1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * TI DaVinci GPIO Support 4 * 5 * Copyright (c) 2006-2007 David Brownell 6 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com> 7 */ 8 9 #include <linux/gpio/driver.h> 10 #include <linux/errno.h> 11 #include <linux/kernel.h> 12 #include <linux/clk.h> 13 #include <linux/err.h> 14 #include <linux/io.h> 15 #include <linux/irq.h> 16 #include <linux/irqdomain.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/of_device.h> 20 #include <linux/pinctrl/consumer.h> 21 #include <linux/platform_device.h> 22 #include <linux/platform_data/gpio-davinci.h> 23 #include <linux/irqchip/chained_irq.h> 24 #include <linux/spinlock.h> 25 26 #include <asm-generic/gpio.h> 27 28 #define MAX_REGS_BANKS 5 29 #define MAX_INT_PER_BANK 32 30 31 struct davinci_gpio_regs { 32 u32 dir; 33 u32 out_data; 34 u32 set_data; 35 u32 clr_data; 36 u32 in_data; 37 u32 set_rising; 38 u32 clr_rising; 39 u32 set_falling; 40 u32 clr_falling; 41 u32 intstat; 42 }; 43 44 typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq); 45 46 #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */ 47 48 static void __iomem *gpio_base; 49 static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0}; 50 51 struct davinci_gpio_irq_data { 52 void __iomem *regs; 53 struct davinci_gpio_controller *chip; 54 int bank_num; 55 }; 56 57 struct davinci_gpio_controller { 58 struct gpio_chip chip; 59 struct irq_domain *irq_domain; 60 /* Serialize access to GPIO registers */ 61 spinlock_t lock; 62 void __iomem *regs[MAX_REGS_BANKS]; 63 int gpio_unbanked; 64 int irqs[MAX_INT_PER_BANK]; 65 }; 66 67 static inline u32 __gpio_mask(unsigned gpio) 68 { 69 return 1 << (gpio % 32); 70 } 71 72 static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d) 73 { 74 struct davinci_gpio_regs __iomem *g; 75 76 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d); 77 78 return g; 79 } 80 81 static int davinci_gpio_irq_setup(struct platform_device *pdev); 82 83 /*--------------------------------------------------------------------------*/ 84 85 /* board setup code *MUST* setup pinmux and enable the GPIO clock. */ 86 static inline int __davinci_direction(struct gpio_chip *chip, 87 unsigned offset, bool out, int value) 88 { 89 struct davinci_gpio_controller *d = gpiochip_get_data(chip); 90 struct davinci_gpio_regs __iomem *g; 91 unsigned long flags; 92 u32 temp; 93 int bank = offset / 32; 94 u32 mask = __gpio_mask(offset); 95 96 g = d->regs[bank]; 97 spin_lock_irqsave(&d->lock, flags); 98 temp = readl_relaxed(&g->dir); 99 if (out) { 100 temp &= ~mask; 101 writel_relaxed(mask, value ? &g->set_data : &g->clr_data); 102 } else { 103 temp |= mask; 104 } 105 writel_relaxed(temp, &g->dir); 106 spin_unlock_irqrestore(&d->lock, flags); 107 108 return 0; 109 } 110 111 static int davinci_direction_in(struct gpio_chip *chip, unsigned offset) 112 { 113 return __davinci_direction(chip, offset, false, 0); 114 } 115 116 static int 117 davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value) 118 { 119 return __davinci_direction(chip, offset, true, value); 120 } 121 122 /* 123 * Read the pin's value (works even if it's set up as output); 124 * returns zero/nonzero. 125 * 126 * Note that changes are synched to the GPIO clock, so reading values back 127 * right after you've set them may give old values. 128 */ 129 static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset) 130 { 131 struct davinci_gpio_controller *d = gpiochip_get_data(chip); 132 struct davinci_gpio_regs __iomem *g; 133 int bank = offset / 32; 134 135 g = d->regs[bank]; 136 137 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data)); 138 } 139 140 /* 141 * Assuming the pin is muxed as a gpio output, set its output value. 