1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Generic driver for memory-mapped GPIO controllers. 4 * 5 * Copyright 2008 MontaVista Software, Inc. 6 * Copyright 2008,2010 Anton Vorontsov <cbouatmailru@gmail.com> 7 * 8 * ....``.```~~~~````.`.`.`.`.```````'',,,.........`````......`....... 9 * ...`` ```````.. 10 * ..The simplest form of a GPIO controller that the driver supports is`` 11 * `.just a single "data" register, where GPIO state can be read and/or ` 12 * `,..written. ,,..``~~~~ .....``.`.`.~~.```.`.........``````.``````` 13 * ````````` 14 ___ 15 _/~~|___/~| . ```~~~~~~ ___/___\___ ,~.`.`.`.`````.~~...,,,,... 16 __________|~$@~~~ %~ /o*o*o*o*o*o\ .. Implementing such a GPIO . 17 o ` ~~~~\___/~~~~ ` controller in FPGA is ,.` 18 `....trivial..'~`.```.``` 19 * ``````` 20 * .```````~~~~`..`.``.``. 21 * . The driver supports `... ,..```.`~~~```````````````....````.``,, 22 * . big-endian notation, just`. .. A bit more sophisticated controllers , 23 * . register the device with -be`. .with a pair of set/clear-bit registers , 24 * `.. suffix. ```~~`````....`.` . affecting the data register and the .` 25 * ``.`.``...``` ```.. output pins are also supported.` 26 * ^^ `````.`````````.,``~``~``~~`````` 27 * . ^^ 28 * ,..`.`.`...````````````......`.`.`.`.`.`..`.`.`.. 29 * .. The expectation is that in at least some cases . ,-~~~-, 30 * .this will be used with roll-your-own ASIC/FPGA .` \ / 31 * .logic in Verilog or VHDL. ~~~`````````..`````~~` \ / 32 * ..````````......``````````` \o_ 33 * | 34 * ^^ / \ 35 * 36 * ...`````~~`.....``.`..........``````.`.``.```........``. 37 * ` 8, 16, 32 and 64 bits registers are supported, and``. 38 * . the number of GPIOs is determined by the width of ~ 39 * .. the registers. ,............```.`.`..`.`.~~~.`.`.`~ 40 * `.......````.``` 41 */ 42 43 #include <linux/init.h> 44 #include <linux/err.h> 45 #include <linux/bug.h> 46 #include <linux/kernel.h> 47 #include <linux/module.h> 48 #include <linux/spinlock.h> 49 #include <linux/compiler.h> 50 #include <linux/types.h> 51 #include <linux/errno.h> 52 #include <linux/log2.h> 53 #include <linux/ioport.h> 54 #include <linux/io.h> 55 #include <linux/gpio/driver.h> 56 #include <linux/slab.h> 57 #include <linux/bitops.h> 58 #include <linux/platform_device.h> 59 #include <linux/mod_devicetable.h> 60 #include <linux/of.h> 61 #include <linux/of_device.h> 62 63 static void bgpio_write8(void __iomem *reg, unsigned long data) 64 { 65 writeb(data, reg); 66 } 67 68 static unsigned long bgpio_read8(void __iomem *reg) 69 { 70 return readb(reg); 71 } 72 73 static void bgpio_write16(void __iomem *reg, unsigned long data) 74 { 75 writew(data, reg); 76 } 77 78 static unsigned long bgpio_read16(void __iomem *reg) 79 { 80 return readw(reg); 81 } 82 83 static void bgpio_write32(void __iomem *reg, unsigned long data) 84 { 85 writel(data, reg); 86 } 87 88 static unsigned long bgpio_read32(void __iomem *reg) 89 { 90 return readl(reg); 91 } 92 93 #if BITS_PER_LONG >= 64 94 static void bgpio_write64(void __iomem *reg, unsigned long data) 95 { 96 writeq(data, reg); 97 } 98 99 static unsigned long bgpio_read64(void __iomem *reg) 100 { 101 return readq(reg); 102 } 103 #endif /* BITS_PER_LONG >= 64 */ 104 105 static void bgpio_write16be(void __iomem *reg, unsigned long data) 106 { 107 iowrite16be(data, reg); 108 } 109 110 static unsigned long bgpio_read16be(void __iomem *reg) 111 { 112 return ioread16be(reg); 113 } 114 115 static void bgpio_write32be(void __iomem *reg, unsigned long data) 116 { 117 iowrite32be(data, reg); 118 } 119 120 static unsigned long bgpio_read32be(void __iomem *reg) 121 { 122 return ioread32be(reg); 123 } 124 125 static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line) 126 { 127 if (gc->be_bits) 128 return BIT(gc->bgpio_bits - 1 - line); 129 return BIT(line); 130 } 131 132 static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio) 133 { 134 unsigned long pinmask = bgpio_line2mask(gc, gpio); 135 bool dir = !!