1 // SPDX-License-Identifier: GPL-2.0+ 2 // Copyright (c) 2018 MediaTek Inc. 3 4 #include <linux/clk.h> 5 #include <linux/device.h> 6 #include <linux/dma-mapping.h> 7 #include <linux/err.h> 8 #include <linux/interrupt.h> 9 #include <linux/module.h> 10 #include <linux/platform_device.h> 11 #include <linux/pm_runtime.h> 12 #include <linux/spi/spi.h> 13 #include <linux/of.h> 14 15 16 #define SPIS_IRQ_EN_REG 0x0 17 #define SPIS_IRQ_CLR_REG 0x4 18 #define SPIS_IRQ_ST_REG 0x8 19 #define SPIS_IRQ_MASK_REG 0xc 20 #define SPIS_CFG_REG 0x10 21 #define SPIS_RX_DATA_REG 0x14 22 #define SPIS_TX_DATA_REG 0x18 23 #define SPIS_RX_DST_REG 0x1c 24 #define SPIS_TX_SRC_REG 0x20 25 #define SPIS_DMA_CFG_REG 0x30 26 #define SPIS_SOFT_RST_REG 0x40 27 28 /* SPIS_IRQ_EN_REG */ 29 #define DMA_DONE_EN BIT(7) 30 #define DATA_DONE_EN BIT(2) 31 #define RSTA_DONE_EN BIT(1) 32 #define CMD_INVALID_EN BIT(0) 33 34 /* SPIS_IRQ_ST_REG */ 35 #define DMA_DONE_ST BIT(7) 36 #define DATA_DONE_ST BIT(2) 37 #define RSTA_DONE_ST BIT(1) 38 #define CMD_INVALID_ST BIT(0) 39 40 /* SPIS_IRQ_MASK_REG */ 41 #define DMA_DONE_MASK BIT(7) 42 #define DATA_DONE_MASK BIT(2) 43 #define RSTA_DONE_MASK BIT(1) 44 #define CMD_INVALID_MASK BIT(0) 45 46 /* SPIS_CFG_REG */ 47 #define SPIS_TX_ENDIAN BIT(7) 48 #define SPIS_RX_ENDIAN BIT(6) 49 #define SPIS_TXMSBF BIT(5) 50 #define SPIS_RXMSBF BIT(4) 51 #define SPIS_CPHA BIT(3) 52 #define SPIS_CPOL BIT(2) 53 #define SPIS_TX_EN BIT(1) 54 #define SPIS_RX_EN BIT(0) 55 56 /* SPIS_DMA_CFG_REG */ 57 #define TX_DMA_TRIG_EN BIT(31) 58 #define TX_DMA_EN BIT(30) 59 #define RX_DMA_EN BIT(29) 60 #define TX_DMA_LEN 0xfffff 61 62 /* SPIS_SOFT_RST_REG */ 63 #define SPIS_DMA_ADDR_EN BIT(1) 64 #define SPIS_SOFT_RST BIT(0) 65 66 struct mtk_spi_slave { 67 struct device *dev; 68 void __iomem *base; 69 struct clk *spi_clk; 70 struct completion xfer_done; 71 struct spi_transfer *cur_transfer; 72 bool target_aborted; 73 const struct mtk_spi_compatible *dev_comp; 74 }; 75 76 struct mtk_spi_compatible { 77 const u32 max_fifo_size; 78 bool must_rx; 79 }; 80 81 static const struct mtk_spi_compatible mt2712_compat = { 82 .max_fifo_size = 512, 83 }; 84 static const struct mtk_spi_compatible mt8195_compat = { 85 .max_fifo_size = 128, 86 .must_rx = true, 87 }; 88 89 static const struct of_device_id mtk_spi_slave_of_match[] = { 90 { .compatible = "mediatek,mt2712-spi-slave", 91 .data = (void *)&mt2712_compat,}, 92 { .compatible = "mediatek,mt8195-spi-slave", 93 .data = (void *)&mt8195_compat,}, 94 {} 95 }; 96 MODULE_DEVICE_TABLE(of, mtk_spi_slave_of_match); 97 98 static void mtk_spi_slave_disable_dma(struct mtk_spi_slave *mdata) 99 { 100 u32 reg_val; 101 102 reg_val = readl(mdata->base + SPIS_DMA_CFG_REG); 103 reg_val &= ~RX_DMA_EN; 104 reg_val &= ~TX_DMA_EN; 105 writel(reg_val, mdata->base + SPIS_DMA_CFG_REG); 106 } 107 108 static void mtk_spi_slave_disable_xfer(struct mtk_spi_slave *mdata) 109 { 110 u32 reg_val; 111 112 reg_val = readl(mdata->base + SPIS_CFG_REG); 113 reg_val &= ~SPIS_TX_EN; 114 reg_val &= ~SPIS_RX_EN; 115 writel(reg_val, mdata->base + SPIS_CFG_REG); 