1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Intel La Jolla Cove Adapter USB-GPIO driver 4 * 5 * Copyright (c) 2023, Intel Corporation. 6 */ 7 8#include <linux/acpi.h> 9#include <linux/auxiliary_bus.h> 10#include <linux/bitfield.h> 11#include <linux/bitops.h> 12#include <linux/dev_printk.h> 13#include <linux/gpio/driver.h> 14#include <linux/irq.h> 15#include <linux/kernel.h> 16#include <linux/kref.h> 17#include <linux/module.h> 18#include <linux/slab.h> 19#include <linux/types.h> 20#include <linux/usb/ljca.h> 21 22/* GPIO commands */ 23#define LJCA_GPIO_CONFIG 1 24#define LJCA_GPIO_READ 2 25#define LJCA_GPIO_WRITE 3 26#define LJCA_GPIO_INT_EVENT 4 27#define LJCA_GPIO_INT_MASK 5 28#define LJCA_GPIO_INT_UNMASK 6 29 30#define LJCA_GPIO_CONF_DISABLE BIT(0) 31#define LJCA_GPIO_CONF_INPUT BIT(1) 32#define LJCA_GPIO_CONF_OUTPUT BIT(2) 33#define LJCA_GPIO_CONF_PULLUP BIT(3) 34#define LJCA_GPIO_CONF_PULLDOWN BIT(4) 35#define LJCA_GPIO_CONF_DEFAULT BIT(5) 36#define LJCA_GPIO_CONF_INTERRUPT BIT(6) 37#define LJCA_GPIO_INT_TYPE BIT(7) 38 39#define LJCA_GPIO_CONF_EDGE FIELD_PREP(LJCA_GPIO_INT_TYPE, 1) 40#define LJCA_GPIO_CONF_LEVEL FIELD_PREP(LJCA_GPIO_INT_TYPE, 0) 41 42/* Intentional overlap with PULLUP / PULLDOWN */ 43#define LJCA_GPIO_CONF_SET BIT(3) 44#define LJCA_GPIO_CONF_CLR BIT(4) 45 46#define LJCA_GPIO_BUF_SIZE 60u 47 48struct ljca_gpio_op { 49 u8 index; 50 u8 value; 51} __packed; 52 53struct ljca_gpio_packet { 54 u8 num; 55 struct ljca_gpio_op item[] __counted_by(num); 56} __packed; 57 58struct ljca_gpio_dev { 59 struct ljca_client *ljca; 60 struct gpio_chip gc; 61 struct ljca_gpio_info *gpio_info; 62 DECLARE_BITMAP(unmasked_irqs, LJCA_MAX_GPIO_NUM); 63 DECLARE_BITMAP(enabled_irqs, LJCA_MAX_GPIO_NUM); 64 DECLARE_BITMAP(reenable_irqs, LJCA_MAX_GPIO_NUM); 65 DECLARE_BITMAP(output_enabled, LJCA_MAX_GPIO_NUM); 66 u8 *connect_mode; 67 /* protect irq bus */ 68 struct mutex irq_lock; 69 struct work_struct work; 70 /* protect package transfer to hardware */ 71 struct mutex trans_lock; 72 73 u8 obuf[LJCA_GPIO_BUF_SIZE]; 74 u8 ibuf[LJCA_GPIO_BUF_SIZE]; 75}; 76 77static int ljca_gpio_config(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id, 78 u8 config) 79{ 80 struct ljca_gpio_packet *packet = 81 (struct ljca_gpio_packet *)ljca_gpio->obuf; 82 int ret; 83 84 mutex_lock(&ljca_gpio->trans_lock); 85 packet->item[0].index = gpio_id; 86 packet->item[0].value = config | ljca_gpio->connect_mode[gpio_id]; 87 packet->num = 1; 88 89 ret = ljca_transfer(ljca_gpio->ljca, LJCA_GPIO_CONFIG, (u8 *)packet, 90 struct_size(packet, item, packet->num), NULL, 0); 91 mutex_unlock(&ljca_gpio->trans_lock); 92 93 return ret < 0 ? ret : 0; 94} 95 96static int ljca_gpio_read(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id) 97{ 98 struct ljca_gpio_packet *ack_packet = 99 (struct ljca_gpio_packet *)ljca_gpio->ibuf; 100 struct ljca_gpio_packet *packet = 101 (struct ljca_gpio_packet *)ljca_gpio->obuf; 102 int ret; 103 104 mutex_lock(&ljca_gpio->trans_lock); 