1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Emma Mobile GPIO Support - GIO 4 * 5 * Copyright (C) 2012 Magnus Damm 6 */ 7 8 #include <linux/init.h> 9 #include <linux/platform_device.h> 10 #include <linux/spinlock.h> 11 #include <linux/interrupt.h> 12 #include <linux/ioport.h> 13 #include <linux/io.h> 14 #include <linux/irq.h> 15 #include <linux/irqdomain.h> 16 #include <linux/bitops.h> 17 #include <linux/err.h> 18 #include <linux/gpio/driver.h> 19 #include <linux/slab.h> 20 #include <linux/module.h> 21 #include <linux/pinctrl/consumer.h> 22 23 struct em_gio_priv { 24 void __iomem *base0; 25 void __iomem *base1; 26 spinlock_t sense_lock; 27 struct platform_device *pdev; 28 struct gpio_chip gpio_chip; 29 struct irq_chip irq_chip; 30 struct irq_domain *irq_domain; 31 }; 32 33 #define GIO_E1 0x00 34 #define GIO_E0 0x04 35 #define GIO_EM 0x04 36 #define GIO_OL 0x08 37 #define GIO_OH 0x0c 38 #define GIO_I 0x10 39 #define GIO_IIA 0x14 40 #define GIO_IEN 0x18 41 #define GIO_IDS 0x1c 42 #define GIO_IIM 0x1c 43 #define GIO_RAW 0x20 44 #define GIO_MST 0x24 45 #define GIO_IIR 0x28 46 47 #define GIO_IDT0 0x40 48 #define GIO_IDT1 0x44 49 #define GIO_IDT2 0x48 50 #define GIO_IDT3 0x4c 51 #define GIO_RAWBL 0x50 52 #define GIO_RAWBH 0x54 53 #define GIO_IRBL 0x58 54 #define GIO_IRBH 0x5c 55 56 #define GIO_IDT(n) (GIO_IDT0 + ((n) * 4)) 57 58 static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs) 59 { 60 if (offs < GIO_IDT0) 61 return ioread32(p->base0 + offs); 62 else 63 return ioread32(p->base1 + (offs - GIO_IDT0)); 64 } 65 66 static inline void em_gio_write(struct em_gio_priv *p, int offs, 67 unsigned long value) 68 { 69 if (offs < GIO_IDT0) 70 iowrite32(value, p->base0 + offs); 71 else 72 iowrite32(value, p->base1 + (offs - GIO_IDT0)); 73 } 74 75 static void em_gio_irq_disable(struct irq_data *d) 76 { 77 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 78 79 em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d))); 80 } 81 82 static void em_gio_irq_enable(struct irq_data *d) 83 { 84 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 85 86 em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d))); 87 } 88 89 static int em_gio_irq_reqres(struct irq_data *d) 90 { 91 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 92 int ret; 93 94 ret = gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); 95 if (ret) { 96 dev_err(p->gpio_chip.parent, 97 "unable to lock HW IRQ %lu for IRQ\n", 98 irqd_to_hwirq(d)); 99 return ret; 100 } 101 return 0; 102 } 103 104 static void em_gio_irq_relres(struct irq_data *d) 105 { 106 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 107 108 gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d)); 109 } 110 111 112 #define GIO_ASYNC(x) (x + 8) 113 114 static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = { 115 [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00), 116 [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01), 117 [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02), 118 [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03), 119 [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04), 120 }; 121 122 static int em_gio_irq_set_type(struct irq_data *d, unsigned int type) 123 { 124 unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK]; 125 struct em_gio_priv *p = irq_data_get_irq_chip_data(d); 126 unsigned int reg, offset, shift; 127 unsigned long flags; 128 unsigned long tmp; 129 130 if (!value) 131 return -EINVAL; 132 133 offset = irqd_to_hwirq(d); 134 135 pr_debug("gio: sense irq = %d, mode = %d\n", offset, value); 