142 */ 143 static void 144 davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value) 145 { 146 struct davinci_gpio_controller *d = gpiochip_get_data(chip); 147 struct davinci_gpio_regs __iomem *g; 148 int bank = offset / 32; 149 150 g = d->regs[bank]; 151 152 writel_relaxed(__gpio_mask(offset), 153 value ? &g->set_data : &g->clr_data); 154 } 155 156 static struct davinci_gpio_platform_data * 157 davinci_gpio_get_pdata(struct platform_device *pdev) 158 { 159 struct device_node *dn = pdev->dev.of_node; 160 struct davinci_gpio_platform_data *pdata; 161 int ret; 162 u32 val; 163 164 if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node) 165 return dev_get_platdata(&pdev->dev); 166 167 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); 168 if (!pdata) 169 return NULL; 170 171 ret = of_property_read_u32(dn, "ti,ngpio", &val); 172 if (ret) 173 goto of_err; 174 175 pdata->ngpio = val; 176 177 ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val); 178 if (ret) 179 goto of_err; 180 181 pdata->gpio_unbanked = val; 182 183 return pdata; 184 185 of_err: 186 dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret); 187 return NULL; 188 } 189 190 static int davinci_gpio_probe(struct platform_device *pdev) 191 { 192 int bank, i, ret = 0; 193 unsigned int ngpio, nbank, nirq; 194 struct davinci_gpio_controller *chips; 195 struct davinci_gpio_platform_data *pdata; 196 struct device *dev = &pdev->dev; 197 198 pdata = davinci_gpio_get_pdata(pdev); 199 if (!pdata) { 200 dev_err(dev, "No platform data found\n"); 201 return -EINVAL; 202 } 203 204 dev->platform_data = pdata; 205 206 /* 207 * The gpio banks conceptually expose a segmented bitmap, 208 * and "ngpio" is one more than the largest zero-based 209 * bit index that's valid. 210 */ 211 ngpio = pdata->ngpio; 212 if (ngpio == 0) { 213 dev_err(dev, "How many GPIOs?\n"); 214 return -EINVAL; 215 } 216 217 if (WARN_ON(ARCH_NR_GPIOS < ngpio)) 218 ngpio = ARCH_NR_GPIOS; 219 220 /* 221 * If there are unbanked interrupts then the number of 222 * interrupts is equal to number of gpios else all are banked so 223 * number of interrupts is equal to number of banks(each with 16 gpios) 224 */ 225 if (pdata->gpio_unbanked) 226 nirq = pdata->gpio_unbanked; 227 else 228 nirq = DIV_ROUND_UP(ngpio, 16); 229 230 chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL); 231 if (!chips) 232 return -ENOMEM; 233 234 gpio_base = devm_platform_ioremap_resource(pdev, 0); 235 if (IS_ERR(gpio_base)) 236 return PTR_ERR(gpio_base); 237 238 for (i = 0; i < nirq; i++) { 239 chips->irqs[i] = platform_get_irq(pdev, i); 240 if (chips->irqs[i] < 0) 241 return dev_err_probe(dev, chips->irqs[i], "IRQ not populated\n"); 242 } 243 244 chips->chip.label = dev_name(dev); 245 246 chips->chip.direction_input = davinci_direction_in; 247 chips->chip.get = davinci_gpio_get; 248 chips->chip.direction_output = davinci_direction_out; 249 chips->chip.set = davinci_gpio_set; 250 251 chips->chip.ngpio = ngpio; 252 chips->chip.base = pdata->no_auto_base ? pdata->base : -1; 253 254 #ifdef CONFIG_OF_GPIO 255 chips->chip.of_gpio_n_cells = 2; 256 chips->chip.parent = dev; 257 chips->chip.request = gpiochip_generic_request; 258 chips->chip.free = gpiochip_generic_free; 259 #endif 260 spin_lock_init(&chips->lock); 261 262 nbank = DIV_ROUND_UP(ngpio, 32); 263 for (bank = 0; bank < nbank; bank++) 264 chips->regs[bank] = gpio_base + offset_array[bank]; 265 266 ret = devm_gpiochip_add_data(dev, &chips->chip, chips); 267 if (ret) 268 return ret; 269 270 platform_set_drvdata(pdev, chips); 271 ret = davinci_gpio_irq_setup(pdev); 272 if (ret) 273 return ret; 274 275 return 0; 276 } 277 278 /*--------------------------------------------------------------------------*/ 279 /* 280 * We expect irqs will normally be set up as input pins, but they can also be 281 * used as output pins ... which is convenient for testing. 