xref: /openbmc/linux/drivers/spi/spi-mt65xx.c (revision 6dfcd296)
1 /*
2  * Copyright (c) 2015 MediaTek Inc.
3  * Author: Leilk Liu <leilk.liu@mediatek.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/device.h>
17 #include <linux/err.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/ioport.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_gpio.h>
24 #include <linux/platform_device.h>
25 #include <linux/platform_data/spi-mt65xx.h>
26 #include <linux/pm_runtime.h>
27 #include <linux/spi/spi.h>
28 
29 #define SPI_CFG0_REG                      0x0000
30 #define SPI_CFG1_REG                      0x0004
31 #define SPI_TX_SRC_REG                    0x0008
32 #define SPI_RX_DST_REG                    0x000c
33 #define SPI_TX_DATA_REG                   0x0010
34 #define SPI_RX_DATA_REG                   0x0014
35 #define SPI_CMD_REG                       0x0018
36 #define SPI_STATUS0_REG                   0x001c
37 #define SPI_PAD_SEL_REG                   0x0024
38 
39 #define SPI_CFG0_SCK_HIGH_OFFSET          0
40 #define SPI_CFG0_SCK_LOW_OFFSET           8
41 #define SPI_CFG0_CS_HOLD_OFFSET           16
42 #define SPI_CFG0_CS_SETUP_OFFSET          24
43 
44 #define SPI_CFG1_CS_IDLE_OFFSET           0
45 #define SPI_CFG1_PACKET_LOOP_OFFSET       8
46 #define SPI_CFG1_PACKET_LENGTH_OFFSET     16
47 #define SPI_CFG1_GET_TICK_DLY_OFFSET      30
48 
49 #define SPI_CFG1_CS_IDLE_MASK             0xff
50 #define SPI_CFG1_PACKET_LOOP_MASK         0xff00
51 #define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
52 
53 #define SPI_CMD_ACT                  BIT(0)
54 #define SPI_CMD_RESUME               BIT(1)
55 #define SPI_CMD_RST                  BIT(2)
56 #define SPI_CMD_PAUSE_EN             BIT(4)
57 #define SPI_CMD_DEASSERT             BIT(5)
58 #define SPI_CMD_CPHA                 BIT(8)
59 #define SPI_CMD_CPOL                 BIT(9)
60 #define SPI_CMD_RX_DMA               BIT(10)
61 #define SPI_CMD_TX_DMA               BIT(11)
62 #define SPI_CMD_TXMSBF               BIT(12)
63 #define SPI_CMD_RXMSBF               BIT(13)
64 #define SPI_CMD_RX_ENDIAN            BIT(14)
65 #define SPI_CMD_TX_ENDIAN            BIT(15)
66 #define SPI_CMD_FINISH_IE            BIT(16)
67 #define SPI_CMD_PAUSE_IE             BIT(17)
68 
69 #define MT8173_SPI_MAX_PAD_SEL 3
70 
71 #define MTK_SPI_PAUSE_INT_STATUS 0x2
72 
73 #define MTK_SPI_IDLE 0
74 #define MTK_SPI_PAUSED 1
75 
76 #define MTK_SPI_MAX_FIFO_SIZE 32
77 #define MTK_SPI_PACKET_SIZE 1024
78 
79 struct mtk_spi_compatible {
80 	bool need_pad_sel;
81 	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
82 	bool must_tx;
83 };
84 
85 struct mtk_spi {
86 	void __iomem *base;
87 	u32 state;
88 	int pad_num;
89 	u32 *pad_sel;
90 	struct clk *parent_clk, *sel_clk, *spi_clk;
91 	struct spi_transfer *cur_transfer;
92 	u32 xfer_len;
93 	struct scatterlist *tx_sgl, *rx_sgl;
94 	u32 tx_sgl_len, rx_sgl_len;
95 	const struct mtk_spi_compatible *dev_comp;
96 };
97 
98 static const struct mtk_spi_compatible mtk_common_compat;
99 static const struct mtk_spi_compatible mt8173_compat = {
100 	.need_pad_sel = true,
101 	.must_tx = true,
102 };
103 
104 /*
105  * A piece of default chip info unless the platform
106  * supplies it.
