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/module.h> 16 #include <linux/of.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 /* timeout (ms) for transfer message */ 75 #define I2C_XFER_TIMEOUT 1000 76 77 /* SPRD i2c data structure */ 78 struct sprd_i2c { 79 struct i2c_adapter adap; 80 struct device *dev; 81 void __iomem *base; 82 struct i2c_msg *msg; 83 struct clk *clk; 84 u32 src_clk; 85 u32 bus_freq; 86 struct completion complete; 87 u8 *buf; 88 u32 count; 89 int irq; 90 int err; 91 }; 92 93 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count) 94 { 95 writel(count, i2c_dev->base + I2C_COUNT); 96 } 97 98 static void sprd_i2c_send_stop(struct sprd_i2c *i2c_dev, int stop) 99 { 100 u32 tmp = readl(i2c_dev->base + I2C_CTL); 101 102 if (stop) 103 writel(tmp & ~STP_EN, i2c_dev->base + I2C_CTL); 104 else 105 writel(tmp | STP_EN, i2c_dev->base + I2C_CTL); 106 } 107 108 static void sprd_i2c_clear_start(struct sprd_i2c *i2c_dev) 109 { 110 u32 tmp = readl(i2c_dev->base + I2C_CTL); 111 112 writel(tmp & ~I2C_START, i2c_dev->base + I2C_CTL); 113 } 114 115 static void sprd_i2c_clear_ack(struct sprd_i2c *i2c_dev) 116 { 117 u32 tmp = readl(i2c_dev->base + I2C_STATUS); 118 119 writel(tmp & ~I2C_RX_ACK, i2c_dev->base + I2C_STATUS); 120 } 121 122 static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev) 123 { 124 u32 tmp = readl(i2c_dev->base + I2C_STATUS); 125 126 writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS); 127 } 128 129 static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev) 130 { 131 writel(I2C_RST, i2c_dev->base + ADDR_RST); 132 } 133 134 static void sprd_i2c_set_devaddr(struct sprd_i2c *i2c_dev, struct i2c_msg *m) 135 { 136 writel(m->addr << 1, i2c_dev->base + I2C_ADDR_CFG); 137 } 138 139 static void sprd_i2c_write_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) 140 { 141 u32 i; 142 143 for (i = 0; i < len; i++) 144 writeb(buf[i], i2c_dev->base + I2C_TX); 145 } 146 147 static void sprd_i2c_read_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len) 148 { 149 u32 i; 150 151 for (i = 0; i < len; i++) 152 buf[i] = readb(i2c_dev->base + I2C_RX); 153 } 154 155 static void sprd_i2c_set_full_thld(struct sprd_i2c *i2c_dev, u32 full_thld) 156 { 157 u32 tmp = readl(i2c_dev->base + I2C_CTL); 158 159 tmp &= ~FIFO_AF_LVL_MASK; 160 tmp |= full_thld << FIFO_AF_LVL; 161 writel(tmp, i2c_dev->base + I2C_CTL); 162 }; 163 164 static void sprd_i2c_set_empty_thld(struct sprd_i2c *i2c_dev, u32 empty_thld) 165 { 166 u32 tmp = readl(i2c_dev->base + I2C_CTL); 167 168 tmp &= ~FIFO_AE_LVL_MASK; 169 tmp |= empty_thld << FIFO_AE_LVL; 170 writel(tmp, i2c_dev->base + I2C_CTL); 171 }; 172 173 static void sprd_i2c_set_fifo_full_int(struct sprd_i2c *i2c_dev, int enable) 174 { 175 u32 tmp = readl(i2c_dev->base + I2C_CTL); 176 177 if (enable) 178 tmp |= FULL_INTEN; 179 else 180 tmp &= ~FULL_INTEN; 181 182 writel(tmp, i2c_dev->base + I2C_CTL); 183 }; 184 185 static void sprd_i2c_set_fifo_empty_int(struct sprd_i2c *i2c_dev, int enable) 186 { 187 u32 tmp = readl(i2c_dev->base + I2C_CTL); 188 189 if (enable) 190 tmp |= EMPTY_INTEN; 191 else 192 tmp &= ~EMPTY_INTEN; 193 194 writel(tmp, i2c_dev->base + I2C_CTL); 195 }; 196 197 static void sprd_i2c_opt_start(struct sprd_i2c *i2c_dev) 198 { 199 u32 tmp = readl(i2c_dev->base + I2C_CTL); 