1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Xilinx XADC driver 4 * 5 * Copyright 2013-2014 Analog Devices Inc. 6 * Author: Lars-Peter Clausen <lars@metafoo.de> 7 * 8 * Documentation for the parts can be found at: 9 * - XADC hardmacro: Xilinx UG480 10 * - ZYNQ XADC interface: Xilinx UG585 11 * - AXI XADC interface: Xilinx PG019 12 */ 13 14 #include <linux/clk.h> 15 #include <linux/device.h> 16 #include <linux/err.h> 17 #include <linux/interrupt.h> 18 #include <linux/io.h> 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/of.h> 22 #include <linux/platform_device.h> 23 #include <linux/slab.h> 24 #include <linux/sysfs.h> 25 26 #include <linux/iio/buffer.h> 27 #include <linux/iio/events.h> 28 #include <linux/iio/iio.h> 29 #include <linux/iio/sysfs.h> 30 #include <linux/iio/trigger.h> 31 #include <linux/iio/trigger_consumer.h> 32 #include <linux/iio/triggered_buffer.h> 33 34 #include "xilinx-xadc.h" 35 36 static const unsigned int XADC_ZYNQ_UNMASK_TIMEOUT = 500; 37 38 /* ZYNQ register definitions */ 39 #define XADC_ZYNQ_REG_CFG 0x00 40 #define XADC_ZYNQ_REG_INTSTS 0x04 41 #define XADC_ZYNQ_REG_INTMSK 0x08 42 #define XADC_ZYNQ_REG_STATUS 0x0c 43 #define XADC_ZYNQ_REG_CFIFO 0x10 44 #define XADC_ZYNQ_REG_DFIFO 0x14 45 #define XADC_ZYNQ_REG_CTL 0x18 46 47 #define XADC_ZYNQ_CFG_ENABLE BIT(31) 48 #define XADC_ZYNQ_CFG_CFIFOTH_MASK (0xf << 20) 49 #define XADC_ZYNQ_CFG_CFIFOTH_OFFSET 20 50 #define XADC_ZYNQ_CFG_DFIFOTH_MASK (0xf << 16) 51 #define XADC_ZYNQ_CFG_DFIFOTH_OFFSET 16 52 #define XADC_ZYNQ_CFG_WEDGE BIT(13) 53 #define XADC_ZYNQ_CFG_REDGE BIT(12) 54 #define XADC_ZYNQ_CFG_TCKRATE_MASK (0x3 << 8) 55 #define XADC_ZYNQ_CFG_TCKRATE_DIV2 (0x0 << 8) 56 #define XADC_ZYNQ_CFG_TCKRATE_DIV4 (0x1 << 8) 57 #define XADC_ZYNQ_CFG_TCKRATE_DIV8 (0x2 << 8) 58 #define XADC_ZYNQ_CFG_TCKRATE_DIV16 (0x3 << 8) 59 #define XADC_ZYNQ_CFG_IGAP_MASK 0x1f 60 #define XADC_ZYNQ_CFG_IGAP(x) (x) 61 62 #define XADC_ZYNQ_INT_CFIFO_LTH BIT(9) 63 #define XADC_ZYNQ_INT_DFIFO_GTH BIT(8) 64 #define XADC_ZYNQ_INT_ALARM_MASK 0xff 65 #define XADC_ZYNQ_INT_ALARM_OFFSET 0 66 67 #define XADC_ZYNQ_STATUS_CFIFO_LVL_MASK (0xf << 16) 68 #define XADC_ZYNQ_STATUS_CFIFO_LVL_OFFSET 16 69 #define XADC_ZYNQ_STATUS_DFIFO_LVL_MASK (0xf << 12) 70 #define XADC_ZYNQ_STATUS_DFIFO_LVL_OFFSET 12 71 #define XADC_ZYNQ_STATUS_CFIFOF BIT(11) 72 #define XADC_ZYNQ_STATUS_CFIFOE BIT(10) 73 #define XADC_ZYNQ_STATUS_DFIFOF BIT(9) 74 #define XADC_ZYNQ_STATUS_DFIFOE BIT(8) 75 #define XADC_ZYNQ_STATUS_OT BIT(7) 76 #define XADC_ZYNQ_STATUS_ALM(x) BIT(x) 77 78 #define XADC_ZYNQ_CTL_RESET BIT(4) 79 80 #define XADC_ZYNQ_CMD_NOP 0x00 81 #define XADC_ZYNQ_CMD_READ 0x01 82 #define XADC_ZYNQ_CMD_WRITE 0x02 83 84 #define XADC_ZYNQ_CMD(cmd, addr, data) (((cmd) << 26) | ((addr) << 16) | (data)) 85 86 /* AXI register definitions */ 87 #define XADC_AXI_REG_RESET 0x00 88 #define XADC_AXI_REG_STATUS 0x04 89 #define XADC_AXI_REG_ALARM_STATUS 0x08 90 #define XADC_AXI_REG_CONVST 0x0c 91 #define XADC_AXI_REG_XADC_RESET 0x10 92 #define XADC_AXI_REG_GIER 0x5c 93 #define XADC_AXI_REG_IPISR 0x60 94 #define XADC_AXI_REG_IPIER 0x68 95 #define XADC_AXI_ADC_REG_OFFSET 0x200 96 97 #define XADC_AXI_RESET_MAGIC 0xa 98 #define XADC_AXI_GIER_ENABLE BIT(31) 99 100 #define XADC_AXI_INT_EOS BIT(4) 101 #define XADC_AXI_INT_ALARM_MASK 0x3c0f 102 103 #define XADC_FLAGS_BUFFERED BIT(0) 104 105 /* 106 * The XADC hardware supports a samplerate of up to 1MSPS. Unfortunately it does 107 * not have a hardware FIFO. Which means an interrupt is generated for each 108 * conversion sequence. At 1MSPS sample rate the CPU in ZYNQ7000 is completely 109 * overloaded by the interrupts that it soft-lockups. For this reason the driver 110 * limits the maximum samplerate 150kSPS. At this rate the CPU is fairly busy, 111 * but still responsive. 112 */ 113 #define XADC_MAX_SAMPLERATE 150000 114 115 static void xadc_write_reg(struct xadc *xadc, unsigned int reg, 116 uint32_t val) 117 { 118 writel(val, xadc->base + reg); 119 } 120 121 static void xadc_read_reg(struct xadc *xadc, unsigned int reg, 122 uint32_t *val) 123 { 124 *val = readl(xadc->base + reg); 125 } 126 127 /* 128 * The ZYNQ interface uses two asynchronous FIFOs for communication with the 129 * XADC. Reads and writes to the XADC register are performed by submitting a 130 * request to the command FIFO (CFIFO), once the request has been completed the 131 * result can be read from the data FIFO (DFIFO). The method currently used in 132 * this driver is to submit the request for a read/write operation, then go to 133 * sleep and wait for an interrupt that signals that a response is available in 134 * the data FIFO. 135 */ 136 137 static void xadc_zynq_write_fifo(struct xadc *xadc, uint32_t *cmd, 138 unsigned int n) 139 { 140 unsigned int i; 141 142 for (i = 0; i < n; i++) 143 xadc_write_reg(xadc, XADC_ZYNQ_REG_CFIFO, cmd[i]); 144 } 145 146 static void xadc_zynq_drain_fifo(struct xadc *xadc) 147 { 148 uint32_t status, tmp; 149 150 xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status); 151 152 while (!