1 /* 2 * Driver for Motorola PCAP2 as present in EZX phones 3 * 4 * Copyright (C) 2006 Harald Welte <laforge@openezx.org> 5 * Copyright (C) 2009 Daniel Ribeiro <drwyrm@gmail.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 */ 12 13 #include <linux/module.h> 14 #include <linux/kernel.h> 15 #include <linux/platform_device.h> 16 #include <linux/interrupt.h> 17 #include <linux/irq.h> 18 #include <linux/mfd/ezx-pcap.h> 19 #include <linux/spi/spi.h> 20 #include <linux/gpio.h> 21 #include <linux/slab.h> 22 23 #define PCAP_ADC_MAXQ 8 24 struct pcap_adc_request { 25 u8 bank; 26 u8 ch[2]; 27 u32 flags; 28 void (*callback)(void *, u16[]); 29 void *data; 30 }; 31 32 struct pcap_adc_sync_request { 33 u16 res[2]; 34 struct completion completion; 35 }; 36 37 struct pcap_chip { 38 struct spi_device *spi; 39 40 /* IO */ 41 u32 buf; 42 struct mutex io_mutex; 43 44 /* IRQ */ 45 unsigned int irq_base; 46 u32 msr; 47 struct work_struct isr_work; 48 struct work_struct msr_work; 49 struct workqueue_struct *workqueue; 50 51 /* ADC */ 52 struct pcap_adc_request *adc_queue[PCAP_ADC_MAXQ]; 53 u8 adc_head; 54 u8 adc_tail; 55 struct mutex adc_mutex; 56 }; 57 58 /* IO */ 59 static int ezx_pcap_putget(struct pcap_chip *pcap, u32 *data) 60 { 61 struct spi_transfer t; 62 struct spi_message m; 63 int status; 64 65 memset(&t, 0, sizeof t); 66 spi_message_init(&m); 67 t.len = sizeof(u32); 68 spi_message_add_tail(&t, &m); 69 70 pcap->buf = *data; 71 t.tx_buf = (u8 *) &pcap->buf; 72 t.rx_buf = (u8 *) &pcap->buf; 73 status = spi_sync(pcap->spi, &m); 74 75 if (status == 0) 76 *data = pcap->buf; 77 78 return status; 79 } 80 81 int ezx_pcap_write(struct pcap_chip *pcap, u8 reg_num, u32 value) 82 { 83 int ret; 84 85 mutex_lock(&pcap->io_mutex); 86 value &= PCAP_REGISTER_VALUE_MASK; 87 value |= PCAP_REGISTER_WRITE_OP_BIT 88 | (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); 89 ret = ezx_pcap_putget(pcap, &value); 90 mutex_unlock(&pcap->io_mutex); 91 92 return ret; 93 } 94 EXPORT_SYMBOL_GPL(ezx_pcap_write); 95 96 int ezx_pcap_read(struct pcap_chip *pcap, u8 reg_num, u32 *value) 97 { 98 int ret; 99 100 mutex_lock(&pcap->io_mutex); 101 *value = PCAP_REGISTER_READ_OP_BIT 102 | (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); 103 104 ret = ezx_pcap_putget(pcap, value); 105 mutex_unlock(&pcap->io_mutex); 106 107 return ret; 108 } 109 EXPORT_SYMBOL_GPL(ezx_pcap_read); 110 111 int ezx_pcap_set_bits(struct pcap_chip *pcap, u8 reg_num, u32 mask, u32 val) 112 { 113 int ret; 114 u32 tmp = PCAP_REGISTER_READ_OP_BIT | 115 (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); 116 117 mutex_lock(&pcap->io_mutex); 118 ret = ezx_pcap_putget(pcap, &tmp); 119 if (ret) 120 goto out_unlock; 121 122 tmp &= (PCAP_REGISTER_VALUE_MASK & ~mask); 123 tmp |= (val & mask) | PCAP_REGISTER_WRITE_OP_BIT | 124 (reg_num << PCAP_REGISTER_ADDRESS_SHIFT); 125 126 ret = ezx_pcap_putget(pcap, &tmp); 127 out_unlock: 128 