1 /* 2 * Copyright (C) 2017 Spreadtrum Communications Inc. 3 * 4 * SPDX-License-Identifier: (GPL-2.0+ OR MIT) 5 */ 6 7 #include <linux/clk.h> 8 #include <linux/delay.h> 9 #include <linux/err.h> 10 #include <linux/io.h> 11 #include <linux/i2c.h> 12 #include <linux/init.h> 13 #include <linux/interrupt.h> 14 #include <linux/kernel.h> 15 #include <linux/of.h> 16 #include <linux/of_device.h> 17 #include <linux/platform_device.h> 18 #include <linux/pm_runtime.h> 19 20 #define I2C_CTL 0x00 21 #define I2C_ADDR_CFG 0x04 22 #define I2C_COUNT 0x08 23 #define I2C_RX 0x0c 24 #define I2C_TX 0x10 25 #define I2C_STATUS 0x14 26 #define I2C_HSMODE_CFG 0x18 27 #define I2C_VERSION 0x1c 28 #define ADDR_DVD0 0x20 29 #define ADDR_DVD1 0x24 30 #define ADDR_STA0_DVD 0x28 31 #define ADDR_RST 0x2c 32 33 /* I2C_CTL */ 34 #define STP_EN BIT(20) 35 #define FIFO_AF_LVL_MASK GENMASK(19, 16) 36 #define FIFO_AF_LVL 16 37 #define FIFO_AE_LVL_MASK GENMASK(15, 12) 38 #define FIFO_AE_LVL 12 39 #define I2C_DMA_EN BIT(11) 40 #define FULL_INTEN BIT(10) 41 #define EMPTY_INTEN BIT(9) 42 #define I2C_DVD_OPT BIT(8) 43 #define I2C_OUT_OPT BIT(7) 44 #define I2C_TRIM_OPT BIT(6) 45 #define I2C_HS_MODE BIT(4) 46 #define I2C_MODE BIT(3) 47 #define I2C_EN BIT(2) 48 #define I2C_INT_EN BIT(1) 49 #define I2C_START BIT(0) 50 51 /* I2C_STATUS */ 52 #define SDA_IN BIT(21) 53 #define SCL_IN BIT(20) 54 #define FIFO_FULL BIT(4) 55 #define FIFO_EMPTY BIT(3) 56 #define I2C_INT BIT(2) 57 #define I2C_RX_ACK BIT(1) 58 #define I2C_BUSY BIT(0) 59 60 /* ADDR_RST */ 61 #define I2C_RST BIT(0) 62 63 #define I2C_FIFO_DEEP 12 64 #define I2C_FIFO_FULL_THLD 15 65 #define I2C_FIFO_EMPTY_THLD 4 66 #define I2C_DATA_STEP 8 67 #define I2C_ADDR_DVD0_CALC(high, low) \ 68 ((((high) & GENMASK(15, 0)) << 16) | ((low) & GENMASK(15, 0))) 69 #define I2C_ADDR_DVD1_CALC(high, low) \ 70 (((high) & GENMASK(31, 16)) | (((low) & GENMASK(31, 16)) >> 16)) 71 72 /* timeout (ms) for pm runtime autosuspend */ 73 #define SPRD_I2C_PM_TIMEOUT 1000 74 75 /* SPRD i2c data structure */ 76 struct sprd_i2c { 77 struct i2c_adapter adap; 78 struct device *dev; 79 void __iomem *base; 80 struct i2c_msg *msg; 81 struct clk *clk; 82 u32 src_clk; 83 u32 bus_freq; 84 struct completion complete; 85 u8 *buf; 86 u32 count; 87 int irq; 88 int err; 89 bool is_suspended; 90 }; 91 92 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count) 93 { 94 writel(count, i2c_dev->base + I2C_COUNT); 95 } 96 97 static void sprd_i2c_send_stop(struct sprd_i2c *i2c_dev, int stop) 98 { 99 u32 tmp = readl(i2c_dev->base + I2C_CTL); 100 101 if (stop) 102 writel(tmp & ~STP_EN, i2c_dev->base + I2C_CTL); 103 else 104 writel(tmp | STP_EN, i2c_dev->base + I2C_CTL); 105 } 106 107 static void sprd_i2c_clear_start(struct sprd_i2c *i2c_dev) 108 { 109 u32 tmp = readl(i2c_dev->base + I2C_CTL); 110 111 writel(tmp & ~I2C_START, i2c_dev->base + I2C_CTL); 112 } 113 114 static void sprd_i2c_clear_ack(struct sprd_i2c *i2c_dev) 115 { 116 u32 tmp = readl(i2c_dev->base + I2C_STATUS); 117 118 writel(tmp & ~I2C_RX_ACK, i2c_dev->base + I2C_STATUS); 119 } 120 121 