xref: /linux/drivers/spi/spi-mt65xx.c (revision 6c363eafc4d637ac4bd83d4a7dd06dd3cfbe7c5f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015 MediaTek Inc.
4  * Author: Leilk Liu <leilk.liu@mediatek.com>
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/device.h>
9 #include <linux/err.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/ioport.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_gpio.h>
16 #include <linux/platform_device.h>
17 #include <linux/platform_data/spi-mt65xx.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/spi/spi.h>
20 #include <linux/dma-mapping.h>
21 
22 #define SPI_CFG0_REG                      0x0000
23 #define SPI_CFG1_REG                      0x0004
24 #define SPI_TX_SRC_REG                    0x0008
25 #define SPI_RX_DST_REG                    0x000c
26 #define SPI_TX_DATA_REG                   0x0010
27 #define SPI_RX_DATA_REG                   0x0014
28 #define SPI_CMD_REG                       0x0018
29 #define SPI_STATUS0_REG                   0x001c
30 #define SPI_PAD_SEL_REG                   0x0024
31 #define SPI_CFG2_REG                      0x0028
32 #define SPI_TX_SRC_REG_64                 0x002c
33 #define SPI_RX_DST_REG_64                 0x0030
34 
35 #define SPI_CFG0_SCK_HIGH_OFFSET          0
36 #define SPI_CFG0_SCK_LOW_OFFSET           8
37 #define SPI_CFG0_CS_HOLD_OFFSET           16
38 #define SPI_CFG0_CS_SETUP_OFFSET          24
39 #define SPI_ADJUST_CFG0_CS_HOLD_OFFSET    0
40 #define SPI_ADJUST_CFG0_CS_SETUP_OFFSET   16
41 
42 #define SPI_CFG1_CS_IDLE_OFFSET           0
43 #define SPI_CFG1_PACKET_LOOP_OFFSET       8
44 #define SPI_CFG1_PACKET_LENGTH_OFFSET     16
45 #define SPI_CFG1_GET_TICK_DLY_OFFSET      30
46 
47 #define SPI_CFG1_CS_IDLE_MASK             0xff
48 #define SPI_CFG1_PACKET_LOOP_MASK         0xff00
49 #define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
50 #define SPI_CFG2_SCK_HIGH_OFFSET          0
51 #define SPI_CFG2_SCK_LOW_OFFSET           16
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_SAMPLE_SEL           BIT(6)
59 #define SPI_CMD_CS_POL               BIT(7)
60 #define SPI_CMD_CPHA                 BIT(8)
61 #define SPI_CMD_CPOL                 BIT(9)
62 #define SPI_CMD_RX_DMA               BIT(10)
63 #define SPI_CMD_TX_DMA               BIT(11)
64 #define SPI_CMD_TXMSBF               BIT(12)
65 #define SPI_CMD_RXMSBF               BIT(13)
66 #define SPI_CMD_RX_ENDIAN            BIT(14)
67 #define SPI_CMD_TX_ENDIAN            BIT(15)
68 #define SPI_CMD_FINISH_IE            BIT(16)
69 #define SPI_CMD_PAUSE_IE             BIT(17)
70 
71 #define MT8173_SPI_MAX_PAD_SEL 3
72 
73 #define MTK_SPI_PAUSE_INT_STATUS 0x2
74 
75 #define MTK_SPI_IDLE 0
76 #define MTK_SPI_PAUSED 1
77 
78 #define MTK_SPI_MAX_FIFO_SIZE 32U
79 #define MTK_SPI_PACKET_SIZE 1024
80 #define MTK_SPI_32BITS_MASK  (0xffffffff)
81 
82 #define DMA_ADDR_EXT_BITS (36)
83 #define DMA_ADDR_DEF_BITS (32)
84 
85 struct mtk_spi_compatible {
86 	bool need_pad_sel;
87 	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
88 	bool must_tx;
89 	/* some IC design adjust cfg register to enhance time accuracy */
90 	bool enhance_timing;
91 	/* some IC support DMA addr extension */
92 	bool dma_ext;
93 };
94 
95 struct mtk_spi {
96 	void __iomem *base;
97 	u32 state;
98 	int pad_num;
99 	u32 *pad_sel;
100 	struct clk *parent_clk, *sel_clk, *spi_clk;
101 	struct spi_transfer *cur_transfer;
102 	u32 xfer_len;
103 	u32 num_xfered;
104 	struct scatterlist *tx_sgl, *rx_sgl;
105 	u32 tx_sgl_len, rx_sgl_len;
106 	const struct mtk_spi_compatible *dev_comp;
107 };
108 
109 static const struct mtk_spi_compatible mtk_common_compat;
