Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Support for the GPIO/IRQ expander chips present on several HTC phones. |
| 3 | * These are implemented in CPLD chips present on the board. |
| 4 | * |
| 5 | * Copyright (c) 2007 Kevin O'Connor <kevin@koconnor.net> |
| 6 | * Copyright (c) 2007 Philipp Zabel <philipp.zabel@gmail.com> |
| 7 | * |
| 8 | * This file may be distributed under the terms of the GNU GPL license. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/interrupt.h> |
| 14 | #include <linux/irq.h> |
| 15 | #include <linux/io.h> |
| 16 | #include <linux/spinlock.h> |
| 17 | #include <linux/platform_device.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 18 | #include <linux/slab.h> |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 19 | #include <linux/module.h> |
| 20 | #include <linux/mfd/htc-egpio.h> |
| 21 | |
| 22 | struct egpio_chip { |
| 23 | int reg_start; |
| 24 | int cached_values; |
| 25 | unsigned long is_out; |
| 26 | struct device *dev; |
| 27 | struct gpio_chip chip; |
| 28 | }; |
| 29 | |
| 30 | struct egpio_info { |
| 31 | spinlock_t lock; |
| 32 | |
| 33 | /* iomem info */ |
| 34 | void __iomem *base_addr; |
| 35 | int bus_shift; /* byte shift */ |
| 36 | int reg_shift; /* bit shift */ |
| 37 | int reg_mask; |
| 38 | |
| 39 | /* irq info */ |
| 40 | int ack_register; |
| 41 | int ack_write; |
| 42 | u16 irqs_enabled; |
| 43 | uint irq_start; |
| 44 | int nirqs; |
| 45 | uint chained_irq; |
| 46 | |
| 47 | /* egpio info */ |
| 48 | struct egpio_chip *chip; |
| 49 | int nchips; |
| 50 | }; |
| 51 | |
| 52 | static inline void egpio_writew(u16 value, struct egpio_info *ei, int reg) |
| 53 | { |
| 54 | writew(value, ei->base_addr + (reg << ei->bus_shift)); |
| 55 | } |
| 56 | |
| 57 | static inline u16 egpio_readw(struct egpio_info *ei, int reg) |
| 58 | { |
| 59 | return readw(ei->base_addr + (reg << ei->bus_shift)); |
| 60 | } |
| 61 | |
| 62 | /* |
| 63 | * IRQs |
| 64 | */ |
| 65 | |
| 66 | static inline void ack_irqs(struct egpio_info *ei) |
| 67 | { |
| 68 | egpio_writew(ei->ack_write, ei, ei->ack_register); |
| 69 | pr_debug("EGPIO ack - write %x to base+%x\n", |
| 70 | ei->ack_write, ei->ack_register << ei->bus_shift); |
| 71 | } |
| 72 | |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 73 | static void egpio_ack(struct irq_data *data) |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 74 | { |
| 75 | } |
| 76 | |
| 77 | /* There does not appear to be a way to proactively mask interrupts |
| 78 | * on the egpio chip itself. So, we simply ignore interrupts that |
| 79 | * aren't desired. */ |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 80 | static void egpio_mask(struct irq_data *data) |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 81 | { |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 82 | struct egpio_info *ei = irq_data_get_irq_chip_data(data); |
| 83 | ei->irqs_enabled &= ~(1 << (data->irq - ei->irq_start)); |
| 84 | pr_debug("EGPIO mask %d %04x\n", data->irq, ei->irqs_enabled); |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 85 | } |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 86 | |