105 packet->num = 1; 106 packet->item[0].index = gpio_id; 107 ret = ljca_transfer(ljca_gpio->ljca, LJCA_GPIO_READ, (u8 *)packet, 108 struct_size(packet, item, packet->num), 109 ljca_gpio->ibuf, LJCA_GPIO_BUF_SIZE); 110 111 if (ret <= 0 || ack_packet->num != packet->num) { 112 dev_err(&ljca_gpio->ljca->auxdev.dev, 113 "read package error, gpio_id: %u num: %u ret: %d\n", 114 gpio_id, ack_packet->num, ret); 115 ret = ret < 0 ? ret : -EIO; 116 } 117 mutex_unlock(&ljca_gpio->trans_lock); 118 119 return ret < 0 ? ret : ack_packet->item[0].value > 0; 120} 121 122static int ljca_gpio_write(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id, int value) 123{ 124 struct ljca_gpio_packet *packet = 125 (struct ljca_gpio_packet *)ljca_gpio->obuf; 126 int ret; 127 128 mutex_lock(&ljca_gpio->trans_lock); 129 packet->num = 1; 130 packet->item[0].index = gpio_id; 131 packet->item[0].value = value & 1; 132 133 ret = ljca_transfer(ljca_gpio->ljca, LJCA_GPIO_WRITE, (u8 *)packet, 134 struct_size(packet, item, packet->num), NULL, 0); 135 mutex_unlock(&ljca_gpio->trans_lock); 136 137 return ret < 0 ? ret : 0; 138} 139 140static int ljca_gpio_get_value(struct gpio_chip *chip, unsigned int offset) 141{ 142 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 143 144 return ljca_gpio_read(ljca_gpio, offset); 145} 146 147static void ljca_gpio_set_value(struct gpio_chip *chip, unsigned int offset, 148 int val) 149{ 150 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 151 int ret; 152 153 ret = ljca_gpio_write(ljca_gpio, offset, val); 154 if (ret) 155 dev_err(chip->parent, 156 "set value failed offset: %u val: %d ret: %d\n", 157 offset, val, ret); 158} 159 160static int ljca_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) 161{ 162 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 163 u8 config = LJCA_GPIO_CONF_INPUT | LJCA_GPIO_CONF_CLR; 164 int ret; 165 166 ret = ljca_gpio_config(ljca_gpio, offset, config); 167 if (ret) 168 return ret; 169 170 clear_bit(offset, ljca_gpio->output_enabled); 171 172 return 0; 173} 174 175static int ljca_gpio_direction_output(struct gpio_chip *chip, 176 unsigned int offset, int val) 177{ 178 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 179 u8 config = LJCA_GPIO_CONF_OUTPUT | LJCA_GPIO_CONF_CLR; 180 int ret; 181 182 ret = ljca_gpio_config(ljca_gpio, offset, config); 183 if (ret) 184 return ret; 185 186 ljca_gpio_set_value(chip, offset, val); 187 set_bit(offset, ljca_gpio->output_enabled); 188 189 return 0; 190} 191 192static int ljca_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) 193{ 194 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 195 196 if (test_bit(offset, ljca_gpio->output_enabled)) 197 return GPIO_LINE_DIRECTION_OUT; 198 199 return GPIO_LINE_DIRECTION_IN; 200} 201 202static int ljca_gpio_set_config(struct gpio_chip *chip, unsigned int offset, 203 unsigned long config) 204{ 205 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 206 207 ljca_gpio->connect_mode[offset] = 