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; 274 275 if (buf[len + 1] == ST21NFCA_SOF_EOF) 276 return 0; 277 278 for (len = 1; len < buflen && buf[len] != ST21NFCA_SOF_EOF; len++) 279 ; 280 281 return len; 282 } 283 284 static int check_crc(u8 *buf, int buflen) 285 { 286 u16 crc; 287 288 crc = crc_ccitt(0xffff, buf, buflen - 2); 289 crc = ~crc; 290 291 if (buf[buflen - 2] != (crc & 0xff) || buf[buflen - 1] != (crc >> 8)) { 292 pr_err(ST21NFCA_HCI_DRIVER_NAME 293 ": CRC error 0x%x != 0x%x 0x%x\n", crc, buf[buflen - 1], 294 buf[buflen - 2]); 295 296 pr_info(DRIVER_DESC ": %s : BAD CRC\n", __func__); 297 print_hex_dump(KERN_DEBUG, "crc: ", DUMP_PREFIX_NONE, 298 16, 2, buf, buflen, false); 299 return -EPERM; 300 } 301 return 0; 302 } 303 304 /* 305 * Prepare received data for upper layer. 306 * Received data include byte stuffing, crc and sof/eof 307 * which is not usable by hci part. 308 * returns: 309 * frame size without sof/eof, header and byte stuffing 310 * -EBADMSG : frame was incorrect and discarded 311 */ 312 static int st21nfca_hci_i2c_repack(struct sk_buff *skb) 313 { 314 int i, j, r, size; 315 316 if (skb->len < 1 || (skb->len > 1 && skb->data[1] != 0)) 317 return -EBADMSG; 318 319 size = get_frame_size(skb->data, skb->len); 320 if (size > 0) { 321 skb_trim(skb, size); 322 /* remove ST21NFCA byte stuffing for upper layer */ 323 for (i = 1, j = 0; i < skb->len; i++) { 324 if (skb->data[i + j] == 325 (u8) ST21NFCA_ESCAPE_BYTE_STUFFING) { 326 skb->data[i] = skb->data[i + j + 1] 327 | ST21NFCA_BYTE_STUFFING_MASK; 328 i++; 329 j++; 330 } 331 skb->data[i] = skb->data[i + j]; 332 } 333 /* remove byte stuffing useless byte */ 334 skb_trim(skb, i - j); 335 /* remove ST21NFCA_SOF_EOF from head */ 336 skb_pull(skb, 1); 337 338 r = check_crc(skb->data, skb->len); 339 if (r != 0) { 340 i = 0; 341 return -EBADMSG; 342 } 343 344 /* remove headbyte */ 345 skb_pull(skb, 1); 346 /* remove crc. Byte Stuffing is already removed here */ 347 skb_trim(skb, skb->len - 2); 348 return skb->len; 349 } 350 return 0; 351 } 352 353 /* 354 * Reads an shdlc frame and returns it in a newly allocated sk_buff. Guarantees 355 * that i2c bus will be flushed and that next read will start on a new frame. 356 * returned skb contains only LLC header and payload. 357 * returns: 358 * frame size : if received frame is complete (find ST21NFCA_SOF_EOF at 359 * end of read) 360 * -EAGAIN : if received frame is incomplete (not find ST21NFCA_SOF_EOF 361 * at end of read) 362 * -EREMOTEIO : i2c read error (fatal) 363 * -EBADMSG : frame was incorrect and discarded 364 * (value returned from st21nfca_hci_i2c_repack) 365 * -EIO : if no ST21NFCA_SOF_EOF is found after reaching 366 * the read length end sequence 367 */ 368 static int st21nfca_hci_i2c_read(struct st21nfca_i2c_phy *phy, 369 struct sk_buff *skb) 370 { 371 int r, i; 372 u8 len; 373 u8 buf[ST21NFCA_HCI_LLC_MAX_PAYLOAD]; 374 struct i2c_client *client = phy->i2c_dev; 375 376 if (phy->current_read_len < ARRAY_SIZE(len_seq)) { 377 len = len_seq[phy->current_read_len]; 378 379 /* 380 * Add retry