1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for the Renesas R-Car I2C unit 4 * 5 * Copyright (C) 2014-19 Wolfram Sang <wsa@sang-engineering.com> 6 * Copyright (C) 2011-2019 Renesas Electronics Corporation 7 * 8 * Copyright (C) 2012-14 Renesas Solutions Corp. 9 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> 10 * 11 * This file is based on the drivers/i2c/busses/i2c-sh7760.c 12 * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com> 13 */ 14 #include <linux/bitops.h> 15 #include <linux/clk.h> 16 #include <linux/delay.h> 17 #include <linux/dmaengine.h> 18 #include <linux/dma-mapping.h> 19 #include <linux/err.h> 20 #include <linux/interrupt.h> 21 #include <linux/io.h> 22 #include <linux/iopoll.h> 23 #include <linux/i2c.h> 24 #include <linux/i2c-smbus.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/of.h> 28 #include <linux/platform_device.h> 29 #include <linux/pm_runtime.h> 30 #include <linux/reset.h> 31 #include <linux/slab.h> 32 33 /* register offsets */ 34 #define ICSCR 0x00 /* slave ctrl */ 35 #define ICMCR 0x04 /* master ctrl */ 36 #define ICSSR 0x08 /* slave status */ 37 #define ICMSR 0x0C /* master status */ 38 #define ICSIER 0x10 /* slave irq enable */ 39 #define ICMIER 0x14 /* master irq enable */ 40 #define ICCCR 0x18 /* clock dividers */ 41 #define ICSAR 0x1C /* slave address */ 42 #define ICMAR 0x20 /* master address */ 43 #define ICRXTX 0x24 /* data port */ 44 #define ICCCR2 0x28 /* Clock control 2 */ 45 #define ICMPR 0x2C /* SCL mask control */ 46 #define ICHPR 0x30 /* SCL HIGH control */ 47 #define ICLPR 0x34 /* SCL LOW control */ 48 #define ICFBSCR 0x38 /* first bit setup cycle (Gen3) */ 49 #define ICDMAER 0x3c /* DMA enable (Gen3) */ 50 51 /* ICSCR */ 52 #define SDBS BIT(3) /* slave data buffer select */ 53 #define SIE BIT(2) /* slave interface enable */ 54 #define GCAE BIT(1) /* general call address enable */ 55 #define FNA BIT(0) /* forced non acknowledgment */ 56 57 /* ICMCR */ 58 #define MDBS BIT(7) /* non-fifo mode switch */ 59 #define FSCL BIT(6) /* override SCL pin */ 60 #define FSDA BIT(5) /* override SDA pin */ 61 #define OBPC BIT(4) /* override pins */ 62 #define MIE BIT(3) /* master if enable */ 63 #define TSBE BIT(2) 64 #define FSB BIT(1) /* force stop bit */ 65 #define ESG BIT(0) /* enable start bit gen */ 66 67 /* ICSSR (also for ICSIER) */ 68 #define GCAR BIT(6) /* general call received */ 69 #define STM BIT(5) /* slave transmit mode */ 70 #define SSR BIT(4) /* stop received */ 71 #define SDE BIT(3) /* slave data empty */ 72 #define SDT BIT(2) /* slave data transmitted */ 73 #define SDR BIT(1) /* slave data received */ 74 #define SAR BIT(0) /* slave addr received */ 75 76 /* ICMSR (also for ICMIE) */ 77 #define MNR BIT(6) /* nack received */ 78 #define MAL BIT(5) /* arbitration lost */ 79 #define MST BIT(4) /* sent a stop */ 80 #define MDE BIT(3) 81 #define MDT BIT(2) 82 #define MDR BIT(1) 83 #define MAT BIT(0) /* slave addr xfer done */ 84 85 /* ICDMAER */ 86 #define RSDMAE BIT(3) /* DMA Slave Received Enable */ 87 #define TSDMAE BIT(2) /* DMA Slave Transmitted Enable */ 88 #define RMDMAE BIT(1) /* DMA Master Received Enable */ 89 #define TMDMAE BIT(0) /* DMA Master Transmitted Enable */ 90 91 /* ICCCR2 */ 92 #define FMPE BIT(7) /* Fast Mode Plus Enable */ 93 #define CDFD BIT(2) /* CDF Disable */ 94 #define HLSE BIT(1) /* HIGH/LOW Separate Control Enable */ 95 #define SME BIT(0) /* SCL Mask Enable */ 96 97 /* ICFBSCR */ 98 #define TCYC17 0x0f /* 17*Tcyc delay 1st bit between SDA and SCL */ 99 100 #define RCAR_MIN_DMA_LEN 8 101 102 /* SCL low/high ratio 5:4 to meet all I2C timing specs (incl safety margin) */ 103 #define RCAR_SCLD_RATIO 5 104 #define RCAR_SCHD_RATIO 4 105 /* 106 * SMD should be smaller than SCLD/SCHD and is always around 20 in the docs. 107 * Thus, we simply use 20 which works for low and high speeds. 108 */ 109 #define RCAR_DEFAULT_SMD 20 110 111 #define RCAR_BUS_PHASE_START (MDBS | MIE | ESG) 112 #define RCAR_BUS_PHASE_DATA (MDBS | MIE) 113 #define RCAR_BUS_PHASE_STOP (MDBS | MIE | FSB) 114 115 #define RCAR_IRQ_SEND (MNR | MAL | MST | MAT | MDE) 116 #define RCAR_IRQ_RECV (MNR | MAL | MST | MAT | MDR) 117 #define RCAR_IRQ_STOP (MST) 118 119 #define ID_LAST_MSG BIT(0) 120 #define ID_REP_AFTER_RD BIT(1) 121 #define ID_DONE BIT(2) 122 #define ID_ARBLOST BIT(3) 123 #define ID_NACK BIT(4) 124 #define ID_EPROTO BIT(5) 125 /* persistent flags */ 126 #define ID_P_FMPLUS BIT(27) 127 #define ID_P_NOT_ATOMIC BIT(28) 128 #define ID_P_HOST_NOTIFY BIT(29) 129 #define ID_P_NO_RXDMA BIT(30) /* HW forbids RXDMA sometimes */ 130 #define ID_P_PM_BLOCKED BIT(31) 131 #define ID_P_MASK GENMASK(31, 27) 132 133 #define ID_SLAVE_NACK BIT(0) 134 135 enum rcar_i2c_type { 136 I2C_RCAR_GEN1, 137 I2C_RCAR_GEN2, 138 I2C_RCAR_GEN3, 139 I2C_RCAR_GEN4, 140 }; 141 142 struct rcar_i2c_priv { 143 u32 