static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev) 122 { 123 u32 tmp = readl(i2c_dev->base + I2C_STATUS); 124 125 writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS); 126 } 127 128 static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev) 129 { 130 writel(I2C_RST, i2c_dev->base + ADDR_RST); 131 } 132 133 static void sprd_i2c_set_devaddr(struct sprd_i2c *i2c_dev, struct i2c_msg *m) 134 { 135 writel(m->addr << 1, i2c_dev->base + I2C_ADDR_CFG); 136 } 137 138 static void sprd_i2c_write_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) 139 { 140 u32 i; 141 142 for (i = 0; i < len; i++) 143 writeb(buf[i], i2c_dev->base + I2C_TX); 144 } 145 146 static void sprd_i2c_read_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) 147 { 148 u32 i; 149 150 for (i = 0; i < len; i++) 151 buf[i] = readb(i2c_dev->base + I2C_RX); 152 } 153 154 static void sprd_i2c_set_full_thld(struct sprd_i2c *i2c_dev, u32 full_thld) 155 { 156 u32 tmp = readl(i2c_dev->base + I2C_CTL); 157 158 tmp &= ~FIFO_AF_LVL_MASK; 159 tmp |= full_thld << FIFO_AF_LVL; 160 writel(tmp, i2c_dev->base + I2C_CTL); 161 }; 162 163 static void sprd_i2c_set_empty_thld(struct sprd_i2c *i2c_dev, u32 empty_thld) 164 { 165 u32 tmp = readl(i2c_dev->base + I2C_CTL); 166 167 tmp &= ~FIFO_AE_LVL_MASK; 168 tmp |= empty_thld << FIFO_AE_LVL; 169 writel(tmp, i2c_dev->base + I2C_CTL); 170 }; 171 172 static void sprd_i2c_set_fifo_full_int(struct sprd_i2c *i2c_dev, int enable) 173 { 174 u32 tmp = readl(i2c_dev->base + I2C_CTL); 175 176 if (enable) 177 tmp |= FULL_INTEN; 178 else 179 tmp &= ~FULL_INTEN; 180 181 writel(tmp, i2c_dev->base + I2C_CTL); 182 }; 183 184 static void sprd_i2c_set_fifo_empty_int(struct sprd_i2c *i2c_dev, int enable) 185 { 186 u32 tmp = readl(i2c_dev->base + I2C_CTL); 187 188 if (enable) 189 tmp |= EMPTY_INTEN; 190 else 191 tmp &= ~EMPTY_INTEN; 192 193 writel(tmp, i2c_dev->base + I2C_CTL); 194 }; 195 196 static void sprd_i2c_opt_start(struct sprd_i2c *i2c_dev) 197 { 198 u32 tmp = readl(i2c_dev->base + I2C_CTL); 199 200 writel(tmp | I2C_START, i2c_dev->base + I2C_CTL); 201 } 202 203 static void sprd_i2c_opt_mode(struct sprd_i2c *i2c_dev, int rw) 204 { 205 u32 cmd = readl(i2c_dev->base + I2C_CTL) & ~I2C_MODE; 206 207 writel(cmd | rw << 3, i2c_dev->base + I2C_CTL); 208 } 209 210 static void sprd_i2c_data_transfer(struct sprd_i2c *i2c_dev) 211 { 212 u32 i2c_count = i2c_dev->count; 213 u32 need_tran = i2c_count <= I2C_FIFO_DEEP ? i2c_count : I2C_FIFO_DEEP; 214 struct i2c_msg *msg = i2c_dev->msg; 215 216 if (msg->flags & I2C_M_RD) { 217 sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, I2C_FIFO_FULL_THLD); 218 i2c_dev->count -= I2C_FIFO_FULL_THLD; 219 i2c_dev->buf += I2C_FIFO_FULL_THLD; 220 221 /* 222 * If the read data count is larger than rx fifo full threshold, 223 * we should enable the rx fifo full interrupt to read data 224 * again. 