mecanism 381 * Operation on I2C interface may fail in case of operation on 382 * RF or SWP interface 383 */ 384 r = 0; 385 mutex_lock(&phy->phy_lock); 386 for (i = 0; i < ARRAY_SIZE(wait_tab) && r <= 0; i++) { 387 r = i2c_master_recv(client, buf, len); 388 if (r < 0) 389 msleep(wait_tab[i]); 390 } 391 mutex_unlock(&phy->phy_lock); 392 393 if (r != len) { 394 phy->current_read_len = 0; 395 return -EREMOTEIO; 396 } 397 398 /* 399 * The first read sequence does not start with SOF. 400 * Data is corrupeted so we drop it. 401 */ 402 if (!phy->current_read_len && !IS_START_OF_FRAME(buf)) { 403 skb_trim(skb, 0); 404 phy->current_read_len = 0; 405 return -EIO; 406 } else if (phy->current_read_len && IS_START_OF_FRAME(buf)) { 407 /* 408 * Previous frame transmission was interrupted and 409 * the frame got repeated. 410 * Received frame start with ST21NFCA_SOF_EOF + 00. 411 */ 412 skb_trim(skb, 0); 413 phy->current_read_len = 0; 414 } 415 416 memcpy(skb_put(skb, len), buf, len); 417 418 if (skb->data[skb->len - 1] == ST21NFCA_SOF_EOF) { 419 phy->current_read_len = 0; 420 return st21nfca_hci_i2c_repack(skb); 421 } 422 phy->current_read_len++; 423 return -EAGAIN; 424 } 425 return -EIO; 426 } 427 428 /* 429 * Reads an shdlc frame from the chip. This is not as straightforward as it 430 * seems. The frame format is data-crc, and corruption can occur anywhere 431 * while transiting on i2c bus, such that we could read an invalid data. 432 * The tricky case is when we read a corrupted data or crc. We must detect 433 * this here in order to determine that data can be transmitted to the hci 434 * core. This is the reason why we check the crc here. 435 * The CLF will repeat a frame until we send a RR on that frame. 436 * 437 * On ST21NFCA, IRQ goes in idle when read starts. As no size information are 438 * available in the incoming data, other IRQ might come. Every IRQ will trigger 439 * a read sequence with different length and will fill the current frame. 440 * The reception is complete once we reach a ST21NFCA_SOF_EOF. 441 */ 442 static irqreturn_t st21nfca_hci_irq_thread_fn(int irq, void *phy_id) 443 { 444 struct st21nfca_i2c_phy *phy = phy_id; 445 struct i2c_client *client; 446 447 int r; 448 449 if (!phy || irq != phy->i2c_dev->irq) { 450 WARN_ON_ONCE(1); 451 return IRQ_NONE; 452 } 453 454 client = phy->i2c_dev; 455 dev_dbg(&client->dev, "IRQ\n"); 456 457 if (phy->hard_fault != 0) 458 return IRQ_HANDLED; 459 460 r = st21nfca_hci_i2c_read(phy, phy->pending_skb); 461 if (r == -EREMOTEIO) { 462 phy->hard_fault = r; 463 464 nfc_hci_recv_frame(phy->hdev, NULL); 465 466 return IRQ_HANDLED; 467 } else if (r == -EAGAIN || r == -EIO) { 468 return IRQ_HANDLED; 469 } else if (r == -EBADMSG && phy->crc_trials < ARRAY_SIZE(wait_tab)) { 470 /* 471 * With ST21NFCA, only one interface (I2C, RF or SWP) 472 * may be active at a time. 473 * Having incorrect crc is usually due to i2c macrocell 474 * deactivation in the middle of a transmission. 475 * It may generate corrupted data on i2c. 476 * We give sometime to get i2c back. 477 * The complete frame will be repeated. 