1 /* 2 * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> 3 * Copyright 2008 Juergen Beisert, kernel@pengutronix.de 4 * 5 * Based on code from Freescale, 6 * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 2 11 * of the License, or (at your option) any later version. 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 20 */ 21 22 #include <linux/init.h> 23 #include <linux/interrupt.h> 24 #include <linux/io.h> 25 #include <linux/irq.h> 26 #include <linux/irqdomain.h> 27 #include <linux/irqchip/chained_irq.h> 28 #include <linux/gpio.h> 29 #include <linux/platform_device.h> 30 #include <linux/slab.h> 31 #include <linux/basic_mmio_gpio.h> 32 #include <linux/of.h> 33 #include <linux/of_device.h> 34 #include <linux/module.h> 35 #include <asm-generic/bug.h> 36 37 enum mxc_gpio_hwtype { 38 IMX1_GPIO, /* runs on i.mx1 */ 39 IMX21_GPIO, /* runs on i.mx21 and i.mx27 */ 40 IMX31_GPIO, /* runs on i.mx31 */ 41 IMX35_GPIO, /* runs on all other i.mx */ 42 }; 43 44 /* device type dependent stuff */ 45 struct mxc_gpio_hwdata { 46 unsigned dr_reg; 47 unsigned gdir_reg; 48 unsigned psr_reg; 49 unsigned icr1_reg; 50 unsigned icr2_reg; 51 unsigned imr_reg; 52 unsigned isr_reg; 53 int edge_sel_reg; 54 unsigned low_level; 55 unsigned high_level; 56 unsigned rise_edge; 57 unsigned fall_edge; 58 }; 59 60 struct mxc_gpio_port { 61 struct list_head node; 62 void __iomem *base; 63 int irq; 64 int irq_high; 65 struct irq_domain *domain; 66 struct bgpio_chip bgc; 67 u32 both_edges; 68 }; 69 70 static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = { 71 .dr_reg = 0x1c, 72 .gdir_reg = 0x00, 73 .psr_reg = 0x24, 74 .icr1_reg = 0x28, 75 .icr2_reg = 0x2c, 76 .imr_reg = 0x30, 77 .isr_reg = 0x34, 78 .edge_sel_reg = -EINVAL, 79 .low_level = 0x03, 80 .high_level = 0x02, 81 .rise_edge = 0x00, 82 .fall_edge = 0x01, 83 }; 84 85 static struct mxc_gpio_hwdata imx31_gpio_hwdata = { 86 .dr_reg = 0x00, 87 .gdir_reg = 0x04, 88 .psr_reg = 0x08, 89 .icr1_reg = 0x0c, 90 .icr2_reg = 0x10, 91 .imr_reg = 0x14, 92 .isr_reg = 0x18, 93 .edge_sel_reg = -EINVAL, 94 .low_level = 0x00, 95 .high_level = 0x01, 96 .rise_edge = 0x02, 97 .fall_edge = 0x03, 98 }; 99 100 static struct mxc_gpio_hwdata imx35_gpio_hwdata = { 101 .dr_reg = 0x00, 102 .gdir_reg = 0x04, 103 .psr_reg = 0x08, 104 .icr1_reg = 0x0c, 105 .icr2_reg = 0x10, 106 .imr_reg = 0x14, 107 .isr_reg = 0x18, 108 .edge_sel_reg = 0x1c, 109 .low_level = 0x00, 110 .high_level = 0x01, 111 .rise_edge = 0x02, 112 .fall_edge = 0x03, 113 }; 114 115 static enum mxc_gpio_hwtype mxc_gpio_hwtype; 116 static struct mxc_gpio_hwdata *mxc_gpio_hwdata; 117 118 #define GPIO_DR (mxc_gpio_hwdata->dr_reg) 119 #define GPIO_GDIR (mxc_gpio_hwdata->gdir_reg) 120 #define GPIO_PSR (mxc_gpio_hwdata->psr_reg) 121 #define GPIO_ICR1 (mxc_gpio_hwdata->icr1_reg) 122 #define GPIO_ICR2 (mxc_gpio_hwdata->icr2_reg) 123 #define GPIO_IMR (mxc_gpio_hwdata->imr_reg) 124 #define GPIO_ISR (mxc_gpio_hwdata->isr_reg) 125 #define GPIO_EDGE_SEL (mxc_gpio_hwdata->edge_sel_reg) 126 127 #define GPIO_INT_LOW_LEV (mxc_gpio_hwdata->low_level) 128 #define GPIO_INT_HIGH_LEV (mxc_gpio_hwdata->high_level) 129 #define GPIO_INT_RISE_EDGE (mxc_gpio_hwdata->rise_edge) 130 #define GPIO_INT_FALL_EDGE (mxc_gpio_hwdata->fall_edge) 131 #define GPIO_INT_BOTH_EDGES 0x4 132 133 static struct platform_device_id mxc_gpio_devtype[] = { 134 { 135 .name = "imx1-gpio", 136 .driver_data = IMX1_GPIO, 137 }, { 138 .name = "imx21-gpio", 139 .driver_data = IMX21_GPIO, 140 }, { 141 .name = "imx31-gpio", 142 .driver_data = IMX31_GPIO, 143 }, { 144 .name = "imx35-gpio", 145 .driver_data = IMX35_GPIO, 146 }, { 147 /* sentinel */ 148 } 149 }; 150 151 static const struct of_device_id mxc_gpio_dt_ids[] = { 152 { .