1 /* 2 * Intel Whiskey Cove PMIC GPIO Driver 3 * 4 * This driver is written based on gpio-crystalcove.c 5 * 6 * Copyright (C) 2016 Intel Corporation. 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 version 10 * 2 as published by the Free Software Foundation. 11 * 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 18 #include <linux/bitops.h> 19 #include <linux/module.h> 20 #include <linux/interrupt.h> 21 #include <linux/gpio/driver.h> 22 #include <linux/mfd/intel_soc_pmic.h> 23 #include <linux/platform_device.h> 24 #include <linux/regmap.h> 25 #include <linux/seq_file.h> 26 27 /* 28 * Whiskey Cove PMIC has 13 physical GPIO pins divided into 3 banks: 29 * Bank 0: Pin 0 - 6 30 * Bank 1: Pin 7 - 10 31 * Bank 2: Pin 11 -12 32 * Each pin has one output control register and one input control register. 33 */ 34 #define BANK0_NR_PINS 7 35 #define BANK1_NR_PINS 4 36 #define BANK2_NR_PINS 2 37 #define WCOVE_GPIO_NUM (BANK0_NR_PINS + BANK1_NR_PINS + BANK2_NR_PINS) 38 #define WCOVE_VGPIO_NUM 94 39 /* GPIO output control registers (one per pin): 0x4e44 - 0x4e50 */ 40 #define GPIO_OUT_CTRL_BASE 0x4e44 41 /* GPIO input control registers (one per pin): 0x4e51 - 0x4e5d */ 42 #define GPIO_IN_CTRL_BASE 0x4e51 43 44 /* 45 * GPIO interrupts are organized in two groups: 46 * Group 0: Bank 0 pins (Pin 0 - 6) 47 * Group 1: Bank 1 and Bank 2 pins (Pin 7 - 12) 48 * Each group has two registers (one bit per pin): status and mask. 49 */ 50 #define GROUP0_NR_IRQS 7 51 #define GROUP1_NR_IRQS 6 52 #define IRQ_MASK_BASE 0x4e19 53 #define IRQ_STATUS_BASE 0x4e0b 54 #define UPDATE_IRQ_TYPE BIT(0) 55 #define UPDATE_IRQ_MASK BIT(1) 56 57 #define CTLI_INTCNT_DIS (0 << 1) 58 #define CTLI_INTCNT_NE (1 << 1) 59 #define CTLI_INTCNT_PE (2 << 1) 60 #define CTLI_INTCNT_BE (3 << 1) 61 62 #define CTLO_DIR_IN (0 << 5) 63 #define CTLO_DIR_OUT (1 << 5) 64 65 #define CTLO_DRV_MASK (1 << 4) 66 #define CTLO_DRV_OD (0 << 4) 67 #define CTLO_DRV_CMOS (1 << 4) 68 69 #define CTLO_DRV_REN (1 << 3) 70 71 #define CTLO_RVAL_2KDOWN (0 << 1) 72 #define CTLO_RVAL_2KUP (1 << 1) 73 #define CTLO_RVAL_50KDOWN (2 << 1) 74 #define CTLO_RVAL_50KUP (3 << 1) 75 76 #define CTLO_INPUT_SET (CTLO_DRV_CMOS | CTLO_DRV_REN | CTLO_RVAL_2KUP) 77 #define CTLO_OUTPUT_SET (CTLO_DIR_OUT | CTLO_INPUT_SET) 78 79 enum ctrl_register { 80 CTRL_IN, 81 CTRL_OUT, 82 }; 83 84 /* 85 * struct wcove_gpio - Whiskey Cove GPIO controller 86 * @buslock: for bus lock/sync and unlock. 87 * @chip: the abstract gpio_chip structure. 88 * @dev: the gpio device 89 * @regmap: the regmap from the parent device. 90 * @regmap_irq_chip: the regmap of the gpio irq chip. 91 * @update: pending IRQ setting update, to be written to the chip upon unlock. 92 * @intcnt: the Interrupt Detect value to be written. 93 * @set_irq_mask: true if the IRQ mask needs to be set, false to clear. 94 */ 95 struct wcove_gpio { 96 struct mutex buslock; 97 struct gpio_chip chip; 98 struct device *dev; 99 struct regmap *regmap; 100 struct regmap_irq_chip_data *regmap_irq_chip; 101 int update; 102 int intcnt; 103 bool set_irq_mask; 104 }; 105 106 static inline unsigned int to_reg(int gpio, enum ctrl_register reg_type) 107 { 108 unsigned int reg; 109 int bank; 110 111 if (gpio < BANK0_NR_PINS) 112 bank = 0; 113 else if (gpio < BANK0_NR_PINS + BANK1_NR_PINS) 114 bank = 1; 115 else 116 bank = 2; 117 118 if (reg_type == CTRL_IN) 119 reg = GPIO_IN_CTRL_BASE + bank; 120 else 121 reg = GPIO_OUT_CTRL_BASE + bank; 122 123 return reg; 124 } 125 126 static void wcove_update_irq_mask(struct wcove_gpio *wg, int gpio) 127 { 128 unsigned int reg, mask; 129 130 if (gpio < GROUP0_NR_IRQS) { 131 reg = IRQ_MASK_BASE; 132 mask = BIT(gpio % GROUP0_NR_IRQS); 133 } else { 134 reg = IRQ_MASK_BASE + 1; 135 mask = BIT((gpio - GROUP0_NR_IRQS) % GROUP1_NR_IRQS); 136 } 137 138 if (wg->set_irq_mask) 139 regmap_update_bits(wg->regmap, reg, mask, mask); 140 else 141 regmap_update_bits(wg->regmap, reg, mask, 0); 142 } 143 144 static void wcove_update_irq_ctrl(struct wcove_gpio *wg, int gpio) 145 { 146 unsigned int reg = to_reg(gpio, CTRL_IN); 147 148 regmap_update_bits(wg->regmap, reg, CTLI_INTCNT_BE, wg->intcnt); 149 } 150 151 static int wcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio) 152 { 153 struct wcove_gpio *wg = gpiochip_get_data(chip); 154 155 return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT), 156 CTLO_INPUT_SET); 157 } 158 159 static int wcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio, 160 int value) 161 { 162 struct wcove_gpio *wg = gpiochip_get_data(chip); 163 164 return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT), 165 CTLO_OUTPUT_SET | value); 166 } 167 168 static int wcove_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio) 169 { 170 struct wcove_gpio *wg = gpiochip_get_data(chip); 171 unsigned int val; 172 int ret; 173 174 ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &val); 175 if (ret) 176 return ret; 177 178 return !(val & CTLO_DIR_OUT); 179 } 180 181 static int wcove_gpio_get(struct gpio_chip *chip, unsigned int gpio) 182 { 183 struct wcove_gpio *wg = gpiochip_get_data(chip); 184 unsigned int val; 185 int ret; 186 187 ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &val); 188 if (ret) 189 return ret; 190 191 return val & 0x1; 192 } 193 194 static void wcove_gpio_set(struct gpio_chip *chip, 195 unsigned int gpio, int value) 196 { 197 struct wcove_gpio *wg = gpiochip_get_data(chip); 198 199 if (value) 200 regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 1); 201 else 202 regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 0); 203 } 204 205 static int wcove_gpio_set_single_ended(struct gpio_chip *chip, 206 unsigned int gpio, 207 enum single_ended_mode mode) 208 { 209 struct wcove_gpio *wg = gpiochip_get_data(chip); 210 211 switch (mode) { 212 case LINE_MODE_OPEN_DRAIN: 213 return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 214 CTLO_DRV_MASK, CTLO_DRV_OD); 215 case LINE_MODE_PUSH_PULL: 216 return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 217 CTLO_DRV_MASK, CTLO_DRV_CMOS); 218 default: 219 break; 220 } 221 222 return -ENOTSUPP; 223 } 224 225 static int wcove_irq_type(struct irq_data *data, unsigned int type) 226 { 227 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 228 struct wcove_gpio *wg = gpiochip_get_data(chip); 229 230 switch (type) { 231 case IRQ_TYPE_NONE: 232 wg->intcnt = CTLI_INTCNT_DIS; 233 break; 234 case IRQ_TYPE_EDGE_BOTH: 235 wg->intcnt = CTLI_INTCNT_BE; 236 break; 237 case IRQ_TYPE_EDGE_RISING: 238 wg->intcnt = CTLI_INTCNT_PE; 239 break; 240 case IRQ_TYPE_EDGE_FALLING: 241 wg->intcnt = CTLI_INTCNT_NE; 242 break; 243 default: 244 return -EINVAL; 245 } 246 247 wg->update |= UPDATE_IRQ_TYPE; 