116 } 117 118 static int mtk_spi_slave_wait_for_completion(struct mtk_spi_slave *mdata) 119 { 120 if (wait_for_completion_interruptible(&mdata->xfer_done) || 121 mdata->target_aborted) { 122 dev_err(mdata->dev, "interrupted\n"); 123 return -EINTR; 124 } 125 126 return 0; 127 } 128 129 static int mtk_spi_slave_prepare_message(struct spi_controller *ctlr, 130 struct spi_message *msg) 131 { 132 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 133 struct spi_device *spi = msg->spi; 134 bool cpha, cpol; 135 u32 reg_val; 136 137 cpha = spi->mode & SPI_CPHA ? 1 : 0; 138 cpol = spi->mode & SPI_CPOL ? 1 : 0; 139 140 reg_val = readl(mdata->base + SPIS_CFG_REG); 141 if (cpha) 142 reg_val |= SPIS_CPHA; 143 else 144 reg_val &= ~SPIS_CPHA; 145 if (cpol) 146 reg_val |= SPIS_CPOL; 147 else 148 reg_val &= ~SPIS_CPOL; 149 150 if (spi->mode & SPI_LSB_FIRST) 151 reg_val &= ~(SPIS_TXMSBF | SPIS_RXMSBF); 152 else 153 reg_val |= SPIS_TXMSBF | SPIS_RXMSBF; 154 155 reg_val &= ~SPIS_TX_ENDIAN; 156 reg_val &= ~SPIS_RX_ENDIAN; 157 writel(reg_val, mdata->base + SPIS_CFG_REG); 158 159 return 0; 160 } 161 162 static int mtk_spi_slave_fifo_transfer(struct spi_controller *ctlr, 163 struct spi_device *spi, 164 struct spi_transfer *xfer) 165 { 166 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 167 int reg_val, cnt, remainder, ret; 168 169 writel(SPIS_SOFT_RST, mdata->base + SPIS_SOFT_RST_REG); 170 171 reg_val = readl(mdata->base + SPIS_CFG_REG); 172 if (xfer->rx_buf) 173 reg_val |= SPIS_RX_EN; 174 if (xfer->tx_buf) 175 reg_val |= SPIS_TX_EN; 176 writel(reg_val, mdata->base + SPIS_CFG_REG); 177 178 cnt = xfer->len / 4; 179 if (xfer->tx_buf) 180 iowrite32_rep(mdata->base + SPIS_TX_DATA_REG, 181 xfer->tx_buf, cnt); 182 183 remainder = xfer->len % 4; 184 if (xfer->tx_buf && remainder > 0) { 185 reg_val = 0; 186 memcpy(®_val, xfer->tx_buf + cnt * 4, remainder); 187 writel(reg_val, mdata->base + SPIS_TX_DATA_REG); 188 } 189 190 ret = mtk_spi_slave_wait_for_completion(mdata); 191 if (ret) { 192 mtk_spi_slave_disable_xfer(mdata); 193 writel(SPIS_SOFT_RST, mdata->base + SPIS_SOFT_RST_REG); 194 } 195 196 return ret; 197 } 198 199 static int mtk_spi_slave_dma_transfer(struct spi_controller *ctlr, 200 struct spi_device *spi, 201 struct spi_transfer *xfer) 202 { 203 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 204 struct device *dev = mdata->dev; 205 int reg_val, ret; 206 207 writel(SPIS_SOFT_RST, mdata->base + SPIS_SOFT_RST_REG); 208 209 if (xfer->tx_buf) { 210 /* tx_buf is a const void* where we need a void * for 211 * the dma mapping 212 */ 213 void *nonconst_tx = (void *)xfer->tx_buf; 214 215 xfer->tx_dma = dma_map_single(dev, nonconst_tx, 216 xfer->len, DMA_TO_DEVICE); 217 if (dma_mapping_error(dev, xfer->tx_dma)) { 218 ret = -ENOMEM; 219 goto disable_transfer; 220 } 221 } 222 223 if (xfer->rx_buf) { 224 xfer->rx_dma = dma_map_single(dev, xfer->rx_buf, 225 xfer->len, DMA_FROM_DEVICE); 226 if (dma_mapping_error(dev, xfer->rx_dma)) { 227 ret = -ENOMEM; 228 goto unmap_txdma; 229 } 230 } 231 232 writel(xfer->tx_dma, mdata->base + SPIS_TX_SRC_REG); 233 writel(xfer->rx_dma, mdata->base + SPIS_RX_DST_REG); 234 235 writel(SPIS_DMA_ADDR_EN, mdata->base + SPIS_SOFT_RST_REG); 236 237 /* enable config reg tx rx_enable */ 238 reg_val = readl(mdata->base + SPIS_CFG_REG); 239 if (xfer->tx_buf) 240 reg_val |= SPIS_TX_EN; 241 if (xfer->rx_buf) 242 reg_val |= SPIS_RX_EN; 243 writel(reg_val, mdata->base + SPIS_CFG_REG); 244 245 /* config dma */ 246 reg_val = 0; 247 reg_val |= (xfer->len - 1) & TX_DMA_LEN; 248 writel(reg_val, mdata->base + SPIS_DMA_CFG_REG); 249 250 reg_val = readl(mdata->base + SPIS_DMA_CFG_REG); 251 if (xfer->tx_buf) 252 reg_val |= TX_DMA_EN; 253 if (xfer->rx_buf) 254 reg_val |= RX_DMA_EN; 255 reg_val |= TX_DMA_TRIG_EN; 256 writel(reg_val, mdata->base + SPIS_DMA_CFG_REG); 257 258 ret = mtk_spi_slave_wait_for_completion(mdata); 259 if (ret) 260 goto unmap_rxdma; 261 262 return 0; 263 264 unmap_rxdma: 265 if (xfer->rx_buf) 266 dma_unmap_single(dev, xfer->rx_dma, 267 xfer->len, DMA_FROM_DEVICE); 268 269 unmap_txdma: 270 if (xfer->tx_buf) 271 dma_unmap_single(dev, xfer->tx_dma, 272 xfer->len, DMA_TO_DEVICE); 273 274 disable_transfer: 275 mtk_spi_slave_disable_dma(mdata); 276 mtk_spi_slave_disable_xfer(mdata); 277 writel(SPIS_SOFT_RST, mdata->base + SPIS_SOFT_RST_REG); 278 279 return ret; 280 } 281 282 static int mtk_spi_slave_transfer_one(struct spi_controller *ctlr, 283 struct spi_device *spi, 284 struct spi_transfer *xfer) 285 { 286 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 287 288 reinit_completion(&mdata->xfer_done); 289 mdata->target_aborted = false; 290 mdata->cur_transfer = xfer; 291 292 if (xfer->len > mdata->dev_comp->max_fifo_size) 293 return mtk_spi_slave_dma_transfer(ctlr, spi, xfer); 294 else 295 return mtk_spi_slave_fifo_transfer(ctlr, spi, xfer); 296 } 297 298 static int mtk_spi_slave_setup(struct spi_device *spi) 299 { 300 struct mtk_spi_slave *mdata = spi_controller_get_devdata(spi->controller); 301 u32 reg_val; 302 303 reg_val = DMA_DONE_EN | DATA_DONE_EN | 304 RSTA_DONE_EN | CMD_INVALID_EN; 305 writel(reg_val, mdata->base + SPIS_IRQ_EN_REG); 306 307 reg_val = DMA_DONE_MASK | DATA_DONE_MASK | 308 RSTA_DONE_MASK | CMD_INVALID_MASK; 309 writel(reg_val, mdata->base + SPIS_IRQ_MASK_REG); 310 311 mtk_spi_slave_disable_dma(mdata); 312 mtk_spi_slave_disable_xfer(mdata); 313 314 return 0; 315 } 316 317 static int mtk_target_abort(struct spi_controller *ctlr) 318 { 319 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 320 321 mdata->target_aborted = true; 322 complete(&mdata->xfer_done); 323 324 return 0; 325 } 326 327 static irqreturn_t mtk_spi_slave_interrupt(int irq, void *dev_id) 328 { 329 struct spi_controller *ctlr = dev_id; 330 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 331 struct spi_transfer *trans = mdata->cur_transfer; 332 u32 int_status, reg_val, cnt, remainder; 333 334 int_status = readl(mdata->base + SPIS_IRQ_ST_REG); 335 writel(int_status, mdata->base + SPIS_IRQ_CLR_REG); 336 337 if (!trans) 338 return IRQ_NONE; 339 340 if ((int_status & DMA_DONE_ST) && 341 ((int_status & DATA_DONE_ST) || 342 (int_status & RSTA_DONE_ST))) { 343 writel(SPIS_SOFT_RST, mdata->base + SPIS_SOFT_RST_REG); 344 345 if (trans->tx_buf) 346 dma_unmap_single(mdata->dev, trans->tx_dma, 347 trans->len, DMA_TO_DEVICE); 348 if (trans->rx_buf) 349 dma_unmap_single(mdata->dev, trans->rx_dma, 350 trans->len, DMA_FROM_DEVICE); 351 352 mtk_spi_slave_disable_dma(mdata); 353 mtk_spi_slave_disable_xfer(mdata); 354 } 355 356 if ((!