mutex_unlock(&pcap->io_mutex); 129 130 return ret; 131 } 132 EXPORT_SYMBOL_GPL(ezx_pcap_set_bits); 133 134 /* IRQ */ 135 int irq_to_pcap(struct pcap_chip *pcap, int irq) 136 { 137 return irq - pcap->irq_base; 138 } 139 EXPORT_SYMBOL_GPL(irq_to_pcap); 140 141 int pcap_to_irq(struct pcap_chip *pcap, int irq) 142 { 143 return pcap->irq_base + irq; 144 } 145 EXPORT_SYMBOL_GPL(pcap_to_irq); 146 147 static void pcap_mask_irq(struct irq_data *d) 148 { 149 struct pcap_chip *pcap = irq_data_get_irq_chip_data(d); 150 151 pcap->msr |= 1 << irq_to_pcap(pcap, d->irq); 152 queue_work(pcap->workqueue, &pcap->msr_work); 153 } 154 155 static void pcap_unmask_irq(struct irq_data *d) 156 { 157 struct pcap_chip *pcap = irq_data_get_irq_chip_data(d); 158 159 pcap->msr &= ~(1 << irq_to_pcap(pcap, d->irq)); 160 queue_work(pcap->workqueue, &pcap->msr_work); 161 } 162 163 static struct irq_chip pcap_irq_chip = { 164 .name = "pcap", 165 .irq_disable = pcap_mask_irq, 166 .irq_mask = pcap_mask_irq, 167 .irq_unmask = pcap_unmask_irq, 168 }; 169 170 static void pcap_msr_work(struct work_struct *work) 171 { 172 struct pcap_chip *pcap = container_of(work, struct pcap_chip, msr_work); 173 174 ezx_pcap_write(pcap, PCAP_REG_MSR, pcap->msr); 175 } 176 177 static void pcap_isr_work(struct work_struct *work) 178 { 179 struct pcap_chip *pcap = container_of(work, struct pcap_chip, isr_work); 180 struct pcap_platform_data *pdata = pcap->spi->dev.platform_data; 181 u32 msr, isr, int_sel, service; 182 int irq; 183 184 do { 185 ezx_pcap_read(pcap, PCAP_REG_MSR, &msr); 186 ezx_pcap_read(pcap, PCAP_REG_ISR, &isr); 187 188 /* We can't service/ack irqs that are assigned to port 2 */ 189 if (!(pdata->config & PCAP_SECOND_PORT)) { 190 ezx_pcap_read(pcap, PCAP_REG_INT_SEL, &int_sel); 191 isr &= ~int_sel; 192 } 193 194 ezx_pcap_write(pcap, PCAP_REG_MSR, isr | msr); 195 ezx_pcap_write(pcap, PCAP_REG_ISR, isr); 196 197 local_irq_disable(); 198 service = isr & ~msr; 199 for (irq = pcap->irq_base; service; service >>= 1, irq++) { 200 if (service & 1) 201 generic_handle_irq(irq); 202 } 203 local_irq_enable(); 204 ezx_pcap_write(pcap, PCAP_REG_MSR, pcap->msr); 205 } while (gpio_get_value(pdata->gpio)); 206 } 207 208 static void pcap_irq_handler(unsigned int irq, struct irq_desc *desc) 209 { 210 struct pcap_chip *pcap = irq_get_handler_data(irq); 211 212 desc->irq_data.chip->irq_ack(&desc->irq_data); 213 queue_work(pcap->workqueue, &pcap->isr_work); 214 return; 215 } 216 217 /* ADC */ 218 void pcap_set_ts_bits(struct pcap_chip *pcap, u32 bits) 219 { 220 u32 tmp; 221 222 mutex_lock(&pcap->adc_mutex); 223 ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp); 224 tmp &= ~(PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR); 225 tmp |= bits & (PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR); 226 ezx_pcap_write(pcap, PCAP_REG_ADC, tmp); 227 mutex_unlock(&pcap->adc_mutex); 228 } 229 EXPORT_SYMBOL_GPL(pcap_set_ts_bits); 230 231 static