107  */
108 static const struct mtk_chip_config mtk_default_chip_info = {
109 	.rx_mlsb = 1,
110 	.tx_mlsb = 1,
111 };
112 
113 static const struct of_device_id mtk_spi_of_match[] = {
114 	{ .compatible = "mediatek,mt2701-spi",
115 		.data = (void *)&mtk_common_compat,
116 	},
117 	{ .compatible = "mediatek,mt6589-spi",
118 		.data = (void *)&mtk_common_compat,
119 	},
120 	{ .compatible = "mediatek,mt8135-spi",
121 		.data = (void *)&mtk_common_compat,
122 	},
123 	{ .compatible = "mediatek,mt8173-spi",
124 		.data = (void *)&mt8173_compat,
125 	},
126 	{}
127 };
128 MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
129 
130 static void mtk_spi_reset(struct mtk_spi *mdata)
131 {
132 	u32 reg_val;
133 
134 	/* set the software reset bit in SPI_CMD_REG. */
135 	reg_val = readl(mdata->base + SPI_CMD_REG);
136 	reg_val |= SPI_CMD_RST;
137 	writel(reg_val, mdata->base + SPI_CMD_REG);
138 
139 	reg_val = readl(mdata->base + SPI_CMD_REG);
140 	reg_val &= ~SPI_CMD_RST;
141 	writel(reg_val, mdata->base + SPI_CMD_REG);
142 }
143 
144 static int mtk_spi_prepare_message(struct spi_master *master,
145 				   struct spi_message *msg)
146 {
147 	u16 cpha, cpol;
148 	u32 reg_val;
149 	struct spi_device *spi = msg->spi;
150 	struct mtk_chip_config *chip_config = spi->controller_data;
151 	struct mtk_spi *mdata = spi_master_get_devdata(master);
152 
153 	cpha = spi->mode & SPI_CPHA ? 1 : 0;
154 	cpol = spi->mode & SPI_CPOL ? 1 : 0;
155 
156 	reg_val = readl(mdata->base + SPI_CMD_REG);
157 	if (cpha)
158 		reg_val |= SPI_CMD_CPHA;
159 	else
160 		reg_val &= ~SPI_CMD_CPHA;
161 	if (cpol)
162 		reg_val |= SPI_CMD_CPOL;
163 	else
164 		reg_val &= ~SPI_CMD_CPOL;
165 
166 	/* set the mlsbx and mlsbtx */
167 	if (chip_config->tx_mlsb)
168 		reg_val |= SPI_CMD_TXMSBF;
169 	else
170 		reg_val &= ~SPI_CMD_TXMSBF;
171 	if (chip_config->rx_mlsb)
172 		reg_val |= SPI_CMD_RXMSBF;
173 	else
174 		reg_val &= ~SPI_CMD_RXMSBF;
175 
176 	/* set the tx/rx endian */
177 #ifdef __LITTLE_ENDIAN
178 	reg_val &= ~SPI_CMD_TX_ENDIAN;
179 	reg_val &= ~SPI_CMD_RX_ENDIAN;
180 #else
181 	reg_val |= SPI_CMD_TX_ENDIAN;
182 	reg_val |= SPI_CMD_RX_ENDIAN;
183 #endif
184 
185 	/* set finish and pause interrupt always enable */
186 	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
187 
188 	/* disable dma mode */
189 	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
190 
191 	/* disable deassert mode */
192 	reg_val &= ~SPI_CMD_DEASSERT;
193 
194 	writel(reg_val, mdata->base + SPI_CMD_REG);
195 
196 	/* pad select */
197 	if (mdata->dev_comp->need_pad_sel)
198 		writel(mdata->pad_sel[spi->chip_select],
199 		       mdata->base + SPI_PAD_SEL_REG);
200 
201 	return 0;
202 }
203 
204 static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
205 {
206 	u32 reg_val;
207 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
208 
209 	reg_val = readl(mdata->base + SPI_CMD_REG);
210 	if (!enable) {
211 		reg_val |= SPI_CMD_PAUSE_EN;
212 		writel(reg_val, mdata->base + SPI_CMD_REG);
213 	} else {
214 		reg_val &= ~SPI_CMD_PAUSE_EN;
215 		writel(reg_val, mdata->base + SPI_CMD_REG);
216 		mdata->state = MTK_SPI_IDLE;
217 		mtk_spi_reset(mdata);
218 	}
219 }
220 
221 static void mtk_spi_prepare_transfer(struct spi_master *master,
222 				     struct spi_transfer *xfer)
223 {
224 	u32 spi_clk_hz, div, sck_time, cs_time, reg_val = 0;
225 	struct mtk_spi *mdata = spi_master_get_devdata(master);
226 
227 	spi_clk_hz = clk_get_rate(mdata->spi_clk);
228 	if (xfer->speed_hz < spi_clk_hz / 2)
229 		div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz);
230 	else
231 		div = 1;
232 
233 	sck_time = (div + 1) / 2;
234 	cs_time = sck_time * 2;
235 
236 	reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_HIGH_OFFSET);
237 	reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
238 	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
239 	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
240 	writel(reg_val, mdata->base + SPI_CFG0_REG);
241 
