1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Silicon Labs C2 port core Linux support 4 * 5 * Copyright (c) 2007 Rodolfo Giometti <giometti@linux.it> 6 * Copyright (c) 2007 Eurotech S.p.A. <info@eurotech.it> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/init.h> 11 #include <linux/device.h> 12 #include <linux/errno.h> 13 #include <linux/err.h> 14 #include <linux/kernel.h> 15 #include <linux/ctype.h> 16 #include <linux/delay.h> 17 #include <linux/idr.h> 18 #include <linux/sched.h> 19 #include <linux/slab.h> 20 21 #include <linux/c2port.h> 22 23 #define DRIVER_NAME "c2port" 24 #define DRIVER_VERSION "0.51.0" 25 26 static DEFINE_SPINLOCK(c2port_idr_lock); 27 static DEFINE_IDR(c2port_idr); 28 29 /* 30 * Local variables 31 */ 32 33 static struct class *c2port_class; 34 35 /* 36 * C2 registers & commands defines 37 */ 38 39 /* C2 registers */ 40 #define C2PORT_DEVICEID 0x00 41 #define C2PORT_REVID 0x01 42 #define C2PORT_FPCTL 0x02 43 #define C2PORT_FPDAT 0xB4 44 45 /* C2 interface commands */ 46 #define C2PORT_GET_VERSION 0x01 47 #define C2PORT_DEVICE_ERASE 0x03 48 #define C2PORT_BLOCK_READ 0x06 49 #define C2PORT_BLOCK_WRITE 0x07 50 #define C2PORT_PAGE_ERASE 0x08 51 52 /* C2 status return codes */ 53 #define C2PORT_INVALID_COMMAND 0x00 54 #define C2PORT_COMMAND_FAILED 0x02 55 #define C2PORT_COMMAND_OK 0x0d 56 57 /* 58 * C2 port low level signal managements 59 */ 60 61 static void c2port_reset(struct c2port_device *dev) 62 { 63 struct c2port_ops *ops = dev->ops; 64 65 /* To reset the device we have to keep clock line low for at least 66 * 20us. 67 */ 68 local_irq_disable(); 69 ops->c2ck_set(dev, 0); 70 udelay(25); 71 ops->c2ck_set(dev, 1); 72 local_irq_enable(); 73 74 udelay(1); 75 } 76 77 static void c2port_strobe_ck(struct c2port_device *dev) 78 { 79 struct c2port_ops *ops = dev->ops; 80 81 /* During hi-low-hi transition we disable local IRQs to avoid 82 * interructions since C2 port specification says that it must be 83 * shorter than 5us, otherwise the microcontroller may consider 84 * it as a reset signal! 85 */ 86 local_irq_disable(); 87 ops->c2ck_set(dev, 0); 88 udelay(1); 89 ops->c2ck_set(dev, 1); 90 local_irq_enable(); 91 92 udelay(1); 93 } 94 95 /* 96 * C2 port basic functions 97 */ 98 99 static void c2port_write_ar(struct c2port_device *dev, u8 addr) 100 { 101 struct c2port_ops *ops = dev->ops; 102 int i; 103 104 /* START field */ 105 c2port_strobe_ck(dev); 106 107 /* INS field (11b, LSB first) */ 108 ops->c2d_dir(dev, 0); 109 ops->c2d_set(dev, 1); 110 c2port_strobe_ck(dev); 111 ops->c2d_set(dev, 1); 112 c2port_strobe_ck(dev); 113 114 /* ADDRESS field */ 115 for (i = 0; i < 8; i++) { 116 ops->c2d_set(dev, addr & 0x01); 117 c2port_strobe_ck(dev); 118 119 addr >>= 1; 120 } 121 122 /* STOP field */ 123 ops->c2d_dir(dev, 1); 124 c2port_strobe_ck(dev); 125 } 126 127 static int c2port_read_ar(struct c2port_device *dev, u8 *addr) 128 { 129 struct c2port_ops *ops = dev->ops; 130 int i; 131 132 /* START field */ 133 c2port_strobe_ck(dev); 134 135 /* INS field (10b, LSB first) */ 136 ops->c2d_dir(dev, 0); 137 ops->c2d_set(dev, 