282 * 283 * NOTE: The first few GPIOs also have direct INTC hookups in addition 284 * to their GPIOBNK0 irq, with a bit less overhead. 285 * 286 * All those INTC hookups (direct, plus several IRQ banks) can also 287 * serve as EDMA event triggers. 288 */ 289 290 static void gpio_irq_disable(struct irq_data *d) 291 { 292 struct davinci_gpio_regs __iomem *g = irq2regs(d); 293 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d); 294 295 writel_relaxed(mask, &g->clr_falling); 296 writel_relaxed(mask, &g->clr_rising); 297 } 298 299 static void gpio_irq_enable(struct irq_data *d) 300 { 301 struct davinci_gpio_regs __iomem *g = irq2regs(d); 302 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d); 303 unsigned status = irqd_get_trigger_type(d); 304 305 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING; 306 if (!status) 307 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING; 308 309 if (status & IRQ_TYPE_EDGE_FALLING) 310 writel_relaxed(mask, &g->set_falling); 311 if (status & IRQ_TYPE_EDGE_RISING) 312 writel_relaxed(mask, &g->set_rising); 313 } 314 315 static int gpio_irq_type(struct irq_data *d, unsigned trigger) 316 { 317 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) 318 return -EINVAL; 319 320 return 0; 321 } 322 323 static struct irq_chip gpio_irqchip = { 324 .name = "GPIO", 325 .irq_enable = gpio_irq_enable, 326 .irq_disable = gpio_irq_disable, 327 .irq_set_type = gpio_irq_type, 328 .flags = IRQCHIP_SET_TYPE_MASKED, 329 }; 330 331 static void gpio_irq_handler(struct irq_desc *desc) 332 { 333 struct davinci_gpio_regs __iomem *g; 334 u32 mask = 0xffff; 335 int bank_num; 336 struct davinci_gpio_controller *d; 337 struct davinci_gpio_irq_data *irqdata; 338 339 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc); 340 bank_num = irqdata->bank_num; 341 g = irqdata->regs; 342 d = irqdata->chip; 343 344 /* we only care about one bank */ 345 if ((bank_num % 2) == 1) 346 mask <<= 16; 347 348 /* temporarily mask (level sensitive) parent IRQ */ 349 chained_irq_enter(irq_desc_get_chip(desc), desc); 350 while (1) { 351 u32 status; 352 int bit; 353 irq_hw_number_t hw_irq; 354 355 /* ack any irqs */ 356 status = readl_relaxed(&g->intstat) & mask; 357 if (!status) 358 break; 359 writel_relaxed(status, &g->intstat); 360 361 /* now demux them to the right lowlevel handler */ 362 363 while (status) { 364 bit = __ffs(status); 365 status &= ~BIT(bit); 366 /* Max number of gpios per controller is 144 so 367 * hw_irq will be in [0..143] 368 */ 369 hw_irq = (bank_num / 2) * 32 + bit; 370 371 generic_handle_domain_irq(d->irq_domain, hw_irq); 372 } 373 } 374 chained_irq_exit(irq_desc_get_chip(desc), desc); 375 /* now it may re-trigger */ 376 } 377 378 static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset) 379 { 380 struct davinci_gpio_controller *d = gpiochip_get_data(chip); 381 382 if (d->irq_domain) 383 return irq_create_mapping(d->irq_domain, offset); 384 else 385 return -ENXIO; 386 } 387 388 static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset) 389 { 390 struct davinci_gpio_controller *d = gpiochip_get_data(chip); 391 392 /* 393 * NOTE: we assume for now that only irqs in the first gpio_chip 394 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs). 