242 	reg_val = readl(mdata->base + SPI_CFG1_REG);
243 	reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
244 	reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
245 	writel(reg_val, mdata->base + SPI_CFG1_REG);
246 }
247 
248 static void mtk_spi_setup_packet(struct spi_master *master)
249 {
250 	u32 packet_size, packet_loop, reg_val;
251 	struct mtk_spi *mdata = spi_master_get_devdata(master);
252 
253 	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
254 	packet_loop = mdata->xfer_len / packet_size;
255 
256 	reg_val = readl(mdata->base + SPI_CFG1_REG);
257 	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
258 	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
259 	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
260 	writel(reg_val, mdata->base + SPI_CFG1_REG);
261 }
262 
263 static void mtk_spi_enable_transfer(struct spi_master *master)
264 {
265 	u32 cmd;
266 	struct mtk_spi *mdata = spi_master_get_devdata(master);
267 
268 	cmd = readl(mdata->base + SPI_CMD_REG);
269 	if (mdata->state == MTK_SPI_IDLE)
270 		cmd |= SPI_CMD_ACT;
271 	else
272 		cmd |= SPI_CMD_RESUME;
273 	writel(cmd, mdata->base + SPI_CMD_REG);
274 }
275 
276 static int mtk_spi_get_mult_delta(u32 xfer_len)
277 {
278 	u32 mult_delta;
279 
280 	if (xfer_len > MTK_SPI_PACKET_SIZE)
281 		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
282 	else
283 		mult_delta = 0;
284 
285 	return mult_delta;
286 }
287 
288 static void mtk_spi_update_mdata_len(struct spi_master *master)
289 {
290 	int mult_delta;
291 	struct mtk_spi *mdata = spi_master_get_devdata(master);
292 
293 	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
294 		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
295 			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
296 			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
297 			mdata->rx_sgl_len = mult_delta;
298 			mdata->tx_sgl_len -= mdata->xfer_len;
299 		} else {
300 			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
301 			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
302 			mdata->tx_sgl_len = mult_delta;
303 			mdata->rx_sgl_len -= mdata->xfer_len;
304 		}
305 	} else if (mdata->tx_sgl_len) {
306 		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
307 		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
308 		mdata->tx_sgl_len = mult_delta;
309 	} else if (mdata->rx_sgl_len) {
310 		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
311 		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
312 		mdata->rx_sgl_len = mult_delta;
313 	}
314 }
315 
316 static void mtk_spi_setup_dma_addr(struct spi_master *master,
317 				   struct spi_transfer *xfer)
318 {
319 	struct mtk_spi *mdata = spi_master_get_devdata(master);
320 
321 	if (mdata->tx_sgl)
322 		writel(xfer->tx_dma, mdata->base + SPI_TX_SRC_REG);
323 	if (mdata->rx_sgl)
324 		writel(xfer->rx_dma, mdata->base + SPI_RX_DST_REG);
325 }
326 
327 static int mtk_spi_fifo_transfer(struct spi_master *master,
328 				 struct spi_device *spi,
329 				 struct spi_transfer *xfer)
330 {
331 	int cnt, remainder;
332 	u32 reg_val;
333 	struct mtk_spi *mdata = spi_master_get_devdata(master);
334 
335 	mdata->cur_transfer = xfer;
336 	mdata->xfer_len = xfer->len;
337 	mtk_spi_prepare_transfer(master, xfer);
338 	mtk_spi_setup_packet(master);
339 
340 	cnt = xfer->len / 4;
341 	iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
342 
343 	remainder = xfer->len % 4;
344 	if (remainder > 0) {
345 		reg_val = 0;
346 		memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
347 		writel(reg_val, mdata->base + SPI_TX_DATA_REG);
348 	}
349 
350 	mtk_spi_enable_transfer(master);
351 
352 	return 1;
353 }
354 
355 static int mtk_spi_dma_transfer(struct spi_master *master,
356 				struct spi_device *spi,
357 				struct spi_transfer *xfer)
358 {
359 	int cmd;
360 	struct mtk_spi *mdata = spi_master_get_devdata(master);
361 
362 	mdata->tx_sgl = NULL;
363 	mdata->rx_sgl = NULL;
364 	mdata->tx_sgl_len = 0;
365 	mdata->rx_sgl_len = 0;