(status & XADC_ZYNQ_STATUS_DFIFOE)) { 153 xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp); 154 xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status); 155 } 156 } 157 158 static void xadc_zynq_update_intmsk(struct xadc *xadc, unsigned int mask, 159 unsigned int val) 160 { 161 xadc->zynq_intmask &= ~mask; 162 xadc->zynq_intmask |= val; 163 164 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, 165 xadc->zynq_intmask | xadc->zynq_masked_alarm); 166 } 167 168 static int xadc_zynq_write_adc_reg(struct xadc *xadc, unsigned int reg, 169 uint16_t val) 170 { 171 uint32_t cmd[1]; 172 uint32_t tmp; 173 int ret; 174 175 spin_lock_irq(&xadc->lock); 176 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 177 XADC_ZYNQ_INT_DFIFO_GTH); 178 179 reinit_completion(&xadc->completion); 180 181 cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_WRITE, reg, val); 182 xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd)); 183 xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp); 184 tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK; 185 tmp |= 0 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET; 186 xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp); 187 188 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0); 189 spin_unlock_irq(&xadc->lock); 190 191 ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ); 192 if (ret == 0) 193 ret = -EIO; 194 else 195 ret = 0; 196 197 xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp); 198 199 return ret; 200 } 201 202 static int xadc_zynq_read_adc_reg(struct xadc *xadc, unsigned int reg, 203 uint16_t *val) 204 { 205 uint32_t cmd[2]; 206 uint32_t resp, tmp; 207 int ret; 208 209 cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_READ, reg, 0); 210 cmd[1] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_NOP, 0, 0); 211 212 spin_lock_irq(&xadc->lock); 213 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 214 XADC_ZYNQ_INT_DFIFO_GTH); 215 xadc_zynq_drain_fifo(xadc); 216 reinit_completion(&xadc->completion); 217 218 xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd)); 219 xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp); 220 tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK; 221 tmp |= 1 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET; 222 xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp); 223 224 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0); 225 spin_unlock_irq(&xadc->lock); 226 ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ); 227 if (ret == 0) 228 ret = -EIO; 229 if (ret < 0) 230 return ret; 231 232 xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp); 233 xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp); 234 235 *val = resp & 0xffff; 236 237 return 0; 238 } 239 240 static unsigned int xadc_zynq_transform_alarm(unsigned int alarm) 241 { 242 return ((alarm & 0x80) >> 4) | 243 ((alarm & 0x78) << 1) | 244 (alarm & 0x07); 245 } 246 247 /* 248 * The ZYNQ threshold interrupts are level sensitive. Since we can't make the 249 * threshold condition go way from within the interrupt handler, this means as 250 * soon as a threshold condition is present we would enter the interrupt handler 251 * again and again. To work around this we mask all active thresholds interrupts 252 * in the interrupt handler and start a timer. In this timer we poll the 253 * interrupt status and only if the interrupt is inactive we unmask it again. 254 */ 255 static void xadc_zynq_unmask_worker(struct work_struct *work) 256 { 257 struct xadc *xadc = container_of(work, struct xadc, zynq_unmask_work.work); 258 unsigned int misc_sts, unmask; 259 260 xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &misc_sts); 261 262 misc_sts &= XADC_ZYNQ_INT_ALARM_MASK; 263 264 spin_lock_irq(&xadc->lock); 265 266 /* Clear those bits which are not active anymore */ 267 unmask = (xadc->zynq_masked_alarm ^ misc_sts) & xadc->zynq_masked_alarm; 268 xadc->zynq_masked_alarm &= misc_sts; 269 270 /* Also clear those which are masked out anyway */ 271 xadc->zynq_masked_alarm &= ~xadc->zynq_intmask; 272 273 /* Clear the interrupts before we unmask them */ 274 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, unmask); 275 276 xadc_zynq_update_intmsk(xadc, 0, 0); 277 278 spin_unlock_irq(&xadc->lock); 279 280 /* if still pending some alarm re-trigger the timer */ 281 if (xadc->zynq_masked_alarm) { 282 schedule_delayed_work(&xadc->zynq_unmask_work, 283 msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT)); 284 } 285 286 } 287 288 static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid) 289 { 290 struct iio_dev *indio_dev = devid; 291 struct xadc *xadc = iio_priv(indio_dev); 292 uint32_t status; 293 294 xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status); 295 296 status &= ~(xadc->zynq_intmask | xadc->zynq_masked_alarm); 297 298 if (!status) 299 return IRQ_NONE; 300 301 spin_lock(&xadc->lock); 302 303 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status); 304 305 if (status & XADC_ZYNQ_INT_DFIFO_GTH) { 306 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 307 XADC_ZYNQ_INT_DFIFO_GTH); 308 complete(&xadc->completion); 309 } 310 311 status &= XADC_ZYNQ_INT_ALARM_MASK; 312 if (status) { 313 xadc->zynq_masked_alarm |= status; 314 /* 315 * mask the current event interrupt, 316 * unmask it when the interrupt is no more active. 