110 
111 static const struct mtk_spi_compatible mt2712_compat = {
112 	.must_tx = true,
113 };
114 
115 static const struct mtk_spi_compatible mt6765_compat = {
116 	.need_pad_sel = true,
117 	.must_tx = true,
118 	.enhance_timing = true,
119 	.dma_ext = true,
120 };
121 
122 static const struct mtk_spi_compatible mt7622_compat = {
123 	.must_tx = true,
124 	.enhance_timing = true,
125 };
126 
127 static const struct mtk_spi_compatible mt8173_compat = {
128 	.need_pad_sel = true,
129 	.must_tx = true,
130 };
131 
132 static const struct mtk_spi_compatible mt8183_compat = {
133 	.need_pad_sel = true,
134 	.must_tx = true,
135 	.enhance_timing = true,
136 };
137 
138 /*
139  * A piece of default chip info unless the platform
140  * supplies it.
141  */
142 static const struct mtk_chip_config mtk_default_chip_info = {
143 	.sample_sel = 0,
144 };
145 
146 static const struct of_device_id mtk_spi_of_match[] = {
147 	{ .compatible = "mediatek,mt2701-spi",
148 		.data = (void *)&mtk_common_compat,
149 	},
150 	{ .compatible = "mediatek,mt2712-spi",
151 		.data = (void *)&mt2712_compat,
152 	},
153 	{ .compatible = "mediatek,mt6589-spi",
154 		.data = (void *)&mtk_common_compat,
155 	},
156 	{ .compatible = "mediatek,mt6765-spi",
157 		.data = (void *)&mt6765_compat,
158 	},
159 	{ .compatible = "mediatek,mt7622-spi",
160 		.data = (void *)&mt7622_compat,
161 	},
162 	{ .compatible = "mediatek,mt7629-spi",
163 		.data = (void *)&mt7622_compat,
164 	},
165 	{ .compatible = "mediatek,mt8135-spi",
166 		.data = (void *)&mtk_common_compat,
167 	},
168 	{ .compatible = "mediatek,mt8173-spi",
169 		.data = (void *)&mt8173_compat,
170 	},
171 	{ .compatible = "mediatek,mt8183-spi",
172 		.data = (void *)&mt8183_compat,
173 	},
174 	{ .compatible = "mediatek,mt8192-spi",
175 		.data = (void *)&mt6765_compat,
176 	},
177 	{}
178 };
179 MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
180 
181 static void mtk_spi_reset(struct mtk_spi *mdata)
182 {
183 	u32 reg_val;
184 
185 	/* set the software reset bit in SPI_CMD_REG. */
186 	reg_val = readl(mdata->base + SPI_CMD_REG);
187 	reg_val |= SPI_CMD_RST;
188 	writel(reg_val, mdata->base + SPI_CMD_REG);
189 
190 	reg_val = readl(mdata->base + SPI_CMD_REG);
191 	reg_val &= ~SPI_CMD_RST;
192 	writel(reg_val, mdata->base + SPI_CMD_REG);
193 }
194 
195 static int mtk_spi_prepare_message(struct spi_master *master,
196 				   struct spi_message *msg)
197 {
198 	u16 cpha, cpol;
199 	u32 reg_val;
200 	struct spi_device *spi = msg->spi;
201 	struct mtk_chip_config *chip_config = spi->controller_data;
202 	struct mtk_spi *mdata = spi_master_get_devdata(master);
203 
204 	cpha = spi->mode & SPI_CPHA ? 1 : 0;
205 	cpol = spi->mode & SPI_CPOL ? 1 : 0;
206 
207 	reg_val = readl(mdata->base + SPI_CMD_REG);
208 	if (cpha)
209 		reg_val |= SPI_CMD_CPHA;
210 	else
211 		reg_val &= ~SPI_CMD_CPHA;
212 	if (cpol)
213 		reg_val |= SPI_CMD_CPOL;
214 	else
215 		reg_val &= ~SPI_CMD_CPOL;
216 
217 	/* set the mlsbx and mlsbtx */
218 	if (spi->mode & SPI_LSB_FIRST) {
219 		reg_val &= ~SPI_CMD_TXMSBF;
220 		reg_val &= ~SPI_CMD_RXMSBF;
221 	} else {
222 		reg_val |= SPI_CMD_TXMSBF;
223 		reg_val |= SPI_CMD_RXMSBF;
224 	}
225 
226 	/* set the tx/rx endian */
227 #ifdef __LITTLE_ENDIAN
228 	reg_val &= ~SPI_CMD_TX_ENDIAN;
229 	reg_val &= ~SPI_CMD_RX_ENDIAN;
230 #else
231 	reg_val |= SPI_CMD_TX_ENDIAN;
232 	reg_val |= SPI_CMD_RX_ENDIAN;
233 #endif
234 
235 	if (mdata->dev_comp->enhance_timing) {
236 		/* set CS polarity */
237 		if (spi->mode & SPI_CS_HIGH)
238 			reg_val |= SPI_CMD_CS_POL;
239 		else
240 			reg_val &= ~SPI_CMD_CS_POL;