0); 138 c2port_strobe_ck(dev); 139 ops->c2d_set(dev, 1); 140 c2port_strobe_ck(dev); 141 142 /* ADDRESS field */ 143 ops->c2d_dir(dev, 1); 144 *addr = 0; 145 for (i = 0; i < 8; i++) { 146 *addr >>= 1; /* shift in 8-bit ADDRESS field LSB first */ 147 148 c2port_strobe_ck(dev); 149 if (ops->c2d_get(dev)) 150 *addr |= 0x80; 151 } 152 153 /* STOP field */ 154 c2port_strobe_ck(dev); 155 156 return 0; 157 } 158 159 static int c2port_write_dr(struct c2port_device *dev, u8 data) 160 { 161 struct c2port_ops *ops = dev->ops; 162 int timeout, i; 163 164 /* START field */ 165 c2port_strobe_ck(dev); 166 167 /* INS field (01b, LSB first) */ 168 ops->c2d_dir(dev, 0); 169 ops->c2d_set(dev, 1); 170 c2port_strobe_ck(dev); 171 ops->c2d_set(dev, 0); 172 c2port_strobe_ck(dev); 173 174 /* LENGTH field (00b, LSB first -> 1 byte) */ 175 ops->c2d_set(dev, 0); 176 c2port_strobe_ck(dev); 177 ops->c2d_set(dev, 0); 178 c2port_strobe_ck(dev); 179 180 /* DATA field */ 181 for (i = 0; i < 8; i++) { 182 ops->c2d_set(dev, data & 0x01); 183 c2port_strobe_ck(dev); 184 185 data >>= 1; 186 } 187 188 /* WAIT field */ 189 ops->c2d_dir(dev, 1); 190 timeout = 20; 191 do { 192 c2port_strobe_ck(dev); 193 if (ops->c2d_get(dev)) 194 break; 195 196 udelay(1); 197 } while (--timeout > 0); 198 if (timeout == 0) 199 return -EIO; 200 201 /* STOP field */ 202 c2port_strobe_ck(dev); 203 204 return 0; 205 } 206 207 static int c2port_read_dr(struct c2port_device *dev, u8 *data) 208 { 209 struct c2port_ops *ops = dev->ops; 210 int timeout, i; 211 212 /* START field */ 213 c2port_strobe_ck(dev); 214 215 /* INS field (00b, LSB first) */ 216 ops->c2d_dir(dev, 0); 217 ops->c2d_set(dev, 0); 218 c2port_strobe_ck(dev); 219 ops->c2d_set(dev, 0); 220 c2port_strobe_ck(dev); 221 222 /* LENGTH field (00b, LSB first -> 1 byte) */ 223 ops->c2d_set(dev, 0); 224 c2port_strobe_ck(dev); 225 ops->c2d_set(dev, 0); 226 c2port_strobe_ck(dev); 227 228 /* WAIT field */ 229 ops->c2d_dir(dev, 1); 230 timeout = 20; 231 do { 232 c2port_strobe_ck(dev); 233 if (ops->c2d_get(dev)) 234 break; 235 236 udelay(1); 237 } while (--timeout > 0); 238 if (timeout == 0) 239 return -EIO; 240 241 /* DATA field */ 242 *data = 0; 243 for (i = 0; i < 8; i++) { 244 *data >>= 1; /* shift in 8-bit DATA field LSB first */ 245 246 c2port_strobe_ck(dev); 247 if (ops->c2d_get(dev)) 248 *data |= 0x80; 249 } 250 251 /* STOP field */ 252 c2port_strobe_ck(dev); 253 254 return 0; 255 } 256 257 static int c2port_poll_in_busy(struct c2port_device *dev) 258 { 259 u8 addr; 260 int ret, timeout = 20; 261 262 do { 263 ret = (c2port_read_ar(dev, &addr)); 264 if (ret < 0) 265 return -EIO; 266 267 if (!