0; 208 switch (pinconf_to_config_param(config)) { 209 case PIN_CONFIG_BIAS_PULL_UP: 210 ljca_gpio->connect_mode[offset] |= LJCA_GPIO_CONF_PULLUP; 211 break; 212 case PIN_CONFIG_BIAS_PULL_DOWN: 213 ljca_gpio->connect_mode[offset] |= LJCA_GPIO_CONF_PULLDOWN; 214 break; 215 case PIN_CONFIG_DRIVE_PUSH_PULL: 216 case PIN_CONFIG_PERSIST_STATE: 217 break; 218 default: 219 return -ENOTSUPP; 220 } 221 222 return 0; 223} 224 225static int ljca_gpio_init_valid_mask(struct gpio_chip *chip, 226 unsigned long *valid_mask, 227 unsigned int ngpios) 228{ 229 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip); 230 231 WARN_ON_ONCE(ngpios != ljca_gpio->gpio_info->num); 232 bitmap_copy(valid_mask, ljca_gpio->gpio_info->valid_pin_map, ngpios); 233 234 return 0; 235} 236 237static void ljca_gpio_irq_init_valid_mask(struct gpio_chip *chip, 238 unsigned long *valid_mask, 239 unsigned int ngpios) 240{ 241 ljca_gpio_init_valid_mask(chip, valid_mask, ngpios); 242} 243 244static int ljca_enable_irq(struct ljca_gpio_dev *ljca_gpio, int gpio_id, 245 bool enable) 246{ 247 struct ljca_gpio_packet *packet = 248 (struct ljca_gpio_packet *)ljca_gpio->obuf; 249 int ret; 250 251 mutex_lock(&ljca_gpio->trans_lock); 252 packet->num = 1; 253 packet->item[0].index = gpio_id; 254 packet->item[0].value = 0; 255 256 ret = ljca_transfer(ljca_gpio->ljca, 257 enable ? LJCA_GPIO_INT_UNMASK : LJCA_GPIO_INT_MASK, 258 (u8 *)packet, struct_size(packet, item, packet->num), 259 NULL, 0); 260 mutex_unlock(&ljca_gpio->trans_lock); 261 262 return ret < 0 ? ret : 0; 263} 264 265static void ljca_gpio_async(struct work_struct *work) 266{ 267 struct ljca_gpio_dev *ljca_gpio = 268 container_of(work, struct ljca_gpio_dev, work); 269 int gpio_id, unmasked; 270 271 for_each_set_bit(gpio_id, ljca_gpio->reenable_irqs, ljca_gpio->gc.ngpio) { 272 clear_bit(gpio_id, ljca_gpio->reenable_irqs); 273 unmasked = test_bit(gpio_id, ljca_gpio->unmasked_irqs); 274 if (unmasked) 275 ljca_enable_irq(ljca_gpio, gpio_id, true); 276 } 277} 278 279static void ljca_gpio_event_cb(void *context, u8 cmd, const void *evt_data, 280 int len) 281{ 282 const struct ljca_gpio_packet *packet = evt_data; 283 struct ljca_gpio_dev *ljca_gpio = context; 284 int i, irq; 285 286 if (cmd != LJCA_GPIO_INT_EVENT) 287 return; 288 289 for (i = 0; i < packet->num; i++) { 290 irq = irq_find_mapping(ljca_gpio->gc.irq.domain, 291 packet->item[i].index); 292 if (!irq) { 293 dev_err(ljca_gpio->gc.parent, 294 "gpio_id %u does not mapped to IRQ yet\n", 295 packet->item[i].index); 296 return; 297 } 298 299 generic_handle_domain_irq(ljca_gpio->gc.irq.domain, irq); 300 set_bit(packet->item[i].index, ljca_gpio->reenable_irqs); 301 } 302 303 schedule_work(&ljca_gpio->work); 304} 305 306static void ljca_irq_unmask(struct irq_data *irqd) 307{ 308 struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); 309 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc); 310 int gpio_id = irqd_to_hwirq(irqd); 311 312 gpiochip_enable_irq(gc, gpio_id); 