317 */ 318 xadc_zynq_update_intmsk(xadc, 0, 0); 319 320 xadc_handle_events(indio_dev, 321 xadc_zynq_transform_alarm(status)); 322 323 /* unmask the required interrupts in timer. */ 324 schedule_delayed_work(&xadc->zynq_unmask_work, 325 msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT)); 326 } 327 spin_unlock(&xadc->lock); 328 329 return IRQ_HANDLED; 330 } 331 332 #define XADC_ZYNQ_TCK_RATE_MAX 50000000 333 #define XADC_ZYNQ_IGAP_DEFAULT 20 334 #define XADC_ZYNQ_PCAP_RATE_MAX 200000000 335 336 static int xadc_zynq_setup(struct platform_device *pdev, 337 struct iio_dev *indio_dev, int irq) 338 { 339 struct xadc *xadc = iio_priv(indio_dev); 340 unsigned long pcap_rate; 341 unsigned int tck_div; 342 unsigned int div; 343 unsigned int igap; 344 unsigned int tck_rate; 345 int ret; 346 347 /* TODO: Figure out how to make igap and tck_rate configurable */ 348 igap = XADC_ZYNQ_IGAP_DEFAULT; 349 tck_rate = XADC_ZYNQ_TCK_RATE_MAX; 350 351 xadc->zynq_intmask = ~0; 352 353 pcap_rate = clk_get_rate(xadc->clk); 354 if (!pcap_rate) 355 return -EINVAL; 356 357 if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) { 358 ret = clk_set_rate(xadc->clk, 359 (unsigned long)XADC_ZYNQ_PCAP_RATE_MAX); 360 if (ret) 361 return ret; 362 } 363 364 if (tck_rate > pcap_rate / 2) { 365 div = 2; 366 } else { 367 div = pcap_rate / tck_rate; 368 if (pcap_rate / div > XADC_ZYNQ_TCK_RATE_MAX) 369 div++; 370 } 371 372 if (div <= 3) 373 tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV2; 374 else if (div <= 7) 375 tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV4; 376 else if (div <= 15) 377 tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV8; 378 else 379 tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV16; 380 381 xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, XADC_ZYNQ_CTL_RESET); 382 xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, 0); 383 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, ~0); 384 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, xadc->zynq_intmask); 385 xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, XADC_ZYNQ_CFG_ENABLE | 386 XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE | 387 tck_div | XADC_ZYNQ_CFG_IGAP(igap)); 388 389 if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) { 390 ret = clk_set_rate(xadc->clk, pcap_rate); 391 if (ret) 392 return ret; 393 } 394 395 return 0; 396 } 397 398 static unsigned long xadc_zynq_get_dclk_rate(struct xadc *xadc) 399 { 400 unsigned int div; 401 uint32_t val; 402 403 xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &val); 404 405 switch (val & XADC_ZYNQ_CFG_TCKRATE_MASK) { 406 case XADC_ZYNQ_CFG_TCKRATE_DIV4: 407 div = 4; 408 break; 409 case XADC_ZYNQ_CFG_TCKRATE_DIV8: 410 div = 8; 411 break; 412 case XADC_ZYNQ_CFG_TCKRATE_DIV16: 413 div = 16; 414 break; 415 default: 416 div = 2; 417 break; 418 } 419 420 return clk_get_rate(xadc->clk) / div; 421 } 422 423 static void xadc_zynq_update_alarm(struct xadc *xadc, unsigned int alarm) 424 { 425 unsigned long flags; 426 uint32_t status; 427 428 /* Move OT to bit 7 */ 429 alarm = ((alarm & 0x08) << 4) | ((alarm & 0xf0) >> 1) | (alarm & 0x07); 430 431 spin_lock_irqsave(&xadc->lock, flags); 432 433 /* Clear previous interrupts if any. */ 434 xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status); 435 xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status & alarm); 436 437 xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_ALARM_MASK, 438 ~alarm & XADC_ZYNQ_INT_ALARM_MASK); 439 440 spin_unlock_irqrestore(&xadc->lock, flags); 441 } 442 443 static const struct xadc_ops xadc_zynq_ops = { 444 .read = xadc_zynq_read_adc_reg, 445 .write = xadc_zynq_write_adc_reg, 446 .setup = xadc_zynq_setup, 447 .get_dclk_rate = xadc_zynq_get_dclk_rate, 448 .interrupt_handler = xadc_zynq_interrupt_handler, 449 .update_alarm = xadc_zynq_update_alarm, 450 }; 451 452 static int xadc_axi_read_adc_reg(struct xadc *xadc, unsigned int reg, 453 uint16_t *val) 454 { 455 uint32_t val32; 456 457 xadc_read_reg(xadc, XADC_AXI_ADC_REG_OFFSET + reg * 4, &val32); 458 *val = val32 & 0xffff; 459 460 return 0; 461 } 462 463 static int xadc_axi_write_adc_reg(struct xadc *xadc, unsigned int reg, 464 uint16_t val) 465 { 466 xadc_write_reg(xadc, XADC_AXI_ADC_REG_OFFSET + reg * 4, val); 467 468 return 0; 469 } 470 471 static int xadc_axi_setup(struct platform_device *pdev, 472 struct iio_dev *indio_dev, int irq) 473 { 474 struct xadc *xadc = iio_priv(indio_dev); 475 476 xadc_write_reg(xadc, XADC_AXI_REG_RESET, XADC_AXI_RESET_MAGIC); 477 xadc_write_reg(xadc, XADC_AXI_REG_GIER, XADC_AXI_GIER_ENABLE); 478 479 return 0; 480 } 481 482 static irqreturn_t xadc_axi_interrupt_handler(int irq, void *devid) 483 { 484 struct iio_dev *indio_dev = devid; 485 struct xadc *xadc = iio_priv(indio_dev); 486 uint32_t status, mask; 487 unsigned int events; 488 489 xadc_read_reg(xadc, XADC_AXI_REG_IPISR, &status); 490 xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &mask); 491 status &= mask; 492 493 if (!status) 494 return IRQ_NONE; 495 496 if ((status & XADC_AXI_INT_EOS) && xadc->trigger) 497 iio_trigger_poll(xadc->trigger); 498 499 if (status & XADC_AXI_INT_ALARM_MASK) { 500 /* 501 * The order of the bits in the AXI-XADC status register does 502 * not match the order of the bits in the XADC alarm enable 503 * register. xadc_handle_events() expects the events to be in 504 * the same order as the XADC alarm enable register. 