(addr & 0x02)) 268 break; 269 270 udelay(1); 271 } while (--timeout > 0); 272 if (timeout == 0) 273 return -EIO; 274 275 return 0; 276 } 277 278 static int c2port_poll_out_ready(struct c2port_device *dev) 279 { 280 u8 addr; 281 int ret, timeout = 10000; /* erase flash needs long time... */ 282 283 do { 284 ret = (c2port_read_ar(dev, &addr)); 285 if (ret < 0) 286 return -EIO; 287 288 if (addr & 0x01) 289 break; 290 291 udelay(1); 292 } while (--timeout > 0); 293 if (timeout == 0) 294 return -EIO; 295 296 return 0; 297 } 298 299 /* 300 * sysfs methods 301 */ 302 303 static ssize_t c2port_show_name(struct device *dev, 304 struct device_attribute *attr, char *buf) 305 { 306 struct c2port_device *c2dev = dev_get_drvdata(dev); 307 308 return sprintf(buf, "%s\n", c2dev->name); 309 } 310 static DEVICE_ATTR(name, 0444, c2port_show_name, NULL); 311 312 static ssize_t c2port_show_flash_blocks_num(struct device *dev, 313 struct device_attribute *attr, char *buf) 314 { 315 struct c2port_device *c2dev = dev_get_drvdata(dev); 316 struct c2port_ops *ops = c2dev->ops; 317 318 return sprintf(buf, "%d\n", ops->blocks_num); 319 } 320 static DEVICE_ATTR(flash_blocks_num, 0444, c2port_show_flash_blocks_num, NULL); 321 322 static ssize_t c2port_show_flash_block_size(struct device *dev, 323 struct device_attribute *attr, char *buf) 324 { 325 struct c2port_device *c2dev = dev_get_drvdata(dev); 326 struct c2port_ops *ops = c2dev->ops; 327 328 return sprintf(buf, "%d\n", ops->block_size); 329 } 330 static DEVICE_ATTR(flash_block_size, 0444, c2port_show_flash_block_size, NULL); 331 332 static ssize_t c2port_show_flash_size(struct device *dev, 333 struct device_attribute *attr, char *buf) 334 { 335 struct c2port_device *c2dev = dev_get_drvdata(dev); 336 struct c2port_ops *ops = c2dev->ops; 337 338 return sprintf(buf, "%d\n", ops->blocks_num * ops->block_size); 339 } 340 static DEVICE_ATTR(flash_size, 0444, c2port_show_flash_size, NULL); 341 342 static ssize_t access_show(struct device *dev, struct device_attribute *attr, 343 char *buf) 344 { 345 struct c2port_device *c2dev = dev_get_drvdata(dev); 346 347 return sprintf(buf, "%d\n", c2dev->access); 348 } 349 350 static ssize_t access_store(struct device *dev, struct device_attribute *attr, 351 const char *buf, size_t count) 352 { 353 struct c2port_device *c2dev = dev_get_drvdata(dev); 354 struct c2port_ops *ops = c2dev->ops; 355 int status, ret; 356 357 ret = sscanf(buf, "%d", &status); 358 if (ret != 1) 359 return -EINVAL; 360 361 mutex_lock(&c2dev->mutex); 362 363 c2dev->access = !!status; 364 365 /* If access is "on" clock should be HIGH _before_ setting the line 366 * as output and data line should be set as INPUT anyway */ 367 if (c2dev->access) 368 ops->c2ck_set(c2dev, 1); 369 ops->access(c2dev, c2dev->access); 370 if (c2dev->access) 371 ops->c2d_dir(c2dev, 1); 372 373 mutex_unlock(&c2dev->mutex); 374 375 return count; 376 } 377 static DEVICE_ATTR_RW(access); 378 379 static ssize_t c2port_store_reset(struct device *dev, 380 struct device_attribute *attr, 381 const char *buf, size_t count) 382 { 383 struct c2port_device *c2dev = dev_get_drvdata(dev); 384 385 /* Check the device access status */ 386 if (!c2dev->access) 387 return -EBUSY; 388 389 mutex_lock(&c2dev->mutex); 390 391 c2port_reset(c2dev); 392 c2dev->flash_access = 0; 393 394 mutex_unlock(&c2dev->mutex); 395 396 return count; 397 } 398 static DEVICE_ATTR(reset, 0200, NULL, c2port_store_reset); 399 400 static ssize_t __c2port_show_dev_id(struct c2port_device *dev, char *buf) 401 { 402 u8 data; 403 int