flags; 144 void __iomem *io; 145 struct i2c_adapter adap; 146 struct i2c_msg *msg; 147 int msgs_left; 148 struct clk *clk; 149 150 wait_queue_head_t wait; 151 152 int pos; 153 u32 icccr; 154 u16 schd; 155 u16 scld; 156 u8 smd; 157 u8 recovery_icmcr; /* protected by adapter lock */ 158 enum rcar_i2c_type devtype; 159 struct i2c_client *slave; 160 161 struct resource *res; 162 struct dma_chan *dma_tx; 163 struct dma_chan *dma_rx; 164 struct scatterlist sg; 165 enum dma_data_direction dma_direction; 166 167 struct reset_control *rstc; 168 int irq; 169 170 struct i2c_client *host_notify_client; 171 u8 slave_flags; 172 }; 173 174 #define rcar_i2c_priv_to_dev(p) ((p)->adap.dev.parent) 175 #define rcar_i2c_is_recv(p) ((p)->msg->flags & I2C_M_RD) 176 177 static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val) 178 { 179 writel(val, priv->io + reg); 180 } 181 182 static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg) 183 { 184 return readl(priv->io + reg); 185 } 186 187 static void rcar_i2c_clear_irq(struct rcar_i2c_priv *priv, u32 val) 188 { 189 writel(~val & 0x7f, priv->io + ICMSR); 190 } 191 192 static int rcar_i2c_get_scl(struct i2c_adapter *adap) 193 { 194 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 195 196 return !!(rcar_i2c_read(priv, ICMCR) & FSCL); 197 } 198 199 static void rcar_i2c_set_scl(struct i2c_adapter *adap, int val) 200 { 201 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 202 203 if (val) 204 priv->recovery_icmcr |= FSCL; 205 else 206 priv->recovery_icmcr &= ~FSCL; 207 208 rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr); 209 } 210 211 static void rcar_i2c_set_sda(struct i2c_adapter *adap, int val) 212 { 213 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 214 215 if (val) 216 priv->recovery_icmcr |= FSDA; 217 else 218 priv->recovery_icmcr &= ~FSDA; 219 220 rcar_i2c_write(priv, ICMCR, priv->recovery_icmcr); 221 } 222 223 static int rcar_i2c_get_bus_free(struct i2c_adapter *adap) 224 { 225 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 226 227 return !(rcar_i2c_read(priv, ICMCR) & FSDA); 228 } 229 230 static struct i2c_bus_recovery_info rcar_i2c_bri = { 231 .get_scl = rcar_i2c_get_scl, 232 .set_scl = rcar_i2c_set_scl, 233 .set_sda = rcar_i2c_set_sda, 234 .get_bus_free = rcar_i2c_get_bus_free, 235 .recover_bus = i2c_generic_scl_recovery, 236 }; 237 238 static void rcar_i2c_init(struct rcar_i2c_priv *priv) 239 { 240 /* reset master mode */ 241 rcar_i2c_write(priv, ICMIER, 0); 242 rcar_i2c_write(priv, ICMCR, MDBS); 243 rcar_i2c_write(priv, ICMSR, 0); 244 /* start clock */ 245 if (priv->devtype < I2C_RCAR_GEN3) { 246 rcar_i2c_write(priv, ICCCR, priv->icccr); 247 } else { 248 u32 icccr2 = CDFD | HLSE | SME; 249 250 if (priv->flags & ID_P_FMPLUS) 251 icccr2 |= FMPE; 252 253 rcar_i2c_write(priv, ICCCR2, icccr2); 254 rcar_i2c_write(priv, ICCCR, priv->icccr); 255 rcar_i2c_write(priv, ICMPR, priv->smd); 256 rcar_i2c_write(priv, ICHPR, priv->schd); 257 rcar_i2c_write(priv, ICLPR, priv->scld); 258 rcar_i2c_write(priv, ICFBSCR, TCYC17); 259 } 260 } 261 262 static void rcar_i2c_reset_slave(struct rcar_i2c_priv *priv) 263 { 264 rcar_i2c_write(priv, ICSIER, 0); 265 rcar_i2c_write(priv, ICSSR, 0); 266 rcar_i2c_write(priv, ICSCR, SDBS); 267 rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ 268 } 269 270 static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv) 271 { 272 int ret; 273 u32 val; 274 275 ret = readl_poll_timeout(priv->io + ICMCR, val, !(val & FSDA), 10, 276 priv->adap.timeout); 277 if (ret) { 278 /* Waiting did not help, try to recover */ 279 priv->recovery_icmcr = MDBS | OBPC | FSDA | FSCL; 280 ret = i2c_recover_bus(&priv->adap); 281 } 282 283 return ret; 284 } 285 286 static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv) 287 { 288 u32 cdf, round, ick, sum, scl, cdf_width; 289 unsigned long rate; 290 struct device *dev = rcar_i2c_priv_to_dev(priv); 291 struct i2c_timings t = { 292 .bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ, 293 .scl_fall_ns = 35, 294 .scl_rise_ns = 200, 295 .scl_int_delay_ns = 50, 296 }; 297 298 /* Fall back to previously used values if not supplied */ 299 i2c_parse_fw_timings(dev, &t, false); 300 priv->smd = RCAR_DEFAULT_SMD; 301 302 /* 303 * calculate SCL clock 304 * see 305 * ICCCR (and ICCCR2 for Gen3+) 306 * 307 * ick = clkp / (1 + CDF) 308 * SCL = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick]) 309 * 310 * for Gen3+: 311 * SCL = clkp / (8 + SMD * 2 + SCLD + SCHD +F[(ticf + tr + intd) * clkp]) 312 * 313 * ick : I2C internal clock < 20 MHz 314 * ticf : I2C SCL falling time 315 * tr : I2C SCL rising time 316 * intd : LSI internal delay 317 * clkp : peripheral_clk 318 * F[] : integer up-valuation 319 */ 320 rate = clk_get_rate(priv->clk); 321 cdf = rate / 20000000; 322 cdf_width = (priv->devtype == I2C_RCAR_GEN1) ? 