1 /* 2 * Emma Mobile GPIO Support - GIO 3 * 4 * Copyright (C) 2012 Magnus Damm 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #include <linux/init.h> 21 #include <linux/platform_device.h> 22 #include <linux/spinlock.h> 23 #include <linux/interrupt.h> 24 #include <linux/ioport.h> 25 #include <linux/io.h> 26 #include <linux/irq.h> 27 #include <linux/irqdomain.h> 28 #include <linux/bitops.h> 29 #include <linux/err.h> 30 #include <linux/gpio.h> 31 #include <linux/slab.h> 32 #include <linux/module.h> 33 #include <linux/pinctrl/consumer.h> 34 35 struct em_gio_priv { 36 void __iomem *base0; 37 void __iomem *base1; 38 spinlock_t sense_lock; 39 struct platform_device *pdev; 40 struct gpio_chip gpio_chip; 41 struct irq_chip irq_chip; 42 struct irq_domain *irq_domain; 43 }; 44 45 #define GIO_E1 0x00 46 #define GIO_E0 0x04 47 #define GIO_EM 0x04 48 #define GIO_OL 0x08 49 #define GIO_OH 0x0c 50 #define GIO_I 0x10 51 #define GIO_IIA 0x14 52 #define GIO_IEN 0x18 53 #define GIO_IDS 0x1c 54 #define GIO_IIM 0x1c 55 #define GIO_RAW 0x20 56 #define GIO_MST 0x24 57 #define GIO_IIR 0x28 58 59 #define GIO_IDT0 0x40 60 #define GIO_IDT1 0x44 61 #define GIO_IDT2 0x48 62 #define GIO_IDT3 0x4c 63 #define GIO_RAWBL 0x50 64 #define GIO_RAWBH 0x54 65 #define GIO_IRBL 0x58 66 #define GIO_IRBH 0x5c 67 68 #define GIO_IDT(n) (GIO_IDT0 + ((n) * 4)) 69 70 static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs) 71 { 72 if (offs < GIO_IDT0) 73 return ioread32(p->base0 + offs); 74 else 75 return ioread32(p->base1 + (offs - GIO_IDT0)); 76 } 77 78 static inline void em_gio_write(struct em_gio_priv *p, int offs, 79 unsigned long value) 80 { 81 if (offs < GIO_IDT0) 82 iowrite32(value, p->base0 + offs); 83 else 84 iowrite32(value, p->base1 + (offs - GIO_IDT0)); 85 } 86 87 static void em_gio_irq_disable(struct irq_data *d) 88 { 89 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 90 91 em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d))); 92 } 93 94 static void em_gio_irq_enable(struct irq_data *d) 95 { 96 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 97 98 em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d))); 99 } 100 101 static int em_gio_irq_reqres(struct irq_data *d) 102 { 103 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 104 105 if (gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d))) { 106 dev_err(p->gpio_chip.parent, 107 "unable to lock HW IRQ %lu for IRQ\n", 108 irqd_to_hwirq(d)); 109 return -EINVAL; 110 } 111 return 0; 112 } 113 114 static void em_gio_irq_relres(struct irq_data *d) 115 { 116 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 117 118 gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); 119 } 120 121 122 #define GIO_ASYNC(x) (x + 8) 123 124 static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = { 125 [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00), 126 [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01), 127 [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02), 128 [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03), 129 [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04), 130 }; 131 132 static int em_gio_irq_set_type(struct irq_data *d, unsigned int type) 133 { 134 unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK]; 135 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 136 unsigned int reg, offset, shift; 137 unsigned long flags; 138 unsigned long tmp; 139 140 if (!value) 141 return -EINVAL; 142 143 offset = irqd_to_hwirq(d); 144 145 pr_debug("gio: sense irq = %d, mode = %d\n", offset, value); 146 147 /* 8 x 4 bit fields in 4 IDT registers */ 148 reg = GIO_IDT(offset >> 3); 149 shift = (offset & 0x07) << 4; 150 151 spin_lock_irqsave(&p->sense_lock, flags); 152 153 /* disable the interrupt in IIA */ 154 tmp = em_gio_read(p, GIO_IIA); 