241 
242 		if (chip_config->sample_sel)
243 			reg_val |= SPI_CMD_SAMPLE_SEL;
244 		else
245 			reg_val &= ~SPI_CMD_SAMPLE_SEL;
246 	}
247 
248 	/* set finish and pause interrupt always enable */
249 	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
250 
251 	/* disable dma mode */
252 	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
253 
254 	/* disable deassert mode */
255 	reg_val &= ~SPI_CMD_DEASSERT;
256 
257 	writel(reg_val, mdata->base + SPI_CMD_REG);
258 
259 	/* pad select */
260 	if (mdata->dev_comp->need_pad_sel)
261 		writel(mdata->pad_sel[spi->chip_select],
262 		       mdata->base + SPI_PAD_SEL_REG);
263 
264 	return 0;
265 }
266 
267 static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
268 {
269 	u32 reg_val;
270 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
271 
272 	if (spi->mode & SPI_CS_HIGH)
273 		enable = !enable;
274 
275 	reg_val = readl(mdata->base + SPI_CMD_REG);
276 	if (!enable) {
277 		reg_val |= SPI_CMD_PAUSE_EN;
278 		writel(reg_val, mdata->base + SPI_CMD_REG);
279 	} else {
280 		reg_val &= ~SPI_CMD_PAUSE_EN;
281 		writel(reg_val, mdata->base + SPI_CMD_REG);
282 		mdata->state = MTK_SPI_IDLE;
283 		mtk_spi_reset(mdata);
284 	}
285 }
286 
287 static void mtk_spi_prepare_transfer(struct spi_master *master,
288 				     struct spi_transfer *xfer)
289 {
290 	u32 spi_clk_hz, div, sck_time, reg_val;
291 	struct mtk_spi *mdata = spi_master_get_devdata(master);
292 
293 	spi_clk_hz = clk_get_rate(mdata->spi_clk);
294 	if (xfer->speed_hz < spi_clk_hz / 2)
295 		div = DIV_ROUND_UP(spi_clk_hz, xfer->speed_hz);
296 	else
297 		div = 1;
298 
299 	sck_time = (div + 1) / 2;
300 
301 	if (mdata->dev_comp->enhance_timing) {
302 		reg_val = readl(mdata->base + SPI_CFG2_REG);
303 		reg_val &= ~(0xffff << SPI_CFG2_SCK_HIGH_OFFSET);
304 		reg_val |= (((sck_time - 1) & 0xffff)
305 			   << SPI_CFG2_SCK_HIGH_OFFSET);
306 		reg_val &= ~(0xffff << SPI_CFG2_SCK_LOW_OFFSET);
307 		reg_val |= (((sck_time - 1) & 0xffff)
308 			   << SPI_CFG2_SCK_LOW_OFFSET);
309 		writel(reg_val, mdata->base + SPI_CFG2_REG);
310 	} else {
311 		reg_val = readl(mdata->base + SPI_CFG0_REG);
312 		reg_val &= ~(0xff << SPI_CFG0_SCK_HIGH_OFFSET);
313 		reg_val |= (((sck_time - 1) & 0xff)
314 			   << SPI_CFG0_SCK_HIGH_OFFSET);
315 		reg_val &= ~(0xff << SPI_CFG0_SCK_LOW_OFFSET);
316 		reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
317 		writel(reg_val, mdata->base + SPI_CFG0_REG);
318 	}
319 }
320 
321 static void mtk_spi_setup_packet(struct spi_master *master)
322 {
323 	u32 packet_size, packet_loop, reg_val;
324 	struct mtk_spi *mdata = spi_master_get_devdata(master);
325 
326 	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
327 	packet_loop = mdata->xfer_len / packet_size;
328 
329 	reg_val = readl(mdata->base + SPI_CFG1_REG);
330 	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
331 	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
332 	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
333 	writel(reg_val, mdata->base + SPI_CFG1_REG);
334 }
335 
336 static void mtk_spi_enable_transfer(struct spi_master *master)
337 {
338 	u32 cmd;
339 	struct mtk_spi *mdata = spi_master_get_devdata(master);
340 
341 	cmd = readl(mdata->base + SPI_CMD_REG);
342 	if (mdata->state == MTK_SPI_IDLE)
343 		cmd |= SPI_CMD_ACT;
344 	else
345 		cmd |= SPI_CMD_RESUME;
346 	writel(cmd, mdata->base + SPI_CMD_REG);
347 }
348 
349 static int mtk_spi_get_mult_delta(u32 xfer_len)
350 {
351 	u32 mult_delta;
352 
353 	if (xfer_len > MTK_SPI_PACKET_SIZE)
354 		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
355 	else
356 		mult_delta = 0;