void pcap_disable_adc(struct pcap_chip *pcap) 232 { 233 u32 tmp; 234 235 ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp); 236 tmp &= ~(PCAP_ADC_ADEN|PCAP_ADC_BATT_I_ADC|PCAP_ADC_BATT_I_POLARITY); 237 ezx_pcap_write(pcap, PCAP_REG_ADC, tmp); 238 } 239 240 static void pcap_adc_trigger(struct pcap_chip *pcap) 241 { 242 u32 tmp; 243 u8 head; 244 245 mutex_lock(&pcap->adc_mutex); 246 head = pcap->adc_head; 247 if (!pcap->adc_queue[head]) { 248 /* queue is empty, save power */ 249 pcap_disable_adc(pcap); 250 mutex_unlock(&pcap->adc_mutex); 251 return; 252 } 253 /* start conversion on requested bank, save TS_M bits */ 254 ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp); 255 tmp &= (PCAP_ADC_TS_M_MASK | PCAP_ADC_TS_REF_LOWPWR); 256 tmp |= pcap->adc_queue[head]->flags | PCAP_ADC_ADEN; 257 258 if (pcap->adc_queue[head]->bank == PCAP_ADC_BANK_1) 259 tmp |= PCAP_ADC_AD_SEL1; 260 261 ezx_pcap_write(pcap, PCAP_REG_ADC, tmp); 262 mutex_unlock(&pcap->adc_mutex); 263 ezx_pcap_write(pcap, PCAP_REG_ADR, PCAP_ADR_ASC); 264 } 265 266 static irqreturn_t pcap_adc_irq(int irq, void *_pcap) 267 { 268 struct pcap_chip *pcap = _pcap; 269 struct pcap_adc_request *req; 270 u16 res[2]; 271 u32 tmp; 272 273 mutex_lock(&pcap->adc_mutex); 274 req = pcap->adc_queue[pcap->adc_head]; 275 276 if (WARN(!req, "adc irq without pending request\n")) { 277 mutex_unlock(&pcap->adc_mutex); 278 return IRQ_HANDLED; 279 } 280 281 /* read requested channels results */ 282 ezx_pcap_read(pcap, PCAP_REG_ADC, &tmp); 283 tmp &= ~(PCAP_ADC_ADA1_MASK | PCAP_ADC_ADA2_MASK); 284 tmp |= (req->ch[0] << PCAP_ADC_ADA1_SHIFT); 285 tmp |= (req->ch[1] << PCAP_ADC_ADA2_SHIFT); 286 ezx_pcap_write(pcap, PCAP_REG_ADC, tmp); 287 ezx_pcap_read(pcap, PCAP_REG_ADR, &tmp); 288 res[0] = (tmp & PCAP_ADR_ADD1_MASK) >> PCAP_ADR_ADD1_SHIFT; 289 res[1] = (tmp & PCAP_ADR_ADD2_MASK) >> PCAP_ADR_ADD2_SHIFT; 290 291 pcap->adc_queue[pcap->adc_head] = NULL; 292 pcap->adc_head = (pcap->adc_head + 1) & (PCAP_ADC_MAXQ - 1); 293 mutex_unlock(&pcap->adc_mutex); 294 295 /* pass the results and release memory */ 296 req->callback(req->data, res); 297 kfree(req); 298 299 /* trigger next conversion (if any) on queue */ 300 pcap_adc_trigger(pcap); 301 302 return IRQ_HANDLED; 303 } 304 305 int pcap_adc_async(struct pcap_chip *pcap, u8 bank, u32 flags, u8 ch[], 306 void *callback, void *data) 307 { 308 struct pcap_adc_request *req; 309 310 /* This will be freed after we have a result */ 311 req = kmalloc(sizeof(struct pcap_adc_request), GFP_KERNEL); 312 if (!req) 313 return -ENOMEM; 314 315 req->bank = bank; 316 req->flags = flags; 317 req->ch[0] = ch[0]; 318 req->ch[1] = ch[1]; 319 req->callback = callback; 320 req->data = data; 321 322 mutex_lock(&pcap->adc_mutex); 323 if (pcap->adc_queue[pcap->adc_tail]) { 324 mutex_unlock(&pcap->adc_mutex); 325 kfree(req); 326 return -EBUSY; 327 } 328 pcap->adc_queue[pcap->adc_tail] = req; 329 pcap->adc_tail = (pcap->adc_tail + 1) & (PCAP_ADC_MAXQ - 1); 330 mutex_unlock(&pcap->adc_mutex); 331 332 /* start conversion */ 333 pcap_adc_trigger(pcap); 334 335 return 0; 336 } 337 EXPORT_SYMBOL_GPL(pcap_adc_async); 338 339 static void pcap_adc_sync_cb(void *param, u16 res[]) 340 { 341 struct pcap_adc_sync_request *req = param; 342 343 req->res[0] = res[0]; 344 req->res[1] = res[1]; 345 complete(&req->completion); 346 } 347 348 int pcap_adc_sync(struct pcap_chip *pcap, u8 bank, u32 flags, u8 ch[], 349 u16 res[]) 350 { 351 struct pcap_adc_sync_request sync_data; 352 int ret; 353 354 init_completion(&sync_data.completion); 355 ret = pcap_adc_async(pcap, bank, flags, ch, pcap_adc_sync_cb, 356 &sync_data); 357 if (ret) 358 return ret; 359 wait_for_completion(&sync_data.completion); 360 res[0] = sync_data.res[0]; 361 res[1] = sync_data.res[1]; 362 363 return 0; 364 } 365 EXPORT_SYMBOL_GPL(pcap_adc_sync); 366 367 /* subdevs */ 368 static int pcap_remove_subdev(struct device *dev, void *unused) 369 { 370 platform_device_unregister(to_platform_device(dev)); 371 return 0; 372 } 373 374 static int pcap_add_subdev(struct pcap_chip *pcap, 375 struct pcap_subdev *subdev) 376 { 377 struct platform_device *pdev; 378 int ret; 379 380 pdev = platform_device_alloc(subdev->name, subdev->id); 381 if (!pdev) 382 return -ENOMEM; 383 384 pdev->dev.parent = &pcap->spi->dev; 385 pdev->dev.platform_data = subdev->platform_data; 386 387 ret = platform_device_add(pdev); 388 if (ret) 389 platform_device_put(pdev); 390 391 return ret; 392 } 393 394 static int ezx_pcap_remove(struct spi_device *spi) 395 { 396 struct pcap_chip *pcap = dev_get_drvdata(&spi->dev); 397 struct pcap_platform_data *pdata = spi->dev.platform_data; 398 int i, adc_irq; 399 400 /* remove all registered subdevs */ 401 device_for_each_child(&spi->dev, NULL, pcap_remove_subdev); 402 403 /* cleanup ADC */ 404 adc_irq = pcap_to_irq(pcap, (pdata->config & PCAP_SECOND_PORT) ? 405 PCAP_IRQ_ADCDONE2 : PCAP_IRQ_ADCDONE); 406 free_irq(adc_irq, pcap); 407 mutex_lock(&pcap->adc_mutex); 408 for (i = 0; i < PCAP_ADC_MAXQ; i++) 409 kfree(pcap->adc_queue[i]); 410 mutex_unlock(&pcap->adc_mutex); 411 412 /* cleanup irqchip */ 413 for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++) 414 irq_set_chip_and_handler(i, NULL, NULL); 415 416 destroy_workqueue(pcap->workqueue); 417 418 kfree(pcap); 419 420 return 0; 421 } 422 423 static int ezx_pcap_probe(struct spi_device *spi) 424 { 425 struct pcap_platform_data *pdata = spi->dev.platform_data; 426 struct pcap_chip *pcap; 427 int i, adc_irq; 428 int ret = -ENODEV; 429 430 /* platform data is required */ 431 if (!pdata) 432 goto ret; 433 434 pcap = kzalloc(sizeof(*pcap), GFP_KERNEL); 435 if (!pcap) { 436 ret = -ENOMEM; 437 goto ret; 438 } 439 440 mutex_init(&pcap->io_mutex); 441 mutex_init(&pcap->adc_mutex); 442 INIT_WORK(&pcap->isr_work, pcap_isr_work); 443 INIT_WORK(&pcap->msr_work, pcap_msr_work); 444 