225 */ 226 if (i2c_dev->count >= I2C_FIFO_FULL_THLD) 227 sprd_i2c_set_fifo_full_int(i2c_dev, 1); 228 } else { 229 sprd_i2c_write_bytes(i2c_dev, i2c_dev->buf, need_tran); 230 i2c_dev->buf += need_tran; 231 i2c_dev->count -= need_tran; 232 233 /* 234 * If the write data count is arger than tx fifo depth which 235 * means we can not write all data in one time, then we should 236 * enable the tx fifo empty interrupt to write again. 237 */ 238 if (i2c_count > I2C_FIFO_DEEP) 239 sprd_i2c_set_fifo_empty_int(i2c_dev, 1); 240 } 241 } 242 243 static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap, 244 struct i2c_msg *msg, bool is_last_msg) 245 { 246 struct sprd_i2c *i2c_dev = i2c_adap->algo_data; 247 248 i2c_dev->msg = msg; 249 i2c_dev->buf = msg->buf; 250 i2c_dev->count = msg->len; 251 252 reinit_completion(&i2c_dev->complete); 253 sprd_i2c_reset_fifo(i2c_dev); 254 sprd_i2c_set_devaddr(i2c_dev, msg); 255 sprd_i2c_set_count(i2c_dev, msg->len); 256 257 if (msg->flags & I2C_M_RD) { 258 sprd_i2c_opt_mode(i2c_dev, 1); 259 sprd_i2c_send_stop(i2c_dev, 1); 260 } else { 261 sprd_i2c_opt_mode(i2c_dev, 0); 262 sprd_i2c_send_stop(i2c_dev, !!is_last_msg); 263 } 264 265 /* 266 * We should enable rx fifo full interrupt to get data when receiving 267 * full data. 268 */ 269 if (msg->flags & I2C_M_RD) 270 sprd_i2c_set_fifo_full_int(i2c_dev, 1); 271 else 272 sprd_i2c_data_transfer(i2c_dev); 273 274 sprd_i2c_opt_start(i2c_dev); 275 276 wait_for_completion(&i2c_dev->complete); 277 278 return i2c_dev->err; 279 } 280 281 static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap, 282 struct i2c_msg *msgs, int num) 283 { 284 struct sprd_i2c *i2c_dev = i2c_adap->algo_data; 285 int im, ret; 286 287 if (i2c_dev->is_suspended) 288 return -EBUSY; 289 290 ret = pm_runtime_get_sync(i2c_dev->dev); 291 if (ret < 0) 292 return ret; 293 294 for (im = 0; im < num - 1; im++) { 295 ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0); 296 if (ret) 297 goto err_msg; 298 } 299 300 ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im++], 1); 301 302 err_msg: 303 pm_runtime_mark_last_busy(i2c_dev->dev); 304 pm_runtime_put_autosuspend(i2c_dev->dev); 305 306 return ret < 0 ? ret : im; 307 } 308 309 static u32 sprd_i2c_func(struct i2c_adapter *adap) 310 { 311 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 312 } 313 314 static const struct i2c_algorithm sprd_i2c_algo = { 315 .master_xfer = sprd_i2c_master_xfer, 316 .functionality = sprd_i2c_func, 317 }; 318 319 static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq) 320 { 321 u32 apb_clk = i2c_dev->src_clk; 322 /* 323 * From I2C databook, the prescale calculation formula: 324 * prescale = freq_i2c / (4 * freq_scl) - 1; 325 */ 326 u32 i2c_dvd = apb_clk / (4 * freq) - 1; 327 /* 328 * From I2C databook, the high period of SCL clock is recommended as 329 * 40% (2/5), and the low period of SCL clock is recommended as 60% 330 * (3/5), then the formula should be: 331 * high = (prescale * 2 * 2) / 5 332 * low = (prescale * 2 * 3) / 5 333 */ 334 u32 high = ((i2c_dvd << 1) * 2) / 5; 335 u32 low = ((i2c_dvd << 1) * 3) / 5; 336 u32 div0 = I2C_ADDR_DVD0_CALC(high, low); 337 u32 div1 = I2C_ADDR_DVD1_CALC(high, low); 338 339 writel(div0, i2c_dev->base + ADDR_DVD0); 340 writel(div1, i2c_dev->base + ADDR_DVD1); 