357 
358 	return mult_delta;
359 }
360 
361 static void mtk_spi_update_mdata_len(struct spi_master *master)
362 {
363 	int mult_delta;
364 	struct mtk_spi *mdata = spi_master_get_devdata(master);
365 
366 	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
367 		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
368 			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
369 			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
370 			mdata->rx_sgl_len = mult_delta;
371 			mdata->tx_sgl_len -= mdata->xfer_len;
372 		} else {
373 			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
374 			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
375 			mdata->tx_sgl_len = mult_delta;
376 			mdata->rx_sgl_len -= mdata->xfer_len;
377 		}
378 	} else if (mdata->tx_sgl_len) {
379 		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
380 		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
381 		mdata->tx_sgl_len = mult_delta;
382 	} else if (mdata->rx_sgl_len) {
383 		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
384 		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
385 		mdata->rx_sgl_len = mult_delta;
386 	}
387 }
388 
389 static void mtk_spi_setup_dma_addr(struct spi_master *master,
390 				   struct spi_transfer *xfer)
391 {
392 	struct mtk_spi *mdata = spi_master_get_devdata(master);
393 
394 	if (mdata->tx_sgl) {
395 		writel((u32)(xfer->tx_dma & MTK_SPI_32BITS_MASK),
396 		       mdata->base + SPI_TX_SRC_REG);
397 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
398 		if (mdata->dev_comp->dma_ext)
399 			writel((u32)(xfer->tx_dma >> 32),
400 			       mdata->base + SPI_TX_SRC_REG_64);
401 #endif
402 	}
403 
404 	if (mdata->rx_sgl) {
405 		writel((u32)(xfer->rx_dma & MTK_SPI_32BITS_MASK),
406 		       mdata->base + SPI_RX_DST_REG);
407 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
408 		if (mdata->dev_comp->dma_ext)
409 			writel((u32)(xfer->rx_dma >> 32),
410 			       mdata->base + SPI_RX_DST_REG_64);
411 #endif
412 	}
413 }
414 
415 static int mtk_spi_fifo_transfer(struct spi_master *master,
416 				 struct spi_device *spi,
417 				 struct spi_transfer *xfer)
418 {
419 	int cnt, remainder;
420 	u32 reg_val;
421 	struct mtk_spi *mdata = spi_master_get_devdata(master);
422 
423 	mdata->cur_transfer = xfer;
424 	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
425 	mdata->num_xfered = 0;
426 	mtk_spi_prepare_transfer(master, xfer);
427 	mtk_spi_setup_packet(master);
428 
429 	cnt = xfer->len / 4;
430 	iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
431 
432 	remainder = xfer->len % 4;
433 	if (remainder > 0) {
434 		reg_val = 0;
435 		memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
436 		writel(reg_val, mdata->base + SPI_TX_DATA_REG);
437 	}
438 
439 	mtk_spi_enable_transfer(master);
440 
441 	return 1;
442 }
443 
444 static int mtk_spi_dma_transfer(struct spi_master *master,
445 				struct spi_device *spi,
446 				struct spi_transfer *xfer)
447 {
448 	int cmd;
449 	struct mtk_spi *mdata = spi_master_get_devdata(master);
450 
451 	mdata->tx_sgl = NULL;
452 	mdata->rx_sgl = NULL;
453 	mdata->tx_sgl_len = 0;
454 	mdata->rx_sgl_len = 0;
455 	mdata->cur_transfer = xfer;
456 	mdata->num_xfered = 0;
457 
458 	mtk_spi_prepare_transfer(master, xfer);
459 
460 	cmd = readl(mdata->base + SPI_CMD_REG);
461 	if (xfer->tx_buf)
462 		cmd |= SPI_CMD_TX_DMA;
463 	if (xfer->rx_buf)
464 		cmd |= SPI_CMD_RX_DMA;
465 	writel(cmd, mdata->base + SPI_CMD_REG);
466 
467 	if (xfer->tx_buf)
468 		mdata->tx_sgl = xfer->tx_sg.sgl;
469 	if (xfer->rx_buf)
470 		mdata->rx_sgl = xfer->rx_sg.sgl;
471 