366 	mdata->cur_transfer = xfer;
367 
368 	mtk_spi_prepare_transfer(master, xfer);
369 
370 	cmd = readl(mdata->base + SPI_CMD_REG);
371 	if (xfer->tx_buf)
372 		cmd |= SPI_CMD_TX_DMA;
373 	if (xfer->rx_buf)
374 		cmd |= SPI_CMD_RX_DMA;
375 	writel(cmd, mdata->base + SPI_CMD_REG);
376 
377 	if (xfer->tx_buf)
378 		mdata->tx_sgl = xfer->tx_sg.sgl;
379 	if (xfer->rx_buf)
380 		mdata->rx_sgl = xfer->rx_sg.sgl;
381 
382 	if (mdata->tx_sgl) {
383 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
384 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
385 	}
386 	if (mdata->rx_sgl) {
387 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
388 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
389 	}
390 
391 	mtk_spi_update_mdata_len(master);
392 	mtk_spi_setup_packet(master);
393 	mtk_spi_setup_dma_addr(master, xfer);
394 	mtk_spi_enable_transfer(master);
395 
396 	return 1;
397 }
398 
399 static int mtk_spi_transfer_one(struct spi_master *master,
400 				struct spi_device *spi,
401 				struct spi_transfer *xfer)
402 {
403 	if (master->can_dma(master, spi, xfer))
404 		return mtk_spi_dma_transfer(master, spi, xfer);
405 	else
406 		return mtk_spi_fifo_transfer(master, spi, xfer);
407 }
408 
409 static bool mtk_spi_can_dma(struct spi_master *master,
410 			    struct spi_device *spi,
411 			    struct spi_transfer *xfer)
412 {
413 	return xfer->len > MTK_SPI_MAX_FIFO_SIZE;
414 }
415 
416 static int mtk_spi_setup(struct spi_device *spi)
417 {
418 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
419 
420 	if (!spi->controller_data)
421 		spi->controller_data = (void *)&mtk_default_chip_info;
422 
423 	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
424 		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
425 
426 	return 0;
427 }
428 
429 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
430 {
431 	u32 cmd, reg_val, cnt, remainder;
432 	struct spi_master *master = dev_id;
433 	struct mtk_spi *mdata = spi_master_get_devdata(master);
434 	struct spi_transfer *trans = mdata->cur_transfer;
435 
436 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
437 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
438 		mdata->state = MTK_SPI_PAUSED;
439 	else
440 		mdata->state = MTK_SPI_IDLE;
441 
442 	if (!master->can_dma(master, master->cur_msg->spi, trans)) {
443 		if (trans->rx_buf) {
444 			cnt = mdata->xfer_len / 4;
445 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
446 				     trans->rx_buf, cnt);
447 			remainder = mdata->xfer_len % 4;
448 			if (remainder > 0) {
449 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
450 				memcpy(trans->rx_buf + (cnt * 4),
451 					&reg_val, remainder);
452 			}
453 		}
454 		spi_finalize_current_transfer(master);
455 		return IRQ_HANDLED;
456 	}
457 
458 	if (mdata->tx_sgl)
459 		trans->tx_dma += mdata->xfer_len;
460 	if (mdata->rx_sgl)
461 		trans->rx_dma += mdata->xfer_len;
462 
463 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
464 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
465 		if (mdata->tx_sgl) {
466 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
467 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
468 		}
469 	}
470 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
471 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
472 		if (mdata->rx_sgl) {
473 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
474 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
475 		}
476 	}
477 
478 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
479 		/* spi disable dma */
480 		cmd = readl(mdata->base + SPI_CMD_REG);
481 		cmd &= ~SPI_CMD_TX_DMA;
482 		cmd &= ~SPI_CMD_RX_DMA;
483 		writel(cmd, mdata->base + SPI_CMD_REG);
484 
485 		spi_finalize_current_transfer(master);
486 		return IRQ_HANDLED;
487 	}
488 
489 	mtk_spi_update_mdata_len(master);
490 	mtk_spi_setup_packet(master);
491 	mtk_spi_setup_dma_addr(master, trans);
492 	mtk_spi_enable_transfer(master);
493 
494 	return IRQ_HANDLED;
495 }