ret; 404 405 /* Select DEVICEID register for C2 data register accesses */ 406 c2port_write_ar(dev, C2PORT_DEVICEID); 407 408 /* Read and return the device ID register */ 409 ret = c2port_read_dr(dev, &data); 410 if (ret < 0) 411 return ret; 412 413 return sprintf(buf, "%d\n", data); 414 } 415 416 static ssize_t c2port_show_dev_id(struct device *dev, 417 struct device_attribute *attr, char *buf) 418 { 419 struct c2port_device *c2dev = dev_get_drvdata(dev); 420 ssize_t ret; 421 422 /* Check the device access status */ 423 if (!c2dev->access) 424 return -EBUSY; 425 426 mutex_lock(&c2dev->mutex); 427 ret = __c2port_show_dev_id(c2dev, buf); 428 mutex_unlock(&c2dev->mutex); 429 430 if (ret < 0) 431 dev_err(dev, "cannot read from %s\n", c2dev->name); 432 433 return ret; 434 } 435 static DEVICE_ATTR(dev_id, 0444, c2port_show_dev_id, NULL); 436 437 static ssize_t __c2port_show_rev_id(struct c2port_device *dev, char *buf) 438 { 439 u8 data; 440 int ret; 441 442 /* Select REVID register for C2 data register accesses */ 443 c2port_write_ar(dev, C2PORT_REVID); 444 445 /* Read and return the revision ID register */ 446 ret = c2port_read_dr(dev, &data); 447 if (ret < 0) 448 return ret; 449 450 return sprintf(buf, "%d\n", data); 451 } 452 453 static ssize_t c2port_show_rev_id(struct device *dev, 454 struct device_attribute *attr, char *buf) 455 { 456 struct c2port_device *c2dev = dev_get_drvdata(dev); 457 ssize_t ret; 458 459 /* Check the device access status */ 460 if (!c2dev->access) 461 return -EBUSY; 462 463 mutex_lock(&c2dev->mutex); 464 ret = __c2port_show_rev_id(c2dev, buf); 465 mutex_unlock(&c2dev->mutex); 466 467 if (ret < 0) 468 dev_err(c2dev->dev, "cannot read from %s\n", c2dev->name); 469 470 return ret; 471 } 472 static DEVICE_ATTR(rev_id, 0444, c2port_show_rev_id, NULL); 473 474 static ssize_t c2port_show_flash_access(struct device *dev, 475 struct device_attribute *attr, char *buf) 476 { 477 struct c2port_device *c2dev = dev_get_drvdata(dev); 478 479 return sprintf(buf, "%d\n", c2dev->flash_access); 480 } 481 482 static ssize_t __c2port_store_flash_access(struct c2port_device *dev, 483 int status) 484 { 485 int ret; 486 487 /* Check the device access status */ 488 if (!dev->access) 489 return -EBUSY; 490 491 dev->flash_access = !!status; 492 493 /* If flash_access is off we have nothing to do... */ 494 if (dev->flash_access == 0) 495 return 0; 496 497 /* Target the C2 flash programming control register for C2 data 498 * register access */ 499 c2port_write_ar(dev, C2PORT_FPCTL); 500 501 /* Write the first keycode to enable C2 Flash programming */ 502 ret = c2port_write_dr(dev, 0x02); 503 if (ret < 0) 504 return ret; 505 506 /* Write the second keycode to enable C2 Flash programming */ 507 ret = c2port_write_dr(dev, 0x01); 508 if (ret < 0) 509 return ret; 510 511 /* Delay for at least 20ms to ensure the target is ready for 512 * C2 flash programming */ 513 mdelay(25); 514 515 return 0; 516 } 517 518 static ssize_t c2port_store_flash_access(struct device *dev, 519 struct device_attribute *attr, 520 const char *buf, size_t count) 521 { 