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], }, 153 { .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], }, 154 { .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], }, 155 { .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], }, 156 { /* sentinel */ } 157 }; 158 159 /* 160 * MX2 has one interrupt *for all* gpio ports. The list is used 161 * to save the references to all ports, so that mx2_gpio_irq_handler 162 * can walk through all interrupt status registers. 163 */ 164 static LIST_HEAD(mxc_gpio_ports); 165 166 /* Note: This driver assumes 32 GPIOs are handled in one register */ 167 168 static int gpio_set_irq_type(struct irq_data *d, u32 type) 169 { 170 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); 171 struct mxc_gpio_port *port = gc->private; 172 u32 bit, val; 173 u32 gpio_idx = d->hwirq; 174 u32 gpio = port->bgc.gc.base + gpio_idx; 175 int edge; 176 void __iomem *reg = port->base; 177 178 port->both_edges &= ~(1 << gpio_idx); 179 switch (type) { 180 case IRQ_TYPE_EDGE_RISING: 181 edge = GPIO_INT_RISE_EDGE; 182 break; 183 case IRQ_TYPE_EDGE_FALLING: 184 edge = GPIO_INT_FALL_EDGE; 185 break; 186 case IRQ_TYPE_EDGE_BOTH: 187 if (GPIO_EDGE_SEL >= 0) { 188 edge = GPIO_INT_BOTH_EDGES; 189 } else { 190 val = gpio_get_value(gpio); 191 if (val) { 192 edge = GPIO_INT_LOW_LEV; 193 pr_debug("mxc: set GPIO %d to low trigger\n", gpio); 194 } else { 195 edge = GPIO_INT_HIGH_LEV; 196 pr_debug("mxc: set GPIO %d to high trigger\n", gpio); 197 } 198 port->both_edges |= 1 << gpio_idx; 199 } 200 break; 201 case IRQ_TYPE_LEVEL_LOW: 202 edge = GPIO_INT_LOW_LEV; 203 break; 204 case IRQ_TYPE_LEVEL_HIGH: 205 edge = GPIO_INT_HIGH_LEV; 206 break; 207 default: 208 return -EINVAL; 209 } 210 211 if (GPIO_EDGE_SEL >= 0) { 212 val = readl(port->base + GPIO_EDGE_SEL); 213 if (edge == GPIO_INT_BOTH_EDGES) 214 writel(val | (1 << gpio_idx), 215 port->base + GPIO_EDGE_SEL); 216 else 217 writel(val & ~(1 << gpio_idx), 218 port->base + GPIO_EDGE_SEL); 219 } 220 221 if (edge != GPIO_INT_BOTH_EDGES) { 222 reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */ 223 bit = gpio_idx & 0xf; 224 val = readl(reg) & ~(0x3 << (bit << 1)); 225 writel(val | (edge << (bit << 1)), reg); 226 } 227 228 writel(1 << gpio_idx, port->base + GPIO_ISR); 229 230 return 0; 231 } 232 233 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) 234 { 235 void __iomem *reg = port->base; 236 u32 bit, val; 237 int edge; 238 239 reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ 240 bit = gpio & 0xf; 241 val = readl(reg); 242 edge = (val >> (bit << 1)) & 3; 243 val &= ~(0x3 << (bit << 1)); 244 if (edge == GPIO_INT_HIGH_LEV) { 245 edge = GPIO_INT_LOW_LEV; 246 pr_debug("mxc: switch GPIO %d to low trigger\n", gpio); 247 } else if (edge == GPIO_INT_LOW_LEV) { 248 edge = GPIO_INT_HIGH_LEV; 249 pr_debug("mxc: switch GPIO %d to high trigger\n", gpio); 250 } else { 251 pr_err("mxc: invalid configuration for GPIO %d: %x\n", 252 gpio, edge); 253 return; 254 } 255 writel(val | (edge << (bit << 1)), reg); 256 } 257 258 /* handle 32 interrupts in one status register */ 259 static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat) 260 { 261 while (irq_stat != 0) { 262 int irqoffset = fls(irq_stat) - 1; 263 264 if (port->both_edges & (1 << irqoffset)) 265 mxc_flip_edge(port, irqoffset); 266 267 generic_handle_irq(irq_find_mapping(port->domain, irqoffset)); 268 269 irq_stat &= ~(1 << irqoffset); 270 } 271 } 272 273 /* MX1 and MX3 has one interrupt *per* gpio