505 */ 506 events = (status & 0x000e) >> 1; 507 events |= (status & 0x0001) << 3; 508 events |= (status & 0x3c00) >> 6; 509 xadc_handle_events(indio_dev, events); 510 } 511 512 xadc_write_reg(xadc, XADC_AXI_REG_IPISR, status); 513 514 return IRQ_HANDLED; 515 } 516 517 static void xadc_axi_update_alarm(struct xadc *xadc, unsigned int alarm) 518 { 519 uint32_t val; 520 unsigned long flags; 521 522 /* 523 * The order of the bits in the AXI-XADC status register does not match 524 * the order of the bits in the XADC alarm enable register. We get 525 * passed the alarm mask in the same order as in the XADC alarm enable 526 * register. 527 */ 528 alarm = ((alarm & 0x07) << 1) | ((alarm & 0x08) >> 3) | 529 ((alarm & 0xf0) << 6); 530 531 spin_lock_irqsave(&xadc->lock, flags); 532 xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); 533 val &= ~XADC_AXI_INT_ALARM_MASK; 534 val |= alarm; 535 xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val); 536 spin_unlock_irqrestore(&xadc->lock, flags); 537 } 538 539 static unsigned long xadc_axi_get_dclk(struct xadc *xadc) 540 { 541 return clk_get_rate(xadc->clk); 542 } 543 544 static const struct xadc_ops xadc_axi_ops = { 545 .read = xadc_axi_read_adc_reg, 546 .write = xadc_axi_write_adc_reg, 547 .setup = xadc_axi_setup, 548 .get_dclk_rate = xadc_axi_get_dclk, 549 .update_alarm = xadc_axi_update_alarm, 550 .interrupt_handler = xadc_axi_interrupt_handler, 551 .flags = XADC_FLAGS_BUFFERED, 552 }; 553 554 static int _xadc_update_adc_reg(struct xadc *xadc, unsigned int reg, 555 uint16_t mask, uint16_t val) 556 { 557 uint16_t tmp; 558 int ret; 559 560 ret = _xadc_read_adc_reg(xadc, reg, &tmp); 561 if (ret) 562 return ret; 563 564 return _xadc_write_adc_reg(xadc, reg, (tmp & ~mask) | val); 565 } 566 567 static int xadc_update_adc_reg(struct xadc *xadc, unsigned int reg, 568 uint16_t mask, uint16_t val) 569 { 570 int ret; 571 572 mutex_lock(&xadc->mutex); 573 ret = _xadc_update_adc_reg(xadc, reg, mask, val); 574 mutex_unlock(&xadc->mutex); 575 576 return ret; 577 } 578 579 static unsigned long xadc_get_dclk_rate(struct xadc *xadc) 580 { 581 return xadc->ops->get_dclk_rate(xadc); 582 } 583 584 static int xadc_update_scan_mode(struct iio_dev *indio_dev, 585 const unsigned long *mask) 586 { 587 struct xadc *xadc = iio_priv(indio_dev); 588 unsigned int n; 589 590 n = bitmap_weight(mask, indio_dev->masklength); 591 592 kfree(xadc->data); 593 xadc->data = kcalloc(n, sizeof(*xadc->data), GFP_KERNEL); 594 if (!xadc->data) 595 return -ENOMEM; 596 597 return 0; 598 } 599 600 static unsigned int xadc_scan_index_to_channel(unsigned int scan_index) 601 { 602 switch (scan_index) { 603 case 5: 604 return XADC_REG_VCCPINT; 605 case 6: 606 return XADC_REG_VCCPAUX; 607 case 7: 608 return XADC_REG_VCCO_DDR; 609 case 8: 610 return XADC_REG_TEMP; 611 case 9: 612 return XADC_REG_VCCINT; 613 case 10: 614 return XADC_REG_VCCAUX; 615 case 11: 616 return XADC_REG_VPVN; 617 case 12: 618 return XADC_REG_VREFP; 619 case 13: 620 return XADC_REG_VREFN; 621 case 14: 622 return XADC_REG_VCCBRAM; 623 default: 624 return XADC_REG_VAUX(scan_index - 16); 625 } 626 } 627 628 static irqreturn_t xadc_trigger_handler(int irq, void *p) 629 { 630 struct iio_poll_func *pf = p; 631 struct iio_dev *indio_dev = pf->indio_dev; 632 struct xadc *xadc = iio_priv(indio_dev); 633 unsigned int chan; 634 int i, j; 635 636 if (!xadc->data) 637 goto out; 638 639 j = 0; 640 for_each_set_bit(i, indio_dev->active_scan_mask, 641 indio_dev->masklength) { 642 chan = xadc_scan_index_to_channel(i); 643 xadc_read_adc_reg(xadc, chan, &xadc->data[j]); 644 j++; 645 } 646 647 iio_push_to_buffers(indio_dev, xadc->data); 648 649 out: 650 iio_trigger_notify_done(indio_dev->trig); 651 652 return IRQ_HANDLED; 653 } 654 655 static int xadc_trigger_set_state(struct iio_trigger *trigger, bool state) 656 { 657 struct xadc *xadc = iio_trigger_get_drvdata(trigger); 658 unsigned long flags; 659 unsigned int convst; 660 unsigned int val; 661 int ret = 0; 662 663 mutex_lock(&xadc->mutex); 664 665 if (state) { 666 /* Only one of the two triggers can be active at a time. */ 667 if (xadc->trigger != NULL) { 668 ret = -EBUSY; 669 goto err_out; 670 } else { 671 xadc->trigger = trigger; 672 if (trigger == xadc->convst_trigger) 673 convst = XADC_CONF0_EC; 674 else 675 convst = 0; 676 } 677 ret = _xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF0_EC, 678 convst); 679 if (ret) 680 goto err_out; 681 } else { 682 xadc->trigger = NULL; 683 } 684 685 spin_lock_irqsave(&xadc->lock, flags); 686 xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); 687 xadc_write_reg(xadc, XADC_AXI_REG_IPISR, XADC_AXI_INT_EOS); 688 if (state) 689 val |= XADC_AXI_INT_EOS; 690 else 691 val &= ~XADC_AXI_INT_EOS; 692 xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val); 693 spin_unlock_irqrestore(&xadc->lock, flags); 