522 struct c2port_device *c2dev = dev_get_drvdata(dev); 523 int status; 524 ssize_t ret; 525 526 ret = sscanf(buf, "%d", &status); 527 if (ret != 1) 528 return -EINVAL; 529 530 mutex_lock(&c2dev->mutex); 531 ret = __c2port_store_flash_access(c2dev, status); 532 mutex_unlock(&c2dev->mutex); 533 534 if (ret < 0) { 535 dev_err(c2dev->dev, "cannot enable %s flash programming\n", 536 c2dev->name); 537 return ret; 538 } 539 540 return count; 541 } 542 static DEVICE_ATTR(flash_access, 0644, c2port_show_flash_access, 543 c2port_store_flash_access); 544 545 static ssize_t __c2port_write_flash_erase(struct c2port_device *dev) 546 { 547 u8 status; 548 int ret; 549 550 /* Target the C2 flash programming data register for C2 data register 551 * access. 552 */ 553 c2port_write_ar(dev, C2PORT_FPDAT); 554 555 /* Send device erase command */ 556 c2port_write_dr(dev, C2PORT_DEVICE_ERASE); 557 558 /* Wait for input acknowledge */ 559 ret = c2port_poll_in_busy(dev); 560 if (ret < 0) 561 return ret; 562 563 /* Should check status before starting FLASH access sequence */ 564 565 /* Wait for status information */ 566 ret = c2port_poll_out_ready(dev); 567 if (ret < 0) 568 return ret; 569 570 /* Read flash programming interface status */ 571 ret = c2port_read_dr(dev, &status); 572 if (ret < 0) 573 return ret; 574 if (status != C2PORT_COMMAND_OK) 575 return -EBUSY; 576 577 /* Send a three-byte arming sequence to enable the device erase. 578 * If the sequence is not received correctly, the command will be 579 * ignored. 580 * Sequence is: 0xde, 0xad, 0xa5. 581 */ 582 c2port_write_dr(dev, 0xde); 583 ret = c2port_poll_in_busy(dev); 584 if (ret < 0) 585 return ret; 586 c2port_write_dr(dev, 0xad); 587 ret = c2port_poll_in_busy(dev); 588 if (ret < 0) 589 return ret; 590 c2port_write_dr(dev, 0xa5); 591 ret = c2port_poll_in_busy(dev); 592 if (ret < 0) 593 return ret; 594 595 ret = c2port_poll_out_ready(dev); 596 if (ret < 0) 597 return ret; 598 599 return 0; 600 } 601 602 static ssize_t c2port_store_flash_erase(struct device *dev, 603 struct device_attribute *attr, 604 const char *buf, size_t count) 605 { 606 struct c2port_device *c2dev = dev_get_drvdata(dev); 607 int ret; 608 609 /* Check the device and flash access status */ 610 if (!c2dev->access || !c2dev->flash_access) 611 return -EBUSY; 612 613 mutex_lock(&c2dev->mutex); 614 ret = __c2port_write_flash_erase(c2dev); 615 mutex_unlock(&c2dev->mutex); 616 617 if (ret < 0) { 618 dev_err(c2dev->dev, "cannot erase %s flash\n", c2dev->name); 619 return ret; 620 } 621 622 return count; 623 } 624 static DEVICE_ATTR(flash_erase, 0200, NULL, c2port_store_flash_erase); 625 626 static ssize_t __c2port_read_flash_data(struct c2port_device *dev, 627 char *buffer, loff_t offset, size_t count) 628 { 629 struct c2port_ops *ops = dev->ops; 630 u8 status, nread = 128; 631 int i, ret; 632 633 /* Check for flash end */ 634 if (offset >= ops->block_size * ops->blocks_num) 635 return 0; 636 637 if (ops->block_size * ops->blocks_num - offset < nread) 638 nread = ops->block_size * ops->blocks_num - offset; 639 if (count < nread) 640 nread = count; 641 if (nread == 0) 642 return nread; 643 644 /* Target the C2 flash programming data register for C2 data register 645 * access */ 646 c2port_write_ar(dev, C2PORT_FPDAT); 647 648 /* Send flash block read command */ 649 c2port_write_dr(dev, C2PORT_BLOCK_READ); 650 651 /* Wait for input acknowledge */ 652 ret = c2port_poll_in_busy(dev); 653 if (ret < 0) 654 return ret; 655 656 /* Should check status before starting FLASH access sequence */ 657 658 /* Wait for status information */ 659 ret = c2port_poll_out_ready(dev); 660 if (ret < 0) 661 return ret; 662 663 /* Read flash programming interface status */ 664 ret = c2port_read_dr(dev, &status); 665 if (ret < 0) 666 return ret; 667 if (status != C2PORT_COMMAND_OK) 668 return -EBUSY; 669 670 /* Send address high byte */ 671 c2port_write_dr(dev, offset >> 8); 672 ret = c2port_poll_in_busy(dev); 673 if (ret < 0) 674 return ret; 675 676 /* Send address low byte */ 677 c2port_write_dr(dev, offset & 0x00ff); 678 ret = c2port_poll_in_busy(dev); 679 if (ret < 0) 680 return ret; 681 682 /* Send address block size */ 683 c2port_write_dr(dev, nread); 684 ret = c2port_poll_in_busy(dev); 685 if (ret < 0) 686 return ret; 687 688 /* Should check status before reading FLASH block */ 689 690 /* Wait for status information */ 691 ret = c2port_poll_out_ready(dev); 692 if (ret < 0) 693 return ret; 694 695 /* Read flash programming interface status */ 696 ret = c2port_read_dr(dev, &status); 697 if (ret < 0) 698 return ret; 699 if (status != C2PORT_COMMAND_OK) 700 return -EBUSY; 701 702 /* Read flash block */ 703 for (i = 0; i < nread; i++) { 704 ret = c2port_poll_out_ready(dev); 705 if (ret < 0) 706 return ret; 707 708 ret = c2port_read_dr(dev, buffer+i); 709 if (ret < 0) 710 return ret; 711 } 712 713 return nread; 714 } 715 716 static ssize_t c2port_read_flash_data(struct file *filp, struct kobject *kobj, 717 struct bin_attribute *attr, 718 char *buffer, loff_t offset, size_t count) 719 { 720 struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj)); 721 ssize_t ret; 722 723 /* Check the device and flash access status */ 724 if (!c2dev->access || !c2dev->flash_access) 725 return -EBUSY; 726 727 mutex_lock(&c2dev->mutex); 728 ret = __c2port_read_flash_data(c2dev, buffer, offset, count); 729 mutex_unlock(&c2dev->mutex); 730 731 if (ret < 0) 732 dev_err(c2dev->dev, "cannot read %s flash\n", c2dev->name); 733 734 return ret; 735 } 736 737 static ssize_t __c2port_write_flash_data(struct c2port_device *dev, 738 char *buffer, loff_t offset, size_t count) 739 { 740 struct c2port_ops *ops = dev->ops; 741 u8 status, nwrite = 128; 742 int i, ret; 743 744 if (nwrite > count) 745 nwrite = count; 746 if (ops->block_size * ops->blocks_num - offset < nwrite) 747 nwrite = ops->block_size * ops->blocks_num - offset; 748 749 /* Check for flash end */ 750 if (offset >= ops->block_size * ops->blocks_num) 751 return -EINVAL; 752 753 /* Target the C2 flash programming data register for C2 data register 754 * access */ 755 c2port_write_ar(dev, C2PORT_FPDAT); 756 757 /* Send flash block write command */ 758 