200 201 writel(tmp | I2C_START, i2c_dev->base + I2C_CTL); 202 } 203 204 static void sprd_i2c_opt_mode(struct sprd_i2c *i2c_dev, int rw) 205 { 206 u32 cmd = readl(i2c_dev->base + I2C_CTL) & ~I2C_MODE; 207 208 writel(cmd | rw << 3, i2c_dev->base + I2C_CTL); 209 } 210 211 static void sprd_i2c_data_transfer(struct sprd_i2c *i2c_dev) 212 { 213 u32 i2c_count = i2c_dev->count; 214 u32 need_tran = i2c_count <= I2C_FIFO_DEEP ? i2c_count : I2C_FIFO_DEEP; 215 struct i2c_msg *msg = i2c_dev->msg; 216 217 if (msg->flags & I2C_M_RD) { 218 sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, I2C_FIFO_FULL_THLD); 219 i2c_dev->count -= I2C_FIFO_FULL_THLD; 220 i2c_dev->buf += I2C_FIFO_FULL_THLD; 221 222 /* 223 * If the read data count is larger than rx fifo full threshold, 224 * we should enable the rx fifo full interrupt to read data 225 * again. 226 */ 227 if (i2c_dev->count >= I2C_FIFO_FULL_THLD) 228 sprd_i2c_set_fifo_full_int(i2c_dev, 1); 229 } else { 230 sprd_i2c_write_bytes(i2c_dev, i2c_dev->buf, need_tran); 231 i2c_dev->buf += need_tran; 232 i2c_dev->count -= need_tran; 233 234 /* 235 * If the write data count is arger than tx fifo depth which 236 * means we can not write all data in one time, then we should 237 * enable the tx fifo empty interrupt to write again. 238 */ 239 if (i2c_count > I2C_FIFO_DEEP) 240 sprd_i2c_set_fifo_empty_int(i2c_dev, 1); 241 } 242 } 243 244 static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap, 245 struct i2c_msg *msg, bool is_last_msg) 246 { 247 struct sprd_i2c *i2c_dev = i2c_adap->algo_data; 248 unsigned long time_left; 249 250 i2c_dev->msg = msg; 251 i2c_dev->buf = msg->buf; 252 i2c_dev->count = msg->len; 253 254 reinit_completion(&i2c_dev->complete); 255 sprd_i2c_reset_fifo(i2c_dev); 256 sprd_i2c_set_devaddr(i2c_dev, msg); 257 sprd_i2c_set_count(i2c_dev, msg->len); 258 259 if (msg->flags & I2C_M_RD) { 260 sprd_i2c_opt_mode(i2c_dev, 1); 261 sprd_i2c_send_stop(i2c_dev, 1); 262 } else { 263 sprd_i2c_opt_mode(i2c_dev, 0); 264 sprd_i2c_send_stop(i2c_dev, !!is_last_msg); 265 } 266 267 /* 268 * We should enable rx fifo full interrupt to get data when receiving 269 * full data. 270 */ 271 if (msg->flags & I2C_M_RD) 272 sprd_i2c_set_fifo_full_int(i2c_dev, 1); 273 else 274 sprd_i2c_data_transfer(i2c_dev); 275 276 sprd_i2c_opt_start(i2c_dev); 277 278 time_left = wait_for_completion_timeout(&i2c_dev->complete, 279 msecs_to_jiffies(I2C_XFER_TIMEOUT)); 280 if (!time_left) 281 return -ETIMEDOUT; 282 283 return i2c_dev->err; 284 } 285 286 static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap, 287 struct i2c_msg *msgs, int num) 288 { 289 struct sprd_i2c *i2c_dev = i2c_adap->algo_data; 290 int im, ret; 291 292 ret = pm_runtime_resume_and_get(i2c_dev->dev); 293 if (ret < 0) 294 return ret; 295 296 for (im = 0; im < num - 1; im++) { 297 ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0); 298 if (ret) 299 goto err_msg; 300 } 301 302 ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im++], 1); 303 304 err_msg: 305 pm_runtime_mark_last_busy(i2c_dev->dev); 306 pm_runtime_put_autosuspend(i2c_dev->dev); 307 308 return ret < 0 ? ret : im; 309 } 310 311 static u32 sprd_i2c_func(struct i2c_adapter *adap) 312 { 313 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 314 } 315 316 static const struct i2c_algorithm