395 */ 396 if (offset < d->gpio_unbanked) 397 return d->irqs[offset]; 398 else 399 return -ENODEV; 400 } 401 402 static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger) 403 { 404 struct davinci_gpio_controller *d; 405 struct davinci_gpio_regs __iomem *g; 406 u32 mask, i; 407 408 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data); 409 g = (struct davinci_gpio_regs __iomem *)d->regs[0]; 410 for (i = 0; i < MAX_INT_PER_BANK; i++) 411 if (data->irq == d->irqs[i]) 412 break; 413 414 if (i == MAX_INT_PER_BANK) 415 return -EINVAL; 416 417 mask = __gpio_mask(i); 418 419 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)) 420 return -EINVAL; 421 422 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING) 423 ? &g->set_falling : &g->clr_falling); 424 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING) 425 ? &g->set_rising : &g->clr_rising); 426 427 return 0; 428 } 429 430 static int 431 davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq, 432 irq_hw_number_t hw) 433 { 434 struct davinci_gpio_controller *chips = 435 (struct davinci_gpio_controller *)d->host_data; 436 struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32]; 437 438 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq, 439 "davinci_gpio"); 440 irq_set_irq_type(irq, IRQ_TYPE_NONE); 441 irq_set_chip_data(irq, (__force void *)g); 442 irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw)); 443 444 return 0; 445 } 446 447 static const struct irq_domain_ops davinci_gpio_irq_ops = { 448 .map = davinci_gpio_irq_map, 449 .xlate = irq_domain_xlate_onetwocell, 450 }; 451 452 static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq) 453 { 454 static struct irq_chip_type gpio_unbanked; 455 456 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq)); 457 458 return &gpio_unbanked.chip; 459 }; 460 461 static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq) 462 { 463 static struct irq_chip gpio_unbanked; 464 465 gpio_unbanked = *irq_get_chip(irq); 466 return &gpio_unbanked; 467 }; 468 469 static const struct of_device_id davinci_gpio_ids[]; 470 471 /* 472 * NOTE: for suspend/resume, probably best to make a platform_device with 473 * suspend_late/resume_resume calls hooking into results of the set_wake() 474 * calls ... so if no gpios are wakeup events the clock can be disabled, 475 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0 476 * (dm6446) can be set appropriately for GPIOV33 pins. 477 */ 478 479 static int davinci_gpio_irq_setup(struct platform_device *pdev) 480 { 481 unsigned gpio, bank; 482 int irq; 483 int ret; 484 struct clk *clk; 485 u32 binten = 0; 486 unsigned ngpio; 487 struct device *dev = &pdev->dev; 488 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev); 489 struct davinci_gpio_platform_data *pdata = dev->platform_data; 490 struct davinci_gpio_regs __iomem *g; 491 struct irq_domain *irq_domain = NULL; 492 const struct of_device_id *match; 493 struct irq_chip *irq_chip; 494 struct davinci_gpio_irq_data *irqdata; 495 gpio_get_irq_chip_cb_t gpio_get_irq_chip; 496 497 /* 498 * Use davinci_gpio_get_irq_chip by default to handle non DT cases 499 */ 500 gpio_get_irq_chip = davinci_gpio_get_irq_chip; 501 match = of_match_device(of_match_ptr(davinci_gpio_ids), 502 dev); 503 if (match) 504 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)match->data; 505 506 ngpio = pdata->ngpio; 507 508 clk = devm_clk_get(dev, "gpio"); 509 if (IS_ERR(clk)) { 510 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk)); 511 return PTR_ERR(clk); 512 } 513 514 ret = clk_prepare_enable(clk); 515 if (ret) 516 return ret; 517 518 if (!pdata->gpio_unbanked) { 519 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0); 520 if (irq < 0) { 521 dev_err(dev, "Couldn't allocate IRQ numbers\n"); 522 clk_disable_unprepare(clk); 523 return irq; 524 } 525 526 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0, 527 &davinci_gpio_irq_ops, 528 chips); 529 if (!irq_domain) { 530 