313 set_bit(gpio_id, ljca_gpio->unmasked_irqs); 314} 315 316static void ljca_irq_mask(struct irq_data *irqd) 317{ 318 struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); 319 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc); 320 int gpio_id = irqd_to_hwirq(irqd); 321 322 clear_bit(gpio_id, ljca_gpio->unmasked_irqs); 323 gpiochip_disable_irq(gc, gpio_id); 324} 325 326static int ljca_irq_set_type(struct irq_data *irqd, unsigned int type) 327{ 328 struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); 329 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc); 330 int gpio_id = irqd_to_hwirq(irqd); 331 332 ljca_gpio->connect_mode[gpio_id] = LJCA_GPIO_CONF_INTERRUPT; 333 switch (type) { 334 case IRQ_TYPE_LEVEL_HIGH: 335 ljca_gpio->connect_mode[gpio_id] |= 336 (LJCA_GPIO_CONF_LEVEL | LJCA_GPIO_CONF_PULLUP); 337 break; 338 case IRQ_TYPE_LEVEL_LOW: 339 ljca_gpio->connect_mode[gpio_id] |= 340 (LJCA_GPIO_CONF_LEVEL | LJCA_GPIO_CONF_PULLDOWN); 341 break; 342 case IRQ_TYPE_EDGE_BOTH: 343 break; 344 case IRQ_TYPE_EDGE_RISING: 345 ljca_gpio->connect_mode[gpio_id] |= 346 (LJCA_GPIO_CONF_EDGE | LJCA_GPIO_CONF_PULLUP); 347 break; 348 case IRQ_TYPE_EDGE_FALLING: 349 ljca_gpio->connect_mode[gpio_id] |= 350 (LJCA_GPIO_CONF_EDGE | LJCA_GPIO_CONF_PULLDOWN); 351 break; 352 default: 353 return -EINVAL; 354 } 355 356 return 0; 357} 358 359static void ljca_irq_bus_lock(struct irq_data *irqd) 360{ 361 struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); 362 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc); 363 364 mutex_lock(&ljca_gpio->irq_lock); 365} 366 367static void ljca_irq_bus_unlock(struct irq_data *irqd) 368{ 369 struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); 370 struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc); 371 int gpio_id = irqd_to_hwirq(irqd); 372 int enabled, unmasked; 373 374 enabled = test_bit(gpio_id, ljca_gpio->enabled_irqs); 375 unmasked = test_bit(gpio_id, ljca_gpio->unmasked_irqs); 376 377 if (enabled != unmasked) { 378 if (unmasked) { 379 ljca_gpio_config(ljca_gpio, gpio_id, 0); 380 ljca_enable_irq(ljca_gpio, gpio_id, true); 381 set_bit(gpio_id, ljca_gpio->enabled_irqs); 382 } else { 383 ljca_enable_irq(ljca_gpio, gpio_id, false); 384 clear_bit(gpio_id, ljca_gpio->enabled_irqs); 385 } 386 } 387 388 mutex_unlock(&ljca_gpio->irq_lock); 389} 390 391static const struct irq_chip ljca_gpio_irqchip = { 392 .name = "ljca-irq", 393 .irq_mask = ljca_irq_mask, 394 .irq_unmask = ljca_irq_unmask, 395 .irq_set_type = ljca_irq_set_type, 396 .irq_bus_lock = ljca_irq_bus_lock, 397 .irq_bus_sync_unlock = ljca_irq_bus_unlock, 398 .flags = IRQCHIP_IMMUTABLE, 399 GPIOCHIP_IRQ_RESOURCE_HELPERS, 400}; 401 402static int ljca_gpio_probe(struct auxiliary_device *auxdev, 403 const struct auxiliary_device_id *aux_dev_id) 404{ 405 struct ljca_client *ljca = auxiliary_dev_to_ljca_client(auxdev); 406 struct ljca_gpio_dev *ljca_gpio; 407 struct gpio_irq_chip *girq; 408 int ret; 409 410 