| 87 | static void egpio_unmask(struct irq_data *data) |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 88 | { |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 89 | struct egpio_info *ei = irq_data_get_irq_chip_data(data); |
| 90 | ei->irqs_enabled |= 1 << (data->irq - ei->irq_start); |
| 91 | pr_debug("EGPIO unmask %d %04x\n", data->irq, ei->irqs_enabled); |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 92 | } |
| 93 | |
| 94 | static struct irq_chip egpio_muxed_chip = { |
Mark Brown | 949b9de | 2010-12-11 16:43:59 +0000 | [diff] [blame] | 95 | .name = "htc-egpio", |
| 96 | .irq_ack = egpio_ack, |
| 97 | .irq_mask = egpio_mask, |
| 98 | .irq_unmask = egpio_unmask, |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 99 | }; |
| 100 | |
| 101 | static void egpio_handler(unsigned int irq, struct irq_desc *desc) |
| 102 | { |
| 103 | struct egpio_info *ei = get_irq_data(irq); |
| 104 | int irqpin; |
| 105 | |
| 106 | /* Read current pins. */ |
| 107 | unsigned long readval = egpio_readw(ei, ei->ack_register); |
| 108 | pr_debug("IRQ reg: %x\n", (unsigned int)readval); |
| 109 | /* Ack/unmask interrupts. */ |
| 110 | ack_irqs(ei); |
| 111 | /* Process all set pins. */ |
| 112 | readval &= ei->irqs_enabled; |
Akinobu Mita | 984b3f5 | 2010-03-05 13:41:37 -0800 | [diff] [blame] | 113 | for_each_set_bit(irqpin, &readval, ei->nirqs) { |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 114 | /* Run irq handler */ |
| 115 | pr_debug("got IRQ %d\n", irqpin); |
| 116 | irq = ei->irq_start + irqpin; |
Yinghai Lu | 08678b0 | 2008-08-19 20:50:05 -0700 | [diff] [blame] | 117 | desc = irq_to_desc(irq); |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 118 | desc->handle_irq(irq, desc); |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | int htc_egpio_get_wakeup_irq(struct device *dev) |
| 123 | { |
| 124 | struct egpio_info *ei = dev_get_drvdata(dev); |
| 125 | |
| 126 | /* Read current pins. */ |
| 127 | u16 readval = egpio_readw(ei, ei->ack_register); |
| 128 | /* Ack/unmask interrupts. */ |
| 129 | ack_irqs(ei); |
| 130 | /* Return first set pin. */ |
| 131 | readval &= ei->irqs_enabled; |
| 132 | return ei->irq_start + ffs(readval) - 1; |
| 133 | } |
| 134 | EXPORT_SYMBOL(htc_egpio_get_wakeup_irq); |
| 135 | |
| 136 | static inline int egpio_pos(struct egpio_info *ei, int bit) |
| 137 | { |
| 138 | return bit >> ei->reg_shift; |
| 139 | } |
| 140 | |
| 141 | static inline int egpio_bit(struct egpio_info *ei, int bit) |
| 142 | { |
| 143 | return 1 << (bit & ((1 << ei->reg_shift)-1)); |
| 144 | } |
| 145 | |
| 146 | /* |
| 147 | * Input pins |
| 148 | */ |
| 149 | |
| 150 | static int egpio_get(struct gpio_chip *chip, unsigned offset) |
| 151 | { |
| 152 | struct egpio_chip *egpio; |
| 153 | struct egpio_info *ei; |
| 154 | unsigned bit; |
| 155 | int reg; |
| 156 | int value; |
| 157 | |
| 158 | pr_debug("egpio_get_value(%d)\n", chip->base + offset); |
| 159 | |
| 160 | egpio = container_of(chip, struct egpio_chip, chip); |
| 161 | ei = dev_get_drvdata(egpio->dev); |
| 162 | bit = egpio_bit(ei, offset); |
| 163 | reg = egpio->reg_start + egpio_pos(ei, offset); |
| 164 | |
| 165 | value = egpio_readw(ei, reg); |
| 166 | pr_debug("readw(%p + %x) = %x\n", |
| 167 | ei->base_addr, reg << ei->bus_shift, value); |
