1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * MAXIM MAX77620 GPIO driver 4 * 5 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. 6 */ 7 8 #include <linux/gpio/driver.h> 9 #include <linux/interrupt.h> 10 #include <linux/mfd/max77620.h> 11 #include <linux/module.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 15 #define GPIO_REG_ADDR(offset) (MAX77620_REG_GPIO0 + offset) 16 17 struct max77620_gpio { 18 struct gpio_chip gpio_chip; 19 struct regmap *rmap; 20 struct device *dev; 21 struct mutex buslock; /* irq_bus_lock */ 22 unsigned int irq_type[MAX77620_GPIO_NR]; 23 bool irq_enabled[MAX77620_GPIO_NR]; 24 }; 25 26 static irqreturn_t max77620_gpio_irqhandler(int irq, void *data) 27 { 28 struct max77620_gpio *gpio = data; 29 unsigned int value, offset; 30 unsigned long pending; 31 int err; 32 33 err = regmap_read(gpio->rmap, MAX77620_REG_IRQ_LVL2_GPIO, &value); 34 if (err < 0) { 35 dev_err(gpio->dev, "REG_IRQ_LVL2_GPIO read failed: %d\n", err); 36 return IRQ_NONE; 37 } 38 39 pending = value; 40 41 for_each_set_bit(offset, &pending, MAX77620_GPIO_NR) { 42 unsigned int virq; 43 44 virq = irq_find_mapping(gpio->gpio_chip.irq.domain, offset); 45 handle_nested_irq(virq); 46 } 47 48 return IRQ_HANDLED; 49 } 50 51 static void max77620_gpio_irq_mask(struct irq_data *data) 52 { 53 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 54 struct max77620_gpio *gpio = gpiochip_get_data(chip); 55 56 gpio->irq_enabled[data->hwirq] = false; 57 } 58 59 static void max77620_gpio_irq_unmask(struct irq_data *data) 60 { 61 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 62 struct max77620_gpio *gpio = gpiochip_get_data(chip); 63 64 gpio->irq_enabled[data->hwirq] = true; 65 } 66 67 static int max77620_gpio_set_irq_type(struct irq_data *data, unsigned int type) 68 { 69 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 70 struct max77620_gpio *gpio = gpiochip_get_data(chip); 71 unsigned int irq_type; 72 73 switch (type) { 74 case IRQ_TYPE_EDGE_RISING: 75 irq_type = MAX77620_CNFG_GPIO_INT_RISING; 76 break; 77 78 case IRQ_TYPE_EDGE_FALLING: 79 irq_type = MAX77620_CNFG_GPIO_INT_FALLING; 80 break; 81 82 case IRQ_TYPE_EDGE_BOTH: 83 irq_type = MAX77620_CNFG_GPIO_INT_RISING | 84 MAX77620_CNFG_GPIO_INT_FALLING; 85 break; 86 87 default: 88 return -EINVAL; 89 } 90 91 gpio->irq_type[data->hwirq] = irq_type; 92 93 return 0; 94 } 95 96 static void max77620_gpio_bus_lock(struct irq_data *data) 97 { 98 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 99 struct max77620_gpio *gpio = gpiochip_get_data(chip); 100 101 mutex_lock(&gpio->buslock); 102 } 103 104 static void max77620_gpio_bus_sync_unlock(struct irq_data *data) 105 { 106 struct gpio_chip *chip = irq_data_get_irq_chip_data(data); 107 struct max77620_gpio *gpio = gpiochip_get_data(chip); 108 unsigned int value, offset = data->hwirq; 109 int err; 110 111 value = gpio->irq_enabled[offset] ? gpio->irq_type[offset] : 0; 112 113 err = regmap_update_bits(gpio->rmap, GPIO_REG_ADDR(offset), 114 MAX77620_CNFG_GPIO_INT_MASK, value); 115 if (err < 0) 116 dev_err(chip->parent, "failed to update interrupt mask: %d\n", 117 err); 118 119 mutex_unlock(&gpio->buslock); 120 } 121 122 static struct irq_chip max77620_gpio_irqchip = { 123 .name = "max77620-gpio", 124 .irq_mask = max77620_gpio_irq_mask, 125 .irq_unmask = max77620_gpio_irq_unmask, 126 .irq_set_type = max77620_gpio_set_irq_type, 127 .irq_bus_lock = max77620_gpio_bus_lock, 128 .irq_bus_sync_unlock = max77620_gpio_bus_sync_unlock, 129 .flags = IRQCHIP_MASK_ON_SUSPEND, 130 }; 131 132 static int max77620_gpio_dir_input(struct gpio_chip *gc, unsigned int offset) 133 { 134 struct max77620_gpio *mgpio = gpiochip_get_data(gc); 135 int ret; 136 137 ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 138 MAX77620_CNFG_GPIO_DIR_MASK, 139 MAX77620_CNFG_GPIO_DIR_INPUT); 140 if (ret < 0) 141 dev_err(mgpio->dev, "CNFG_GPIOx dir update failed: %d\n", ret); 142 143 return ret; 144 } 145 146 static int max77620_gpio_get(struct gpio_chip *gc, unsigned int offset) 147 { 148 struct max77620_gpio *mgpio = gpiochip_get_data(gc); 149 unsigned int val; 150 int ret; 151 152 ret = regmap_read(mgpio->rmap, GPIO_REG_ADDR(offset), &val); 153 if (ret < 0) { 154 dev_err(mgpio->dev, "CNFG_GPIOx read failed: %d\n", ret); 155 return ret; 156 } 157 158 if (val & MAX77620_CNFG_GPIO_DIR_MASK) 159 return !!(val & MAX77620_CNFG_GPIO_INPUT_VAL_MASK); 160 else 161 return !!(val & MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK); 162 } 163 164 static int max77620_gpio_dir_output(struct gpio_chip *gc, unsigned int offset, 165 int value) 166 { 167 struct max77620_gpio *mgpio = gpiochip_get_data(gc); 168 u8 val; 169 int ret; 170 171 val = (value) ? MAX77620_CNFG_GPIO_OUTPUT_VAL_HIGH : 172 MAX77620_CNFG_GPIO_OUTPUT_VAL_LOW; 173 174 ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 175 MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK, val); 176 if (ret < 0) { 177 dev_err(mgpio->dev, "CNFG_GPIOx val update failed: %d\n", ret); 178 return ret; 179 } 180 181 ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 182 MAX77620_CNFG_GPIO_DIR_MASK, 183 MAX77620_CNFG_GPIO_DIR_OUTPUT); 184 if (ret < 0) 185 dev_err(mgpio->dev, "CNFG_GPIOx dir update failed: %d\n", ret); 186 187 return ret; 188 } 189 190 static int max77620_gpio_set_debounce(struct max77620_gpio *mgpio, 191 unsigned int offset, 192 unsigned int debounce) 193 { 194 u8 val; 195 int ret; 196 197 switch (debounce) { 198 case 0: 199 val = MAX77620_CNFG_GPIO_DBNC_None; 200 break; 201 case 1 ... 8000: 202 val = MAX77620_CNFG_GPIO_DBNC_8ms; 203 break; 204 case 8001 ... 16000: 205 val = MAX77620_CNFG_GPIO_DBNC_16ms; 206 break; 207 case 16001 ... 32000: 208 val = MAX77620_CNFG_GPIO_DBNC_32ms; 209 break; 210 default: 211 dev_err(mgpio->dev, "Illegal value %u\n", debounce); 212 return -EINVAL; 213 } 214 215 ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 216 MAX77620_CNFG_GPIO_DBNC_MASK, val); 217 if (ret < 0) 218 dev_err(mgpio->dev, "CNFG_GPIOx_DBNC update failed: %d\n", ret); 219 220 return ret; 221 } 222 223 static void max77620_gpio_set(struct gpio_chip *gc, unsigned int offset, 224 int value) 225 { 226 struct max77620_gpio *mgpio = gpiochip_get_data(gc); 227 u8 val; 228 int ret; 229 230 val = (value) ? MAX77620_CNFG_GPIO_OUTPUT_VAL_HIGH : 231 MAX77620_CNFG_GPIO_OUTPUT_VAL_LOW; 232 233 ret = regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 234 MAX77620_CNFG_GPIO_OUTPUT_VAL_MASK, val); 235 if (ret < 0) 236 dev_err(mgpio->dev, "CNFG_GPIO_OUT update failed: %d\n", ret); 237 } 238 239 static int max77620_gpio_set_config(struct gpio_chip *gc, unsigned int offset, 240 unsigned long config) 241 { 242 struct max77620_gpio *mgpio = gpiochip_get_data(gc); 243 244 switch (pinconf_to_config_param(config)) { 245 case PIN_CONFIG_DRIVE_OPEN_DRAIN: 246 return regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 247 MAX77620_CNFG_GPIO_DRV_MASK, 248 MAX77620_CNFG_GPIO_DRV_OPENDRAIN); 249 case PIN_CONFIG_DRIVE_PUSH_PULL: 250 return