| 1 | /* |
| 2 | * GPIO Chip driver for Analog Devices |
| 3 | * ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller |
| 4 | * |
| 5 | * Copyright 2009-2010 Analog Devices Inc. |
| 6 | * |
| 7 | * Licensed under the GPL-2 or later. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/slab.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/i2c.h> |
| 15 | #include <linux/gpio.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/irq.h> |
| 18 | |
| 19 | #include <linux/i2c/adp5588.h> |
| 20 | |
| 21 | #define DRV_NAME "adp5588-gpio" |
| 22 | |
| 23 | /* |
| 24 | * Early pre 4.0 Silicon required to delay readout by at least 25ms, |
| 25 | * since the Event Counter Register updated 25ms after the interrupt |
| 26 | * asserted. |
| 27 | */ |
| 28 | #define WA_DELAYED_READOUT_REVID(rev) ((rev) < 4) |
| 29 | |
| 30 | struct adp5588_gpio { |
| 31 | struct i2c_client *client; |
| 32 | struct gpio_chip gpio_chip; |
| 33 | struct mutex lock; /* protect cached dir, dat_out */ |
| 34 | /* protect serialized access to the interrupt controller bus */ |
| 35 | struct mutex irq_lock; |
| 36 | unsigned gpio_start; |
| 37 | unsigned irq_base; |
| 38 | uint8_t dat_out[3]; |
| 39 | uint8_t dir[3]; |
| 40 | uint8_t int_lvl[3]; |
| 41 | uint8_t int_en[3]; |
| 42 | uint8_t irq_mask[3]; |
| 43 | uint8_t irq_stat[3]; |
| 44 | }; |
| 45 | |
| 46 | static int adp5588_gpio_read(struct i2c_client *client, u8 reg) |
| 47 | { |
| 48 | int ret = i2c_smbus_read_byte_data(client, reg); |
| 49 | |
| 50 | if (ret < 0) |
| 51 | dev_err(&client->dev, "Read Error\n"); |
| 52 | |
| 53 | return ret; |
| 54 | } |
| 55 | |
| 56 | static int adp5588_gpio_write(struct i2c_client *client, u8 reg, u8 val) |
| 57 | { |
| 58 | int ret = i2c_smbus_write_byte_data(client, reg, val); |
| 59 | |
| 60 | if (ret < 0) |
| 61 | dev_err(&client->dev, "Write Error\n"); |
| 62 | |
| 63 | return ret; |
| 64 | } |
| 65 | |
| 66 | static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off) |
| 67 | { |
| 68 | struct adp5588_gpio *dev = gpiochip_get_data(chip); |
| 69 | unsigned bank = ADP5588_BANK(off); |
| 70 | unsigned bit = ADP5588_BIT(off); |
| 71 | int val; |
| 72 | |
| 73 | mutex_lock(&dev->lock); |
| 74 | |
| 75 | if (dev->dir[bank] & bit) |
| 76 | val = dev->dat_out[bank]; |
| 77 | else |
| 78 | val = adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + bank); |
| 79 | |
| 80 | mutex_unlock(&dev->lock); |
| 81 | |
| 82 | return !!(val & bit); |
| 83 | } |
| 84 | |
| 85 | static void adp5588_gpio_set_value(struct gpio_chip *chip, |
| 86 | unsigned off, int val) |
| 87 | { |
| 88 | unsigned bank, bit; |
| 89 | struct adp5588_gpio *dev = gpiochip_get_data(chip); |
| 90 | |
| 91 | bank = ADP5588_BANK(off); |
| 92 | bit = ADP5588_BIT(off); |
| 93 | |
| 94 | mutex_lock(&dev->lock); |
| 95 | if (val) |
| 96 | dev->dat_out[bank] |= bit; |
| 97 | else |
| 98 | dev->dat_out[bank] &= ~bit; |
| 99 | |
| 100 | adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank, |
| 101 | dev->dat_out[bank]); |
| 102 | mutex_unlock(&dev->lock); |
| 103 | } |
| 104 | |
| 105 | static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off) |