472 	if (mdata->tx_sgl) {
473 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
474 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
475 	}
476 	if (mdata->rx_sgl) {
477 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
478 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
479 	}
480 
481 	mtk_spi_update_mdata_len(master);
482 	mtk_spi_setup_packet(master);
483 	mtk_spi_setup_dma_addr(master, xfer);
484 	mtk_spi_enable_transfer(master);
485 
486 	return 1;
487 }
488 
489 static int mtk_spi_transfer_one(struct spi_master *master,
490 				struct spi_device *spi,
491 				struct spi_transfer *xfer)
492 {
493 	if (master->can_dma(master, spi, xfer))
494 		return mtk_spi_dma_transfer(master, spi, xfer);
495 	else
496 		return mtk_spi_fifo_transfer(master, spi, xfer);
497 }
498 
499 static bool mtk_spi_can_dma(struct spi_master *master,
500 			    struct spi_device *spi,
501 			    struct spi_transfer *xfer)
502 {
503 	/* Buffers for DMA transactions must be 4-byte aligned */
504 	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
505 		(unsigned long)xfer->tx_buf % 4 == 0 &&
506 		(unsigned long)xfer->rx_buf % 4 == 0);
507 }
508 
509 static int mtk_spi_set_hw_cs_timing(struct spi_device *spi,
510 				    struct spi_delay *setup,
511 				    struct spi_delay *hold,
512 				    struct spi_delay *inactive)
513 {
514 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
515 	u16 setup_dly, hold_dly, inactive_dly;
516 	u32 reg_val;
517 
518 	if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) ||
519 	    (hold && hold->unit != SPI_DELAY_UNIT_SCK) ||
520 	    (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) {
521 		dev_err(&spi->dev,
522 			"Invalid delay unit, should be SPI_DELAY_UNIT_SCK\n");
523 		return -EINVAL;
524 	}
525 
526 	setup_dly = setup ? setup->value : 1;
527 	hold_dly = hold ? hold->value : 1;
528 	inactive_dly = inactive ? inactive->value : 1;
529 
530 	reg_val = readl(mdata->base + SPI_CFG0_REG);
531 	if (mdata->dev_comp->enhance_timing) {
532 		reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
533 		reg_val |= (((hold_dly - 1) & 0xffff)
534 			   << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
535 		reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
536 		reg_val |= (((setup_dly - 1) & 0xffff)
537 			   << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
538 	} else {
539 		reg_val &= ~(0xff << SPI_CFG0_CS_HOLD_OFFSET);
540 		reg_val |= (((hold_dly - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
541 		reg_val &= ~(0xff << SPI_CFG0_CS_SETUP_OFFSET);
542 		reg_val |= (((setup_dly - 1) & 0xff)
543 			    << SPI_CFG0_CS_SETUP_OFFSET);
544 	}
545 	writel(reg_val, mdata->base + SPI_CFG0_REG);
546 
547 	reg_val = readl(mdata->base + SPI_CFG1_REG);
548 	reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
549 	reg_val |= (((inactive_dly - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
550 	writel(reg_val, mdata->base + SPI_CFG1_REG);
551 
552 	return 0;
553 }
554 
555 static int mtk_spi_setup(struct spi_device *spi)
556 {
557 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
558 
559 	if (!spi->controller_data)
560 		spi->controller_data = (void *)&mtk_default_chip_info;
561 
562 	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
563 		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
564 
565 	return 0;
566 }
567 
568 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
569 {
570 	u32 cmd, reg_val, cnt, remainder, len;
571 	struct spi_master *master = dev_id;
572 	struct mtk_spi *mdata = spi_master_get_devdata(master);
573 	struct spi_transfer *trans = mdata->cur_transfer;
574 