| 168 | return value & bit; |
| 169 | } |
| 170 | |
| 171 | static int egpio_direction_input(struct gpio_chip *chip, unsigned offset) |
| 172 | { |
| 173 | struct egpio_chip *egpio; |
| 174 | |
| 175 | egpio = container_of(chip, struct egpio_chip, chip); |
| 176 | return test_bit(offset, &egpio->is_out) ? -EINVAL : 0; |
| 177 | } |
| 178 | |
| 179 | |
| 180 | /* |
| 181 | * Output pins |
| 182 | */ |
| 183 | |
| 184 | static void egpio_set(struct gpio_chip *chip, unsigned offset, int value) |
| 185 | { |
| 186 | unsigned long flag; |
| 187 | struct egpio_chip *egpio; |
| 188 | struct egpio_info *ei; |
| 189 | unsigned bit; |
| 190 | int pos; |
| 191 | int reg; |
| 192 | int shift; |
| 193 | |
| 194 | pr_debug("egpio_set(%s, %d(%d), %d)\n", |
| 195 | chip->label, offset, offset+chip->base, value); |
| 196 | |
| 197 | egpio = container_of(chip, struct egpio_chip, chip); |
| 198 | ei = dev_get_drvdata(egpio->dev); |
| 199 | bit = egpio_bit(ei, offset); |
| 200 | pos = egpio_pos(ei, offset); |
| 201 | reg = egpio->reg_start + pos; |
| 202 | shift = pos << ei->reg_shift; |
| 203 | |
| 204 | pr_debug("egpio %s: reg %d = 0x%04x\n", value ? "set" : "clear", |
| 205 | reg, (egpio->cached_values >> shift) & ei->reg_mask); |
| 206 | |
| 207 | spin_lock_irqsave(&ei->lock, flag); |
| 208 | if (value) |
| 209 | egpio->cached_values |= (1 << offset); |
| 210 | else |
| 211 | egpio->cached_values &= ~(1 << offset); |
| 212 | egpio_writew((egpio->cached_values >> shift) & ei->reg_mask, ei, reg); |
| 213 | spin_unlock_irqrestore(&ei->lock, flag); |
| 214 | } |
| 215 | |
| 216 | static int egpio_direction_output(struct gpio_chip *chip, |
| 217 | unsigned offset, int value) |
| 218 | { |
| 219 | struct egpio_chip *egpio; |
| 220 | |
| 221 | egpio = container_of(chip, struct egpio_chip, chip); |
| 222 | if (test_bit(offset, &egpio->is_out)) { |
| 223 | egpio_set(chip, offset, value); |
| 224 | return 0; |
| 225 | } else { |
| 226 | return -EINVAL; |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | static void egpio_write_cache(struct egpio_info *ei) |
| 231 | { |
| 232 | int i; |
| 233 | struct egpio_chip *egpio; |
| 234 | int shift; |
| 235 | |
| 236 | for (i = 0; i < ei->nchips; i++) { |
| 237 | egpio = &(ei->chip[i]); |
| 238 | if (!egpio->is_out) |
| 239 | continue; |
| 240 | |
| 241 | for (shift = 0; shift < egpio->chip.ngpio; |
| 242 | shift += (1<<ei->reg_shift)) { |
| 243 | |
| 244 | int reg = egpio->reg_start + egpio_pos(ei, shift); |
| 245 | |
| 246 | if (!((egpio->is_out >> shift) & ei->reg_mask)) |
| 247 | continue; |
| 248 | |
| 249 | pr_debug("EGPIO: setting %x to %x, was %x\n", reg, |
| 250 | (egpio->cached_values >> shift) & ei->reg_mask, |
| 251 | egpio_readw(ei, reg)); |
| 252 | |
| 253 | egpio_writew((egpio->cached_values >> shift) |
| 254 | & ei->reg_mask, ei, reg); |
| 255 | } |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | |
| 260 | /* |
| 261 | * Setup |
| 262 | */ |
| 263 | |
| 264 | static int __init egpio_probe(struct platform_device *pdev) |
| 265 | { |
| 266 | struct htc_egpio_platform_data *pdata = pdev->dev.platform_data; |
| 267 | struct resource *res; |
| 268 | struct egpio_info *ei; |