136 137 /* 8 x 4 bit fields in 4 IDT registers */ 138 reg = GIO_IDT(offset >> 3); 139 shift = (offset & 0x07) << 4; 140 141 spin_lock_irqsave(&p->sense_lock, flags); 142 143 /* disable the interrupt in IIA */ 144 tmp = em_gio_read(p, GIO_IIA); 145 tmp &= ~BIT(offset); 146 em_gio_write(p, GIO_IIA, tmp); 147 148 /* change the sense setting in IDT */ 149 tmp = em_gio_read(p, reg); 150 tmp &= ~(0xf << shift); 151 tmp |= value << shift; 152 em_gio_write(p, reg, tmp); 153 154 /* clear pending interrupts */ 155 em_gio_write(p, GIO_IIR, BIT(offset)); 156 157 /* enable the interrupt in IIA */ 158 tmp = em_gio_read(p, GIO_IIA); 159 tmp |= BIT(offset); 160 em_gio_write(p, GIO_IIA, tmp); 161 162 spin_unlock_irqrestore(&p->sense_lock, flags); 163 164 return 0; 165 } 166 167 static irqreturn_t em_gio_irq_handler(int irq, void *dev_id) 168 { 169 struct em_gio_priv *p = dev_id; 170 unsigned long pending; 171 unsigned int offset, irqs_handled = 0; 172 173 while ((pending = em_gio_read(p, GIO_MST))) { 174 offset = __ffs(pending); 175 em_gio_write(p, GIO_IIR, BIT(offset)); 176 generic_handle_domain_irq(p->irq_domain, offset); 177 irqs_handled++; 178 } 179 180 return irqs_handled ? IRQ_HANDLED : IRQ_NONE; 181 } 182 183 static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip) 184 { 185 return gpiochip_get_data(chip); 186 } 187 188 static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset) 189 { 190 em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset)); 191 return 0; 192 } 193 194 static int em_gio_get(struct gpio_chip *chip, unsigned offset) 195 { 196 return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset)); 197 } 198 199 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg, 200 unsigned shift, int value) 201 { 202 /* upper 16 bits contains mask and lower 16 actual value */ 203 em_gio_write(gpio_to_priv(chip), reg, 204 (BIT(shift + 16)) | (value << shift)); 205 } 206 207 static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value) 208 { 209 /* output is split into two registers */ 210 if (offset < 16) 211 __em_gio_set(chip, GIO_OL, offset, value); 212 else 213 __em_gio_set(chip, GIO_OH, offset - 16, value); 214 } 215 216 static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset, 217 int value) 218 { 219 /* write GPIO value to output before selecting output mode of pin */ 220 em_gio_set(chip, offset, value); 221 em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset)); 222 return 0; 223 } 224 225 static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset) 226 { 227 return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset); 228 } 229 230 static int em_gio_request(struct gpio_chip *chip, unsigned offset) 231 { 232 return pinctrl_gpio_request(chip->base + offset); 233 } 234 235 static void em_gio_free(struct gpio_chip *chip, unsigned offset) 236 { 237 pinctrl_gpio_free(chip->base + offset); 238 239 /* Set the GPIO as an input to ensure that the next GPIO request won't 240 * drive the GPIO pin as an output. 241 */ 242 em_gio_direction_input(chip, offset); 243 } 244 245 static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq, 246 irq_hw_number_t hwirq) 247 { 248 struct em_gio_priv *p = h->host_data; 249 250 pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq); 251 252 irq_set_chip_data(irq, h->host_data); 253 irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq); 254 return 0; 255 } 256 257 static const struct irq_domain_ops em_gio_irq_domain_ops = { 258 .map = em_gio_irq_domain_map, 259 .xlate = irq_domain_xlate_twocell, 260 }; 261 262 static void