155 tmp &= ~BIT(offset); 156 em_gio_write(p, GIO_IIA, tmp); 157 158 /* change the sense setting in IDT */ 159 tmp = em_gio_read(p, reg); 160 tmp &= ~(0xf << shift); 161 tmp |= value << shift; 162 em_gio_write(p, reg, tmp); 163 164 /* clear pending interrupts */ 165 em_gio_write(p, GIO_IIR, BIT(offset)); 166 167 /* enable the interrupt in IIA */ 168 tmp = em_gio_read(p, GIO_IIA); 169 tmp |= BIT(offset); 170 em_gio_write(p, GIO_IIA, tmp); 171 172 spin_unlock_irqrestore(&p->sense_lock, flags); 173 174 return 0; 175 } 176 177 static irqreturn_t em_gio_irq_handler(int irq, void *dev_id) 178 { 179 struct em_gio_priv *p = dev_id; 180 unsigned long pending; 181 unsigned int offset, irqs_handled = 0; 182 183 while ((pending = em_gio_read(p, GIO_MST))) { 184 offset = __ffs(pending); 185 em_gio_write(p, GIO_IIR, BIT(offset)); 186 generic_handle_irq(irq_find_mapping(p->irq_domain, offset)); 187 irqs_handled++; 188 } 189 190 return irqs_handled ? IRQ_HANDLED : IRQ_NONE; 191 } 192 193 static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip) 194 { 195 return gpiochip_get_data(chip); 196 } 197 198 static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset) 199 { 200 em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset)); 201 return 0; 202 } 203 204 static int em_gio_get(struct gpio_chip *chip, unsigned offset) 205 { 206 return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset)); 207 } 208 209 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg, 210 unsigned shift, int value) 211 { 212 /* upper 16 bits contains mask and lower 16 actual value */ 213 em_gio_write(gpio_to_priv(chip), reg, 214 (BIT(shift + 16)) | (value << shift)); 215 } 216 217 static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value) 218 { 219 /* output is split into two registers */ 220 if (offset < 16) 221 __em_gio_set(chip, GIO_OL, offset, value); 222 else 223 __em_gio_set(chip, GIO_OH, offset - 16, value); 224 } 225 226 static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset, 227 int value) 228 { 229 /* write GPIO value to output before selecting output mode of pin */ 230 em_gio_set(chip, offset, value); 231 em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset)); 232 return 0; 233 } 234 235 static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset) 236 { 237 return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); 238 } 239 240 static int em_gio_request(struct gpio_chip *chip, unsigned offset) 241 { 242 return pinctrl_request_gpio(chip->base + offset); 243 } 244 245 static void em_gio_free(struct gpio_chip *chip, unsigned offset) 246 { 247 pinctrl_free_gpio(chip->base + offset); 248 249 /* Set the GPIO as an input to ensure that the next GPIO request won't 250 * drive the GPIO pin as an output. 251 */ 252 em_gio_direction_input(chip, offset); 253 } 254 255 static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq, 256 irq_hw_number_t hwirq) 257 { 258 struct em_gio_priv *p = h->host_data; 259 260 pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq); 261 262 irq_set_chip_data(irq, h->host_data); 263 irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq); 264 return 0; 265 } 266 267 static const struct irq_domain_ops em_gio_irq_domain_ops = { 268 .map = em_gio_irq_domain_map, 269 .xlate = irq_domain_xlate_twocell, 270 }; 271 272 static int em_gio_probe(struct platform_device *pdev) 273 { 274 struct em_gio_priv *p; 275 struct resource *io[2], *irq[2]; 276 struct gpio_chip *gpio_chip; 277 struct irq_chip *irq_chip; 278 const char *name = dev_name(&pdev->dev); 279 unsigned int ngpios; 280 int ret; 281 282 p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL); 283 if (!p) { 284 ret = -ENOMEM; 285 goto err0; 286 } 287 288 p->pdev = pdev; 289 platform_set_drvdata(pdev, p); 290 spin_lock_init(&p->sense_lock); 291 