| 269 | struct gpio_chip *chip; |
| 270 | unsigned int irq, irq_end; |
| 271 | int i; |
| 272 | int ret; |
| 273 | |
| 274 | /* Initialize ei data structure. */ |
| 275 | ei = kzalloc(sizeof(*ei), GFP_KERNEL); |
| 276 | if (!ei) |
| 277 | return -ENOMEM; |
| 278 | |
| 279 | spin_lock_init(&ei->lock); |
| 280 | |
| 281 | /* Find chained irq */ |
| 282 | ret = -EINVAL; |
| 283 | res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); |
| 284 | if (res) |
| 285 | ei->chained_irq = res->start; |
| 286 | |
| 287 | /* Map egpio chip into virtual address space. */ |
| 288 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| 289 | if (!res) |
| 290 | goto fail; |
Philipp Zabel | 9427c34 | 2009-02-04 21:27:48 +0100 | [diff] [blame] | 291 | ei->base_addr = ioremap_nocache(res->start, resource_size(res)); |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 292 | if (!ei->base_addr) |
| 293 | goto fail; |
Samuel Ortiz | 504f97f | 2008-09-25 00:17:00 +0200 | [diff] [blame] | 294 | pr_debug("EGPIO phys=%08x virt=%p\n", (u32)res->start, ei->base_addr); |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 295 | |
| 296 | if ((pdata->bus_width != 16) && (pdata->bus_width != 32)) |
| 297 | goto fail; |
| 298 | ei->bus_shift = fls(pdata->bus_width - 1) - 3; |
| 299 | pr_debug("bus_shift = %d\n", ei->bus_shift); |
| 300 | |
| 301 | if ((pdata->reg_width != 8) && (pdata->reg_width != 16)) |
| 302 | goto fail; |
| 303 | ei->reg_shift = fls(pdata->reg_width - 1); |
| 304 | pr_debug("reg_shift = %d\n", ei->reg_shift); |
| 305 | |
| 306 | ei->reg_mask = (1 << pdata->reg_width) - 1; |
| 307 | |
| 308 | platform_set_drvdata(pdev, ei); |
| 309 | |
| 310 | ei->nchips = pdata->num_chips; |
| 311 | ei->chip = kzalloc(sizeof(struct egpio_chip) * ei->nchips, GFP_KERNEL); |
Julia Lawall | 720fd66 | 2009-02-04 20:44:01 +0100 | [diff] [blame] | 312 | if (!ei->chip) { |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 313 | ret = -ENOMEM; |
| 314 | goto fail; |
| 315 | } |
| 316 | for (i = 0; i < ei->nchips; i++) { |
| 317 | ei->chip[i].reg_start = pdata->chip[i].reg_start; |
| 318 | ei->chip[i].cached_values = pdata->chip[i].initial_values; |
| 319 | ei->chip[i].is_out = pdata->chip[i].direction; |
| 320 | ei->chip[i].dev = &(pdev->dev); |
| 321 | chip = &(ei->chip[i].chip); |
| 322 | chip->label = "htc-egpio"; |
David Brownell | d8f388d | 2008-07-25 01:46:07 -0700 | [diff] [blame] | 323 | chip->dev = &pdev->dev; |
| 324 | chip->owner = THIS_MODULE; |
Philipp Zabel | a1635b8 | 2008-04-09 19:20:34 +0100 | [diff] [blame] | 325 | chip->get = egpio_get; |
| 326 | chip->set = egpio_set; |
| 327 | chip->direction_input = egpio_direction_input; |
| 328 | chip->direction_output = egpio_direction_output; |
| 329 | chip->base = pdata->chip[i].gpio_base; |
| 330 | chip->ngpio = pdata->chip[i].num_gpios; |
| 331 | |
| 332 | gpiochip_add(chip); |
| 333 | } |
| 334 | |
| 335 | /* Set initial pin values */ |
| 336 | egpio_write_cache(ei); |
| 337 | |
| 338 | ei->irq_start = pdata->irq_base; |
| 339 | ei->nirqs = pdata->num_irqs; |
| 340 | ei->ack_register = pdata->ack_register; |
| 341 | |
| 342 | if (ei->chained_irq) { |
| 343 | /* Setup irq handlers */ |
| 344 | ei->ack_write = 0xFFFF; |