| 106 | { |
| 107 | int ret; |
| 108 | unsigned bank; |
| 109 | struct adp5588_gpio *dev = gpiochip_get_data(chip); |
| 110 | |
| 111 | bank = ADP5588_BANK(off); |
| 112 | |
| 113 | mutex_lock(&dev->lock); |
| 114 | dev->dir[bank] &= ~ADP5588_BIT(off); |
| 115 | ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]); |
| 116 | mutex_unlock(&dev->lock); |
| 117 | |
| 118 | return ret; |
| 119 | } |
| 120 | |
| 121 | static int adp5588_gpio_direction_output(struct gpio_chip *chip, |
| 122 | unsigned off, int val) |
| 123 | { |
| 124 | int ret; |
| 125 | unsigned bank, bit; |
| 126 | struct adp5588_gpio *dev = gpiochip_get_data(chip); |
| 127 | |
| 128 | bank = ADP5588_BANK(off); |
| 129 | bit = ADP5588_BIT(off); |
| 130 | |
| 131 | mutex_lock(&dev->lock); |
| 132 | dev->dir[bank] |= bit; |
| 133 | |
| 134 | if (val) |
| 135 | dev->dat_out[bank] |= bit; |
| 136 | else |
| 137 | dev->dat_out[bank] &= ~bit; |
| 138 | |
| 139 | ret = adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank, |
| 140 | dev->dat_out[bank]); |
| 141 | ret |= adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, |
| 142 | dev->dir[bank]); |
| 143 | mutex_unlock(&dev->lock); |
| 144 | |
| 145 | return ret; |
| 146 | } |
| 147 | |
| 148 | #ifdef CONFIG_GPIO_ADP5588_IRQ |
| 149 | static int adp5588_gpio_to_irq(struct gpio_chip *chip, unsigned off) |
| 150 | { |
| 151 | struct adp5588_gpio *dev = gpiochip_get_data(chip); |
| 152 | |
| 153 | return dev->irq_base + off; |
| 154 | } |
| 155 | |
| 156 | static void adp5588_irq_bus_lock(struct irq_data *d) |
| 157 | { |
| 158 | struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); |
| 159 | |
| 160 | mutex_lock(&dev->irq_lock); |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * genirq core code can issue chip->mask/unmask from atomic context. |
| 165 | * This doesn't work for slow busses where an access needs to sleep. |
| 166 | * bus_sync_unlock() is therefore called outside the atomic context, |
| 167 | * syncs the current irq mask state with the slow external controller |
| 168 | * and unlocks the bus. |
| 169 | */ |
| 170 | |
| 171 | static void adp5588_irq_bus_sync_unlock(struct irq_data *d) |
| 172 | { |
| 173 | struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); |
| 174 | int i; |
| 175 | |
| 176 | for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) |
| 177 | if (dev->int_en[i] ^ dev->irq_mask[i]) { |
| 178 | dev->int_en[i] = dev->irq_mask[i]; |
| 179 | adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i, |
| 180 | dev->int_en[i]); |
| 181 | } |
| 182 | |
| 183 | mutex_unlock(&dev->irq_lock); |
| 184 | } |
| 185 | |
| 186 | static void adp5588_irq_mask(struct irq_data *d) |
| 187 | { |
| 188 | struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); |
| 189 | unsigned gpio = d->irq - dev->irq_base; |
| 190 | |
| 191 | dev->irq_mask[ADP5588_BANK(gpio)] &= ~ADP5588_BIT(gpio); |
| 192 | } |
| 193 | |
| 194 | static void adp5588_irq_unmask(struct irq_data *d) |
| 195 | { |
| 196 | struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); |