496 
497 static int mtk_spi_probe(struct platform_device *pdev)
498 {
499 	struct spi_master *master;
500 	struct mtk_spi *mdata;
501 	const struct of_device_id *of_id;
502 	struct resource *res;
503 	int i, irq, ret;
504 
505 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
506 	if (!master) {
507 		dev_err(&pdev->dev, "failed to alloc spi master\n");
508 		return -ENOMEM;
509 	}
510 
511 	master->auto_runtime_pm = true;
512 	master->dev.of_node = pdev->dev.of_node;
513 	master->mode_bits = SPI_CPOL | SPI_CPHA;
514 
515 	master->set_cs = mtk_spi_set_cs;
516 	master->prepare_message = mtk_spi_prepare_message;
517 	master->transfer_one = mtk_spi_transfer_one;
518 	master->can_dma = mtk_spi_can_dma;
519 	master->setup = mtk_spi_setup;
520 
521 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
522 	if (!of_id) {
523 		dev_err(&pdev->dev, "failed to probe of_node\n");
524 		ret = -EINVAL;
525 		goto err_put_master;
526 	}
527 
528 	mdata = spi_master_get_devdata(master);
529 	mdata->dev_comp = of_id->data;
530 	if (mdata->dev_comp->must_tx)
531 		master->flags = SPI_MASTER_MUST_TX;
532 
533 	if (mdata->dev_comp->need_pad_sel) {
534 		mdata->pad_num = of_property_count_u32_elems(
535 			pdev->dev.of_node,
536 			"mediatek,pad-select");
537 		if (mdata->pad_num < 0) {
538 			dev_err(&pdev->dev,
539 				"No 'mediatek,pad-select' property\n");
540 			ret = -EINVAL;
541 			goto err_put_master;
542 		}
543 
544 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
545 						    sizeof(u32), GFP_KERNEL);
546 		if (!mdata->pad_sel) {
547 			ret = -ENOMEM;
548 			goto err_put_master;
549 		}
550 
551 		for (i = 0; i < mdata->pad_num; i++) {
552 			of_property_read_u32_index(pdev->dev.of_node,
553 						   "mediatek,pad-select",
554 						   i, &mdata->pad_sel[i]);
555 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
556 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
557 					i, mdata->pad_sel[i]);
558 				ret = -EINVAL;
559 				goto err_put_master;
560 			}
561 		}
562 	}
563 
564 	platform_set_drvdata(pdev, master);
565 
566 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
567 	if (!res) {
568 		ret = -ENODEV;
569 		dev_err(&pdev->dev, "failed to determine base address\n");
570 		goto err_put_master;
571 	}
572 
573 	mdata->base = devm_ioremap_resource(&pdev->dev, res);
574 	if (IS_ERR(mdata->base)) {
575 		ret = PTR_ERR(mdata->base);
576 		goto err_put_master;
577 	}
578 
579 	irq = platform_get_irq(pdev, 0);
580 	if (irq < 0) {
581 		dev_err(&pdev->dev, "failed to get irq (%d)\n", irq);
582 		ret = irq;
583 		goto err_put_master;
584 	}
585 
586 	if (!pdev->dev.dma_mask)
587 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
588 
589 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
590 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
591 	if (ret) {
592 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
593 		goto err_put_master;
594 	}
595 
596 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
597 	if (IS_ERR(mdata->parent_clk)) {
598 		ret = PTR_ERR(mdata->parent_clk);
599 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
600 		goto err_put_master;
601 	}
602 
603 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
604 	if (IS_ERR(mdata->sel_clk)) {
605 		ret = PTR_ERR(mdata->sel_clk);
606 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
607 		goto err_put_master;
608 	}
609 
610 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
611 	if (IS_ERR(mdata->spi_clk)) {
612 		ret = PTR_ERR(mdata->spi_clk);
613 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
614 		goto err_put_master;
615 	}
616 
617 	ret = clk_prepare_enable(mdata->spi_clk);
618 	if (ret < 0) {
619 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
620 		goto err_put_master;
621 	}
622 
623 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
624 	if (ret < 0) {
625 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
626 		clk_disable_unprepare(mdata->spi_clk);
627 		goto err_put_master;