| 345 | if (pdata->invert_acks) |
| 346 | ei->ack_write = 0; |
| 347 | irq_end = ei->irq_start + ei->nirqs; |
| 348 | for (irq = ei->irq_start; irq < irq_end; irq++) { |
| 349 | set_irq_chip(irq, &egpio_muxed_chip); |
| 350 | set_irq_chip_data(irq, ei); |
| 351 | set_irq_handler(irq, handle_simple_irq); |
| 352 | set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); |
| 353 | } |
| 354 | set_irq_type(ei->chained_irq, IRQ_TYPE_EDGE_RISING); |
| 355 | set_irq_data(ei->chained_irq, ei); |
| 356 | set_irq_chained_handler(ei->chained_irq, egpio_handler); |
| 357 | ack_irqs(ei); |
| 358 | |
| 359 | device_init_wakeup(&pdev->dev, 1); |
| 360 | } |
| 361 | |
| 362 | return 0; |
| 363 | |
| 364 | fail: |
| 365 | printk(KERN_ERR "EGPIO failed to setup\n"); |
| 366 | kfree(ei); |
| 367 | return ret; |
| 368 | } |
| 369 | |
| 370 | static int __exit egpio_remove(struct platform_device *pdev) |
| 371 | { |
| 372 | struct egpio_info *ei = platform_get_drvdata(pdev); |
| 373 | unsigned int irq, irq_end; |
| 374 | |
| 375 | if (ei->chained_irq) { |
| 376 | irq_end = ei->irq_start + ei->nirqs; |
| 377 | for (irq = ei->irq_start; irq < irq_end; irq++) { |
| 378 | set_irq_chip(irq, NULL); |
| 379 | set_irq_handler(irq, NULL); |
| 380 | set_irq_flags(irq, 0); |
| 381 | } |
| 382 | set_irq_chained_handler(ei->chained_irq, NULL); |
| 383 | device_init_wakeup(&pdev->dev, 0); |
| 384 | } |
| 385 | iounmap(ei->base_addr); |
| 386 | kfree(ei->chip); |
| 387 | kfree(ei); |
| 388 | |
| 389 | return 0; |
| 390 | } |
| 391 | |
| 392 | #ifdef CONFIG_PM |
| 393 | static int egpio_suspend(struct platform_device *pdev, pm_message_t state) |
| 394 | { |
| 395 | struct egpio_info *ei = platform_get_drvdata(pdev); |
| 396 | |
| 397 | if (ei->chained_irq && device_may_wakeup(&pdev->dev)) |
| 398 | enable_irq_wake(ei->chained_irq); |
| 399 | return 0; |
| 400 | } |
| 401 | |
| 402 | static int egpio_resume(struct platform_device *pdev) |
| 403 | { |
| 404 | struct egpio_info *ei = platform_get_drvdata(pdev); |
| 405 | |
| 406 | if (ei->chained_irq && device_may_wakeup(&pdev->dev)) |
| 407 | disable_irq_wake(ei->chained_irq); |
| 408 | |
| 409 | /* Update registers from the cache, in case |
| 410 | the CPLD was powered off during suspend */ |
| 411 | egpio_write_cache(ei); |
| 412 | return 0; |
| 413 | } |
| 414 | #else |
| 415 | #define egpio_suspend NULL |
| 416 | #define egpio_resume NULL |
| 417 | #endif |
| 418 | |
| 419 | |
| 420 | static struct platform_driver egpio_driver = { |
| 421 | .driver = { |
| 422 | .name = "htc-egpio", |
| 423 | }, |
| 424 | .remove = __exit_p(egpio_remove), |
| 425 | .suspend = egpio_suspend, |
| 426 | .resume = egpio_resume, |
| 427 | }; |
| 428 | |
| 429 | static int __init egpio_init(void) |
| 430 | { |
| 431 | return platform_driver_probe(&egpio_driver, egpio_probe); |
| 432 | } |
| 433 | |
| 434 | static void __exit egpio_exit(void) |
| 435 | { |
| 436 | platform_driver_unregister(&egpio_driver); |
| 437 | } |
| 438 | |
| 439 | /* start early for dependencies */ |
| 440 | subsys_initcall(egpio_init); |
| 441 | module_exit(egpio_exit) |
| 442 | |
| 443 | MODULE_LICENSE("GPL"); |
| 444 | MODULE_AUTHOR("Kevin O'Connor <kevin@koconnor.net>"); |