478 */ 479 msleep(wait_tab[phy->crc_trials]); 480 phy->crc_trials++; 481 phy->current_read_len = 0; 482 kfree_skb(phy->pending_skb); 483 } else if (r > 0) { 484 /* 485 * We succeeded to read data from the CLF and 486 * data is valid. 487 * Reset counter. 488 */ 489 nfc_hci_recv_frame(phy->hdev, phy->pending_skb); 490 phy->crc_trials = 0; 491 } else { 492 kfree_skb(phy->pending_skb); 493 } 494 495 phy->pending_skb = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE * 2, GFP_KERNEL); 496 if (phy->pending_skb == NULL) { 497 phy->hard_fault = -ENOMEM; 498 nfc_hci_recv_frame(phy->hdev, NULL); 499 } 500 501 return IRQ_HANDLED; 502 } 503 504 static struct nfc_phy_ops i2c_phy_ops = { 505 .write = st21nfca_hci_i2c_write, 506 .enable = st21nfca_hci_i2c_enable, 507 .disable = st21nfca_hci_i2c_disable, 508 }; 509 510 #ifdef CONFIG_OF 511 static int st21nfca_hci_i2c_of_request_resources(struct i2c_client *client) 512 { 513 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 514 struct device_node *pp; 515 int gpio; 516 int r; 517 518 pp = client->dev.of_node; 519 if (!pp) 520 return -ENODEV; 521 522 /* Get GPIO from device tree */ 523 gpio = of_get_named_gpio(pp, "enable-gpios", 0); 524 if (gpio < 0) { 525 nfc_err(&client->dev, "Failed to retrieve enable-gpios from device tree\n"); 526 return gpio; 527 } 528 529 /* GPIO request and configuration */ 530 r = devm_gpio_request_one(&client->dev, gpio, GPIOF_OUT_INIT_HIGH, 531 "clf_enable"); 532 if (r) { 533 nfc_err(&client->dev, "Failed to request enable pin\n"); 534 return -ENODEV; 535 } 536 537 phy->gpio_ena = gpio; 538 539 /* IRQ */ 540 r = irq_of_parse_and_map(pp, 0); 541 if (r < 0) { 542 nfc_err(&client->dev, "Unable to get irq, error: %d\n", r); 543 return r; 544 } 545 546 phy->irq_polarity = irq_get_trigger_type(r); 547 client->irq = r; 548 549 return 0; 550 } 551 #else 552 static int st21nfca_hci_i2c_of_request_resources(struct i2c_client *client) 553 { 554 return -ENODEV; 555 } 556 #endif 557 558 static int st21nfca_hci_i2c_request_resources(struct i2c_client *client) 559 { 560 struct st21nfca_nfc_platform_data *pdata; 561 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 562 int r; 563 int irq; 564 565 pdata = client->dev.platform_data; 566 if (pdata == NULL) { 567 nfc_err(&client->dev, "No platform data\n"); 568 return -EINVAL; 569 } 570 571 /* store for later use */ 572 phy->gpio_irq = pdata->gpio_irq; 573 phy->gpio_ena = pdata->gpio_ena; 574 phy->irq_polarity = pdata->irq_polarity; 575 576 r = devm_gpio_request_one(&client->dev, phy->gpio_irq, GPIOF_IN, 577 "wake_up"); 578 if (r) { 579 pr_err("%s : gpio_request failed\n", __FILE__); 580 return -ENODEV; 581 } 582 583 if (phy->gpio_ena > 0) { 584 r = devm_gpio_request_one(&client->dev, phy->gpio_ena, 585 GPIOF_OUT_INIT_HIGH, "clf_enable"); 586 if (r) { 587 pr_err("%s : ena gpio_request failed\n", __FILE__); 588 return -ENODEV; 589 } 590 } 591 592 /* IRQ */ 593 irq = gpio_to_irq(phy->gpio_irq); 594 if (irq < 0) { 595 nfc_err(&client->dev, 596 "Unable to get irq number for GPIO %d error %d\n", 597 