c2port_write_dr(dev, C2PORT_BLOCK_WRITE); 759 760 /* Wait for input acknowledge */ 761 ret = c2port_poll_in_busy(dev); 762 if (ret < 0) 763 return ret; 764 765 /* Should check status before starting FLASH access sequence */ 766 767 /* Wait for status information */ 768 ret = c2port_poll_out_ready(dev); 769 if (ret < 0) 770 return ret; 771 772 /* Read flash programming interface status */ 773 ret = c2port_read_dr(dev, &status); 774 if (ret < 0) 775 return ret; 776 if (status != C2PORT_COMMAND_OK) 777 return -EBUSY; 778 779 /* Send address high byte */ 780 c2port_write_dr(dev, offset >> 8); 781 ret = c2port_poll_in_busy(dev); 782 if (ret < 0) 783 return ret; 784 785 /* Send address low byte */ 786 c2port_write_dr(dev, offset & 0x00ff); 787 ret = c2port_poll_in_busy(dev); 788 if (ret < 0) 789 return ret; 790 791 /* Send address block size */ 792 c2port_write_dr(dev, nwrite); 793 ret = c2port_poll_in_busy(dev); 794 if (ret < 0) 795 return ret; 796 797 /* Should check status before writing FLASH block */ 798 799 /* Wait for status information */ 800 ret = c2port_poll_out_ready(dev); 801 if (ret < 0) 802 return ret; 803 804 /* Read flash programming interface status */ 805 ret = c2port_read_dr(dev, &status); 806 if (ret < 0) 807 return ret; 808 if (status != C2PORT_COMMAND_OK) 809 return -EBUSY; 810 811 /* Write flash block */ 812 for (i = 0; i < nwrite; i++) { 813 ret = c2port_write_dr(dev, *(buffer+i)); 814 if (ret < 0) 815 return ret; 816 817 ret = c2port_poll_in_busy(dev); 818 if (ret < 0) 819 return ret; 820 821 } 822 823 /* Wait for last flash write to complete */ 824 ret = c2port_poll_out_ready(dev); 825 if (ret < 0) 826 return ret; 827 828 return nwrite; 829 } 830 831 static ssize_t c2port_write_flash_data(struct file *filp, struct kobject *kobj, 832 struct bin_attribute *attr, 833 char *buffer, loff_t offset, size_t count) 834 { 835 struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj)); 836 int ret; 837 838 /* Check the device access status */ 839 if (!c2dev->access || !c2dev->flash_access) 840 return -EBUSY; 841 842 mutex_lock(&c2dev->mutex); 843 ret = __c2port_write_flash_data(c2dev, buffer, offset, count); 844 mutex_unlock(&c2dev->mutex); 845 846 if (ret < 0) 847 dev_err(c2dev->dev, "cannot write %s flash\n", c2dev->name); 848 849 return ret; 850 } 851 /* size is computed at run-time */ 852 static BIN_ATTR(flash_data, 0644, c2port_read_flash_data, 853 c2port_write_flash_data, 0); 854 855 /* 856 * Class attributes 857 */ 858 static struct attribute *c2port_attrs[] = { 859 &dev_attr_name.attr, 860 &dev_attr_flash_blocks_num.attr, 861 &dev_attr_flash_block_size.attr, 862 &dev_attr_flash_size.attr, 863 &dev_attr_access.attr, 864 &dev_attr_reset.attr, 865 &dev_attr_dev_id.attr, 866 &dev_attr_rev_id.attr, 867 &dev_attr_flash_access.attr, 868 &dev_attr_flash_erase.attr, 869 NULL, 870 }; 871 872 static struct bin_attribute *c2port_bin_attrs[] = { 873 &bin_attr_flash_data, 874 NULL, 875 }; 876 877 static const struct attribute_group c2port_group = { 878 .attrs = c2port_attrs, 879 .bin_attrs = c2port_bin_attrs, 880 }; 881 882 static const struct