2 : 3; 323 if (cdf >= 1U << cdf_width) 324 goto err_no_val; 325 326 if (t.bus_freq_hz > I2C_MAX_FAST_MODE_FREQ && priv->devtype >= I2C_RCAR_GEN4) 327 priv->flags |= ID_P_FMPLUS; 328 else 329 priv->flags &= ~ID_P_FMPLUS; 330 331 /* On Gen3+, we use cdf only for the filters, not as a SCL divider */ 332 ick = rate / (priv->devtype < I2C_RCAR_GEN3 ? (cdf + 1) : 1); 333 334 /* 335 * It is impossible to calculate a large scale number on u32. Separate it. 336 * 337 * F[(ticf + tr + intd) * ick] with sum = (ticf + tr + intd) 338 * = F[sum * ick / 1000000000] 339 * = F[(ick / 1000000) * sum / 1000] 340 */ 341 sum = t.scl_fall_ns + t.scl_rise_ns + t.scl_int_delay_ns; 342 round = DIV_ROUND_CLOSEST(ick, 1000000); 343 round = DIV_ROUND_CLOSEST(round * sum, 1000); 344 345 if (priv->devtype < I2C_RCAR_GEN3) { 346 u32 scgd; 347 /* 348 * SCL = ick / (20 + 8 * SCGD + F[(ticf + tr + intd) * ick]) 349 * 20 + 8 * SCGD + F[...] = ick / SCL 350 * SCGD = ((ick / SCL) - 20 - F[...]) / 8 351 * Result (= SCL) should be less than bus_speed for hardware safety 352 */ 353 scgd = DIV_ROUND_UP(ick, t.bus_freq_hz ?: 1); 354 scgd = DIV_ROUND_UP(scgd - 20 - round, 8); 355 scl = ick / (20 + 8 * scgd + round); 356 357 if (scgd > 0x3f) 358 goto err_no_val; 359 360 dev_dbg(dev, "clk %u/%u(%lu), round %u, CDF: %u, SCGD: %u\n", 361 scl, t.bus_freq_hz, rate, round, cdf, scgd); 362 363 priv->icccr = scgd << cdf_width | cdf; 364 } else { 365 u32 x, sum_ratio = RCAR_SCHD_RATIO + RCAR_SCLD_RATIO; 366 /* 367 * SCLD/SCHD ratio and SMD default value are explained above 368 * where they are defined. With these definitions, we can compute 369 * x as a base value for the SCLD/SCHD ratio: 370 * 371 * SCL = clkp / (8 + 2 * SMD + SCLD + SCHD + F[(ticf + tr + intd) * clkp]) 372 * SCL = clkp / (8 + 2 * SMD + RCAR_SCLD_RATIO * x 373 * + RCAR_SCHD_RATIO * x + F[...]) 374 * 375 * with: sum_ratio = RCAR_SCLD_RATIO + RCAR_SCHD_RATIO 376 * 377 * SCL = clkp / (8 + 2 * smd + sum_ratio * x + F[...]) 378 * 8 + 2 * smd + sum_ratio * x + F[...] = clkp / SCL 379 * x = ((clkp / SCL) - 8 - 2 * smd - F[...]) / sum_ratio 380 */ 381 x = DIV_ROUND_UP(rate, t.bus_freq_hz ?: 1); 382 x = DIV_ROUND_UP(x - 8 - 2 * priv->smd - round, sum_ratio); 383 scl = rate / (8 + 2 * priv->smd + sum_ratio * x + round); 384 385 if (x == 0 || x * RCAR_SCLD_RATIO > 0xffff) 386 goto err_no_val; 387 388 priv->icccr = cdf; 389 priv->schd = RCAR_SCHD_RATIO * x; 390 priv->scld = RCAR_SCLD_RATIO * x; 391 if (priv->smd >= priv->schd) 392 priv->smd = priv->schd - 1; 393 394 dev_dbg(dev, "clk %u/%u(%lu), round %u, CDF: %u SCHD %u SCLD %u SMD %u\n", 395 scl, t.bus_freq_hz, rate, round, cdf, priv->schd, priv->scld, priv->smd); 396 } 397 398 return 0; 399 400 err_no_val: 401 dev_err(dev, "it is impossible to calculate best SCL\n"); 402 return -EINVAL; 403 } 404 405 /* 406 * We don't have a test case but the HW engineers say that the write order of 407 * ICMSR and ICMCR depends on whether we issue START or REP_START. So, ICMSR 408 * handling is outside of this function. First messages clear ICMSR before this 409 * function, interrupt handlers clear the relevant bits after this function. 410 */ 411 static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv) 412 { 413 int read = !!rcar_i2c_is_recv(priv); 414 bool rep_start = !(priv->flags & ID_REP_AFTER_RD); 415 416 priv->pos = 0; 417 priv->flags &= ID_P_MASK; 418 419 if (priv->msgs_left == 1) 420 priv->flags |= ID_LAST_MSG; 421 422 rcar_i2c_write(priv, ICMAR, i2c_8bit_addr_from_msg(priv->msg)); 423 if (priv->flags & ID_P_NOT_ATOMIC) 424 rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND); 425 426 if (rep_start) 427 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START); 428 } 429 430 static void rcar_i2c_first_msg(struct rcar_i2c_priv *priv, 431 struct i2c_msg *msgs, int num) 432 { 433 priv->msg = msgs; 434 priv->msgs_left = num; 435 rcar_i2c_write(priv, ICMSR, 0); /* must be before preparing msg */ 436 rcar_i2c_prepare_msg(priv); 437 } 438 439 static void rcar_i2c_next_msg(struct rcar_i2c_priv *priv) 440 { 441 priv->msg++; 442 priv->msgs_left--; 443 rcar_i2c_prepare_msg(priv); 444 /* ICMSR handling must come afterwards in the irq handler */ 445 } 446 447 static void rcar_i2c_cleanup_dma(struct rcar_i2c_priv *priv, bool terminate) 448 { 449 struct dma_chan *chan = priv->dma_direction == DMA_FROM_DEVICE 450 ? priv->dma_rx : priv->dma_tx; 451 452 /* only allowed from thread context! */ 453 if (terminate) 454 dmaengine_terminate_sync(chan); 455 456 dma_unmap_single(chan->device->dev, sg_dma_address(&priv->sg), 457 sg_dma_len(&priv->sg), priv->dma_direction); 458 459 /* Gen3+ can only do one RXDMA per transfer and we just completed it */ 460 if (priv->devtype >= I2C_RCAR_GEN3 && 461 priv->dma_direction == DMA_FROM_DEVICE) 462 priv->flags |= ID_P_NO_RXDMA; 463 464 priv->dma_direction = DMA_NONE; 465 466 /* Disable DMA Master Received/Transmitted, must be last! */ 467 rcar_i2c_write(priv, ICDMAER, 0); 468 } 469 470 static void rcar_i2c_dma_callback(void *data) 471 { 472 struct rcar_i2c_priv *priv = data; 473 474 priv->pos += sg_dma_len(&priv->sg); 475 476 rcar_i2c_cleanup_dma(priv, false); 477 } 478 479 static bool rcar_i2c_dma(struct rcar_i2c_priv *priv) 480 { 481 struct device *dev = rcar_i2c_priv_to_dev(priv); 482 struct i2c_msg *msg = priv->msg; 483 bool read = msg->flags & I2C_M_RD; 484 enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 485 struct dma_chan *chan = read ? priv->dma_rx : priv->dma_tx; 486 struct dma_async_tx_descriptor *txdesc; 487 dma_addr_t dma_addr; 488 dma_cookie_t cookie; 489 unsigned char *buf; 490 int len; 491 492 /* Do various checks to see if DMA is feasible at all */ 493 if (!(priv->flags & ID_P_NOT_ATOMIC) || IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN || 494 !(msg->flags & I2C_M_DMA_SAFE) || (read && priv->flags & ID_P_NO_RXDMA)) 495 return false; 496 497 if (read) { 498 /* 499 * The last two bytes needs to be fetched using PIO in 500 * order for the STOP phase to work. 501 */ 502 buf = priv->msg->buf; 503 len = priv->msg->len - 2; 504 } else { 505 /* 506 * First byte in message was sent using PIO. 507 */ 508 buf = priv->msg->buf + 1; 509 len = priv->msg->len - 1; 510 } 511 512 dma_addr = dma_map_single(chan->device->dev, buf, len, dir); 513 if (dma_mapping_error(chan->device->dev, dma_addr)) { 514 dev_dbg(dev, "dma map failed, using PIO\n"); 515 return false; 516 } 517 518 sg_dma_len(&priv->sg) = len; 519 sg_dma_address(&priv->sg) = dma_addr; 520 521 priv->dma_direction = dir; 522 523 txdesc = dmaengine_prep_slave_sg(chan, &priv->sg, 1, 524 read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV, 525 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 526 if (!txdesc) { 527 dev_dbg(dev, "dma prep slave sg failed, using PIO\n"); 528 rcar_i2c_cleanup_dma(priv, false); 529 return false; 530 } 531 532 txdesc->callback = rcar_i2c_dma_callback; 533 txdesc->callback_param = priv; 534 535 cookie = dmaengine_submit(txdesc); 536 if (dma_submit_error(cookie)) { 537 dev_dbg(dev, "submitting dma failed, using PIO\n"); 538 rcar_i2c_cleanup_dma(priv, false); 539 return false; 540 } 541 542 /* Enable DMA Master Received/Transmitted */ 543 if (read) 544 rcar_i2c_write(priv, ICDMAER, RMDMAE); 545 else 546 rcar_i2c_write(priv, ICDMAER, TMDMAE); 547 548 dma_async_issue_pending(chan); 549 return true; 550 } 551 552 static void rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr) 553 { 554 struct i2c_msg *msg = priv->msg; 555 u32 irqs_to_clear = MDE; 556 557 /* FIXME: sometimes, unknown interrupt happened. Do nothing */ 558 if (WARN(!(msr & MDE), "spurious irq")) 559 return; 560 561 if (msr & MAT) 562 irqs_to_clear |= MAT; 563 564 /* Check if DMA can be enabled and take over */ 565 if (priv->pos == 1 && rcar_i2c_dma(priv)) 566 return; 567 568 if (priv->pos < msg->len) { 569 /* 570 * Prepare next data to ICRXTX register. 571 * This data will go to _SHIFT_ register. 572 * 573 * * 574 * [ICRXTX] -> [SHIFT] -> [I2C bus] 575 */ 576 rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]); 577 priv->pos++; 578 } else { 579 /* 580 * The last data was pushed to ICRXTX on _PREV_ empty irq. 581 * It is on _SHIFT_ register, and will sent to I2C bus. 582 * 583 * * 584 * [ICRXTX] -> [SHIFT] -> [I2C bus] 585 */ 586 587 if (priv->flags & ID_LAST_MSG) 588 /* 589 * If current msg is the _LAST_ msg, 590 * prepare stop condition here. 591 * ID_DONE will be set on STOP irq. 592 */ 593 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP); 594 else 595 rcar_i2c_next_msg(priv); 596 } 597 598 rcar_i2c_clear_irq(priv, irqs_to_clear); 599 } 600 601 static void rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr) 602 { 603 struct i2c_msg *msg = priv->msg; 604 bool recv_len_init = priv->pos == 0 && msg->flags & I2C_M_RECV_LEN; 605 u32 irqs_to_clear = MDR; 606 607 /* FIXME: sometimes, unknown interrupt happened. Do nothing */ 608 if (!(msr & MDR)) 609 return; 610 611 if (msr & MAT) { 612 irqs_to_clear |= MAT; 613 /* 614 * Address transfer phase finished, but no data at this point. 615 * Try to use DMA to receive data. 616 */ 617 rcar_i2c_dma(priv); 618 } else if (priv->pos < msg->len) { 619 /* get received data */ 620 u8 data = rcar_i2c_read(priv, ICRXTX); 621 622 msg->buf[priv->pos] = data; 623 if (recv_len_init) { 624 if (data == 0 || data > I2C_SMBUS_BLOCK_MAX) { 625 priv->flags |= ID_DONE | ID_EPROTO; 626 return; 627 } 628 msg->len += msg->buf[0]; 629 /* Enough data for DMA? */ 630 if (rcar_i2c_dma(priv)) 631 return; 632 /* new length after RECV_LEN now properly initialized */ 633 recv_len_init = false; 634 } 635 priv->pos++; 636 } 637 638 /* 639 * If next received data is the _LAST_ and we are not waiting for a new 640 * length because of RECV_LEN, then go to a new phase. 