOAD, &phy->hdev); 689 } 690 691 static int st21nfca_hci_i2c_remove(struct i2c_client *client) 692 { 693 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 694 695 dev_dbg(&client->dev, "%s\n", __func__); 696 697 st21nfca_hci_remove(phy->hdev); 698 699 if (phy->powered) 700 st21nfca_hci_i2c_disable(phy); 701 702 return 0; 703 } 704 705 static const struct of_device_id of_st21nfca_i2c_match[] = { 706 { .compatible = "st,st21nfca_i2c", }, 707 {} 708 }; 709 710 static struct i2c_driver st21nfca_hci_i2c_driver = { 711 .driver = { 712 .owner = THIS_MODULE, 713 .name = ST21NFCA_HCI_I2C_DRIVER_NAME, 714 .owner = THIS_MODULE, 715 .of_match_table = of_match_ptr(of_st21nfca_i2c_match), 716 }, 717 .probe = st21nfca_hci_i2c_probe, 718 .id_table = st21nfca_hci_i2c_id_table, 719 .remove = st21nfca_hci_i2c_remove, 720 }; 721 722 module_i2c_driver(st21nfca_hci_i2c_driver); 723 724 MODULE_LICENSE("GPL"); 725 MODULE_DESCRIPTION(DRIVER_DESC); 726