(gc->bgpio_dir & pinmask); 136 137 if (dir) 138 return !!(gc->read_reg(gc->reg_set) & pinmask); 139 else 140 return !!(gc->read_reg(gc->reg_dat) & pinmask); 141 } 142 143 /* 144 * This assumes that the bits in the GPIO register are in native endianness. 145 * We only assign the function pointer if we have that. 146 */ 147 static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask, 148 unsigned long *bits) 149 { 150 unsigned long get_mask = 0; 151 unsigned long set_mask = 0; 152 153 /* Make sure we first clear any bits that are zero when we read the register */ 154 *bits &= ~*mask; 155 156 set_mask = *mask & gc->bgpio_dir; 157 get_mask = *mask & ~gc->bgpio_dir; 158 159 if (set_mask) 160 *bits |= gc->read_reg(gc->reg_set) & set_mask; 161 if (get_mask) 162 *bits |= gc->read_reg(gc->reg_dat) & get_mask; 163 164 return 0; 165 } 166 167 static int bgpio_get(struct gpio_chip *gc, unsigned int gpio) 168 { 169 return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio)); 170 } 171 172 /* 173 * This only works if the bits in the GPIO register are in native endianness. 174 */ 175 static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask, 176 unsigned long *bits) 177 { 178 /* Make sure we first clear any bits that are zero when we read the register */ 179 *bits &= ~*mask; 180 *bits |= gc->read_reg(gc->reg_dat) & *mask; 181 return 0; 182 } 183 184 /* 185 * With big endian mirrored bit order it becomes more tedious. 186 */ 187 static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask, 188 unsigned long *bits) 189 { 190 unsigned long readmask = 0; 191 unsigned long val; 192 int bit; 193 194 /* Make sure we first clear any bits that are zero when we read the register */ 195 *bits &= ~*mask; 196 197 /* Create a mirrored mask */ 198 for_each_set_bit(bit, mask, gc->ngpio) 199 readmask |= bgpio_line2mask(gc, bit); 200 201 /* Read the register */ 202 val = gc->read_reg(gc->reg_dat) & readmask; 203 204 /* 205 * Mirror the result into the "bits" result, this will give line 0 206 * in bit 0 ... line 31 in bit 31 for a 32bit register. 207 */ 208 for_each_set_bit(bit, &val, gc->ngpio) 209 *bits |= bgpio_line2mask(gc, bit); 210 211 return 0; 212 } 213 214 static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val) 215 { 216 } 217 218 static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) 219 { 220 unsigned long mask = bgpio_line2mask(gc, gpio); 221 unsigned long flags; 222 223 spin_lock_irqsave(&gc->bgpio_lock, flags); 224 225 if (val) 226 gc->bgpio_data |= mask; 227 else 228 gc->bgpio_data &= ~mask; 229 230 gc->write_reg(gc->reg_dat, gc->bgpio_data); 231 232 spin_unlock_irqrestore(&gc->bgpio_lock, flags); 233 } 234 235 static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, 236 int val) 237 { 238 unsigned long mask = bgpio_line2mask(gc, gpio); 239 240 if (val) 241 gc->write_reg(gc->reg_set, mask); 242 else 243 gc->write_reg(gc->reg_clr, mask); 244 } 245 246 static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val) 247 { 248 unsigned long mask = bgpio_line2mask(gc, gpio); 249 unsigned long flags; 250 251 spin_lock_irqsave(&gc->bgpio_lock, flags); 252 253 if (val) 254 gc->bgpio_data |= mask; 255 else 256 gc->bgpio_data &= ~mask; 257 258 gc->write_reg(gc->reg_set, gc->bgpio_data); 259 260 spin_unlock_irqrestore(&gc->bgpio_lock, flags); 261 } 262 263 static void bgpio_multiple_get_masks(struct gpio_chip *gc, 264 unsigned long *mask, unsigned long *bits, 265 unsigned long *set_mask, 266 unsigned long *clear_mask) 267 { 268 int i; 269 270 *set_mask = 0; 271 *clear_mask = 0; 272 273 for_each_set_bit(i, mask, gc->bgpio_bits) { 274 if (test_bit(i, bits)) 275 *set_mask |= bgpio_line2mask(gc, i); 276 else 277 *clear_mask |= bgpio_line2mask(gc, i); 278 } 279 } 280 281 static void bgpio_set_multiple_single_reg(struct gpio_chip *gc, 282 unsigned long *mask, 283 unsigned long *bits, 284 void __iomem *reg) 285 { 286 unsigned long flags; 287 unsigned long set_mask, clear_mask; 288 289 spin_lock_irqsave(&gc->bgpio_lock, flags); 290 291 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask); 292 293 gc->bgpio_data |= set_mask; 294 gc->bgpio_data &= ~clear_mask; 295 296 gc->write_reg(reg, gc->bgpio_data); 297 298 spin_unlock_irqrestore(&gc->bgpio_lock, flags); 299 } 300 301 static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, 302 unsigned long *bits) 303 { 304 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_dat); 305 } 306 307 static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask, 308 unsigned long *bits) 309 { 310 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_set); 311 } 312 313 static void bgpio_set_multiple_with_clear(struct gpio_chip *gc, 314 unsigned long *mask, 315 unsigned long *bits) 316 { 317 unsigned long set_mask, clear_mask; 318 319 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask); 320 321 if (set_mask) 322 gc->write_reg(gc->reg_set, set_mask); 323 if (clear_mask) 324 gc->write_reg(gc->reg_clr, clear_mask); 325 } 326 327 static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio) 328 { 329 return 0; 330 } 331 332 static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio, 333 int val) 334 { 335 return -EINVAL; 336 } 337 338 static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio, 339 int val) 340 { 341 gc->set(gc, gpio, val); 342 343 return 0; 344 } 345 346 static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) 347 { 348 unsigned long flags; 349 350 spin_lock_irqsave(&gc->bgpio_lock, flags); 351 352 gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); 353 354 if (gc->reg_dir_in) 355 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); 356 if (gc->reg_dir_out) 357 gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); 358 359 spin_unlock_irqrestore(&gc->bgpio_lock, flags); 360 361 return 0; 362 } 363 364 static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio) 365 { 366 /* Return 0 if output, 1 if input */ 367 if (gc->bgpio_dir_unreadable) { 368 if (gc->bgpio_dir & bgpio_line2mask(gc, gpio)) 369 return GPIO_LINE_DIRECTION_OUT; 370 return GPIO_LINE_DIRECTION_IN; 371 } 372 373 if (gc->reg_dir_out) { 374 if (gc->read_reg(gc->reg_dir_out) & bgpio_line2mask(gc, gpio)) 375 return GPIO_LINE_DIRECTION_OUT; 376 return GPIO_LINE_DIRECTION_IN; 377 } 378 379 if (gc->reg_dir_in) 380 if (!(gc->read_reg(gc->reg_dir_in) & bgpio_line2mask(gc, gpio))) 381 return GPIO_LINE_DIRECTION_OUT; 382 383 return GPIO_LINE_DIRECTION_IN; 384 } 385 386 static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) 387 { 388 unsigned long flags; 389 390 spin_lock_irqsave(&gc->bgpio_lock, flags); 391 392 gc->bgpio_dir |= bgpio_line2mask(gc, gpio); 393 394 if (gc->reg_dir_in) 395 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); 396 if (gc->reg_dir_out) 397 gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); 398 399 spin_unlock_irqrestore(&gc->bgpio_lock, flags); 400 } 401 402 static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio, 403 int val) 404 { 405 bgpio_dir_out(gc, gpio, val); 406 gc->set(gc, gpio, val); 407 return 0; 408 } 409 410 static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio, 411 int val) 412 { 413 gc->set(gc, gpio, val); 414 bgpio_dir_out(gc, gpio, val); 415 return 0; 416 } 417 418 static int bgpio_setup_accessors(struct device *dev, 419 struct gpio_chip *gc, 420 bool byte_be) 421 { 422 423 switch (gc->bgpio_bits) { 424 case 8: 425 gc->read_reg = bgpio_read8; 426 gc->write_reg = bgpio_write8; 427 break; 428 case 16: 429 