641 */ 642 if (priv->pos + 1 == msg->len && !recv_len_init) { 643 if (priv->flags & ID_LAST_MSG) { 644 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP); 645 } else { 646 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START); 647 priv->flags |= ID_REP_AFTER_RD; 648 } 649 } 650 651 if (priv->pos == msg->len && !(priv->flags & ID_LAST_MSG)) 652 rcar_i2c_next_msg(priv); 653 654 rcar_i2c_clear_irq(priv, irqs_to_clear); 655 } 656 657 static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv) 658 { 659 u32 ssr_raw, ssr_filtered; 660 u8 value; 661 int ret; 662 663 ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff; 664 ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER); 665 666 if (!ssr_filtered) 667 return false; 668 669 /* address detected */ 670 if (ssr_filtered & SAR) { 671 /* read or write request */ 672 if (ssr_raw & STM) { 673 i2c_slave_event(priv->slave, I2C_SLAVE_READ_REQUESTED, &value); 674 rcar_i2c_write(priv, ICRXTX, value); 675 rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR); 676 } else { 677 ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value); 678 if (ret) 679 priv->slave_flags |= ID_SLAVE_NACK; 680 681 rcar_i2c_read(priv, ICRXTX); /* dummy read */ 682 rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR); 683 } 684 685 /* Clear SSR, too, because of old STOPs to other clients than us */ 686 rcar_i2c_write(priv, ICSSR, ~(SAR | SSR) & 0xff); 687 } 688 689 /* master sent stop */ 690 if (ssr_filtered & SSR) { 691 i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value); 692 rcar_i2c_write(priv, ICSCR, SIE | SDBS); /* clear our NACK */ 693 priv->slave_flags &= ~ID_SLAVE_NACK; 694 rcar_i2c_write(priv, ICSIER, SAR); 695 rcar_i2c_write(priv, ICSSR, ~SSR & 0xff); 696 } 697 698 /* master wants to write to us */ 699 if (ssr_filtered & SDR) { 700 value = rcar_i2c_read(priv, ICRXTX); 701 ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value); 702 if (ret) 703 priv->slave_flags |= ID_SLAVE_NACK; 704 705 /* Send NACK in case of error, but it will come 1 byte late :( */ 706 rcar_i2c_write(priv, ICSCR, SIE | SDBS | 707 (priv->slave_flags & ID_SLAVE_NACK ? FNA : 0)); 708 rcar_i2c_write(priv, ICSSR, ~SDR & 0xff); 709 } 710 711 /* master wants to read from us */ 712 if (ssr_filtered & SDE) { 713 i2c_slave_event(priv->slave, I2C_SLAVE_READ_PROCESSED, &value); 714 rcar_i2c_write(priv, ICRXTX, value); 715 rcar_i2c_write(priv, ICSSR, ~SDE & 0xff); 716 } 717 718 return true; 719 } 720 721 /* 722 * This driver has a lock-free design because there are IP cores (at least 723 * R-Car Gen2) which have an inherent race condition in their hardware design. 724 * There, we need to switch to RCAR_BUS_PHASE_DATA as soon as possible after 725 * the interrupt was generated, otherwise an unwanted repeated message gets 726 * generated. It turned out that taking a spinlock at the beginning of the ISR 727 * was already causing repeated messages. Thus, this driver was converted to 728 * the now lockless behaviour. Please keep this in mind when hacking the driver. 729 * R-Car Gen3 seems to have this fixed but earlier versions than R-Car Gen2 are 730 * likely affected. Therefore, we have different interrupt handler entries. 731 */ 732 static irqreturn_t rcar_i2c_irq(int irq, struct rcar_i2c_priv *priv, u32 msr) 733 { 734 if (!msr) { 735 if (rcar_i2c_slave_irq(priv)) 736 return IRQ_HANDLED; 737 738 return IRQ_NONE; 739 } 740 741 /* Arbitration lost */ 742 if (msr & MAL) { 743 priv->flags |= ID_DONE | ID_ARBLOST; 744 goto out; 745 } 746 747 /* Nack */ 748 if (msr & MNR) { 749 /* HW automatically sends STOP after received NACK */ 750 if (priv->flags & ID_P_NOT_ATOMIC) 751 rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP); 752 priv->flags |= ID_NACK; 753 goto out; 754 } 755 756 /* Stop */ 757 if (msr & MST) { 758 priv->msgs_left--; /* The last message also made it */ 759 priv->flags |= ID_DONE; 760 goto out; 761 } 762 763 if (rcar_i2c_is_recv(priv)) 764 rcar_i2c_irq_recv(priv, msr); 765 else 766 rcar_i2c_irq_send(priv, msr); 767 768 out: 769 if (priv->flags & ID_DONE) { 770 rcar_i2c_write(priv, ICMIER, 0); 771 rcar_i2c_write(priv, ICMSR, 0); 772 if (priv->flags & ID_P_NOT_ATOMIC) 773 wake_up(&priv->wait); 774 } 775 776 return IRQ_HANDLED; 777 } 778 779 static irqreturn_t rcar_i2c_gen2_irq(int irq, void *ptr) 780 { 781 struct rcar_i2c_priv *priv = ptr; 782 u32 msr; 783 784 /* Clear START or STOP immediately, except for REPSTART after read */ 785 if (likely(!