694 695 err_out: 696 mutex_unlock(&xadc->mutex); 697 698 return ret; 699 } 700 701 static const struct iio_trigger_ops xadc_trigger_ops = { 702 .set_trigger_state = &xadc_trigger_set_state, 703 }; 704 705 static struct iio_trigger *xadc_alloc_trigger(struct iio_dev *indio_dev, 706 const char *name) 707 { 708 struct iio_trigger *trig; 709 int ret; 710 711 trig = iio_trigger_alloc("%s%d-%s", indio_dev->name, 712 indio_dev->id, name); 713 if (trig == NULL) 714 return ERR_PTR(-ENOMEM); 715 716 trig->dev.parent = indio_dev->dev.parent; 717 trig->ops = &xadc_trigger_ops; 718 iio_trigger_set_drvdata(trig, iio_priv(indio_dev)); 719 720 ret = iio_trigger_register(trig); 721 if (ret) 722 goto error_free_trig; 723 724 return trig; 725 726 error_free_trig: 727 iio_trigger_free(trig); 728 return ERR_PTR(ret); 729 } 730 731 static int xadc_power_adc_b(struct xadc *xadc, unsigned int seq_mode) 732 { 733 uint16_t val; 734 735 /* Powerdown the ADC-B when it is not needed. */ 736 switch (seq_mode) { 737 case XADC_CONF1_SEQ_SIMULTANEOUS: 738 case XADC_CONF1_SEQ_INDEPENDENT: 739 val = 0; 740 break; 741 default: 742 val = XADC_CONF2_PD_ADC_B; 743 break; 744 } 745 746 return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_PD_MASK, 747 val); 748 } 749 750 static int xadc_get_seq_mode(struct xadc *xadc, unsigned long scan_mode) 751 { 752 unsigned int aux_scan_mode = scan_mode >> 16; 753 754 if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_DUAL) 755 return XADC_CONF1_SEQ_SIMULTANEOUS; 756 757 if ((aux_scan_mode & 0xff00) == 0 || 758 (aux_scan_mode & 0x00ff) == 0) 759 return XADC_CONF1_SEQ_CONTINUOUS; 760 761 return XADC_CONF1_SEQ_SIMULTANEOUS; 762 } 763 764 static int xadc_postdisable(struct iio_dev *indio_dev) 765 { 766 struct xadc *xadc = iio_priv(indio_dev); 767 unsigned long scan_mask; 768 int ret; 769 int i; 770 771 scan_mask = 1; /* Run calibration as part of the sequence */ 772 for (i = 0; i < indio_dev->num_channels; i++) 773 scan_mask |= BIT(indio_dev->channels[i].scan_index); 774 775 /* Enable all channels and calibration */ 776 ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff); 777 if (ret) 778 return ret; 779 780 ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16); 781 if (ret) 782 return ret; 783 784 ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, 785 XADC_CONF1_SEQ_CONTINUOUS); 786 if (ret) 787 return ret; 788 789 return xadc_power_adc_b(xadc, XADC_CONF1_SEQ_CONTINUOUS); 790 } 791 792 static int xadc_preenable(struct iio_dev *indio_dev) 793 { 794 struct xadc *xadc = iio_priv(indio_dev); 795 unsigned long scan_mask; 796 int seq_mode; 797 int ret; 798 799 ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, 800 XADC_CONF1_SEQ_DEFAULT); 801 if (ret) 802 goto err; 803 804 scan_mask = *indio_dev->active_scan_mask; 805 seq_mode = xadc_get_seq_mode(xadc, scan_mask); 806 807 ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff); 808 if (ret) 809 goto err; 810 811 /* 812 * In simultaneous mode the upper and lower aux channels are samples at 813 * the same time. In this mode the upper 8 bits in the sequencer 814 * register are don't care and the lower 8 bits control two channels 815 * each. As such we must set the bit if either the channel in the lower 816 * group or the upper group is enabled. 817 */ 818 if (seq_mode == XADC_CONF1_SEQ_SIMULTANEOUS) 819 scan_mask = ((scan_mask >> 8) | scan_mask) & 0xff0000; 820 821 ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16); 822 if (ret) 823 goto err; 824 825 ret = xadc_power_adc_b(xadc, seq_mode); 826 if (ret) 827 goto err; 828 829 ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, 830 seq_mode); 831 if (ret) 832 goto err; 833 834 return 0; 835 err: 836 xadc_postdisable(indio_dev); 837 return ret; 838 } 839 840 static const struct iio_buffer_setup_ops xadc_buffer_ops = { 841 .preenable = &xadc_preenable, 842 .postenable = &iio_triggered_buffer_postenable, 843 .predisable = &iio_triggered_buffer_predisable, 844 .postdisable = &xadc_postdisable, 845 }; 846 847 static int xadc_read_samplerate(struct xadc *xadc) 848 { 849 unsigned int div; 850 uint16_t val16; 851 int ret; 852 853 ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, &val16); 854 if (ret) 855 return ret; 856 857 div = (val16 & XADC_CONF2_DIV_MASK) >> XADC_CONF2_DIV_OFFSET; 858 if (div < 2) 859 div = 2; 860 861 return xadc_get_dclk_rate(xadc) / div / 26; 862 } 863 864 static int xadc_read_raw(struct iio_dev *indio_dev, 865 struct iio_chan_spec const *chan, int *val, int *val2, long info) 866 { 867 struct xadc *xadc = iio_priv(indio_dev); 868 uint16_t val16; 869 int ret; 870 871 switch (info) { 872 case IIO_CHAN_INFO_RAW: 873 if (iio_buffer_enabled(indio_dev)) 874 return -EBUSY; 875 ret = xadc_read_adc_reg(xadc, chan->address, &val16); 876 if (ret < 0) 877 return ret; 878 879 val16 >>= 4; 880 if (chan->scan_type.sign == 'u') 881 *val = val16; 882 else 883 *val = sign_extend32(val16, 11); 884 885 return IIO_VAL_INT; 886 case IIO_CHAN_INFO_SCALE: 887 switch (chan->type) { 888 case IIO_VOLTAGE: 889 /* V = (val * 3.0) / 4096 */ 890 switch (chan->address) { 891 case XADC_REG_VCCINT: 892 case XADC_REG_VCCAUX: 893 case XADC_REG_VREFP: 894 