| 197 | unsigned gpio = d->irq - dev->irq_base; |
| 198 | |
| 199 | dev->irq_mask[ADP5588_BANK(gpio)] |= ADP5588_BIT(gpio); |
| 200 | } |
| 201 | |
| 202 | static int adp5588_irq_set_type(struct irq_data *d, unsigned int type) |
| 203 | { |
| 204 | struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); |
| 205 | uint16_t gpio = d->irq - dev->irq_base; |
| 206 | unsigned bank, bit; |
| 207 | |
| 208 | if ((type & IRQ_TYPE_EDGE_BOTH)) { |
| 209 | dev_err(&dev->client->dev, "irq %d: unsupported type %d\n", |
| 210 | d->irq, type); |
| 211 | return -EINVAL; |
| 212 | } |
| 213 | |
| 214 | bank = ADP5588_BANK(gpio); |
| 215 | bit = ADP5588_BIT(gpio); |
| 216 | |
| 217 | if (type & IRQ_TYPE_LEVEL_HIGH) |
| 218 | dev->int_lvl[bank] |= bit; |
| 219 | else if (type & IRQ_TYPE_LEVEL_LOW) |
| 220 | dev->int_lvl[bank] &= ~bit; |
| 221 | else |
| 222 | return -EINVAL; |
| 223 | |
| 224 | adp5588_gpio_direction_input(&dev->gpio_chip, gpio); |
| 225 | adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank, |
| 226 | dev->int_lvl[bank]); |
| 227 | |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | static struct irq_chip adp5588_irq_chip = { |
| 232 | .name = "adp5588", |
| 233 | .irq_mask = adp5588_irq_mask, |
| 234 | .irq_unmask = adp5588_irq_unmask, |
| 235 | .irq_bus_lock = adp5588_irq_bus_lock, |
| 236 | .irq_bus_sync_unlock = adp5588_irq_bus_sync_unlock, |
| 237 | .irq_set_type = adp5588_irq_set_type, |
| 238 | }; |
| 239 | |
| 240 | static int adp5588_gpio_read_intstat(struct i2c_client *client, u8 *buf) |
| 241 | { |
| 242 | int ret = i2c_smbus_read_i2c_block_data(client, GPIO_INT_STAT1, 3, buf); |
| 243 | |
| 244 | if (ret < 0) |
| 245 | dev_err(&client->dev, "Read INT_STAT Error\n"); |
| 246 | |
| 247 | return ret; |
| 248 | } |
| 249 | |
| 250 | static irqreturn_t adp5588_irq_handler(int irq, void *devid) |
| 251 | { |
| 252 | struct adp5588_gpio *dev = devid; |
| 253 | unsigned status, bank, bit, pending; |
| 254 | int ret; |
| 255 | status = adp5588_gpio_read(dev->client, INT_STAT); |
| 256 | |
| 257 | if (status & ADP5588_GPI_INT) { |
| 258 | ret = adp5588_gpio_read_intstat(dev->client, dev->irq_stat); |
| 259 | if (ret < 0) |
| 260 | memset(dev->irq_stat, 0, ARRAY_SIZE(dev->irq_stat)); |
| 261 | |
| 262 | for (bank = 0, bit = 0; bank <= ADP5588_BANK(ADP5588_MAXGPIO); |
| 263 | bank++, bit = 0) { |
| 264 | pending = dev->irq_stat[bank] & dev->irq_mask[bank]; |
| 265 | |
| 266 | while (pending) { |
| 267 | if (pending & (1 << bit)) { |
| 268 | handle_nested_irq(dev->irq_base + |
| 269 | (bank << 3) + bit); |
| 270 | pending &= ~(1 << bit); |
| 271 | |
| 272 | } |
| 273 | bit++; |
| 274 | } |
| 275 | } |
| 276 | } |
| 277 | |
| 278 | adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */ |
| 279 | |
| 280 | return IRQ_HANDLED; |
| 281 | } |
| 282 | |
| 283 | static int adp5588_irq_setup(struct adp5588_gpio *dev) |
| 284 | { |
| 285 | struct i2c_client *client = dev->client; |
| 286 | struct adp5588_gpio_platform_data *pdata = |
| 287 | dev_get_platdata(&client->dev); |
| 288 | unsigned gpio; |
| 289 | int ret; |
| 290 | |