341 342 /* Start hold timing = hold time(us) * source clock */ 343 if (freq == 400000) 344 writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); 345 else if (freq == 100000) 346 writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD); 347 } 348 349 static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) 350 { 351 u32 tmp = I2C_DVD_OPT; 352 353 writel(tmp, i2c_dev->base + I2C_CTL); 354 355 sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD); 356 sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD); 357 358 sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq); 359 sprd_i2c_reset_fifo(i2c_dev); 360 sprd_i2c_clear_irq(i2c_dev); 361 362 tmp = readl(i2c_dev->base + I2C_CTL); 363 writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); 364 } 365 366 static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id) 367 { 368 struct sprd_i2c *i2c_dev = dev_id; 369 struct i2c_msg *msg = i2c_dev->msg; 370 bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); 371 u32 i2c_tran; 372 373 if (msg->flags & I2C_M_RD) 374 i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; 375 else 376 i2c_tran = i2c_dev->count; 377 378 /* 379 * If we got one ACK from slave when writing data, and we did not 380 * finish this transmission (i2c_tran is not zero), then we should 381 * continue to write data. 382 * 383 * For reading data, ack is always true, if i2c_tran is not 0 which 384 * means we still need to contine to read data from slave. 385 */ 386 if (i2c_tran && ack) { 387 sprd_i2c_data_transfer(i2c_dev); 388 return IRQ_HANDLED; 389 } 390 391 i2c_dev->err = 0; 392 393 /* 394 * If we did not get one ACK from slave when writing data, we should 395 * return -EIO to notify users. 396 */ 397 if (!ack) 398 i2c_dev->err = -EIO; 399 else if (msg->flags & I2C_M_RD && i2c_dev->count) 400 sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, i2c_dev->count); 401 402 /* Transmission is done and clear ack and start operation */ 403 sprd_i2c_clear_ack(i2c_dev); 404 sprd_i2c_clear_start(i2c_dev); 405 complete(&i2c_dev->complete); 406 407 return IRQ_HANDLED; 408 } 409 410 static irqreturn_t sprd_i2c_isr(int irq, void *dev_id) 411 { 412 struct sprd_i2c *i2c_dev = dev_id; 413 struct i2c_msg *msg = i2c_dev->msg; 414 bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); 415 u32 i2c_tran; 416 417 if (msg->flags & I2C_M_RD) 418 i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; 419 else 420 i2c_tran = i2c_dev->count; 421 422 /* 423 * If we did not get one ACK from slave when writing data, then we 424 * should finish this transmission since we got some errors. 425 * 426 * When writing data, if i2c_tran == 0 which means we have writen 427 * done all data, then we can finish this transmission. 