sprd_i2c_algo = { 317 .master_xfer = sprd_i2c_master_xfer, 318 .functionality = sprd_i2c_func, 319 }; 320 321 static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq) 322 { 323 u32 apb_clk = i2c_dev->src_clk; 324 /* 325 * From I2C databook, the prescale calculation formula: 326 * prescale = freq_i2c / (4 * freq_scl) - 1; 327 */ 328 u32 i2c_dvd = apb_clk / (4 * freq) - 1; 329 /* 330 * From I2C databook, the high period of SCL clock is recommended as 331 * 40% (2/5), and the low period of SCL clock is recommended as 60% 332 * (3/5), then the formula should be: 333 * high = (prescale * 2 * 2) / 5 334 * low = (prescale * 2 * 3) / 5 335 */ 336 u32 high = ((i2c_dvd << 1) * 2) / 5; 337 u32 low = ((i2c_dvd << 1) * 3) / 5; 338 u32 div0 = I2C_ADDR_DVD0_CALC(high, low); 339 u32 div1 = I2C_ADDR_DVD1_CALC(high, low); 340 341 writel(div0, i2c_dev->base + ADDR_DVD0); 342 writel(div1, i2c_dev->base + ADDR_DVD1); 343 344 /* Start hold timing = hold time(us) * source clock */ 345 if (freq == I2C_MAX_FAST_MODE_FREQ) 346 writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD); 347 else if (freq == I2C_MAX_STANDARD_MODE_FREQ) 348 writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD); 349 } 350 351 static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) 352 { 353 u32 tmp = I2C_DVD_OPT; 354 355 writel(tmp, i2c_dev->base + I2C_CTL); 356 357 sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD); 358 sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD); 359 360 sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq); 361 sprd_i2c_reset_fifo(i2c_dev); 362 sprd_i2c_clear_irq(i2c_dev); 363 364 tmp = readl(i2c_dev->base + I2C_CTL); 365 writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); 366 } 367 368 static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id) 369 { 370 struct sprd_i2c *i2c_dev = dev_id; 371 struct i2c_msg *msg = i2c_dev->msg; 372 bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); 373 u32 i2c_tran; 374 375 if (msg->flags & I2C_M_RD) 376 i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; 377 else 378 i2c_tran = i2c_dev->count; 379 380 /* 381 * If we got one ACK from slave when writing data, and we did not 382 * finish this transmission (i2c_tran is not zero), then we should 383 * continue to write data. 384 * 385 * For reading data, ack is always true, if i2c_tran is not 0 which 386 * means we still need to contine to read data from slave. 387 */ 388 if (i2c_tran && ack) { 389 sprd_i2c_data_transfer(i2c_dev); 390 return IRQ_HANDLED; 391 } 392 393 i2c_dev->err = 0; 394 395 /* 396 * If we did not get one ACK from slave when writing data, we should 397 * return -EIO to notify users. 398 */ 399 if (!ack) 400 i2c_dev->err = -EIO; 401 else if (msg->flags & I2C_M_RD && i2c_dev->count) 402 sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, i2c_dev->count); 403 404 /* Transmission is done and clear ack and start operation */ 405 sprd_i2c_clear_ack(i2c_dev); 406 sprd_i2c_clear_start(i2c_dev); 407 complete(&i2c_dev->complete); 408 409 return IRQ_HANDLED; 410 } 411 412 static irqreturn_t sprd_i2c_isr(int irq, void *dev_id) 413 { 414 struct sprd_i2c *i2c_dev = dev_id; 415 struct i2c_msg *msg = i2c_dev->msg; 416 bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); 417 u32 i2c_tran; 418 419 if (msg->flags & I2C_M_RD) 420 i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; 421 else 422 i2c_tran = i2c_dev->count; 423 424 /* 425 * If we did not get one ACK from slave when writing data, then we 426 * should finish this transmission since we got some errors. 