| 291 | adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC); |
| 292 | adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */ |
| 293 | adp5588_gpio_read_intstat(client, dev->irq_stat); /* read to clear */ |
| 294 | |
| 295 | dev->irq_base = pdata->irq_base; |
| 296 | mutex_init(&dev->irq_lock); |
| 297 | |
| 298 | for (gpio = 0; gpio < dev->gpio_chip.ngpio; gpio++) { |
| 299 | int irq = gpio + dev->irq_base; |
| 300 | irq_set_chip_data(irq, dev); |
| 301 | irq_set_chip_and_handler(irq, &adp5588_irq_chip, |
| 302 | handle_level_irq); |
| 303 | irq_set_nested_thread(irq, 1); |
| 304 | irq_modify_status(irq, IRQ_NOREQUEST, IRQ_NOPROBE); |
| 305 | } |
| 306 | |
| 307 | ret = request_threaded_irq(client->irq, |
| 308 | NULL, |
| 309 | adp5588_irq_handler, |
| 310 | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, |
| 311 | dev_name(&client->dev), dev); |
| 312 | if (ret) { |
| 313 | dev_err(&client->dev, "failed to request irq %d\n", |
| 314 | client->irq); |
| 315 | goto out; |
| 316 | } |
| 317 | |
| 318 | dev->gpio_chip.to_irq = adp5588_gpio_to_irq; |
| 319 | adp5588_gpio_write(client, CFG, |
| 320 | ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_GPI_INT); |
| 321 | |
| 322 | return 0; |
| 323 | |
| 324 | out: |
| 325 | dev->irq_base = 0; |
| 326 | return ret; |
| 327 | } |
| 328 | |
| 329 | static void adp5588_irq_teardown(struct adp5588_gpio *dev) |
| 330 | { |
| 331 | if (dev->irq_base) |
| 332 | free_irq(dev->client->irq, dev); |
| 333 | } |
| 334 | |
| 335 | #else |
| 336 | static int adp5588_irq_setup(struct adp5588_gpio *dev) |
| 337 | { |
| 338 | struct i2c_client *client = dev->client; |
| 339 | dev_warn(&client->dev, "interrupt support not compiled in\n"); |
| 340 | |
| 341 | return 0; |
| 342 | } |
| 343 | |
| 344 | static void adp5588_irq_teardown(struct adp5588_gpio *dev) |
| 345 | { |
| 346 | } |
| 347 | #endif /* CONFIG_GPIO_ADP5588_IRQ */ |
| 348 | |
| 349 | static int adp5588_gpio_probe(struct i2c_client *client, |
| 350 | const struct i2c_device_id *id) |
| 351 | { |
| 352 | struct adp5588_gpio_platform_data *pdata = |
| 353 | dev_get_platdata(&client->dev); |
| 354 | struct adp5588_gpio *dev; |
| 355 | struct gpio_chip *gc; |
| 356 | int ret, i, revid; |
| 357 | |
| 358 | if (!pdata) { |
| 359 | dev_err(&client->dev, "missing platform data\n"); |
| 360 | return -ENODEV; |
| 361 | } |
| 362 | |
| 363 | if (!i2c_check_functionality(client->adapter, |
| 364 | I2C_FUNC_SMBUS_BYTE_DATA)) { |
| 365 | dev_err(&client->dev, "SMBUS Byte Data not Supported\n"); |
| 366 | return -EIO; |
| 367 | } |
| 368 | |
| 369 | dev = devm_kzalloc(&client->dev, sizeof(*dev), GFP_KERNEL); |
| 370 | if (!dev) |
| 371 | return -ENOMEM; |
| 372 | |
| 373 | dev->client = client; |
| 374 | |
| 375 | gc = &dev->gpio_chip; |
| 376 | gc->direction_input = adp5588_gpio_direction_input; |
| 377 | gc->direction_output = adp5588_gpio_direction_output; |
| 378 | gc->get = adp5588_gpio_get_value; |
| 379 | gc->set = adp5588_gpio_set_value; |
| 380 | gc->can_sleep = true; |
| 381 | |
| 382 | gc->base = pdata->gpio_start; |
| 383 | gc->ngpio = ADP5588_MAXGPIO; |