428 * 429 * When reading data, if conut < rx fifo full threshold, which 430 * means we can read all data in one time, then we can finish this 431 * transmission too. 432 */ 433 if (!i2c_tran || !ack) { 434 sprd_i2c_clear_start(i2c_dev); 435 sprd_i2c_clear_irq(i2c_dev); 436 } 437 438 sprd_i2c_set_fifo_empty_int(i2c_dev, 0); 439 sprd_i2c_set_fifo_full_int(i2c_dev, 0); 440 441 return IRQ_WAKE_THREAD; 442 } 443 444 static int sprd_i2c_clk_init(struct sprd_i2c *i2c_dev) 445 { 446 struct clk *clk_i2c, *clk_parent; 447 448 clk_i2c = devm_clk_get(i2c_dev->dev, "i2c"); 449 if (IS_ERR(clk_i2c)) { 450 dev_warn(i2c_dev->dev, "i2c%d can't get the i2c clock\n", 451 i2c_dev->adap.nr); 452 clk_i2c = NULL; 453 } 454 455 clk_parent = devm_clk_get(i2c_dev->dev, "source"); 456 if (IS_ERR(clk_parent)) { 457 dev_warn(i2c_dev->dev, "i2c%d can't get the source clock\n", 458 i2c_dev->adap.nr); 459 clk_parent = NULL; 460 } 461 462 if (clk_set_parent(clk_i2c, clk_parent)) 463 i2c_dev->src_clk = clk_get_rate(clk_i2c); 464 else 465 i2c_dev->src_clk = 26000000; 466 467 dev_dbg(i2c_dev->dev, "i2c%d set source clock is %d\n", 468 i2c_dev->adap.nr, i2c_dev->src_clk); 469 470 i2c_dev->clk = devm_clk_get(i2c_dev->dev, "enable"); 471 if (IS_ERR(i2c_dev->clk)) { 472 dev_warn(i2c_dev->dev, "i2c%d can't get the enable clock\n", 473 i2c_dev->adap.nr); 474 i2c_dev->clk = NULL; 475 } 476 477 return 0; 478 } 479 480 static int sprd_i2c_probe(struct platform_device *pdev) 481 { 482 struct device *dev = &pdev->dev; 483 struct sprd_i2c *i2c_dev; 484 struct resource *res; 485 u32 prop; 486 int ret; 487 488 pdev->id = of_alias_get_id(dev->of_node, "i2c"); 489 490 i2c_dev = devm_kzalloc(dev, sizeof(struct sprd_i2c), GFP_KERNEL); 491 if (!i2c_dev) 492 return -ENOMEM; 493 494 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 495 i2c_dev->base = devm_ioremap_resource(dev, res); 496 if (IS_ERR(i2c_dev->base)) 497 return PTR_ERR(i2c_dev->base); 498 499 i2c_dev->irq = platform_get_irq(pdev, 0); 500 if (i2c_dev->irq < 0) { 501 dev_err(&pdev->dev, "failed to get irq resource\n"); 502 return i2c_dev->irq; 503 } 504 505 i2c_set_adapdata(&i2c_dev->adap, i2c_dev); 506 init_completion(&i2c_dev->complete); 507 snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name), 508 "%s", "sprd-i2c"); 509 510 i2c_dev->bus_freq = 100000; 511 i2c_dev->adap.owner = THIS_MODULE; 512 i2c_dev->dev = dev; 513 i2c_dev->adap.retries = 3; 514 i2c_dev->adap.algo = &sprd_i2c_algo; 515 i2c_dev->adap.algo_data = i2c_dev; 516 i2c_dev->adap.dev.parent = dev; 517 i2c_dev->adap.nr = pdev->id; 518 i2c_dev->adap.dev.of_node = dev->of_node; 519 520 if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop)) 521 i2c_dev->bus_freq = prop; 522 523 /* We only support 100k and 400k now, otherwise will return error. */ 524 if (i2c_dev->bus_freq != 100000 && i2c_dev->bus_freq != 400000) 525 return -EINVAL; 526 527 sprd_i2c_clk_init(i2c_dev); 528 platform_set_drvdata(pdev, i2c_dev); 529 530 ret = clk_prepare_enable(i2c_dev->clk); 531 if (ret) 532 return ret; 533 534 sprd_i2c_enable(i2c_dev); 535 536 pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT); 537 pm_runtime_use_autosuspend(i2c_dev->dev); 538 pm_runtime_set_active(i2c_dev->dev); 539 pm_runtime_enable(i2c_dev->dev); 540 541 ret = pm_runtime_get_sync(i2c_dev->dev); 542 if (ret < 0) 543 goto err_rpm_put; 544 545 ret = devm_request_threaded_irq(dev, i2c_dev->irq, 546 