case XADC_REG_VREFN: 895 case XADC_REG_VCCBRAM: 896 case XADC_REG_VCCPINT: 897 case XADC_REG_VCCPAUX: 898 case XADC_REG_VCCO_DDR: 899 *val = 3000; 900 break; 901 default: 902 *val = 1000; 903 break; 904 } 905 *val2 = 12; 906 return IIO_VAL_FRACTIONAL_LOG2; 907 case IIO_TEMP: 908 /* Temp in C = (val * 503.975) / 4096 - 273.15 */ 909 *val = 503975; 910 *val2 = 12; 911 return IIO_VAL_FRACTIONAL_LOG2; 912 default: 913 return -EINVAL; 914 } 915 case IIO_CHAN_INFO_OFFSET: 916 /* Only the temperature channel has an offset */ 917 *val = -((273150 << 12) / 503975); 918 return IIO_VAL_INT; 919 case IIO_CHAN_INFO_SAMP_FREQ: 920 ret = xadc_read_samplerate(xadc); 921 if (ret < 0) 922 return ret; 923 924 *val = ret; 925 return IIO_VAL_INT; 926 default: 927 return -EINVAL; 928 } 929 } 930 931 static int xadc_write_samplerate(struct xadc *xadc, int val) 932 { 933 unsigned long clk_rate = xadc_get_dclk_rate(xadc); 934 unsigned int div; 935 936 if (!clk_rate) 937 return -EINVAL; 938 939 if (val <= 0) 940 return -EINVAL; 941 942 /* Max. 150 kSPS */ 943 if (val > XADC_MAX_SAMPLERATE) 944 val = XADC_MAX_SAMPLERATE; 945 946 val *= 26; 947 948 /* Min 1MHz */ 949 if (val < 1000000) 950 val = 1000000; 951 952 /* 953 * We want to round down, but only if we do not exceed the 150 kSPS 954 * limit. 955 */ 956 div = clk_rate / val; 957 if (clk_rate / div / 26 > XADC_MAX_SAMPLERATE) 958 div++; 959 if (div < 2) 960 div = 2; 961 else if (div > 0xff) 962 div = 0xff; 963 964 return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_DIV_MASK, 965 div << XADC_CONF2_DIV_OFFSET); 966 } 967 968 static int xadc_write_raw(struct iio_dev *indio_dev, 969 struct iio_chan_spec const *chan, int val, int val2, long info) 970 { 971 struct xadc *xadc = iio_priv(indio_dev); 972 973 if (info != IIO_CHAN_INFO_SAMP_FREQ) 974 return -EINVAL; 975 976 return xadc_write_samplerate(xadc, val); 977 } 978 979 static const struct iio_event_spec xadc_temp_events[] = { 980 { 981 .type = IIO_EV_TYPE_THRESH, 982 .dir = IIO_EV_DIR_RISING, 983 .mask_separate = BIT(IIO_EV_INFO_ENABLE) | 984 BIT(IIO_EV_INFO_VALUE) | 985 BIT(IIO_EV_INFO_HYSTERESIS), 986 }, 987 }; 988 989 /* Separate values for upper and lower thresholds, but only a shared enabled */ 990 static const struct iio_event_spec xadc_voltage_events[] = { 991 { 992 .type = IIO_EV_TYPE_THRESH, 993 .dir = IIO_EV_DIR_RISING, 994 .mask_separate = BIT(IIO_EV_INFO_VALUE), 995 }, { 996 .type = IIO_EV_TYPE_THRESH, 997 .dir = IIO_EV_DIR_FALLING, 998 .mask_separate = BIT(IIO_EV_INFO_VALUE), 999 }, { 1000 .type = IIO_EV_TYPE_THRESH, 1001 .dir = IIO_EV_DIR_EITHER, 1002 .mask_separate = BIT(IIO_EV_INFO_ENABLE), 1003 }, 1004 }; 1005 1006 #define XADC_CHAN_TEMP(_chan, _scan_index, _addr) { \ 1007 .type = IIO_TEMP, \ 1008 .indexed = 1, \ 1009 .channel = (_chan), \ 1010 .address = (_addr), \ 1011 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 1012 BIT(IIO_CHAN_INFO_SCALE) | \ 1013 BIT(IIO_CHAN_INFO_OFFSET), \ 1014 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 1015 .event_spec = xadc_temp_events, \ 1016 .num_event_specs = ARRAY_SIZE(xadc_temp_events), \ 1017 .scan_index = (_scan_index), \ 1018 .scan_type = { \ 1019 .sign = 'u', \ 1020 .realbits = 12, \ 1021 .storagebits = 16, \ 1022 .shift = 4, \ 1023 .endianness = IIO_CPU, \ 1024 }, \ 1025 } 1026 1027 #define XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) { \ 1028 .type = IIO_VOLTAGE, \ 1029 .indexed = 1, \ 1030 .channel = (_chan), \ 1031 .address = (_addr), \ 1032 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 1033 BIT(IIO_CHAN_INFO_SCALE), \ 1034 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 1035 .event_spec = (_alarm) ? xadc_voltage_events : NULL, \ 1036 .num_event_specs = (_alarm) ? ARRAY_SIZE(xadc_voltage_events) : 0, \ 1037 .scan_index = (_scan_index), \ 1038 .scan_type = { \ 1039 .sign = ((_addr) == XADC_REG_VREFN) ? 's' : 'u', \ 1040 .realbits = 12, \ 1041 .storagebits = 16, \ 1042 .shift = 4, \ 1043 .endianness = IIO_CPU, \ 1044 }, \ 1045 .extend_name = _ext, \ 1046 } 1047 1048 static const struct iio_chan_spec xadc_channels[] = { 1049 XADC_CHAN_TEMP(0, 8, XADC_REG_TEMP), 1050 XADC_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true), 1051 XADC_CHAN_VOLTAGE(1, 10, XADC_REG_VCCAUX, "vccaux", true), 1052 XADC_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true), 1053 XADC_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpint", true), 1054 XADC_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpaux", true), 1055 XADC_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccoddr", true), 1056 XADC_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false), 1057 XADC_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false), 1058 XADC_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false), 1059 XADC_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false), 1060 XADC_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false), 1061 XADC_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false), 1062 XADC_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false), 1063 XADC_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false), 1064 