292 io[0] = platform_get_resource(pdev, IORESOURCE_MEM, 0); 293 io[1] = platform_get_resource(pdev, IORESOURCE_MEM, 1); 294 irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0); 295 irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1); 296 297 if (!io[0] || !io[1] || !irq[0] || !irq[1]) { 298 dev_err(&pdev->dev, "missing IRQ or IOMEM\n"); 299 ret = -EINVAL; 300 goto err0; 301 } 302 303 p->base0 = devm_ioremap_nocache(&pdev->dev, io[0]->start, 304 resource_size(io[0])); 305 if (!p->base0) { 306 dev_err(&pdev->dev, "failed to remap low I/O memory\n"); 307 ret = -ENXIO; 308 goto err0; 309 } 310 311 p->base1 = devm_ioremap_nocache(&pdev->dev, io[1]->start, 312 resource_size(io[1])); 313 if (!p->base1) { 314 dev_err(&pdev->dev, "failed to remap high I/O memory\n"); 315 ret = -ENXIO; 316 goto err0; 317 } 318 319 if (of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios)) { 320 dev_err(&pdev->dev, "Missing ngpios OF property\n"); 321 ret = -EINVAL; 322 goto err0; 323 } 324 325 gpio_chip = &p->gpio_chip; 326 gpio_chip->of_node = pdev->dev.of_node; 327 gpio_chip->direction_input = em_gio_direction_input; 328 gpio_chip->get = em_gio_get; 329 gpio_chip->direction_output = em_gio_direction_output; 330 gpio_chip->set = em_gio_set; 331 gpio_chip->to_irq = em_gio_to_irq; 332 gpio_chip->request = em_gio_request; 333 gpio_chip->free = em_gio_free; 334 gpio_chip->label = name; 335 gpio_chip->parent = &pdev->dev; 336 gpio_chip->owner = THIS_MODULE; 337 gpio_chip->base = -1; 338 gpio_chip->ngpio = ngpios; 339 340 irq_chip = &p->irq_chip; 341 irq_chip->name = name; 342 irq_chip->irq_mask = em_gio_irq_disable; 343 irq_chip->irq_unmask = em_gio_irq_enable; 344 irq_chip->irq_set_type = em_gio_irq_set_type; 345 irq_chip->irq_request_resources = em_gio_irq_reqres; 346 irq_chip->irq_release_resources = em_gio_irq_relres; 347 irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND; 348 349 p->irq_domain = irq_domain_add_simple(pdev->dev.of_node, ngpios, 0, 350 &em_gio_irq_domain_ops, p); 351 if (!p->irq_domain) { 352 ret = -ENXIO; 353 dev_err(&pdev->dev, "cannot initialize irq domain\n"); 354 goto err0; 355 } 356 357 if (devm_request_irq(&pdev->dev, irq[0]->start, 358 em_gio_irq_handler, 0, name, p)) { 359 dev_err(&pdev->dev, "failed to request low IRQ\n"); 360 ret = -ENOENT; 361 goto err1; 362 } 363 364 if (devm_request_irq(&pdev->dev, irq[1]->start, 365 em_gio_irq_handler, 0, name, p)) { 366 dev_err(&pdev->dev, "failed to request high IRQ\n"); 367 ret = -ENOENT; 368 goto err1; 369 } 370 371 ret = gpiochip_add_data(gpio_chip, p); 372 if (ret) { 373 dev_err(&pdev->dev, "failed to add GPIO controller\n"); 374 goto err1; 375 } 376 377 return 0; 378 379 err1: 380 irq_domain_remove(p->irq_domain); 381 err0: 382 return ret; 383 } 384 385 static int em_gio_remove(struct platform_device *pdev) 386 { 387 struct em_gio_priv *p = platform_get_drvdata(pdev); 388 389 gpiochip_remove(&p->gpio_chip); 390 391 irq_domain_remove(p->irq_domain); 392 return 0; 393 } 394 395 static const struct of_device_id em_gio_dt_ids[] = { 396 { .compatible = "renesas,em-gio", }, 397 {}, 398 }; 399 MODULE_DEVICE_TABLE(of, em_gio_dt_ids); 400 401 static struct platform_driver em_gio_device_driver = { 402 .probe = em_gio_probe, 403 .remove = em_gio_remove, 404 .driver = { 405 .name = "em_gio", 406 .of_match_table = em_gio_dt_ids, 407 } 408 }; 409 410 static int __init em_gio_init(void) 411 { 412 return platform_driver_register(&em_gio_device_driver); 413 } 414 postcore_initcall(em_gio_init); 415 416 static void __exit em_gio_exit(void) 417 { 418 platform_driver_unregister(&em_gio_device_driver); 419 } 420 module_exit(em_gio_exit); 421 422 MODULE_AUTHOR("Magnus Damm"); 423 MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver"); 424 MODULE_LICENSE("GPL v2"); 425