if (byte_be) { 430 gc->read_reg = bgpio_read16be; 431 gc->write_reg = bgpio_write16be; 432 } else { 433 gc->read_reg = bgpio_read16; 434 gc->write_reg = bgpio_write16; 435 } 436 break; 437 case 32: 438 if (byte_be) { 439 gc->read_reg = bgpio_read32be; 440 gc->write_reg = bgpio_write32be; 441 } else { 442 gc->read_reg = bgpio_read32; 443 gc->write_reg = bgpio_write32; 444 } 445 break; 446 #if BITS_PER_LONG >= 64 447 case 64: 448 if (byte_be) { 449 dev_err(dev, 450 "64 bit big endian byte order unsupported\n"); 451 return -EINVAL; 452 } else { 453 gc->read_reg = bgpio_read64; 454 gc->write_reg = bgpio_write64; 455 } 456 break; 457 #endif /* BITS_PER_LONG >= 64 */ 458 default: 459 dev_err(dev, "unsupported data width %u bits\n", gc->bgpio_bits); 460 return -EINVAL; 461 } 462 463 return 0; 464 } 465 466 /* 467 * Create the device and allocate the resources. For setting GPIO's there are 468 * three supported configurations: 469 * 470 * - single input/output register resource (named "dat"). 471 * - set/clear pair (named "set" and "clr"). 472 * - single output register resource and single input resource ("set" and 473 * dat"). 474 * 475 * For the single output register, this drives a 1 by setting a bit and a zero 476 * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit 477 * in the set register and clears it by setting a bit in the clear register. 478 * The configuration is detected by which resources are present. 479 * 480 * For setting the GPIO direction, there are three supported configurations: 481 * 482 * - simple bidirection GPIO that requires no configuration. 483 * - an output direction register (named "dirout") where a 1 bit 484 * indicates the GPIO is an output. 485 * - an input direction register (named "dirin") where a 1 bit indicates 486 * the GPIO is an input. 487 */ 488 static int bgpio_setup_io(struct gpio_chip *gc, 489 void __iomem *dat, 490 void __iomem *set, 491 void __iomem *clr, 492 unsigned long flags) 493 { 494 495 gc->reg_dat = dat; 496 if (!gc->reg_dat) 497 return -EINVAL; 498 499 if (set && clr) { 500 gc->reg_set = set; 501 gc->reg_clr = clr; 502 gc->set = bgpio_set_with_clear; 503 gc->set_multiple = bgpio_set_multiple_with_clear; 504 } else if (set && !clr) { 505 gc->reg_set = set; 506 gc->set = bgpio_set_set; 507 gc->set_multiple = bgpio_set_multiple_set; 508 } else if (flags & BGPIOF_NO_OUTPUT) { 509 gc->set = bgpio_set_none; 510 gc->set_multiple = NULL; 511 } else { 512 gc->set = bgpio_set; 513 gc->set_multiple = bgpio_set_multiple; 514 } 515 516 if (!(flags & BGPIOF_UNREADABLE_REG_SET) && 517 (flags & BGPIOF_READ_OUTPUT_REG_SET)) { 518 gc->get = bgpio_get_set; 519 if (!gc->be_bits) 520 gc->get_multiple = bgpio_get_set_multiple; 521 /* 522 * We deliberately avoid assigning the ->get_multiple() call 523 * for big endian mirrored registers which are ALSO reflecting 524 * their value in the set register when used as output. It is 525 * simply too much complexity, let the GPIO core fall back to 526 * reading each line individually in that fringe case. 527 */ 528 } else { 529 gc->get = bgpio_get; 530 if (gc->be_bits) 531 gc->get_multiple = bgpio_get_multiple_be; 532 else 533 gc->get_multiple = bgpio_get_multiple; 534 } 535 536 return 0; 537 } 538 539 static int bgpio_setup_direction(struct gpio_chip *gc, 540 void __iomem *dirout, 541 void __iomem *dirin, 542 unsigned long flags) 543 { 544 if (dirout || dirin) { 545 gc->reg_dir_out = dirout; 546 gc->reg_dir_in = dirin; 547 if (flags & BGPIOF_NO_SET_ON_INPUT) 548 gc->direction_output = bgpio_dir_out_dir_first; 549 else 550 gc->direction_output = bgpio_dir_out_val_first; 551 gc->direction_input = bgpio_dir_in; 552 gc->get_direction = bgpio_get_dir; 553 } else { 554 if (flags & BGPIOF_NO_OUTPUT) 555 gc->direction_output = bgpio_dir_out_err; 556 else 557 gc->direction_output = bgpio_simple_dir_out; 558 gc->direction_input = bgpio_simple_dir_in; 559 } 560 561 return 0; 562 } 563 564 static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin) 565 { 566 if (gpio_pin < chip->ngpio) 567 return 0; 568 569 return -EINVAL; 570 } 571 572 /** 573 * bgpio_init() - Initialize generic GPIO accessor functions 574 * @gc: the GPIO chip to set up 575 * @dev: the parent device of the new GPIO chip (compulsory) 576 * @sz: the size (width) of the MMIO registers in bytes, typically 1, 2 or 4 577 * @dat: MMIO address for the register to READ the value of the GPIO lines, it 578 * is expected that a 1 in the corresponding bit in this register means the 579 * line is asserted 580 * @set: MMIO address for the register to SET the value of the GPIO lines, it is 581 * expected that we write the line with 1 in this register to drive the GPIO line 582 * high. 583 * @clr: MMIO address for the register to CLEAR the value of the GPIO lines, it is 584 * expected that we write the line with 1 in this register to drive the GPIO line 585 * low. It is allowed to leave this address as NULL, in that case the SET register 586 * will be assumed to also clear the GPIO lines, by actively writing the line 587 * with 0. 588 * @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed 589 * that setting a line to 1 in this register will turn that line into an 590 * output line. Conversely, setting the line to 0 will turn that line into 591 * an input. 592 * @dirin: MMIO address for the register to set this line as INPUT. It is assumed 593 * that setting a line to 1 in this register will turn that line into an 594 * input line. Conversely, setting the line to 0 will turn that line into 595 * an output. 596 * @flags: Different flags that will affect the behaviour of the device, such as 597 * endianness etc. 598 */ 599 int bgpio_init(struct gpio_chip *gc, struct device *dev, 600 unsigned long sz, void __iomem *dat, void __iomem *set, 601 void __iomem *clr, void __iomem *dirout, void __iomem *dirin, 602 unsigned long flags) 603 { 604 int ret; 605 606 if (!is_power_of_2(sz)) 607 return -EINVAL; 608 609 gc->bgpio_bits = sz * 8; 610 if (gc->bgpio_bits > BITS_PER_LONG) 611 return -EINVAL; 612 613 spin_lock_init(&gc->bgpio_lock); 614 gc->parent = dev; 615 gc->label = dev_name(dev); 616 gc->base = -1; 617 gc->ngpio = gc->bgpio_bits; 618 gc->request = bgpio_request; 619 gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN); 620 621 ret = bgpio_setup_io(gc, dat, set, clr, flags); 622 if (ret) 623 return ret; 624 625 ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER); 626 if (ret) 627 return ret; 628 629 ret = bgpio_setup_direction(gc, dirout, dirin, flags); 630 if (ret) 631 return ret; 632 633 gc->bgpio_data = gc->read_reg(gc->reg_dat); 634 if (gc->set == bgpio_set_set && 635 !(flags & BGPIOF_UNREADABLE_REG_SET)) 636 gc->bgpio_data = gc->read_reg(gc->reg_set); 637 638 if (flags & BGPIOF_UNREADABLE_REG_DIR) 639 gc->bgpio_dir_unreadable = true; 640 641 /* 642 * Inspect hardware to find initial direction setting. 643 */ 644 if ((gc->reg_dir_out || gc->reg_dir_in) && 645 !(flags & BGPIOF_UNREADABLE_REG_DIR)) { 646 if (gc->reg_dir_out) 647 gc->bgpio_dir = gc->read_reg(gc->reg_dir_out); 648 else if (gc->reg_dir_in) 649 gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in); 650 /* 651 * If we have two direction registers, synchronise 652 * input setting to output setting, the library 653 * can not handle a line being input and output at 654 * the same time. 655 */ 656 if (gc->reg_dir_out && gc->reg_dir_in) 657 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); 658 } 659 660 return ret; 661 } 662 EXPORT_SYMBOL_GPL(bgpio_init); 663 664 #if IS_ENABLED(CONFIG_GPIO_GENERIC_PLATFORM) 665 666 static void __iomem *bgpio_map(struct platform_device *pdev, 667 const char *name, 668 resource_size_t sane_sz) 669 { 670 struct resource *r; 671 resource_size_t sz; 672 673 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name); 674 if (!r) 675 return NULL; 676 677 sz = resource_size(r); 678 if (sz != sane_sz) 679 return IOMEM_ERR_PTR(-EINVAL); 680 681 return devm_ioremap_resource(&pdev->dev, r); 682 } 683 684 #ifdef CONFIG_OF 685 static const struct of_device_id bgpio_of_match[] = { 686 { .compatible = "brcm,bcm6345-gpio" }, 687 { .compatible = "wd,mbl-gpio" }, 688 { .compatible = "ni,169445-nand-gpio" }, 689 { } 690 }; 691 MODULE_DEVICE_TABLE(of, bgpio_of_match); 692 693 static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, 694 unsigned long *flags) 695 { 696 struct bgpio_pdata *pdata; 697 698 if (!of_match_device(bgpio_of_match, &pdev->dev)) 699 return NULL; 700 701 pdata = devm_kzalloc(&pdev->dev, sizeof(struct bgpio_pdata), 702 GFP_KERNEL); 703 if (!pdata) 704 return ERR_PTR(-ENOMEM); 705 706 pdata->base = -1; 707 708 if (of_device_is_big_endian(pdev->dev.of_node)) 709 *flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER; 710 711 if (of_property_read_bool(pdev->dev.of_node, "no-output")) 712 *flags |= BGPIOF_NO_OUTPUT; 713 714 return pdata; 715 } 716 #else 717 static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev, 718 unsigned long *flags) 719 { 720 return NULL; 721 } 722 #endif /* CONFIG_OF */ 723 724 static int bgpio_pdev_probe(struct platform_device *pdev) 725 { 726 struct device *dev = &pdev->dev; 727 struct resource *r; 728 void __iomem *dat; 729 void __iomem *set; 730 void __iomem *clr; 731 void __iomem *dirout; 732 void __iomem *dirin; 733 unsigned long sz; 734 unsigned long flags = 0; 735 int err; 736 struct gpio_chip *gc; 737 struct bgpio_pdata *pdata; 738 739 pdata = bgpio_parse_dt(pdev, &flags); 740 if (IS_ERR(pdata)) 741 return PTR_ERR(pdata); 742 743 if (!pdata) { 744 pdata = dev_get_platdata(dev); 745 flags = pdev->id_entry->driver_data; 746 } 747 748 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat"); 749 if (!r) 750 return -EINVAL; 751 752 sz = resource_size(r); 753 754 dat = bgpio_map(pdev, "dat", sz); 755 if (IS_ERR(dat)) 756 return PTR_ERR(dat); 757 758 set = bgpio_map(pdev, "set", sz); 759 if (IS_ERR(set)) 760 return PTR_ERR(set); 761 762 clr = bgpio_map(pdev, "clr", sz); 763 if (IS_ERR(clr)) 764 return PTR_ERR(clr); 765 766 dirout = bgpio_map(pdev, "dirout", sz); 767 if (IS_ERR(dirout)) 768 return PTR_ERR(dirout); 769 770 dirin = bgpio_map(pdev, "dirin", sz); 771 if (IS_ERR(dirin)) 772 return PTR_ERR(dirin); 773 774 gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL); 775 if (!gc) 776 return -ENOMEM; 777 778 err = bgpio_init(gc, dev, sz, dat, set, clr, dirout, dirin, flags); 779 if (err) 780 return err; 781 782 if (pdata) { 783 if (pdata->label) 784 gc->label = pdata->label; 785 gc->base = pdata->base; 786 if (pdata->ngpio > 0) 787 gc->ngpio = pdata->ngpio; 788 } 789 790 platform_set_drvdata(pdev, gc); 791 792 return devm_gpiochip_add_data(&pdev->dev, gc, NULL); 793 } 794 795 static const struct platform_device_id bgpio_id_table[] = { 796 { 797 .name = "basic-mmio-gpio", 798 .driver_data = 0, 799 }, { 800 .name = "basic-mmio-gpio-be", 801 .driver_data = BGPIOF_BIG_ENDIAN, 802 }, 803 { } 804 }; 805 MODULE_DEVICE_TABLE(platform, bgpio_id_table); 806 807 static struct platform_driver bgpio_driver = { 808 .driver = { 809 .name = "basic-mmio-gpio", 810 .of_match_table = of_match_ptr(bgpio_of_match), 811 }, 812 .id_table = bgpio_id_table, 813 .probe = bgpio_pdev_probe, 814 }; 815 816 module_platform_driver(bgpio_driver); 817 818 #endif /* CONFIG_GPIO_GENERIC_PLATFORM */ 819 820 MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers"); 821 MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>"); 822 MODULE_LICENSE("GPL"); 823