dev_set_drvdata(&spi->dev, pcap); 445 446 /* setup spi */ 447 spi->bits_per_word = 32; 448 spi->mode = SPI_MODE_0 | (pdata->config & PCAP_CS_AH ? SPI_CS_HIGH : 0); 449 ret = spi_setup(spi); 450 if (ret) 451 goto free_pcap; 452 453 pcap->spi = spi; 454 455 /* setup irq */ 456 pcap->irq_base = pdata->irq_base; 457 pcap->workqueue = create_singlethread_workqueue("pcapd"); 458 if (!pcap->workqueue) { 459 ret = -ENOMEM; 460 dev_err(&spi->dev, "can't create pcap thread\n"); 461 goto free_pcap; 462 } 463 464 /* redirect interrupts to AP, except adcdone2 */ 465 if (!(pdata->config & PCAP_SECOND_PORT)) 466 ezx_pcap_write(pcap, PCAP_REG_INT_SEL, 467 (1 << PCAP_IRQ_ADCDONE2)); 468 469 /* setup irq chip */ 470 for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++) { 471 irq_set_chip_and_handler(i, &pcap_irq_chip, handle_simple_irq); 472 irq_set_chip_data(i, pcap); 473 #ifdef CONFIG_ARM 474 set_irq_flags(i, IRQF_VALID); 475 #else 476 irq_set_noprobe(i); 477 #endif 478 } 479 480 /* mask/ack all PCAP interrupts */ 481 ezx_pcap_write(pcap, PCAP_REG_MSR, PCAP_MASK_ALL_INTERRUPT); 482 ezx_pcap_write(pcap, PCAP_REG_ISR, PCAP_CLEAR_INTERRUPT_REGISTER); 483 pcap->msr = PCAP_MASK_ALL_INTERRUPT; 484 485 irq_set_irq_type(spi->irq, IRQ_TYPE_EDGE_RISING); 486 irq_set_handler_data(spi->irq, pcap); 487 irq_set_chained_handler(spi->irq, pcap_irq_handler); 488 irq_set_irq_wake(spi->irq, 1); 489 490 /* ADC */ 491 adc_irq = pcap_to_irq(pcap, (pdata->config & PCAP_SECOND_PORT) ? 492 PCAP_IRQ_ADCDONE2 : PCAP_IRQ_ADCDONE); 493 494 ret = request_irq(adc_irq, pcap_adc_irq, 0, "ADC", pcap); 495 if (ret) 496 goto free_irqchip; 497 498 /* setup subdevs */ 499 for (i = 0; i < pdata->num_subdevs; i++) { 500 ret = pcap_add_subdev(pcap, &pdata->subdevs[i]); 501 if (ret) 502 goto remove_subdevs; 503 } 504 505 /* board specific quirks */ 506 if (pdata->init) 507 pdata->init(pcap); 508 509 return 0; 510 511 remove_subdevs: 512 device_for_each_child(&spi->dev, NULL, pcap_remove_subdev); 513 /* free_adc: */ 514 free_irq(adc_irq, pcap); 515 free_irqchip: 516 for (i = pcap->irq_base; i < (pcap->irq_base + PCAP_NIRQS); i++) 517 irq_set_chip_and_handler(i, NULL, NULL); 518 /* destroy_workqueue: */ 519 destroy_workqueue(pcap->workqueue); 520 free_pcap: 521 kfree(pcap); 522 ret: 523 return ret; 524 } 525 526 static struct spi_driver ezxpcap_driver = { 527 .probe = ezx_pcap_probe, 528 .remove = ezx_pcap_remove, 529 .driver = { 530 .name = "ezx-pcap", 531 .owner = THIS_MODULE, 532 }, 533 }; 534 535 static int __init ezx_pcap_init(void) 536 { 537 return spi_register_driver(&ezxpcap_driver); 538 } 539 540 static void __exit ezx_pcap_exit(void) 541 { 542 spi_unregister_driver(&ezxpcap_driver); 543 } 544 545 subsys_initcall(ezx_pcap_init); 546 module_exit(ezx_pcap_exit); 547 548 MODULE_LICENSE("GPL"); 549 MODULE_AUTHOR("Daniel Ribeiro / Harald Welte"); 550 MODULE_DESCRIPTION("Motorola PCAP2 ASIC Driver"); 551 MODULE_ALIAS("spi:ezx-pcap"); 552