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