ljca_gpio = devm_kzalloc(&auxdev->dev, sizeof(*ljca_gpio), GFP_KERNEL); 411 if (!ljca_gpio) 412 return -ENOMEM; 413 414 ljca_gpio->ljca = ljca; 415 ljca_gpio->gpio_info = dev_get_platdata(&auxdev->dev); 416 ljca_gpio->connect_mode = devm_kcalloc(&auxdev->dev, 417 ljca_gpio->gpio_info->num, 418 sizeof(*ljca_gpio->connect_mode), 419 GFP_KERNEL); 420 if (!ljca_gpio->connect_mode) 421 return -ENOMEM; 422 423 mutex_init(&ljca_gpio->irq_lock); 424 mutex_init(&ljca_gpio->trans_lock); 425 ljca_gpio->gc.direction_input = ljca_gpio_direction_input; 426 ljca_gpio->gc.direction_output = ljca_gpio_direction_output; 427 ljca_gpio->gc.get_direction = ljca_gpio_get_direction; 428 ljca_gpio->gc.get = ljca_gpio_get_value; 429 ljca_gpio->gc.set = ljca_gpio_set_value; 430 ljca_gpio->gc.set_config = ljca_gpio_set_config; 431 ljca_gpio->gc.init_valid_mask = ljca_gpio_init_valid_mask; 432 ljca_gpio->gc.can_sleep = true; 433 ljca_gpio->gc.parent = &auxdev->dev; 434 435 ljca_gpio->gc.base = -1; 436 ljca_gpio->gc.ngpio = ljca_gpio->gpio_info->num; 437 ljca_gpio->gc.label = ACPI_COMPANION(&auxdev->dev) ? 438 acpi_dev_name(ACPI_COMPANION(&auxdev->dev)) : 439 dev_name(&auxdev->dev); 440 ljca_gpio->gc.owner = THIS_MODULE; 441 442 auxiliary_set_drvdata(auxdev, ljca_gpio); 443 ljca_register_event_cb(ljca, ljca_gpio_event_cb, ljca_gpio); 444 445 girq = &ljca_gpio->gc.irq; 446 gpio_irq_chip_set_chip(girq, &ljca_gpio_irqchip); 447 girq->parent_handler = NULL; 448 girq->num_parents = 0; 449 girq->parents = NULL; 450 girq->default_type = IRQ_TYPE_NONE; 451 girq->handler = handle_simple_irq; 452 girq->init_valid_mask = ljca_gpio_irq_init_valid_mask; 453 454 INIT_WORK(&ljca_gpio->work, ljca_gpio_async); 455 ret = gpiochip_add_data(&ljca_gpio->gc, ljca_gpio); 456 if (ret) { 457 ljca_unregister_event_cb(ljca); 458 mutex_destroy(&ljca_gpio->irq_lock); 459 mutex_destroy(&ljca_gpio->trans_lock); 460 } 461 462 return ret; 463} 464 465static void ljca_gpio_remove(struct auxiliary_device *auxdev) 466{ 467 struct ljca_gpio_dev *ljca_gpio = auxiliary_get_drvdata(auxdev); 468 469 gpiochip_remove(&ljca_gpio->gc); 470 ljca_unregister_event_cb(ljca_gpio->ljca); 471 cancel_work_sync(&ljca_gpio->work); 472 mutex_destroy(&ljca_gpio->irq_lock); 473 mutex_destroy(&ljca_gpio->trans_lock); 474} 475 476static const struct auxiliary_device_id ljca_gpio_id_table[] = { 477 { "usb_ljca.ljca-gpio", 0 }, 478 { /* sentinel */ }, 479}; 480MODULE_DEVICE_TABLE(auxiliary, ljca_gpio_id_table); 481 482static struct auxiliary_driver ljca_gpio_driver = { 483 .probe = ljca_gpio_probe, 484 .remove = ljca_gpio_remove, 485 .id_table = ljca_gpio_id_table, 486}; 487module_auxiliary_driver(ljca_gpio_driver); 488 489MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>"); 490MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>"); 491MODULE_AUTHOR("Lixu Zhang <lixu.zhang@intel.com>"); 492MODULE_DESCRIPTION("Intel La Jolla Cove Adapter USB-GPIO driver"); 493MODULE_LICENSE("GPL"); 494MODULE_IMPORT_NS(LJCA); 495