248 249 return 0; 250 } 251 252 static void wcove_bus_lock(struct irq_data *data) 253 { 254 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 255 struct wcove_gpio *wg = gpiochip_get_data(chip); 256 257 mutex_lock(&wg->buslock); 258 } 259 260 static void wcove_bus_sync_unlock(struct irq_data *data) 261 { 262 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 263 struct wcove_gpio *wg = gpiochip_get_data(chip); 264 int gpio = data->hwirq; 265 266 if (wg->update & UPDATE_IRQ_TYPE) 267 wcove_update_irq_ctrl(wg, gpio); 268 if (wg->update & UPDATE_IRQ_MASK) 269 wcove_update_irq_mask(wg, gpio); 270 wg->update = 0; 271 272 mutex_unlock(&wg->buslock); 273 } 274 275 static void wcove_irq_unmask(struct irq_data *data) 276 { 277 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 278 struct wcove_gpio *wg = gpiochip_get_data(chip); 279 280 wg->set_irq_mask = false; 281 wg->update |= UPDATE_IRQ_MASK; 282 } 283 284 static void wcove_irq_mask(struct irq_data *data) 285 { 286 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 287 struct wcove_gpio *wg = gpiochip_get_data(chip); 288 289 wg->set_irq_mask = true; 290 wg->update |= UPDATE_IRQ_MASK; 291 } 292 293 static struct irq_chip wcove_irqchip = { 294 .name = "Whiskey Cove", 295 .irq_mask = wcove_irq_mask, 296 .irq_unmask = wcove_irq_unmask, 297 .irq_set_type = wcove_irq_type, 298 .irq_bus_lock = wcove_bus_lock, 299 .irq_bus_sync_unlock = wcove_bus_sync_unlock, 300 }; 301 302 static irqreturn_t wcove_gpio_irq_handler(int irq, void *data) 303 { 304 struct wcove_gpio *wg = (struct wcove_gpio *)data; 305 unsigned int pending, virq, gpio, mask, offset; 306 u8 p[2]; 307 308 if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) { 309 dev_err(wg->dev, "Failed to read irq status register\n"); 310 return IRQ_NONE; 311 } 312 313 pending = p[0] | (p[1] << 8); 314 if (!pending) 315 return IRQ_NONE; 316 317 /* Iterate until no interrupt is pending */ 318 while (pending) { 319 /* One iteration is for all pending bits */ 320 for_each_set_bit(gpio, (const unsigned long *)&pending, 321 GROUP0_NR_IRQS) { 322 offset = (gpio > GROUP0_NR_IRQS) ? 1 : 0; 323 mask = (offset == 1) ? BIT(gpio - GROUP0_NR_IRQS) : 324 BIT(gpio); 325 virq = irq_find_mapping(wg->chip.irqdomain, gpio); 326 handle_nested_irq(virq); 327 regmap_update_bits(wg->regmap, IRQ_STATUS_BASE + offset, 328 mask, mask); 329 } 330 331 /* Next iteration */ 332 if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) { 333 dev_err(wg->dev, "Failed to read irq status\n"); 334 break; 335 } 336 337 pending = p[0] | (p[1] << 8); 338 } 339 340 return IRQ_HANDLED; 341 } 342 343 static void wcove_gpio_dbg_show(struct seq_file *s, 344 struct gpio_chip *chip) 345 { 346 unsigned int ctlo, ctli, irq_mask, irq_status; 347 struct wcove_gpio *wg = gpiochip_get_data(chip); 348 int gpio, offset, group, ret = 0; 349 350 for (gpio = 0; gpio < WCOVE_GPIO_NUM; gpio++) { 351 group = gpio < GROUP0_NR_IRQS ? 