regmap_update_bits(mgpio->rmap, GPIO_REG_ADDR(offset), 251 MAX77620_CNFG_GPIO_DRV_MASK, 252 MAX77620_CNFG_GPIO_DRV_PUSHPULL); 253 case PIN_CONFIG_INPUT_DEBOUNCE: 254 return max77620_gpio_set_debounce(mgpio, offset, 255 pinconf_to_config_argument(config)); 256 default: 257 break; 258 } 259 260 return -ENOTSUPP; 261 } 262 263 static int max77620_gpio_irq_init_hw(struct gpio_chip *gc) 264 { 265 struct max77620_gpio *gpio = gpiochip_get_data(gc); 266 unsigned int i; 267 int err; 268 269 /* 270 * GPIO interrupts may be left ON after bootloader, hence let's 271 * pre-initialize hardware to the expected state by disabling all 272 * the interrupts. 273 */ 274 for (i = 0; i < MAX77620_GPIO_NR; i++) { 275 err = regmap_update_bits(gpio->rmap, GPIO_REG_ADDR(i), 276 MAX77620_CNFG_GPIO_INT_MASK, 0); 277 if (err < 0) { 278 dev_err(gpio->dev, 279 "failed to disable interrupt: %d\n", err); 280 return err; 281 } 282 } 283 284 return 0; 285 } 286 287 static int max77620_gpio_probe(struct platform_device *pdev) 288 { 289 struct max77620_chip *chip = dev_get_drvdata(pdev->dev.parent); 290 struct max77620_gpio *mgpio; 291 struct gpio_irq_chip *girq; 292 unsigned int gpio_irq; 293 int ret; 294 295 ret = platform_get_irq(pdev, 0); 296 if (ret < 0) 297 return ret; 298 299 gpio_irq = ret; 300 301 mgpio = devm_kzalloc(&pdev->dev, sizeof(*mgpio), GFP_KERNEL); 302 if (!mgpio) 303 return -ENOMEM; 304 305 mutex_init(&mgpio->buslock); 306 mgpio->rmap = chip->rmap; 307 mgpio->dev = &pdev->dev; 308 309 mgpio->gpio_chip.label = pdev->name; 310 mgpio->gpio_chip.parent = pdev->dev.parent; 311 mgpio->gpio_chip.direction_input = max77620_gpio_dir_input; 312 mgpio->gpio_chip.get = max77620_gpio_get; 313 mgpio->gpio_chip.direction_output = max77620_gpio_dir_output; 314 mgpio->gpio_chip.set = max77620_gpio_set; 315 mgpio->gpio_chip.set_config = max77620_gpio_set_config; 316 mgpio->gpio_chip.ngpio = MAX77620_GPIO_NR; 317 mgpio->gpio_chip.can_sleep = 1; 318 mgpio->gpio_chip.base = -1; 319 320 girq = &mgpio->gpio_chip.irq; 321 girq->chip = &max77620_gpio_irqchip; 322 /* This will let us handle the parent IRQ in the driver */ 323 girq->parent_handler = NULL; 324 girq->num_parents = 0; 325 girq->parents = NULL; 326 girq->default_type = IRQ_TYPE_NONE; 327 girq->handler = handle_edge_irq; 328 girq->init_hw = max77620_gpio_irq_init_hw; 329 girq->threaded = true; 330 331 platform_set_drvdata(pdev, mgpio); 332 333 ret = devm_gpiochip_add_data(&pdev->dev, &mgpio->gpio_chip, mgpio); 334 if (ret < 0) { 335 dev_err(&pdev->dev, "gpio_init: Failed to add max77620_gpio\n"); 336 return ret; 337 } 338 339 ret = devm_request_threaded_irq(&pdev->dev, gpio_irq, NULL, 340 max77620_gpio_irqhandler, IRQF_ONESHOT, 341 "max77620-gpio", mgpio); 342 if (ret < 0) { 343 dev_err(&pdev->dev, "failed to request IRQ: %d\n", ret); 344 return ret; 345 } 346 347 return 0; 348 } 349 350 static const struct platform_device_id max77620_gpio_devtype[] = { 351 { .name = "max77620-gpio", }, 352 { .name = "max20024-gpio", }, 353 {}, 354 }; 355 MODULE_DEVICE_TABLE(platform, max77620_gpio_devtype); 356 357 static struct platform_driver max77620_gpio_driver = { 358 .driver.name = "max77620-gpio", 359 .probe = max77620_gpio_probe, 360 .id_table = max77620_gpio_devtype, 361 }; 362 363 module_platform_driver(max77620_gpio_driver); 364 365 MODULE_DESCRIPTION("GPIO interface for MAX77620 and MAX20024 PMIC"); 366 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 367 MODULE_AUTHOR("Chaitanya Bandi <bandik@nvidia.com>"); 368 MODULE_LICENSE("GPL v2"); 369