dev_err(dev, "Couldn't register an IRQ domain\n"); 531 clk_disable_unprepare(clk); 532 return -ENODEV; 533 } 534 } 535 536 /* 537 * Arrange gpio_to_irq() support, handling either direct IRQs or 538 * banked IRQs. Having GPIOs in the first GPIO bank use direct 539 * IRQs, while the others use banked IRQs, would need some setup 540 * tweaks to recognize hardware which can do that. 541 */ 542 chips->chip.to_irq = gpio_to_irq_banked; 543 chips->irq_domain = irq_domain; 544 545 /* 546 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO 547 * controller only handling trigger modes. We currently assume no 548 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs. 549 */ 550 if (pdata->gpio_unbanked) { 551 /* pass "bank 0" GPIO IRQs to AINTC */ 552 chips->chip.to_irq = gpio_to_irq_unbanked; 553 chips->gpio_unbanked = pdata->gpio_unbanked; 554 binten = GENMASK(pdata->gpio_unbanked / 16, 0); 555 556 /* AINTC handles mask/unmask; GPIO handles triggering */ 557 irq = chips->irqs[0]; 558 irq_chip = gpio_get_irq_chip(irq); 559 irq_chip->name = "GPIO-AINTC"; 560 irq_chip->irq_set_type = gpio_irq_type_unbanked; 561 562 /* default trigger: both edges */ 563 g = chips->regs[0]; 564 writel_relaxed(~0, &g->set_falling); 565 writel_relaxed(~0, &g->set_rising); 566 567 /* set the direct IRQs up to use that irqchip */ 568 for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++) { 569 irq_set_chip(chips->irqs[gpio], irq_chip); 570 irq_set_handler_data(chips->irqs[gpio], chips); 571 irq_set_status_flags(chips->irqs[gpio], 572 IRQ_TYPE_EDGE_BOTH); 573 } 574 575 goto done; 576 } 577 578 /* 579 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we 580 * then chain through our own handler. 581 */ 582 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) { 583 /* disabled by default, enabled only as needed 584 * There are register sets for 32 GPIOs. 2 banks of 16 585 * GPIOs are covered by each set of registers hence divide by 2 586 */ 587 g = chips->regs[bank / 2]; 588 writel_relaxed(~0, &g->clr_falling); 589 writel_relaxed(~0, &g->clr_rising); 590 591 /* 592 * Each chip handles 32 gpios, and each irq bank consists of 16 593 * gpio irqs. Pass the irq bank's corresponding controller to 594 * the chained irq handler. 595 */ 596 irqdata = devm_kzalloc(&pdev->dev, 597 sizeof(struct 598 davinci_gpio_irq_data), 599 GFP_KERNEL); 600 if (!irqdata) { 601 clk_disable_unprepare(clk); 602 return -ENOMEM; 603 } 604 605 irqdata->regs = g; 606 irqdata->bank_num = bank; 607 irqdata->chip = chips; 608 609 irq_set_chained_handler_and_data(chips->irqs[bank], 610 gpio_irq_handler, irqdata); 611 612 binten |= BIT(bank); 613 } 614 615 done: 616 /* 617 * BINTEN -- per-bank interrupt enable. genirq would also let these 618 * bits be set/cleared dynamically. 619 */ 620 writel_relaxed(binten, gpio_base + BINTEN); 621 622 return 0; 623 } 624 625 static const struct of_device_id davinci_gpio_ids[] = { 626 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip}, 627 { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip}, 628 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip}, 629 { /* sentinel */ }, 630 }; 631 MODULE_DEVICE_TABLE(of, davinci_gpio_ids); 632 633 static struct platform_driver davinci_gpio_driver = { 634 .probe = davinci_gpio_probe, 635 .driver = { 636 .name = "davinci_gpio", 637 .of_match_table = of_match_ptr(davinci_gpio_ids), 638 }, 639 }; 640 641 /** 642 * GPIO driver registration needs to be done before machine_init functions 643 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall. 644 */ 645 static int __init davinci_gpio_drv_reg(void) 646 { 647 return platform_driver_register(&davinci_gpio_driver); 648 } 649 postcore_initcall(davinci_gpio_drv_reg); 650