XADC_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false), 1065 XADC_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false), 1066 XADC_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false), 1067 XADC_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false), 1068 XADC_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false), 1069 XADC_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false), 1070 XADC_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false), 1071 XADC_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false), 1072 XADC_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false), 1073 XADC_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false), 1074 XADC_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false), 1075 }; 1076 1077 static const struct iio_info xadc_info = { 1078 .read_raw = &xadc_read_raw, 1079 .write_raw = &xadc_write_raw, 1080 .read_event_config = &xadc_read_event_config, 1081 .write_event_config = &xadc_write_event_config, 1082 .read_event_value = &xadc_read_event_value, 1083 .write_event_value = &xadc_write_event_value, 1084 .update_scan_mode = &xadc_update_scan_mode, 1085 }; 1086 1087 static const struct of_device_id xadc_of_match_table[] = { 1088 { .compatible = "xlnx,zynq-xadc-1.00.a", (void *)&xadc_zynq_ops }, 1089 { .compatible = "xlnx,axi-xadc-1.00.a", (void *)&xadc_axi_ops }, 1090 { }, 1091 }; 1092 MODULE_DEVICE_TABLE(of, xadc_of_match_table); 1093 1094 static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np, 1095 unsigned int *conf) 1096 { 1097 struct xadc *xadc = iio_priv(indio_dev); 1098 struct iio_chan_spec *channels, *chan; 1099 struct device_node *chan_node, *child; 1100 unsigned int num_channels; 1101 const char *external_mux; 1102 u32 ext_mux_chan; 1103 u32 reg; 1104 int ret; 1105 1106 *conf = 0; 1107 1108 ret = of_property_read_string(np, "xlnx,external-mux", &external_mux); 1109 if (ret < 0 || strcasecmp(external_mux, "none") == 0) 1110 xadc->external_mux_mode = XADC_EXTERNAL_MUX_NONE; 1111 else if (strcasecmp(external_mux, "single") == 0) 1112 xadc->external_mux_mode = XADC_EXTERNAL_MUX_SINGLE; 1113 else if (strcasecmp(external_mux, "dual") == 0) 1114 xadc->external_mux_mode = XADC_EXTERNAL_MUX_DUAL; 1115 else 1116 return -EINVAL; 1117 1118 if (xadc->external_mux_mode != XADC_EXTERNAL_MUX_NONE) { 1119 ret = of_property_read_u32(np, "xlnx,external-mux-channel", 1120 &ext_mux_chan); 1121 if (ret < 0) 1122 return ret; 1123 1124 if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_SINGLE) { 1125 if (ext_mux_chan == 0) 1126 ext_mux_chan = XADC_REG_VPVN; 1127 else if (ext_mux_chan <= 16) 1128 ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1); 1129 else 1130 return -EINVAL; 1131 } else { 1132 if (ext_mux_chan > 0 && ext_mux_chan <= 8) 1133 ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1); 1134 else 1135 return -EINVAL; 1136 } 1137 1138 *conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan); 1139 } 1140 1141 channels = kmemdup(xadc_channels, sizeof(xadc_channels), GFP_KERNEL); 1142 if (!channels) 1143 return -ENOMEM; 1144 1145 num_channels = 9; 1146 chan = &channels[9]; 1147 1148 chan_node = of_get_child_by_name(np, "xlnx,channels"); 1149 if (chan_node) { 1150 for_each_child_of_node(chan_node, child) { 1151 if (num_channels >= ARRAY_SIZE(xadc_channels)) { 1152 of_node_put(child); 1153 break; 1154 } 1155 1156 ret = of_property_read_u32(child, "reg", ®); 1157 if (ret || reg > 16) 1158 continue; 1159 1160 if (of_property_read_bool(child, "xlnx,bipolar")) 1161 chan->scan_type.sign = 's'; 1162 1163 if (reg == 0) { 1164 chan->scan_index = 11; 1165 chan->address = XADC_REG_VPVN; 1166 } else { 1167 chan->scan_index = 15 + reg; 1168 chan->address = XADC_REG_VAUX(reg - 1); 1169 } 1170 num_channels++; 1171 chan++; 1172 } 1173 } 1174 of_node_put(chan_node); 1175 1176 indio_dev->num_channels = num_channels; 1177 indio_dev->channels = krealloc(channels, sizeof(*channels) * 1178 num_channels, GFP_KERNEL); 1179 /* If we can't resize the channels array, just use the original */ 1180 if (!indio_dev->channels) 1181 indio_dev->channels = channels; 1182 1183 return 0; 1184 } 1185 1186 static int xadc_probe(struct platform_device *pdev) 1187 { 1188 const struct of_device_id *id; 1189 struct iio_dev *indio_dev; 1190 unsigned int bipolar_mask; 1191 unsigned int conf0; 1192 struct xadc *xadc; 1193 int ret; 1194 int irq; 1195 int i; 1196 1197 if (!pdev->dev.of_node) 1198 return -ENODEV; 1199 1200 id = of_match_node(xadc_of_match_table, pdev->dev.of_node); 1201 if (!id) 1202 return -EINVAL; 1203 1204 irq = platform_get_irq(pdev, 0); 1205 if (irq <= 0) 1206 return -ENXIO; 1207 1208 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*xadc)); 1209 if (!indio_dev) 1210 return -ENOMEM; 1211 1212 xadc = iio_priv(indio_dev); 1213 xadc->ops = id->data; 1214 xadc->irq = irq; 1215 init_completion(&xadc->completion); 1216 mutex_init(&xadc->mutex); 1217 spin_lock_init(&xadc->lock); 1218 INIT_DELAYED_WORK(&xadc->zynq_unmask_work, xadc_zynq_unmask_worker); 1219 1220 xadc->base = devm_platform_ioremap_resource(pdev, 0); 1221 if (IS_ERR(xadc->base)) 1222 return PTR_ERR(xadc->base); 1223 1224 indio_dev->dev.parent = &pdev->dev; 