port */ 274 static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc) 275 { 276 u32 irq_stat; 277 struct mxc_gpio_port *port = irq_get_handler_data(irq); 278 struct irq_chip *chip = irq_get_chip(irq); 279 280 chained_irq_enter(chip, desc); 281 282 irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR); 283 284 mxc_gpio_irq_handler(port, irq_stat); 285 286 chained_irq_exit(chip, desc); 287 } 288 289 /* MX2 has one interrupt *for all* gpio ports */ 290 static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc) 291 { 292 u32 irq_msk, irq_stat; 293 struct mxc_gpio_port *port; 294 295 /* walk through all interrupt status registers */ 296 list_for_each_entry(port, &mxc_gpio_ports, node) { 297 irq_msk = readl(port->base + GPIO_IMR); 298 if (!irq_msk) 299 continue; 300 301 irq_stat = readl(port->base + GPIO_ISR) & irq_msk; 302 if (irq_stat) 303 mxc_gpio_irq_handler(port, irq_stat); 304 } 305 } 306 307 /* 308 * Set interrupt number "irq" in the GPIO as a wake-up source. 309 * While system is running, all registered GPIO interrupts need to have 310 * wake-up enabled. When system is suspended, only selected GPIO interrupts 311 * need to have wake-up enabled. 312 * @param irq interrupt source number 313 * @param enable enable as wake-up if equal to non-zero 314 * @return This function returns 0 on success. 315 */ 316 static int gpio_set_wake_irq(struct irq_data *d, u32 enable) 317 { 318 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); 319 struct mxc_gpio_port *port = gc->private; 320 u32 gpio_idx = d->hwirq; 321 322 if (enable) { 323 if (port->irq_high && (gpio_idx >= 16)) 324 enable_irq_wake(port->irq_high); 325 else 326 enable_irq_wake(port->irq); 327 } else { 328 if (port->irq_high && (gpio_idx >= 16)) 329 disable_irq_wake(port->irq_high); 330 else 331 disable_irq_wake(port->irq); 332 } 333 334 return 0; 335 } 336 337 static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base) 338 { 339 struct irq_chip_generic *gc; 340 struct irq_chip_type *ct; 341 342 gc = irq_alloc_generic_chip("gpio-mxc", 1, irq_base, 343 port->base, handle_level_irq); 344 gc->private = port; 345 346 ct = gc->chip_types; 347 ct->chip.irq_ack = irq_gc_ack_set_bit; 348 ct->chip.irq_mask = irq_gc_mask_clr_bit; 349 ct->chip.irq_unmask = irq_gc_mask_set_bit; 350 ct->chip.irq_set_type = gpio_set_irq_type; 351 ct->chip.irq_set_wake = gpio_set_wake_irq; 352 ct->regs.ack = GPIO_ISR; 353 ct->regs.mask = GPIO_IMR; 354 355 irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK, 356 IRQ_NOREQUEST, 0); 357 } 358 359 static void mxc_gpio_get_hw(struct platform_device *pdev) 360 { 361 const struct of_device_id *of_id = 362 of_match_device(mxc_gpio_dt_ids, &pdev->dev); 363 enum mxc_gpio_hwtype hwtype; 364 365 if (of_id) 366 pdev->id_entry = of_id->data; 367 hwtype = pdev->id_entry->driver_data; 368 369 if (mxc_gpio_hwtype) { 370 /* 371 * The driver works with a reasonable presupposition, 372 * that is all gpio ports must be the same type when 373 * running on one soc. 374 */ 375 BUG_ON(mxc_gpio_hwtype != hwtype); 376 return; 377 } 378 379 if (hwtype == IMX35_GPIO) 380 mxc_gpio_hwdata = &imx35_gpio_hwdata; 381 else if (hwtype == IMX31_GPIO) 382 mxc_gpio_hwdata = &imx31_gpio_hwdata; 383 else 384 mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata; 385 386 mxc_gpio_hwtype = hwtype; 387 } 388 389 static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset) 390 { 391 struct bgpio_chip *bgc = to_bgpio_chip(gc); 392 struct mxc_gpio_port *port = 393 container_of(bgc, struct mxc_gpio_port, bgc); 394 395 return irq_find_mapping(port->domain, offset); 396 } 397 398 