attribute_group *c2port_groups[] = { 883 &c2port_group, 884 NULL, 885 }; 886 887 /* 888 * Exported functions 889 */ 890 891 struct c2port_device *c2port_device_register(char *name, 892 struct c2port_ops *ops, void *devdata) 893 { 894 struct c2port_device *c2dev; 895 int ret; 896 897 if (unlikely(!ops) || unlikely(!ops->access) || \ 898 unlikely(!ops->c2d_dir) || unlikely(!ops->c2ck_set) || \ 899 unlikely(!ops->c2d_get) || unlikely(!ops->c2d_set)) 900 return ERR_PTR(-EINVAL); 901 902 c2dev = kzalloc(sizeof(struct c2port_device), GFP_KERNEL); 903 if (unlikely(!c2dev)) 904 return ERR_PTR(-ENOMEM); 905 906 idr_preload(GFP_KERNEL); 907 spin_lock_irq(&c2port_idr_lock); 908 ret = idr_alloc(&c2port_idr, c2dev, 0, 0, GFP_NOWAIT); 909 spin_unlock_irq(&c2port_idr_lock); 910 idr_preload_end(); 911 912 if (ret < 0) 913 goto error_idr_alloc; 914 c2dev->id = ret; 915 916 bin_attr_flash_data.size = ops->blocks_num * ops->block_size; 917 918 c2dev->dev = device_create(c2port_class, NULL, 0, c2dev, 919 "c2port%d", c2dev->id); 920 if (IS_ERR(c2dev->dev)) { 921 ret = PTR_ERR(c2dev->dev); 922 goto error_device_create; 923 } 924 dev_set_drvdata(c2dev->dev, c2dev); 925 926 strncpy(c2dev->name, name, C2PORT_NAME_LEN - 1); 927 c2dev->ops = ops; 928 mutex_init(&c2dev->mutex); 929 930 /* By default C2 port access is off */ 931 c2dev->access = c2dev->flash_access = 0; 932 ops->access(c2dev, 0); 933 934 dev_info(c2dev->dev, "C2 port %s added\n", name); 935 dev_info(c2dev->dev, "%s flash has %d blocks x %d bytes " 936 "(%d bytes total)\n", 937 name, ops->blocks_num, ops->block_size, 938 ops->blocks_num * ops->block_size); 939 940 return c2dev; 941 942 error_device_create: 943 spin_lock_irq(&c2port_idr_lock); 944 idr_remove(&c2port_idr, c2dev->id); 945 spin_unlock_irq(&c2port_idr_lock); 946 947 error_idr_alloc: 948 kfree(c2dev); 949 950 return ERR_PTR(ret); 951 } 952 EXPORT_SYMBOL(c2port_device_register); 953 954 void c2port_device_unregister(struct c2port_device *c2dev) 955 { 956 if (!c2dev) 957 return; 958 959 dev_info(c2dev->dev, "C2 port %s removed\n", c2dev->name); 960 961 spin_lock_irq(&c2port_idr_lock); 962 idr_remove(&c2port_idr, c2dev->id); 963 spin_unlock_irq(&c2port_idr_lock); 964 965 device_destroy(c2port_class, c2dev->id); 966 967 kfree(c2dev); 968 } 969 EXPORT_SYMBOL(c2port_device_unregister); 970 971 /* 972 * Module stuff 973 */ 974 975 static int __init c2port_init(void) 976 { 977 printk(KERN_INFO "Silicon Labs C2 port support v. " DRIVER_VERSION 978 " - (C) 2007 Rodolfo Giometti\n"); 979 980 c2port_class = class_create("c2port"); 981 if (IS_ERR(c2port_class)) { 982 printk(KERN_ERR "c2port: failed to allocate class\n"); 983 return PTR_ERR(c2port_class); 984 } 985 c2port_class->dev_groups = c2port_groups; 986 987 return 0; 988 } 989 990 static void __exit c2port_exit(void) 991 { 992 class_destroy(c2port_class); 993 } 994 995 module_init(c2port_init); 996 module_exit(c2port_exit); 997 998 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); 999 MODULE_DESCRIPTION("Silicon Labs C2 port support v. " DRIVER_VERSION); 1000 MODULE_LICENSE("GPL"); 1001