427 * 428 * When writing data, if i2c_tran == 0 which means we have writen 429 * done all data, then we can finish this transmission. 430 * 431 * When reading data, if conut < rx fifo full threshold, which 432 * means we can read all data in one time, then we can finish this 433 * transmission too. 434 */ 435 if (!i2c_tran || !ack) { 436 sprd_i2c_clear_start(i2c_dev); 437 sprd_i2c_clear_irq(i2c_dev); 438 } 439 440 sprd_i2c_set_fifo_empty_int(i2c_dev, 0); 441 sprd_i2c_set_fifo_full_int(i2c_dev, 0); 442 443 return IRQ_WAKE_THREAD; 444 } 445 446 static int sprd_i2c_clk_init(struct sprd_i2c *i2c_dev) 447 { 448 struct clk *clk_i2c, *clk_parent; 449 450 clk_i2c = devm_clk_get(i2c_dev->dev, "i2c"); 451 if (IS_ERR(clk_i2c)) { 452 dev_warn(i2c_dev->dev, "i2c%d can't get the i2c clock\n", 453 i2c_dev->adap.nr); 454 clk_i2c = NULL; 455 } 456 457 clk_parent = devm_clk_get(i2c_dev->dev, "source"); 458 if (IS_ERR(clk_parent)) { 459 dev_warn(i2c_dev->dev, "i2c%d can't get the source clock\n", 460 i2c_dev->adap.nr); 461 clk_parent = NULL; 462 } 463 464 if (clk_set_parent(clk_i2c, clk_parent)) 465 i2c_dev->src_clk = clk_get_rate(clk_i2c); 466 else 467 i2c_dev->src_clk = 26000000; 468 469 dev_dbg(i2c_dev->dev, "i2c%d set source clock is %d\n", 470 i2c_dev->adap.nr, i2c_dev->src_clk); 471 472 i2c_dev->clk = devm_clk_get(i2c_dev->dev, "enable"); 473 if (IS_ERR(i2c_dev->clk)) { 474 dev_err(i2c_dev->dev, "i2c%d can't get the enable clock\n", 475 i2c_dev->adap.nr); 476 return PTR_ERR(i2c_dev->clk); 477 } 478 479 return 0; 480 } 481 482 static int sprd_i2c_probe(struct platform_device *pdev) 483 { 484 struct device *dev = &pdev->dev; 485 struct sprd_i2c *i2c_dev; 486 u32 prop; 487 int ret; 488 489 pdev->id = of_alias_get_id(dev->of_node, "i2c"); 490 491 i2c_dev = devm_kzalloc(dev, sizeof(struct sprd_i2c), GFP_KERNEL); 492 if (!i2c_dev) 493 return -ENOMEM; 494 495 i2c_dev->base = devm_platform_ioremap_resource(pdev, 0); 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 return i2c_dev->irq; 502 503 i2c_set_adapdata(&i2c_dev->adap, i2c_dev); 504 init_completion(&i2c_dev->complete); 505 snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name), 506 "%s", "sprd-i2c"); 507 508 i2c_dev->bus_freq = I2C_MAX_STANDARD_MODE_FREQ; 509 i2c_dev->adap.owner = THIS_MODULE; 510 i2c_dev->dev = dev; 511 i2c_dev->adap.retries = 3; 512 i2c_dev->adap.algo = &sprd_i2c_algo; 513 i2c_dev->adap.algo_data = i2c_dev; 514 i2c_dev->adap.dev.parent = dev; 515 i2c_dev->adap.nr = pdev->id; 516 i2c_dev->adap.dev.of_node = dev->of_node; 517 518 if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop)) 519 i2c_dev->bus_freq = prop; 520 521 /* We only support 100k and 400k now, otherwise will return error. */ 522 if (i2c_dev->bus_freq != I2C_MAX_STANDARD_MODE_FREQ && 523 i2c_dev->bus_freq != I2C_MAX_FAST_MODE_FREQ) 524 return -EINVAL; 525 526 ret = sprd_i2c_clk_init(i2c_dev); 527 if (ret) 528 return ret; 529 530 platform_set_drvdata(pdev, i2c_dev); 531 532 ret = clk_prepare_enable(i2c_dev->clk); 533 if (ret) 534 return ret; 535 536 