| 384 | gc->label = client->name; |
| 385 | gc->owner = THIS_MODULE; |
| 386 | gc->names = pdata->names; |
| 387 | |
| 388 | mutex_init(&dev->lock); |
| 389 | |
| 390 | ret = adp5588_gpio_read(dev->client, DEV_ID); |
| 391 | if (ret < 0) |
| 392 | goto err; |
| 393 | |
| 394 | revid = ret & ADP5588_DEVICE_ID_MASK; |
| 395 | |
| 396 | for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) { |
| 397 | dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i); |
| 398 | dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i); |
| 399 | ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0); |
| 400 | ret |= adp5588_gpio_write(client, GPIO_PULL1 + i, |
| 401 | (pdata->pullup_dis_mask >> (8 * i)) & 0xFF); |
| 402 | ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0); |
| 403 | if (ret) |
| 404 | goto err; |
| 405 | } |
| 406 | |
| 407 | if (pdata->irq_base) { |
| 408 | if (WA_DELAYED_READOUT_REVID(revid)) { |
| 409 | dev_warn(&client->dev, "GPIO int not supported\n"); |
| 410 | } else { |
| 411 | ret = adp5588_irq_setup(dev); |
| 412 | if (ret) |
| 413 | goto err; |
| 414 | } |
| 415 | } |
| 416 | |
| 417 | ret = devm_gpiochip_add_data(&client->dev, &dev->gpio_chip, dev); |
| 418 | if (ret) |
| 419 | goto err_irq; |
| 420 | |
| 421 | dev_info(&client->dev, "IRQ Base: %d Rev.: %d\n", |
| 422 | pdata->irq_base, revid); |
| 423 | |
| 424 | if (pdata->setup) { |
| 425 | ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context); |
| 426 | if (ret < 0) |
| 427 | dev_warn(&client->dev, "setup failed, %d\n", ret); |
| 428 | } |
| 429 | |
| 430 | i2c_set_clientdata(client, dev); |
| 431 | |
| 432 | return 0; |
| 433 | |
| 434 | err_irq: |
| 435 | adp5588_irq_teardown(dev); |
| 436 | err: |
| 437 | return ret; |
| 438 | } |
| 439 | |
| 440 | static int adp5588_gpio_remove(struct i2c_client *client) |
| 441 | { |
| 442 | struct adp5588_gpio_platform_data *pdata = |
| 443 | dev_get_platdata(&client->dev); |
| 444 | struct adp5588_gpio *dev = i2c_get_clientdata(client); |
| 445 | int ret; |
| 446 | |
| 447 | if (pdata->teardown) { |
| 448 | ret = pdata->teardown(client, |
| 449 | dev->gpio_chip.base, dev->gpio_chip.ngpio, |
| 450 | pdata->context); |
| 451 | if (ret < 0) { |
| 452 | dev_err(&client->dev, "teardown failed %d\n", ret); |
| 453 | return ret; |
| 454 | } |
| 455 | } |
| 456 | |
| 457 | if (dev->irq_base) |
| 458 | free_irq(dev->client->irq, dev); |
| 459 | |
| 460 | return 0; |
| 461 | } |
| 462 | |
| 463 | static const struct i2c_device_id adp5588_gpio_id[] = { |
| 464 | {DRV_NAME, 0}, |
| 465 | {} |
| 466 | }; |
| 467 | |
| 468 | MODULE_DEVICE_TABLE(i2c, adp5588_gpio_id); |
| 469 | |
| 470 | static struct i2c_driver adp5588_gpio_driver = { |
| 471 | .driver = { |
| 472 | .name = DRV_NAME, |
| 473 | }, |
| 474 | .probe = adp5588_gpio_probe, |
| 475 | .remove = adp5588_gpio_remove, |
| 476 | .id_table = adp5588_gpio_id, |
| 477 | }; |
| 478 | |
| 479 | module_i2c_driver(adp5588_gpio_driver); |
| 480 | |
| 481 | MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); |
| 482 | MODULE_DESCRIPTION("GPIO ADP5588 Driver"); |
| 483 | MODULE_LICENSE("GPL"); |