1225 indio_dev->dev.of_node = pdev->dev.of_node; 1226 indio_dev->name = "xadc"; 1227 indio_dev->modes = INDIO_DIRECT_MODE; 1228 indio_dev->info = &xadc_info; 1229 1230 ret = xadc_parse_dt(indio_dev, pdev->dev.of_node, &conf0); 1231 if (ret) 1232 goto err_device_free; 1233 1234 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) { 1235 ret = iio_triggered_buffer_setup(indio_dev, 1236 &iio_pollfunc_store_time, &xadc_trigger_handler, 1237 &xadc_buffer_ops); 1238 if (ret) 1239 goto err_device_free; 1240 1241 xadc->convst_trigger = xadc_alloc_trigger(indio_dev, "convst"); 1242 if (IS_ERR(xadc->convst_trigger)) { 1243 ret = PTR_ERR(xadc->convst_trigger); 1244 goto err_triggered_buffer_cleanup; 1245 } 1246 xadc->samplerate_trigger = xadc_alloc_trigger(indio_dev, 1247 "samplerate"); 1248 if (IS_ERR(xadc->samplerate_trigger)) { 1249 ret = PTR_ERR(xadc->samplerate_trigger); 1250 goto err_free_convst_trigger; 1251 } 1252 } 1253 1254 xadc->clk = devm_clk_get(&pdev->dev, NULL); 1255 if (IS_ERR(xadc->clk)) { 1256 ret = PTR_ERR(xadc->clk); 1257 goto err_free_samplerate_trigger; 1258 } 1259 1260 ret = clk_prepare_enable(xadc->clk); 1261 if (ret) 1262 goto err_free_samplerate_trigger; 1263 1264 /* 1265 * Make sure not to exceed the maximum samplerate since otherwise the 1266 * resulting interrupt storm will soft-lock the system. 1267 */ 1268 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) { 1269 ret = xadc_read_samplerate(xadc); 1270 if (ret < 0) 1271 goto err_free_samplerate_trigger; 1272 if (ret > XADC_MAX_SAMPLERATE) { 1273 ret = xadc_write_samplerate(xadc, XADC_MAX_SAMPLERATE); 1274 if (ret < 0) 1275 goto err_free_samplerate_trigger; 1276 } 1277 } 1278 1279 ret = request_irq(xadc->irq, xadc->ops->interrupt_handler, 0, 1280 dev_name(&pdev->dev), indio_dev); 1281 if (ret) 1282 goto err_clk_disable_unprepare; 1283 1284 ret = xadc->ops->setup(pdev, indio_dev, xadc->irq); 1285 if (ret) 1286 goto err_free_irq; 1287 1288 for (i = 0; i < 16; i++) 1289 xadc_read_adc_reg(xadc, XADC_REG_THRESHOLD(i), 1290 &xadc->threshold[i]); 1291 1292 ret = xadc_write_adc_reg(xadc, XADC_REG_CONF0, conf0); 1293 if (ret) 1294 goto err_free_irq; 1295 1296 bipolar_mask = 0; 1297 for (i = 0; i < indio_dev->num_channels; i++) { 1298 if (indio_dev->channels[i].scan_type.sign == 's') 1299 bipolar_mask |= BIT(indio_dev->channels[i].scan_index); 1300 } 1301 1302 ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(0), bipolar_mask); 1303 if (ret) 1304 goto err_free_irq; 1305 ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(1), 1306 bipolar_mask >> 16); 1307 if (ret) 1308 goto err_free_irq; 1309 1310 /* Disable all alarms */ 1311 ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK, 1312 XADC_CONF1_ALARM_MASK); 1313 if (ret) 1314 goto err_free_irq; 1315 1316 /* Set thresholds to min/max */ 1317 for (i = 0; i < 16; i++) { 1318 /* 1319 * Set max voltage threshold and both temperature thresholds to 1320 * 0xffff, min voltage threshold to 0. 1321 */ 1322 if (i % 8 < 4 || i == 7) 1323 xadc->threshold[i] = 0xffff; 1324 else 1325 xadc->threshold[i] = 0; 1326 ret = xadc_write_adc_reg(xadc, XADC_REG_THRESHOLD(i), 1327 xadc->threshold[i]); 1328 if (ret) 1329 goto err_free_irq; 1330 } 1331 1332 /* Go to non-buffered mode */ 1333 xadc_postdisable(indio_dev); 1334 1335 ret = iio_device_register(indio_dev); 1336 if (ret) 1337 goto err_free_irq; 1338 1339 platform_set_drvdata(pdev, indio_dev); 1340 1341 return 0; 1342 1343 err_free_irq: 1344 free_irq(xadc->irq, indio_dev); 1345 cancel_delayed_work_sync(&xadc->zynq_unmask_work); 1346 err_clk_disable_unprepare: 1347 clk_disable_unprepare(xadc->clk); 1348 err_free_samplerate_trigger: 1349 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) 1350 iio_trigger_free(xadc->samplerate_trigger); 1351 err_free_convst_trigger: 1352 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) 1353 iio_trigger_free(xadc->convst_trigger); 1354 err_triggered_buffer_cleanup: 1355 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) 1356 iio_triggered_buffer_cleanup(indio_dev); 1357 err_device_free: 1358 kfree(indio_dev->channels); 1359 1360 return ret; 1361 } 1362 1363 static int xadc_remove(struct platform_device *pdev) 1364 { 1365 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 1366 struct xadc *xadc = iio_priv(indio_dev); 1367 1368 iio_device_unregister(indio_dev); 1369 if (xadc->ops->flags & XADC_FLAGS_BUFFERED) { 1370 iio_trigger_free(xadc->samplerate_trigger); 1371 iio_trigger_free(xadc->convst_trigger); 1372 iio_triggered_buffer_cleanup(indio_dev); 1373 } 1374 free_irq(xadc->irq, indio_dev); 1375 cancel_delayed_work_sync(&xadc->zynq_unmask_work); 1376 clk_disable_unprepare(xadc->clk); 1377 kfree(xadc->data); 1378 kfree(indio_dev->channels); 1379 1380 return 0; 1381 } 1382 1383 static struct platform_driver xadc_driver = { 1384 .probe = xadc_probe, 1385 .remove = xadc_remove, 1386 .driver = { 1387 .name = "xadc", 1388 .of_match_table = xadc_of_match_table, 1389 }, 1390 }; 1391 module_platform_driver(xadc_driver); 1392 1393 MODULE_LICENSE("GPL v2"); 1394 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 1395 MODULE_DESCRIPTION("Xilinx XADC IIO driver"); 1396