(int_status & DMA_DONE_ST)) && 357 ((int_status & DATA_DONE_ST) || 358 (int_status & RSTA_DONE_ST))) { 359 cnt = trans->len / 4; 360 if (trans->rx_buf) 361 ioread32_rep(mdata->base + SPIS_RX_DATA_REG, 362 trans->rx_buf, cnt); 363 remainder = trans->len % 4; 364 if (trans->rx_buf && remainder > 0) { 365 reg_val = readl(mdata->base + SPIS_RX_DATA_REG); 366 memcpy(trans->rx_buf + (cnt * 4), 367 ®_val, remainder); 368 } 369 370 mtk_spi_slave_disable_xfer(mdata); 371 } 372 373 if (int_status & CMD_INVALID_ST) { 374 dev_warn(&ctlr->dev, "cmd invalid\n"); 375 return IRQ_NONE; 376 } 377 378 mdata->cur_transfer = NULL; 379 complete(&mdata->xfer_done); 380 381 return IRQ_HANDLED; 382 } 383 384 static int mtk_spi_slave_probe(struct platform_device *pdev) 385 { 386 struct spi_controller *ctlr; 387 struct mtk_spi_slave *mdata; 388 int irq, ret; 389 const struct of_device_id *of_id; 390 391 ctlr = spi_alloc_target(&pdev->dev, sizeof(*mdata)); 392 if (!ctlr) { 393 dev_err(&pdev->dev, "failed to alloc spi target\n"); 394 return -ENOMEM; 395 } 396 397 ctlr->auto_runtime_pm = true; 398 ctlr->dev.of_node = pdev->dev.of_node; 399 ctlr->mode_bits = SPI_CPOL | SPI_CPHA; 400 ctlr->mode_bits |= SPI_LSB_FIRST; 401 402 ctlr->prepare_message = mtk_spi_slave_prepare_message; 403 ctlr->transfer_one = mtk_spi_slave_transfer_one; 404 ctlr->setup = mtk_spi_slave_setup; 405 ctlr->target_abort = mtk_target_abort; 406 407 of_id = of_match_node(mtk_spi_slave_of_match, pdev->dev.of_node); 408 if (!of_id) { 409 dev_err(&pdev->dev, "failed to probe of_node\n"); 410 ret = -EINVAL; 411 goto err_put_ctlr; 412 } 413 mdata = spi_controller_get_devdata(ctlr); 414 mdata->dev_comp = of_id->data; 415 416 if (mdata->dev_comp->must_rx) 417 ctlr->flags = SPI_CONTROLLER_MUST_RX; 418 419 platform_set_drvdata(pdev, ctlr); 420 421 init_completion(&mdata->xfer_done); 422 mdata->dev = &pdev->dev; 423 mdata->base = devm_platform_ioremap_resource(pdev, 0); 424 if (IS_ERR(mdata->base)) { 425 ret = PTR_ERR(mdata->base); 426 goto err_put_ctlr; 427 } 428 429 irq = platform_get_irq(pdev, 0); 430 if (irq < 0) { 431 ret = irq; 432 goto err_put_ctlr; 433 } 434 435 ret = devm_request_irq(&pdev->dev, irq, mtk_spi_slave_interrupt, 436 IRQF_TRIGGER_NONE, dev_name(&pdev->dev), ctlr); 437 if (ret) { 438 dev_err(&pdev->dev, "failed to register irq (%d)\n", ret); 439 goto err_put_ctlr; 440 } 441 442 mdata->spi_clk = devm_clk_get(&pdev->dev, "spi"); 443 if (IS_ERR(mdata->spi_clk)) { 444 ret = PTR_ERR(mdata->spi_clk); 445 dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret); 446 goto err_put_ctlr; 447 } 448 449 ret = clk_prepare_enable(mdata->spi_clk); 450 if (ret < 0) { 451 dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret); 452 goto err_put_ctlr; 453 } 454 455 pm_runtime_enable(&pdev->dev); 456 457 ret = devm_spi_register_controller(&pdev->dev, ctlr); 458 clk_disable_unprepare(mdata->spi_clk); 459 if (ret) { 460 dev_err(&pdev->dev, 461 "failed to register slave controller(%d)\n", ret); 462 goto err_disable_runtime_pm; 463 } 464 465 return 0; 466 467 err_disable_runtime_pm: 468 pm_runtime_disable(&pdev->dev); 469 err_put_ctlr: 470 spi_controller_put(ctlr); 471 472 return ret; 473 } 474 475 static void mtk_spi_slave_remove(struct platform_device *pdev) 476 { 477 pm_runtime_disable(&pdev->dev); 478 } 479 480 #ifdef CONFIG_PM_SLEEP 481 static int mtk_spi_slave_suspend(struct device *dev) 482 { 483 struct spi_controller *ctlr = dev_get_drvdata(dev); 484 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 485 int ret; 486 487 ret = spi_controller_suspend(ctlr); 488 if (ret) 489 return ret; 490 491 if (!pm_runtime_suspended(dev)) 492 clk_disable_unprepare(mdata->spi_clk); 493 494 return ret; 495 } 496 497 static int mtk_spi_slave_resume(struct device *dev) 498 { 499 struct spi_controller *ctlr = dev_get_drvdata(dev); 500 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 501 int ret; 502 503 if (!pm_runtime_suspended(dev)) { 504 ret = clk_prepare_enable(mdata->spi_clk); 505 if (ret < 0) { 506 dev_err(dev, "failed to enable spi_clk (%d)\n", ret); 507 return ret; 508 } 509 } 510 511 ret = spi_controller_resume(ctlr); 512 if (ret < 0) 513 clk_disable_unprepare(mdata->spi_clk); 514 515 return ret; 516 } 517 #endif /* CONFIG_PM_SLEEP */ 518 519 #ifdef CONFIG_PM 520 static int mtk_spi_slave_runtime_suspend(struct device *dev) 521 { 522 struct spi_controller *ctlr = dev_get_drvdata(dev); 523 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 524 525 clk_disable_unprepare(mdata->spi_clk); 526 527 return 0; 528 } 529 530 static int mtk_spi_slave_runtime_resume(struct device *dev) 531 { 532 struct spi_controller *ctlr = dev_get_drvdata(dev); 533 struct mtk_spi_slave *mdata = spi_controller_get_devdata(ctlr); 534 int ret; 535 536 ret = clk_prepare_enable(mdata->spi_clk); 537 if (ret < 0) { 538 dev_err(dev, "failed to enable spi_clk (%d)\n", ret); 539 return ret; 540 } 541 542 return 0; 543 } 544 #endif /* CONFIG_PM */ 545 546 static const struct dev_pm_ops mtk_spi_slave_pm = { 547 SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_slave_suspend, mtk_spi_slave_resume) 548 SET_RUNTIME_PM_OPS(mtk_spi_slave_runtime_suspend, 549 mtk_spi_slave_runtime_resume, NULL) 550 }; 551 552 static struct platform_driver mtk_spi_slave_driver = { 553 .driver = { 554 .name = "mtk-spi-slave", 555 .pm = &mtk_spi_slave_pm, 556 .of_match_table = mtk_spi_slave_of_match, 557 }, 558 .probe = mtk_spi_slave_probe, 559 .remove = mtk_spi_slave_remove, 560 }; 561 562 module_platform_driver(mtk_spi_slave_driver); 563 564 MODULE_DESCRIPTION("MTK SPI Slave Controller driver"); 565 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>"); 566 MODULE_LICENSE("GPL v2"); 567 MODULE_ALIAS("platform:mtk-spi-slave"); 568