(priv->flags & ID_REP_AFTER_RD))) 786 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA); 787 788 /* Only handle interrupts that are currently enabled */ 789 msr = rcar_i2c_read(priv, ICMSR); 790 if (priv->flags & ID_P_NOT_ATOMIC) 791 msr &= rcar_i2c_read(priv, ICMIER); 792 793 return rcar_i2c_irq(irq, priv, msr); 794 } 795 796 static irqreturn_t rcar_i2c_gen3_irq(int irq, void *ptr) 797 { 798 struct rcar_i2c_priv *priv = ptr; 799 u32 msr; 800 801 /* Only handle interrupts that are currently enabled */ 802 msr = rcar_i2c_read(priv, ICMSR); 803 if (priv->flags & ID_P_NOT_ATOMIC) 804 msr &= rcar_i2c_read(priv, ICMIER); 805 806 /* 807 * Clear START or STOP immediately, except for REPSTART after read or 808 * if a spurious interrupt was detected. 809 */ 810 if (likely(!(priv->flags & ID_REP_AFTER_RD) && msr)) 811 rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA); 812 813 return rcar_i2c_irq(irq, priv, msr); 814 } 815 816 static struct dma_chan *rcar_i2c_request_dma_chan(struct device *dev, 817 enum dma_transfer_direction dir, 818 dma_addr_t port_addr) 819 { 820 struct dma_chan *chan; 821 struct dma_slave_config cfg; 822 char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx"; 823 int ret; 824 825 chan = dma_request_chan(dev, chan_name); 826 if (IS_ERR(chan)) { 827 dev_dbg(dev, "request_channel failed for %s (%ld)\n", 828 chan_name, PTR_ERR(chan)); 829 return chan; 830 } 831 832 memset(&cfg, 0, sizeof(cfg)); 833 cfg.direction = dir; 834 if (dir == DMA_MEM_TO_DEV) { 835 cfg.dst_addr = port_addr; 836 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 837 } else { 838 cfg.src_addr = port_addr; 839 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 840 } 841 842 ret = dmaengine_slave_config(chan, &cfg); 843 if (ret) { 844 dev_dbg(dev, "slave_config failed for %s (%d)\n", 845 chan_name, ret); 846 dma_release_channel(chan); 847 return ERR_PTR(ret); 848 } 849 850 dev_dbg(dev, "got DMA channel for %s\n", chan_name); 851 return chan; 852 } 853 854 static void rcar_i2c_request_dma(struct rcar_i2c_priv *priv, 855 struct i2c_msg *msg) 856 { 857 struct device *dev = rcar_i2c_priv_to_dev(priv); 858 bool read; 859 struct dma_chan *chan; 860 enum dma_transfer_direction dir; 861 862 read = msg->flags & I2C_M_RD; 863 864 chan = read ? priv->dma_rx : priv->dma_tx; 865 if (PTR_ERR(chan) != -EPROBE_DEFER) 866 return; 867 868 dir = read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; 869 chan = rcar_i2c_request_dma_chan(dev, dir, priv->res->start + ICRXTX); 870 871 if (read) 872 priv->dma_rx = chan; 873 else 874 priv->dma_tx = chan; 875 } 876 877 static void rcar_i2c_release_dma(struct rcar_i2c_priv *priv) 878 { 879 if (!IS_ERR(priv->dma_tx)) { 880 dma_release_channel(priv->dma_tx); 881 priv->dma_tx = ERR_PTR(-EPROBE_DEFER); 882 } 883 884 if (!IS_ERR(priv->dma_rx)) { 885 dma_release_channel(priv->dma_rx); 886 priv->dma_rx = ERR_PTR(-EPROBE_DEFER); 887 } 888 } 889 890 /* I2C is a special case, we need to poll the status of a reset */ 891 static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv) 892 { 893 int ret; 894 895 /* Don't reset if a slave instance is currently running */ 896 if (priv->slave) 897 return -EISCONN; 898 899 ret = reset_control_reset(priv->rstc); 900 if (ret) 901 return ret; 902 903 return read_poll_timeout_atomic(reset_control_status, ret, ret == 0, 1, 904 100, false, priv->rstc); 905 } 906 907 static int rcar_i2c_master_xfer(struct i2c_adapter *adap, 908 struct i2c_msg *msgs, 909 int num) 910 { 911 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 912 struct device *dev = rcar_i2c_priv_to_dev(priv); 913 int i, ret; 914 long time_left; 915 916 priv->flags |= ID_P_NOT_ATOMIC; 917 918 pm_runtime_get_sync(dev); 919 920 /* Check bus state before init otherwise bus busy info will be lost */ 921 ret = rcar_i2c_bus_barrier(priv); 922 if (ret < 0) 923 goto out; 924 925 /* Gen3+ needs a reset. That also allows RXDMA once */ 926 if (priv->devtype >= I2C_RCAR_GEN3) { 927 ret = rcar_i2c_do_reset(priv); 928 if (ret) 929 goto out; 930 priv->flags &= ~ID_P_NO_RXDMA; 931 } 932 933 rcar_i2c_init(priv); 934 935 for (i = 0; i < num; i++) 936 rcar_i2c_request_dma(priv, msgs + i); 937 938 rcar_i2c_first_msg(priv, msgs, num); 939 940 time_left = wait_event_timeout(priv->wait, priv->flags & ID_DONE, 941 num * adap->timeout); 942 943 /* cleanup DMA if it couldn't complete properly due to an error */ 944 if (priv->dma_direction != DMA_NONE) 945 rcar_i2c_cleanup_dma(priv, true); 946 947 if (!time_left) { 948 rcar_i2c_init(priv); 949 ret = -ETIMEDOUT; 950 } else if (priv->flags & ID_NACK) { 951 ret = -ENXIO; 952 } else if (priv->flags & ID_ARBLOST) { 953 ret = -EAGAIN; 954 } else if (priv->flags & ID_EPROTO) { 955 ret = -EPROTO; 956 } else { 957 ret = num - priv->msgs_left; /* The number of transfer */ 958 } 959 out: 960 pm_runtime_put(dev); 961 962 if (ret < 0 && ret != -ENXIO) 963 dev_err(dev, "error %d : %x\n", ret, priv->flags); 964 965 return ret; 966 } 967 968 static int rcar_i2c_master_xfer_atomic(struct i2c_adapter *adap, 969 struct i2c_msg *msgs, 970 int num) 971 { 972 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 973 struct