phy->gpio_irq, r); 598 return -ENODEV; 599 } 600 client->irq = irq; 601 602 return 0; 603 } 604 605 static int st21nfca_hci_i2c_probe(struct i2c_client *client, 606 const struct i2c_device_id *id) 607 { 608 struct st21nfca_i2c_phy *phy; 609 struct st21nfca_nfc_platform_data *pdata; 610 int r; 611 612 dev_dbg(&client->dev, "%s\n", __func__); 613 dev_dbg(&client->dev, "IRQ: %d\n", client->irq); 614 615 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 616 nfc_err(&client->dev, "Need I2C_FUNC_I2C\n"); 617 return -ENODEV; 618 } 619 620 phy = devm_kzalloc(&client->dev, sizeof(struct st21nfca_i2c_phy), 621 GFP_KERNEL); 622 if (!phy) { 623 nfc_err(&client->dev, 624 "Cannot allocate memory for st21nfca i2c phy.\n"); 625 return -ENOMEM; 626 } 627 628 phy->i2c_dev = client; 629 phy->pending_skb = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE * 2, GFP_KERNEL); 630 if (phy->pending_skb == NULL) 631 return -ENOMEM; 632 633 phy->current_read_len = 0; 634 phy->crc_trials = 0; 635 mutex_init(&phy->phy_lock); 636 i2c_set_clientdata(client, phy); 637 638 pdata = client->dev.platform_data; 639 if (!pdata && client->dev.of_node) { 640 r = st21nfca_hci_i2c_of_request_resources(client); 641 if (r) { 642 nfc_err(&client->dev, "No platform data\n"); 643 return r; 644 } 645 } else if (pdata) { 646 r = st21nfca_hci_i2c_request_resources(client); 647 if (r) { 648 nfc_err(&client->dev, "Cannot get platform resources\n"); 649 return r; 650 } 651 } else { 652 nfc_err(&client->dev, "st21nfca platform resources not available\n"); 653 return -ENODEV; 654 } 655 656 r = st21nfca_hci_platform_init(phy); 657 if (r < 0) { 658 nfc_err(&client->dev, "Unable to reboot st21nfca\n"); 659 return -ENODEV; 660 } 661 662 r = devm_request_threaded_irq(&client->dev, client->irq, NULL, 663 st21nfca_hci_irq_thread_fn, 664 phy->irq_polarity | IRQF_ONESHOT, 665 ST21NFCA_HCI_DRIVER_NAME, phy); 666 if (r < 0) { 667 nfc_err(&client->dev, "Unable to register IRQ handler\n"); 668 return r; 669 } 670 671 return st21nfca_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME, 672 ST21NFCA_FRAME_HEADROOM, ST21NFCA_FRAME_TAILROOM, 673 ST21NFCA_HCI_LLC_MAX_PAYLOAD, &phy->hdev); 674 } 675 676 static int st21nfca_hci_i2c_remove(struct i2c_client *client) 677 { 678 struct st21nfca_i2c_phy *phy = i2c_get_clientdata(client); 679 680 dev_dbg(&client->dev, "%s\n", __func__); 681 682 st21nfca_hci_remove(phy->hdev); 683 684 if (phy->powered) 685 st21nfca_hci_i2c_disable(phy); 686 687 return 0; 688 } 689 690 static const struct of_device_id of_st21nfca_i2c_match[] = { 691 { .compatible = "st,st21nfca_i2c", }, 692 {} 693 }; 694 695 static struct i2c_driver st21nfca_hci_i2c_driver = { 696 .driver = { 697 .owner = THIS_MODULE, 698 .name = ST21NFCA_HCI_I2C_DRIVER_NAME, 699 .of_match_table = of_match_ptr(of_st21nfca_i2c_match), 700 }, 701 .probe = st21nfca_hci_i2c_probe, 702 .id_table = st21nfca_hci_i2c_id_table, 703 .remove = st21nfca_hci_i2c_remove, 704 }; 705 706 module_i2c_driver(st21nfca_hci_i2c_driver); 707 708 MODULE_LICENSE("GPL"); 709 MODULE_DESCRIPTION(DRIVER_DESC); 710