sprd_i2c_enable(i2c_dev); 537 538 pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT); 539 pm_runtime_use_autosuspend(i2c_dev->dev); 540 pm_runtime_set_active(i2c_dev->dev); 541 pm_runtime_enable(i2c_dev->dev); 542 543 ret = pm_runtime_get_sync(i2c_dev->dev); 544 if (ret < 0) 545 goto err_rpm_put; 546 547 ret = devm_request_threaded_irq(dev, i2c_dev->irq, 548 sprd_i2c_isr, sprd_i2c_isr_thread, 549 IRQF_NO_SUSPEND | IRQF_ONESHOT, 550 pdev->name, i2c_dev); 551 if (ret) { 552 dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq); 553 goto err_rpm_put; 554 } 555 556 ret = i2c_add_numbered_adapter(&i2c_dev->adap); 557 if (ret) { 558 dev_err(&pdev->dev, "add adapter failed\n"); 559 goto err_rpm_put; 560 } 561 562 pm_runtime_mark_last_busy(i2c_dev->dev); 563 pm_runtime_put_autosuspend(i2c_dev->dev); 564 return 0; 565 566 err_rpm_put: 567 pm_runtime_put_noidle(i2c_dev->dev); 568 pm_runtime_disable(i2c_dev->dev); 569 clk_disable_unprepare(i2c_dev->clk); 570 return ret; 571 } 572 573 static int sprd_i2c_remove(struct platform_device *pdev) 574 { 575 struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev); 576 int ret; 577 578 ret = pm_runtime_get_sync(i2c_dev->dev); 579 if (ret < 0) 580 dev_err(&pdev->dev, "Failed to resume device (%pe)\n", ERR_PTR(ret)); 581 582 i2c_del_adapter(&i2c_dev->adap); 583 584 if (ret >= 0) 585 clk_disable_unprepare(i2c_dev->clk); 586 587 pm_runtime_put_noidle(i2c_dev->dev); 588 pm_runtime_disable(i2c_dev->dev); 589 590 return 0; 591 } 592 593 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *dev) 594 { 595 struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); 596 597 i2c_mark_adapter_suspended(&i2c_dev->adap); 598 return pm_runtime_force_suspend(dev); 599 } 600 601 static int __maybe_unused sprd_i2c_resume_noirq(struct device *dev) 602 { 603 struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); 604 605 i2c_mark_adapter_resumed(&i2c_dev->adap); 606 return pm_runtime_force_resume(dev); 607 } 608 609 static int __maybe_unused sprd_i2c_runtime_suspend(struct device *dev) 610 { 611 struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); 612 613 clk_disable_unprepare(i2c_dev->clk); 614 615 return 0; 616 } 617 618 static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev) 619 { 620 struct sprd_i2c *i2c_dev = dev_get_drvdata(dev); 621 int ret; 622 623 ret = clk_prepare_enable(i2c_dev->clk); 624 if (ret) 625 return ret; 626 627 sprd_i2c_enable(i2c_dev); 628 629 return 0; 630 } 631 632 static const struct dev_pm_ops sprd_i2c_pm_ops = { 633 SET_RUNTIME_PM_OPS(sprd_i2c_runtime_suspend, 634 sprd_i2c_runtime_resume, NULL) 635 636 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sprd_i2c_suspend_noirq, 637 sprd_i2c_resume_noirq) 638 }; 639 640 static const struct of_device_id sprd_i2c_of_match[] = { 641 { .compatible = "sprd,sc9860-i2c", }, 642 {}, 643 }; 644 MODULE_DEVICE_TABLE(of, sprd_i2c_of_match); 645 646 static struct platform_driver sprd_i2c_driver = { 647 .probe = sprd_i2c_probe, 648 .remove = sprd_i2c_remove, 649 .driver = { 650 .name = "sprd-i2c", 651 .of_match_table = sprd_i2c_of_match, 652 .pm = &sprd_i2c_pm_ops, 653 }, 654 }; 655 656 module_platform_driver(sprd_i2c_driver); 657 658 MODULE_DESCRIPTION("Spreadtrum I2C master controller driver"); 659 MODULE_LICENSE("GPL v2"); 660