static int mxc_gpio_probe(struct platform_device *pdev) 399 { 400 struct device_node *np = pdev->dev.of_node; 401 struct mxc_gpio_port *port; 402 struct resource *iores; 403 int irq_base; 404 int err; 405 406 mxc_gpio_get_hw(pdev); 407 408 port = kzalloc(sizeof(struct mxc_gpio_port), GFP_KERNEL); 409 if (!port) 410 return -ENOMEM; 411 412 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); 413 if (!iores) { 414 err = -ENODEV; 415 goto out_kfree; 416 } 417 418 if (!request_mem_region(iores->start, resource_size(iores), 419 pdev->name)) { 420 err = -EBUSY; 421 goto out_kfree; 422 } 423 424 port->base = ioremap(iores->start, resource_size(iores)); 425 if (!port->base) { 426 err = -ENOMEM; 427 goto out_release_mem; 428 } 429 430 port->irq_high = platform_get_irq(pdev, 1); 431 port->irq = platform_get_irq(pdev, 0); 432 if (port->irq < 0) { 433 err = -EINVAL; 434 goto out_iounmap; 435 } 436 437 /* disable the interrupt and clear the status */ 438 writel(0, port->base + GPIO_IMR); 439 writel(~0, port->base + GPIO_ISR); 440 441 if (mxc_gpio_hwtype == IMX21_GPIO) { 442 /* 443 * Setup one handler for all GPIO interrupts. Actually setting 444 * the handler is needed only once, but doing it for every port 445 * is more robust and easier. 446 */ 447 irq_set_chained_handler(port->irq, mx2_gpio_irq_handler); 448 } else { 449 /* setup one handler for each entry */ 450 irq_set_chained_handler(port->irq, mx3_gpio_irq_handler); 451 irq_set_handler_data(port->irq, port); 452 if (port->irq_high > 0) { 453 /* setup handler for GPIO 16 to 31 */ 454 irq_set_chained_handler(port->irq_high, 455 mx3_gpio_irq_handler); 456 irq_set_handler_data(port->irq_high, port); 457 } 458 } 459 460 err = bgpio_init(&port->bgc, &pdev->dev, 4, 461 port->base + GPIO_PSR, 462 port->base + GPIO_DR, NULL, 463 port->base + GPIO_GDIR, NULL, 0); 464 if (err) 465 goto out_iounmap; 466 467 port->bgc.gc.to_irq = mxc_gpio_to_irq; 468 port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 : 469 pdev->id * 32; 470 471 err = gpiochip_add(&port->bgc.gc); 472 if (err) 473 goto out_bgpio_remove; 474 475 irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id()); 476 if (irq_base < 0) { 477 err = irq_base; 478 goto out_gpiochip_remove; 479 } 480 481 port->domain = irq_domain_add_legacy(np, 32, irq_base, 0, 482 &irq_domain_simple_ops, NULL); 483 if (!port->domain) { 484 err = -ENODEV; 485 goto out_irqdesc_free; 486 } 487 488 /* gpio-mxc can be a generic irq chip */ 489 mxc_gpio_init_gc(port, irq_base); 490 491 list_add_tail(&port->node, &mxc_gpio_ports); 492 493 return 0; 494 495 out_irqdesc_free: 496 irq_free_descs(irq_base, 32); 497 out_gpiochip_remove: 498 WARN_ON(gpiochip_remove(&port->bgc.gc) < 0); 499 out_bgpio_remove: 500 bgpio_remove(&port->bgc); 501 out_iounmap: 502 iounmap(port->base); 503 out_release_mem: 504 release_mem_region(iores->start, resource_size(iores)); 505 out_kfree: 506 kfree(port); 507 dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err); 508 return err; 509 } 510 511 static struct platform_driver mxc_gpio_driver = { 512 .driver = { 513 .name = "gpio-mxc", 514 .owner = THIS_MODULE, 515 .of_match_table = mxc_gpio_dt_ids, 516 }, 517 .probe = mxc_gpio_probe, 518 .id_table = mxc_gpio_devtype, 519 }; 520 521 static int __init gpio_mxc_init(void) 522 { 523 return platform_driver_register(&mxc_gpio_driver); 524 } 525 postcore_initcall(gpio_mxc_init); 526 527 MODULE_AUTHOR("Freescale Semiconductor, " 528 "Daniel Mack <danielncaiaq.de>, " 529 "Juergen Beisert <kernel@pengutronix.de>"); 530 MODULE_DESCRIPTION("Freescale MXC GPIO"); 531 MODULE_LICENSE("GPL"); 532