628 	}
629 
630 	clk_disable_unprepare(mdata->spi_clk);
631 
632 	pm_runtime_enable(&pdev->dev);
633 
634 	ret = devm_spi_register_master(&pdev->dev, master);
635 	if (ret) {
636 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
637 		goto err_disable_runtime_pm;
638 	}
639 
640 	if (mdata->dev_comp->need_pad_sel) {
641 		if (mdata->pad_num != master->num_chipselect) {
642 			dev_err(&pdev->dev,
643 				"pad_num does not match num_chipselect(%d != %d)\n",
644 				mdata->pad_num, master->num_chipselect);
645 			ret = -EINVAL;
646 			goto err_disable_runtime_pm;
647 		}
648 
649 		if (!master->cs_gpios && master->num_chipselect > 1) {
650 			dev_err(&pdev->dev,
651 				"cs_gpios not specified and num_chipselect > 1\n");
652 			ret = -EINVAL;
653 			goto err_disable_runtime_pm;
654 		}
655 
656 		if (master->cs_gpios) {
657 			for (i = 0; i < master->num_chipselect; i++) {
658 				ret = devm_gpio_request(&pdev->dev,
659 							master->cs_gpios[i],
660 							dev_name(&pdev->dev));
661 				if (ret) {
662 					dev_err(&pdev->dev,
663 						"can't get CS GPIO %i\n", i);
664 					goto err_disable_runtime_pm;
665 				}
666 			}
667 		}
668 	}
669 
670 	return 0;
671 
672 err_disable_runtime_pm:
673 	pm_runtime_disable(&pdev->dev);
674 err_put_master:
675 	spi_master_put(master);
676 
677 	return ret;
678 }
679 
680 static int mtk_spi_remove(struct platform_device *pdev)
681 {
682 	struct spi_master *master = platform_get_drvdata(pdev);
683 	struct mtk_spi *mdata = spi_master_get_devdata(master);
684 
685 	pm_runtime_disable(&pdev->dev);
686 
687 	mtk_spi_reset(mdata);
688 
689 	return 0;
690 }
691 
692 #ifdef CONFIG_PM_SLEEP
693 static int mtk_spi_suspend(struct device *dev)
694 {
695 	int ret;
696 	struct spi_master *master = dev_get_drvdata(dev);
697 	struct mtk_spi *mdata = spi_master_get_devdata(master);
698 
699 	ret = spi_master_suspend(master);
700 	if (ret)
701 		return ret;
702 
703 	if (!pm_runtime_suspended(dev))
704 		clk_disable_unprepare(mdata->spi_clk);
705 
706 	return ret;
707 }
708 
709 static int mtk_spi_resume(struct device *dev)
710 {
711 	int ret;
712 	struct spi_master *master = dev_get_drvdata(dev);
713 	struct mtk_spi *mdata = spi_master_get_devdata(master);
714 
715 	if (!pm_runtime_suspended(dev)) {
716 		ret = clk_prepare_enable(mdata->spi_clk);
717 		if (ret < 0) {
718 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
719 			return ret;
720 		}
721 	}
722 
723 	ret = spi_master_resume(master);
724 	if (ret < 0)
725 		clk_disable_unprepare(mdata->spi_clk);
726 
727 	return ret;
728 }
729 #endif /* CONFIG_PM_SLEEP */
730 
731 #ifdef CONFIG_PM
732 static int mtk_spi_runtime_suspend(struct device *dev)
733 {
734 	struct spi_master *master = dev_get_drvdata(dev);
735 	struct mtk_spi *mdata = spi_master_get_devdata(master);
736 
737 	clk_disable_unprepare(mdata->spi_clk);
738 
739 	return 0;
740 }
741 
742 static int mtk_spi_runtime_resume(struct device *dev)
743 {
744 	struct spi_master *master = dev_get_drvdata(dev);
745 	struct mtk_spi *mdata = spi_master_get_devdata(master);
746 	int ret;
747 
748 	ret = clk_prepare_enable(mdata->spi_clk);
749 	if (ret < 0) {
750 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
751 		return ret;
752 	}
753 
754 	return 0;
755 }
756 #endif /* CONFIG_PM */
757 
758 static const struct dev_pm_ops mtk_spi_pm = {
759 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
760 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
761 			   mtk_spi_runtime_resume, NULL)
762 };
763 
764 static struct platform_driver mtk_spi_driver = {
765 	.driver = {
766 		.name = "mtk-spi",
767 		.pm	= &mtk_spi_pm,
768 		.of_match_table = mtk_spi_of_match,
769 	},
770 	.probe = mtk_spi_probe,
771 	.remove = mtk_spi_remove,
772 };
773 
774 module_platform_driver(mtk_spi_driver);
775 
776 MODULE_DESCRIPTION("MTK SPI Controller driver");
777 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
778 MODULE_LICENSE("GPL v2");
779 MODULE_ALIAS("platform:mtk-spi");
780