sprd_i2c_isr, sprd_i2c_isr_thread, 547 IRQF_NO_SUSPEND | IRQF_ONESHOT, 548 pdev->name, i2c_dev); 549 if (ret) { 550 dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq); 551 goto err_rpm_put; 552 } 553 554 ret = i2c_add_numbered_adapter(&i2c_dev->adap); 555 if (ret) { 556 dev_err(&pdev->dev, "add adapter failed\n"); 557 goto err_rpm_put; 558 } 559 560 pm_runtime_mark_last_busy(i2c_dev->dev); 561 pm_runtime_put_autosuspend(i2c_dev->dev); 562 return 0; 563 564 err_rpm_put: 565 pm_runtime_put_noidle(i2c_dev->dev); 566 pm_runtime_disable(i2c_dev->dev); 567 clk_disable_unprepare(i2c_dev->clk); 568 return ret; 569 } 570 571 static int sprd_i2c_remove(struct platform_device *pdev) 572 { 573 struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev); 574 int ret; 575 576 ret = pm_runtime_get_sync(i2c_dev->dev); 577 if (ret < 0) 578 return ret; 579 580 i2c_del_adapter(&i2c_dev->adap); 581 clk_disable_unprepare(i2c_dev->clk); 582 583 pm_runtime_put_noidle(i2c_dev->dev); 584 pm_runtime_disable(i2c_dev->dev); 585 586 return 0; 587 } 588 589 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *pdev) 590 { 591 struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev); 592 593 i2c_lock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); 594 i2c_dev->is_suspended = true; 595 i2c_unlock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); 596 597 return pm_runtime_force_suspend(pdev); 598 } 599 600 static int __maybe_unused sprd_i2c_resume_noirq(struct device *pdev) 601 { 602 struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev); 603 604 i2c_lock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); 605 i2c_dev->is_suspended = false; 606 i2c_unlock_bus(&i2c_dev->adap, I2C_LOCK_ROOT_ADAPTER); 607 608 return pm_runtime_force_resume(pdev); 609 } 610 611 static int __maybe_unused sprd_i2c_runtime_suspend(struct device *pdev) 612 { 613 struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev); 614 615 clk_disable_unprepare(i2c_dev->clk); 616 617 return 0; 618 } 619 620 static int __maybe_unused sprd_i2c_runtime_resume(struct device *pdev) 621 { 622 struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev); 623 int ret; 624 625 ret = clk_prepare_enable(i2c_dev->clk); 626 if (ret) 627 return ret; 628 629 sprd_i2c_enable(i2c_dev); 630 631 return 0; 632 } 633 634 static const struct dev_pm_ops sprd_i2c_pm_ops = { 635 SET_RUNTIME_PM_OPS(sprd_i2c_runtime_suspend, 636 sprd_i2c_runtime_resume, NULL) 637 638 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sprd_i2c_suspend_noirq, 639 sprd_i2c_resume_noirq) 640 }; 641 642 static const struct of_device_id sprd_i2c_of_match[] = { 643 { .compatible = "sprd,sc9860-i2c", }, 644 {}, 645 }; 646 647 static struct platform_driver sprd_i2c_driver = { 648 .probe = sprd_i2c_probe, 649 .remove = sprd_i2c_remove, 650 .driver = { 651 .name = "sprd-i2c", 652 .of_match_table = sprd_i2c_of_match, 653 .pm = &sprd_i2c_pm_ops, 654 }, 655 }; 656 657 static int sprd_i2c_init(void) 658 { 659 return platform_driver_register(&sprd_i2c_driver); 660 } 661 arch_initcall_sync(sprd_i2c_init); 662