em_gio_irq_domain_remove(void *data) 263 { 264 struct irq_domain *domain = data; 265 266 irq_domain_remove(domain); 267 } 268 269 static int em_gio_probe(struct platform_device *pdev) 270 { 271 struct em_gio_priv *p; 272 struct gpio_chip *gpio_chip; 273 struct irq_chip *irq_chip; 274 struct device *dev = &pdev->dev; 275 const char *name = dev_name(dev); 276 unsigned int ngpios; 277 int irq[2], ret; 278 279 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 280 if (!p) 281 return -ENOMEM; 282 283 p->pdev = pdev; 284 platform_set_drvdata(pdev, p); 285 spin_lock_init(&p->sense_lock); 286 287 irq[0] = platform_get_irq(pdev, 0); 288 if (irq[0] < 0) 289 return irq[0]; 290 291 irq[1] = platform_get_irq(pdev, 1); 292 if (irq[1] < 0) 293 return irq[1]; 294 295 p->base0 = devm_platform_ioremap_resource(pdev, 0); 296 if (IS_ERR(p->base0)) 297 return PTR_ERR(p->base0); 298 299 p->base1 = devm_platform_ioremap_resource(pdev, 1); 300 if (IS_ERR(p->base1)) 301 return PTR_ERR(p->base1); 302 303 if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) { 304 dev_err(dev, "Missing ngpios OF property\n"); 305 return -EINVAL; 306 } 307 308 gpio_chip = &p->gpio_chip; 309 gpio_chip->direction_input = em_gio_direction_input; 310 gpio_chip->get = em_gio_get; 311 gpio_chip->direction_output = em_gio_direction_output; 312 gpio_chip->set = em_gio_set; 313 gpio_chip->to_irq = em_gio_to_irq; 314 gpio_chip->request = em_gio_request; 315 gpio_chip->free = em_gio_free; 316 gpio_chip->label = name; 317 gpio_chip->parent = dev; 318 gpio_chip->owner = THIS_MODULE; 319 gpio_chip->base = -1; 320 gpio_chip->ngpio = ngpios; 321 322 irq_chip = &p->irq_chip; 323 irq_chip->name = "gpio-em"; 324 irq_chip->irq_mask = em_gio_irq_disable; 325 irq_chip->irq_unmask = em_gio_irq_enable; 326 irq_chip->irq_set_type = em_gio_irq_set_type; 327 irq_chip->irq_request_resources = em_gio_irq_reqres; 328 irq_chip->irq_release_resources = em_gio_irq_relres; 329 irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND; 330 331 p->irq_domain = irq_domain_add_simple(dev->of_node, ngpios, 0, 332 &em_gio_irq_domain_ops, p); 333 if (!p->irq_domain) { 334 dev_err(dev, "cannot initialize irq domain\n"); 335 return -ENXIO; 336 } 337 338 ret = devm_add_action_or_reset(dev, em_gio_irq_domain_remove, 339 p->irq_domain); 340 if (ret) 341 return ret; 342 343 if (devm_request_irq(dev, irq[0], em_gio_irq_handler, 0, name, p)) { 344 dev_err(dev, "failed to request low IRQ\n"); 345 return -ENOENT; 346 } 347 348 if (devm_request_irq(dev, irq[1], em_gio_irq_handler, 0, name, p)) { 349 dev_err(dev, "failed to request high IRQ\n"); 350 return -ENOENT; 351 } 352 353 ret = devm_gpiochip_add_data(dev, gpio_chip, p); 354 if (ret) { 355 dev_err(dev, "failed to add GPIO controller\n"); 356 return ret; 357 } 358 359 return 0; 360 } 361 362 static const struct of_device_id em_gio_dt_ids[] = { 363 { .compatible = "renesas,em-gio", }, 364 {}, 365 }; 366 MODULE_DEVICE_TABLE(of, em_gio_dt_ids); 367 368 static struct platform_driver em_gio_device_driver = { 369 .probe = em_gio_probe, 370 .driver = { 371 .name = "em_gio", 372 .of_match_table = em_gio_dt_ids, 373 } 374 }; 375 376 static int __init em_gio_init(void) 377 { 378 return platform_driver_register(&em_gio_device_driver); 379 } 380 postcore_initcall(em_gio_init); 381 382 static void __exit em_gio_exit(void) 383 { 384 platform_driver_unregister(&em_gio_device_driver); 385 } 386 module_exit(em_gio_exit); 387 388 MODULE_AUTHOR("Magnus Damm"); 389 MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver"); 390 MODULE_LICENSE("GPL v2"); 391