0 : 1; 352 ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &ctlo); 353 ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &ctli); 354 ret += regmap_read(wg->regmap, IRQ_MASK_BASE + group, 355 &irq_mask); 356 ret += regmap_read(wg->regmap, IRQ_STATUS_BASE + group, 357 &irq_status); 358 if (ret) { 359 pr_err("Failed to read registers: ctrl out/in or irq status/mask\n"); 360 break; 361 } 362 363 offset = gpio % 8; 364 seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s\n", 365 gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ", 366 ctli & 0x1 ? "hi" : "lo", 367 ctli & CTLI_INTCNT_NE ? "fall" : " ", 368 ctli & CTLI_INTCNT_PE ? "rise" : " ", 369 ctlo, 370 irq_mask & BIT(offset) ? "mask " : "unmask", 371 irq_status & BIT(offset) ? "pending" : " "); 372 } 373 } 374 375 static int wcove_gpio_probe(struct platform_device *pdev) 376 { 377 struct intel_soc_pmic *pmic; 378 struct wcove_gpio *wg; 379 int virq, ret, irq; 380 struct device *dev; 381 382 /* 383 * This gpio platform device is created by a mfd device (see 384 * drivers/mfd/intel_soc_pmic_bxtwc.c for details). Information 385 * shared by all sub-devices created by the mfd device, the regmap 386 * pointer for instance, is stored as driver data of the mfd device 387 * driver. 388 */ 389 pmic = dev_get_drvdata(pdev->dev.parent); 390 if (!pmic) 391 return -ENODEV; 392 393 irq = platform_get_irq(pdev, 0); 394 if (irq < 0) 395 return irq; 396 397 dev = &pdev->dev; 398 399 wg = devm_kzalloc(dev, sizeof(*wg), GFP_KERNEL); 400 if (!wg) 401 return -ENOMEM; 402 403 wg->regmap_irq_chip = pmic->irq_chip_data_level2; 404 405 platform_set_drvdata(pdev, wg); 406 407 mutex_init(&wg->buslock); 408 wg->chip.label = KBUILD_MODNAME; 409 wg->chip.direction_input = wcove_gpio_dir_in; 410 wg->chip.direction_output = wcove_gpio_dir_out; 411 wg->chip.get_direction = wcove_gpio_get_direction; 412 wg->chip.get = wcove_gpio_get; 413 wg->chip.set = wcove_gpio_set; 414 wg->chip.set_single_ended = wcove_gpio_set_single_ended, 415 wg->chip.base = -1; 416 wg->chip.ngpio = WCOVE_VGPIO_NUM; 417 wg->chip.can_sleep = true; 418 wg->chip.parent = pdev->dev.parent; 419 wg->chip.dbg_show = wcove_gpio_dbg_show; 420 wg->dev = dev; 421 wg->regmap = pmic->regmap; 422 423 ret = devm_gpiochip_add_data(dev, &wg->chip, wg); 424 if (ret) { 425 dev_err(dev, "Failed to add gpiochip: %d\n", ret); 426 return ret; 427 } 428 429 ret = gpiochip_irqchip_add_nested(&wg->chip, &wcove_irqchip, 0, 430 handle_simple_irq, IRQ_TYPE_NONE); 431 if (ret) { 432 dev_err(dev, "Failed to add irqchip: %d\n", ret); 433 return ret; 434 } 435 436 virq = regmap_irq_get_virq(wg->regmap_irq_chip, irq); 437 if (virq < 0) { 438 dev_err(dev, "Failed to get virq by irq %d\n", irq); 439 return virq; 440 } 441 442 ret = devm_request_threaded_irq(dev, virq, NULL, 443 wcove_gpio_irq_handler, IRQF_ONESHOT, pdev->name, wg); 444 if (ret) { 445 dev_err(dev, "Failed to request irq %d\n", virq); 446 return ret; 447 } 448 449 gpiochip_set_nested_irqchip(&wg->chip, &wcove_irqchip, virq); 450 451 return 0; 452 } 453 454 /* 455 * Whiskey Cove PMIC itself is a analog device(but with digital control 456 * interface) providing power management support for other devices in 457 * the accompanied SoC, so we have no .pm for Whiskey Cove GPIO driver. 458 */ 459 static struct platform_driver wcove_gpio_driver = { 460 .driver = { 461 .name = "bxt_wcove_gpio", 462 }, 463 .probe = wcove_gpio_probe, 464 }; 465 466 module_platform_driver(wcove_gpio_driver); 467 468 MODULE_AUTHOR("Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>"); 469 MODULE_AUTHOR("Bin Gao <bin.gao@intel.com>"); 470 MODULE_DESCRIPTION("Intel Whiskey Cove GPIO Driver"); 471 MODULE_LICENSE("GPL v2"); 472 MODULE_ALIAS("platform:bxt_wcove_gpio"); 473