575 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
576 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
577 		mdata->state = MTK_SPI_PAUSED;
578 	else
579 		mdata->state = MTK_SPI_IDLE;
580 
581 	if (!master->can_dma(master, master->cur_msg->spi, trans)) {
582 		if (trans->rx_buf) {
583 			cnt = mdata->xfer_len / 4;
584 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
585 				     trans->rx_buf + mdata->num_xfered, cnt);
586 			remainder = mdata->xfer_len % 4;
587 			if (remainder > 0) {
588 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
589 				memcpy(trans->rx_buf +
590 					mdata->num_xfered +
591 					(cnt * 4),
592 					&reg_val,
593 					remainder);
594 			}
595 		}
596 
597 		mdata->num_xfered += mdata->xfer_len;
598 		if (mdata->num_xfered == trans->len) {
599 			spi_finalize_current_transfer(master);
600 			return IRQ_HANDLED;
601 		}
602 
603 		len = trans->len - mdata->num_xfered;
604 		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
605 		mtk_spi_setup_packet(master);
606 
607 		cnt = mdata->xfer_len / 4;
608 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
609 				trans->tx_buf + mdata->num_xfered, cnt);
610 
611 		remainder = mdata->xfer_len % 4;
612 		if (remainder > 0) {
613 			reg_val = 0;
614 			memcpy(&reg_val,
615 				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
616 				remainder);
617 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
618 		}
619 
620 		mtk_spi_enable_transfer(master);
621 
622 		return IRQ_HANDLED;
623 	}
624 
625 	if (mdata->tx_sgl)
626 		trans->tx_dma += mdata->xfer_len;
627 	if (mdata->rx_sgl)
628 		trans->rx_dma += mdata->xfer_len;
629 
630 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
631 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
632 		if (mdata->tx_sgl) {
633 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
634 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
635 		}
636 	}
637 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
638 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
639 		if (mdata->rx_sgl) {
640 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
641 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
642 		}
643 	}
644 
645 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
646 		/* spi disable dma */
647 		cmd = readl(mdata->base + SPI_CMD_REG);
648 		cmd &= ~SPI_CMD_TX_DMA;
649 		cmd &= ~SPI_CMD_RX_DMA;
650 		writel(cmd, mdata->base + SPI_CMD_REG);
651 
652 		spi_finalize_current_transfer(master);
653 		return IRQ_HANDLED;
654 	}
655 
656 	mtk_spi_update_mdata_len(master);
657 	mtk_spi_setup_packet(master);
658 	mtk_spi_setup_dma_addr(master, trans);
659 	mtk_spi_enable_transfer(master);
660 
661 	return IRQ_HANDLED;
662 }
663 
664 static int mtk_spi_probe(struct platform_device *pdev)
665 {
666 	struct spi_master *master;
667 	struct mtk_spi *mdata;
668 	const struct of_device_id *of_id;
669 	int i, irq, ret, addr_bits;
670 
671 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
672 	if (!master) {
673 		dev_err(&pdev->dev, "failed to alloc spi master\n");
674 		return -ENOMEM;
675 	}
676 
677 	master->auto_runtime_pm = true;
678 	master->dev.of_node = pdev->dev.of_node;
679 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
680 
681 	master->set_cs = mtk_spi_set_cs;
682 	master->prepare_message = mtk_spi_prepare_message;
683 	master->transfer_one = mtk_spi_transfer_one;
684 	master->can_dma = mtk_spi_can_dma;
685 	master->setup = mtk_spi_setup;
686 	master->set_cs_timing = mtk_spi_set_hw_cs_timing;
687 
688 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
689 	if (!of_id) {