device *dev = rcar_i2c_priv_to_dev(priv); 974 unsigned long j; 975 bool time_left; 976 int ret; 977 978 priv->flags &= ~ID_P_NOT_ATOMIC; 979 980 pm_runtime_get_sync(dev); 981 982 /* Check bus state before init otherwise bus busy info will be lost */ 983 ret = rcar_i2c_bus_barrier(priv); 984 if (ret < 0) 985 goto out; 986 987 rcar_i2c_init(priv); 988 rcar_i2c_first_msg(priv, msgs, num); 989 990 j = jiffies + num * adap->timeout; 991 do { 992 u32 msr = rcar_i2c_read(priv, ICMSR); 993 994 msr &= (rcar_i2c_is_recv(priv) ? RCAR_IRQ_RECV : RCAR_IRQ_SEND) | RCAR_IRQ_STOP; 995 996 if (msr) { 997 if (priv->devtype < I2C_RCAR_GEN3) 998 rcar_i2c_gen2_irq(0, priv); 999 else 1000 rcar_i2c_gen3_irq(0, priv); 1001 } 1002 1003 time_left = time_before_eq(jiffies, j); 1004 } while (!(priv->flags & ID_DONE) && time_left); 1005 1006 if (!time_left) { 1007 rcar_i2c_init(priv); 1008 ret = -ETIMEDOUT; 1009 } else if (priv->flags & ID_NACK) { 1010 ret = -ENXIO; 1011 } else if (priv->flags & ID_ARBLOST) { 1012 ret = -EAGAIN; 1013 } else if (priv->flags & ID_EPROTO) { 1014 ret = -EPROTO; 1015 } else { 1016 ret = num - priv->msgs_left; /* The number of transfer */ 1017 } 1018 out: 1019 pm_runtime_put(dev); 1020 1021 if (ret < 0 && ret != -ENXIO) 1022 dev_err(dev, "error %d : %x\n", ret, priv->flags); 1023 1024 return ret; 1025 } 1026 1027 static int rcar_reg_slave(struct i2c_client *slave) 1028 { 1029 struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter); 1030 1031 if (priv->slave) 1032 return -EBUSY; 1033 1034 if (slave->flags & I2C_CLIENT_TEN) 1035 return -EAFNOSUPPORT; 1036 1037 /* Keep device active for slave address detection logic */ 1038 pm_runtime_get_sync(rcar_i2c_priv_to_dev(priv)); 1039 1040 priv->slave = slave; 1041 rcar_i2c_write(priv, ICSAR, slave->addr); 1042 rcar_i2c_write(priv, ICSSR, 0); 1043 rcar_i2c_write(priv, ICSIER, SAR); 1044 rcar_i2c_write(priv, ICSCR, SIE | SDBS); 1045 1046 return 0; 1047 } 1048 1049 static int rcar_unreg_slave(struct i2c_client *slave) 1050 { 1051 struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter); 1052 1053 WARN_ON(!priv->slave); 1054 1055 /* ensure no irq is running before clearing ptr */ 1056 disable_irq(priv->irq); 1057 rcar_i2c_reset_slave(priv); 1058 enable_irq(priv->irq); 1059 1060 priv->slave = NULL; 1061 1062 pm_runtime_put(rcar_i2c_priv_to_dev(priv)); 1063 1064 return 0; 1065 } 1066 1067 static u32 rcar_i2c_func(struct i2c_adapter *adap) 1068 { 1069 struct rcar_i2c_priv *priv = i2c_get_adapdata(adap); 1070 1071 /* 1072 * This HW can't do: 1073 * I2C_SMBUS_QUICK (setting FSB during START didn't work) 1074 * I2C_M_NOSTART (automatically sends address after START) 1075 * I2C_M_IGNORE_NAK (automatically sends STOP after NAK) 1076 */ 1077 u32 func = I2C_FUNC_I2C | I2C_FUNC_SLAVE | 1078 (I2C_FUNC_SMBUS_EMUL_ALL & ~I2C_FUNC_SMBUS_QUICK); 1079 1080 if (priv->flags & ID_P_HOST_NOTIFY) 1081 func |= I2C_FUNC_SMBUS_HOST_NOTIFY; 1082 1083 return func; 1084 } 1085 1086 static const struct i2c_algorithm rcar_i2c_algo = { 1087 .master_xfer = rcar_i2c_master_xfer, 1088 .master_xfer_atomic = rcar_i2c_master_xfer_atomic, 1089 .functionality = rcar_i2c_func, 1090 .reg_slave = rcar_reg_slave, 1091 .unreg_slave = rcar_unreg_slave, 1092 }; 1093 1094 static const struct i2c_adapter_quirks rcar_i2c_quirks = { 1095 .flags = I2C_AQ_NO_ZERO_LEN, 1096 }; 1097 1098 static const struct of_device_id rcar_i2c_dt_ids[] = { 1099 { .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 }, 1100 { .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 }, 1101 { .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 }, 1102 { .compatible = "renesas,i2c-r8a7791", .data = (void *)I2C_RCAR_GEN2 }, 1103 { .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 }, 1104 { .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 }, 1105 { .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 }, 1106 { .compatible = "renesas,i2c-r8a7795", .data = (void *)I2C_RCAR_GEN3 }, 1107 { .compatible = "renesas,i2c-r8a7796", .data = (void *)I2C_RCAR_GEN3 }, 1108 /* S4 has no FM+ bit */ 1109 { .compatible = "renesas,i2c-r8a779f0", .data = (void *)I2C_RCAR_GEN3 }, 1110 { .compatible = "renesas,rcar-gen1-i2c", .data = (void *)I2C_RCAR_GEN1 }, 1111 { .compatible = "renesas,rcar-gen2-i2c", .data = (void *)I2C_RCAR_GEN2 }, 1112 { .compatible = "renesas,rcar-gen3-i2c", .data = (void *)I2C_RCAR_GEN3 }, 1113 { .compatible = "renesas,rcar-gen4-i2c", .data = (void *)I2C_RCAR_GEN4 }, 1114 {}, 1115 }; 1116 MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids); 1117 1118 static int rcar_i2c_probe(struct platform_device *pdev) 1119 { 1120 struct rcar_i2c_priv *priv; 1121 struct i2c_adapter *adap; 1122 struct device *dev = &pdev->dev; 1123 unsigned long irqflags = 0; 1124 irqreturn_t (*irqhandler)(int irq, void *ptr) = rcar_i2c_gen3_irq; 1125 int ret; 1126 1127 /* Otherwise logic will break because some bytes must always use PIO */ 1128 BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length"); 1129 1130 priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL); 1131 if (!priv) 1132 return -ENOMEM; 1133 1134 priv->clk = devm_clk_get(dev, NULL); 1135 if (IS_ERR(priv->clk)) { 1136 dev_err(dev, "cannot get clock\n"); 1137 return PTR_ERR(priv->clk); 1138 } 1139 1140 priv->io = devm_platform_get_and_ioremap_resource(pdev, 0, &priv->res); 1141 if (IS_ERR(priv->io)) 1142 return PTR_ERR(priv->io); 1143 1144 priv->devtype = (enum rcar_i2c_type)of_device_get_match_data(dev); 1145 init_waitqueue_head(&priv->wait); 1146 1147 adap = &priv->adap; 1148 adap->nr = pdev->id; 1149 adap->algo = &rcar_i2c_algo; 1150 adap->class = I2C_CLASS_DEPRECATED; 1151 adap->retries = 3; 1152 adap->dev.parent = dev; 1153 adap->dev.of_node = dev->of_node; 1154 adap->bus_recovery_info = &rcar_i2c_bri; 1155 adap->quirks = &rcar_i2c_quirks; 1156 i2c_set_adapdata(adap, priv); 1157 strscpy(adap->name, pdev->name, sizeof(adap->name)); 1158 1159 /* Init DMA */ 1160 sg_init_table(&priv->sg, 1); 1161 priv->dma_direction = DMA_NONE; 1162 priv->dma_rx = priv->dma_tx = ERR_PTR(-EPROBE_DEFER); 1163 1164 /* Activate device for clock calculation */ 1165 pm_runtime_enable(dev); 1166 pm_runtime_get_sync(dev); 1167 ret = rcar_i2c_clock_calculate(priv); 1168 if (ret < 0) { 1169 pm_runtime_put(dev); 1170 goto out_pm_disable; 1171 } 1172 1173 /* Bring hardware to known state */ 1174 rcar_i2c_init(priv); 1175 rcar_i2c_reset_slave(priv); 1176 1177 /* Stay always active when multi-master to keep arbitration working */ 1178 if (of_property_read_bool(dev->of_node, "multi-master")) 1179 priv->flags |= ID_P_PM_BLOCKED; 1180 else 1181 pm_runtime_put(dev); 1182 1183 if (of_property_read_bool(dev->of_node, "smbus")) 1184 priv->flags |= ID_P_HOST_NOTIFY; 1185 1186 if (priv->devtype < I2C_RCAR_GEN3) { 1187 irqflags |= IRQF_NO_THREAD; 1188 irqhandler = rcar_i2c_gen2_irq; 1189 } else { 1190 /* R-Car Gen3+ needs a reset before every transfer */ 1191 priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); 1192 if (IS_ERR(priv->rstc)) { 1193 ret = PTR_ERR(priv->rstc); 1194 goto out_pm_put; 1195 } 1196 1197 ret = reset_control_status(priv->rstc); 1198 if (ret < 0) 1199 goto out_pm_put; 1200 1201 /* hard reset disturbs HostNotify local target, so disable it */ 1202 priv->flags &= ~ID_P_HOST_NOTIFY; 1203 } 1204 1205 ret = platform_get_irq(pdev, 0); 1206 if (ret < 0) 1207 goto out_pm_put; 1208 priv->irq = ret; 1209 ret = devm_request_irq(dev, priv->irq, irqhandler, irqflags, dev_name(dev), priv); 1210 if (ret < 0) { 1211 dev_err(dev, "cannot get irq %d\n", priv->irq); 1212 goto out_pm_put; 1213 } 1214 1215 platform_set_drvdata(pdev, priv); 1216 1217 ret = i2c_add_numbered_adapter(adap); 1218 if (ret < 0) 1219 goto out_pm_put; 1220 1221 if (priv->flags & ID_P_HOST_NOTIFY) { 1222 priv->host_notify_client = i2c_new_slave_host_notify_device(adap); 1223 if (IS_ERR(priv->host_notify_client)) { 1224 ret = PTR_ERR(priv->host_notify_client); 1225 goto out_del_device; 1226 } 1227 } 1228 1229 dev_info(dev, "probed\n"); 1230 1231 return 0; 1232 1233 out_del_device: 1234 i2c_del_adapter(&priv->adap); 1235 out_pm_put: 1236 if (priv->flags & ID_P_PM_BLOCKED) 1237 pm_runtime_put(dev); 1238 out_pm_disable: 1239 pm_runtime_disable(dev); 1240 return ret; 1241 } 1242 1243 static void rcar_i2c_remove(struct platform_device *pdev) 1244 { 1245 struct rcar_i2c_priv *priv = platform_get_drvdata(pdev); 1246 struct device *dev = &pdev->dev; 1247 1248 if (priv->host_notify_client) 1249 i2c_free_slave_host_notify_device(priv->host_notify_client); 1250 i2c_del_adapter(&priv->adap); 1251 rcar_i2c_release_dma(priv); 1252 if (priv->flags & ID_P_PM_BLOCKED) 1253 pm_runtime_put(dev); 1254 pm_runtime_disable(dev); 1255 } 1256 1257 static int rcar_i2c_suspend(struct device *dev) 1258 { 1259 struct rcar_i2c_priv *priv = dev_get_drvdata(dev); 1260 1261 i2c_mark_adapter_suspended(&priv->adap); 1262 return 0; 1263 } 1264 1265 static int rcar_i2c_resume(struct device *dev) 1266 { 1267 struct rcar_i2c_priv *priv = dev_get_drvdata(dev); 1268 1269 i2c_mark_adapter_resumed(&priv->adap); 1270 return 0; 1271 } 1272 1273 static const struct dev_pm_ops rcar_i2c_pm_ops = { 1274 NOIRQ_SYSTEM_SLEEP_PM_OPS(rcar_i2c_suspend, rcar_i2c_resume) 1275 }; 1276 1277 static struct platform_driver rcar_i2c_driver = { 1278 .driver = { 1279 .name = "i2c-rcar", 1280 .of_match_table = rcar_i2c_dt_ids, 1281 .pm = pm_sleep_ptr(&rcar_i2c_pm_ops), 1282 }, 1283 .probe = rcar_i2c_probe, 1284 .remove = rcar_i2c_remove, 1285 }; 1286 1287 module_platform_driver(rcar_i2c_driver); 1288 1289 MODULE_LICENSE("GPL v2"); 1290 MODULE_DESCRIPTION("Renesas R-Car I2C bus driver"); 1291 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>"); 1292