690 		dev_err(&pdev->dev, "failed to probe of_node\n");
691 		ret = -EINVAL;
692 		goto err_put_master;
693 	}
694 
695 	mdata = spi_master_get_devdata(master);
696 	mdata->dev_comp = of_id->data;
697 
698 	if (mdata->dev_comp->enhance_timing)
699 		master->mode_bits |= SPI_CS_HIGH;
700 
701 	if (mdata->dev_comp->must_tx)
702 		master->flags = SPI_MASTER_MUST_TX;
703 
704 	if (mdata->dev_comp->need_pad_sel) {
705 		mdata->pad_num = of_property_count_u32_elems(
706 			pdev->dev.of_node,
707 			"mediatek,pad-select");
708 		if (mdata->pad_num < 0) {
709 			dev_err(&pdev->dev,
710 				"No 'mediatek,pad-select' property\n");
711 			ret = -EINVAL;
712 			goto err_put_master;
713 		}
714 
715 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
716 						    sizeof(u32), GFP_KERNEL);
717 		if (!mdata->pad_sel) {
718 			ret = -ENOMEM;
719 			goto err_put_master;
720 		}
721 
722 		for (i = 0; i < mdata->pad_num; i++) {
723 			of_property_read_u32_index(pdev->dev.of_node,
724 						   "mediatek,pad-select",
725 						   i, &mdata->pad_sel[i]);
726 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
727 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
728 					i, mdata->pad_sel[i]);
729 				ret = -EINVAL;
730 				goto err_put_master;
731 			}
732 		}
733 	}
734 
735 	platform_set_drvdata(pdev, master);
736 	mdata->base = devm_platform_ioremap_resource(pdev, 0);
737 	if (IS_ERR(mdata->base)) {
738 		ret = PTR_ERR(mdata->base);
739 		goto err_put_master;
740 	}
741 
742 	irq = platform_get_irq(pdev, 0);
743 	if (irq < 0) {
744 		ret = irq;
745 		goto err_put_master;
746 	}
747 
748 	if (!pdev->dev.dma_mask)
749 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
750 
751 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
752 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
753 	if (ret) {
754 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
755 		goto err_put_master;
756 	}
757 
758 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
759 	if (IS_ERR(mdata->parent_clk)) {
760 		ret = PTR_ERR(mdata->parent_clk);
761 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
762 		goto err_put_master;
763 	}
764 
765 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
766 	if (IS_ERR(mdata->sel_clk)) {
767 		ret = PTR_ERR(mdata->sel_clk);
768 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
769 		goto err_put_master;
770 	}
771 
772 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
773 	if (IS_ERR(mdata->spi_clk)) {
774 		ret = PTR_ERR(mdata->spi_clk);
775 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
776 		goto err_put_master;
777 	}
778 
779 	ret = clk_prepare_enable(mdata->spi_clk);
780 	if (ret < 0) {
781 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
782 		goto err_put_master;
783 	}
784 
785 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
786 	if (ret < 0) {
787 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
788 		clk_disable_unprepare(mdata->spi_clk);
789 		goto err_put_master;
790 	}
791 
792 	clk_disable_unprepare(mdata->spi_clk);
793 
794 	pm_runtime_enable(&pdev->dev);
795 
796 	ret = devm_spi_register_master(&pdev->dev, master);
797 	if (ret) {
798 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
799 		goto err_disable_runtime_pm;
800 	}
801 
802 	if (mdata->dev_comp->need_pad_sel) {
803 		if (mdata->pad_num != master->num_chipselect) {
804 			dev_err(&pdev->dev,
805 				"pad_num does not match num_chipselect(%d != %d)\n",
806 				mdata->pad_num, master->num_chipselect);
807 			ret = -EINVAL;
808 			goto err_disable_runtime_pm;
809 		}
810 
811 		if (!master->cs_gpios && master->num_chipselect > 1) {
812 			dev_err(&pdev->dev,
813 				"cs_gpios not specified and num_chipselect > 1\n");
814 			ret = -EINVAL;
815 			goto err_disable_runtime_pm;
816 		}
817 
818 		if (master->cs_gpios) {
819 			for (i = 0; i < master->num_chipselect; i++) {
820 				ret = devm_gpio_request(&pdev->dev,
821 							master->cs_gpios[i],
822 							dev_name(&pdev->dev));
823 				if (ret) {
824 					dev_err(&pdev->dev,
825 						"can't get CS GPIO %i\n", i);
826 					goto err_disable_runtime_pm;
827 				}
828 			}
829 		}
830 	}
831 
832 	if (mdata->dev_comp->dma_ext)
833 		addr_bits = DMA_ADDR_EXT_BITS;
834 	else
835 		addr_bits = DMA_ADDR_DEF_BITS;
836 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
837 	if (ret)
838 		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
839 			   addr_bits, ret);
840 
841 	return 0;
842 
843 err_disable_runtime_pm:
844 	pm_runtime_disable(&pdev->dev);
845 err_put_master:
846 	spi_master_put(master);
847 
848 	return ret;
849 }
850 
851 static int mtk_spi_remove(struct platform_device *pdev)
852 {
853 	struct spi_master *master = platform_get_drvdata(pdev);
854 	struct mtk_spi *mdata = spi_master_get_devdata(master);
855 
856 	pm_runtime_disable(&pdev->dev);
857 
858 	mtk_spi_reset(mdata);
859 
860 	return 0;
861 }
862 
863 #ifdef CONFIG_PM_SLEEP
864 static int mtk_spi_suspend(struct device *dev)
865 {
866 	int ret;
867 	struct spi_master *master = dev_get_drvdata(dev);
868 	struct mtk_spi *mdata = spi_master_get_devdata(master);
869 
870 	ret = spi_master_suspend(master);
871 	if (ret)
872 		return ret;
873 
874 	if (!pm_runtime_suspended(dev))
875 		clk_disable_unprepare(mdata->spi_clk);
876 
877 	return ret;
878 }
879 
880 static int mtk_spi_resume(struct device *dev)
881 {
882 	int ret;
883 	struct spi_master *master = dev_get_drvdata(dev);
884 	struct mtk_spi *mdata = spi_master_get_devdata(master);
885 
886 	if (!pm_runtime_suspended(dev)) {
887 		ret = clk_prepare_enable(mdata->spi_clk);
888 		if (ret < 0) {
889 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
890 			return ret;
891 		}
892 	}
893 
894 	ret = spi_master_resume(master);
895 	if (ret < 0)
896 		clk_disable_unprepare(mdata->spi_clk);
897 
898 	return ret;
899 }
900 #endif /* CONFIG_PM_SLEEP */
901 
902 #ifdef CONFIG_PM
903 static int mtk_spi_runtime_suspend(struct device *dev)
904 {
905 	struct spi_master *master = dev_get_drvdata(dev);
906 	struct mtk_spi *mdata = spi_master_get_devdata(master);
907 
908 	clk_disable_unprepare(mdata->spi_clk);
909 
910 	return 0;
911 }
912 
913 static int mtk_spi_runtime_resume(struct device *dev)
914 {
915 	struct spi_master *master = dev_get_drvdata(dev);
916 	struct mtk_spi *mdata = spi_master_get_devdata(master);
917 	int ret;
918 
919 	ret = clk_prepare_enable(mdata->spi_clk);
920 	if (ret < 0) {
921 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
922 		return ret;
923 	}
924 
925 	return 0;
926 }
927 #endif /* CONFIG_PM */
928 
929 static const struct dev_pm_ops mtk_spi_pm = {
930 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
931 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
932 			   mtk_spi_runtime_resume, NULL)
933 };
934 
935 static struct platform_driver mtk_spi_driver = {
936 	.driver = {
937 		.name = "mtk-spi",
938 		.pm	= &mtk_spi_pm,
939 		.of_match_table = mtk_spi_of_match,
940 	},
941 	.probe = mtk_spi_probe,
942 	.remove = mtk_spi_remove,
943 };
944 
945 module_platform_driver(mtk_spi_driver);
946 
947 MODULE_DESCRIPTION("MTK SPI Controller driver");
948 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
949 MODULE_LICENSE("GPL v2");
950 MODULE_ALIAS("platform:mtk-spi");
951