xref: /openbmc/linux/drivers/spi/spi-mt65xx.c (revision 0661cb2a)
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 	if (xfer->tx_buf)
431 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
432 
433 	if (xfer->rx_buf)
434 		ioread32_rep(mdata->base + SPI_RX_DATA_REG, xfer->rx_buf, cnt);
435 
436 	remainder = xfer->len % 4;
437 	if (remainder > 0) {
438 		reg_val = 0;
439 		if (xfer->tx_buf) {
440 			memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
441 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
442 		}
443 		if (xfer->rx_buf) {
444 			reg_val = readl(mdata->base + SPI_RX_DATA_REG);
445 			memcpy(xfer->rx_buf + (cnt * 4), &reg_val, remainder);
446 		}
447 	}
448 
449 	mtk_spi_enable_transfer(master);
450 
451 	return 1;
452 }
453 
454 static int mtk_spi_dma_transfer(struct spi_master *master,
455 				struct spi_device *spi,
456 				struct spi_transfer *xfer)
457 {
458 	int cmd;
459 	struct mtk_spi *mdata = spi_master_get_devdata(master);
460 
461 	mdata->tx_sgl = NULL;
462 	mdata->rx_sgl = NULL;
463 	mdata->tx_sgl_len = 0;
464 	mdata->rx_sgl_len = 0;
465 	mdata->cur_transfer = xfer;
466 	mdata->num_xfered = 0;
467 
468 	mtk_spi_prepare_transfer(master, xfer);
469 
470 	cmd = readl(mdata->base + SPI_CMD_REG);
471 	if (xfer->tx_buf)
472 		cmd |= SPI_CMD_TX_DMA;
473 	if (xfer->rx_buf)
474 		cmd |= SPI_CMD_RX_DMA;
475 	writel(cmd, mdata->base + SPI_CMD_REG);
476 
477 	if (xfer->tx_buf)
478 		mdata->tx_sgl = xfer->tx_sg.sgl;
479 	if (xfer->rx_buf)
480 		mdata->rx_sgl = xfer->rx_sg.sgl;
481 
482 	if (mdata->tx_sgl) {
483 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
484 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
485 	}
486 	if (mdata->rx_sgl) {
487 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
488 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
489 	}
490 
491 	mtk_spi_update_mdata_len(master);
492 	mtk_spi_setup_packet(master);
493 	mtk_spi_setup_dma_addr(master, xfer);
494 	mtk_spi_enable_transfer(master);
495 
496 	return 1;
497 }
498 
499 static int mtk_spi_transfer_one(struct spi_master *master,
500 				struct spi_device *spi,
501 				struct spi_transfer *xfer)
502 {
503 	if (master->can_dma(master, spi, xfer))
504 		return mtk_spi_dma_transfer(master, spi, xfer);
505 	else
506 		return mtk_spi_fifo_transfer(master, spi, xfer);
507 }
508 
509 static bool mtk_spi_can_dma(struct spi_master *master,
510 			    struct spi_device *spi,
511 			    struct spi_transfer *xfer)
512 {
513 	/* Buffers for DMA transactions must be 4-byte aligned */
514 	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
515 		(unsigned long)xfer->tx_buf % 4 == 0 &&
516 		(unsigned long)xfer->rx_buf % 4 == 0);
517 }
518 
519 static int mtk_spi_set_hw_cs_timing(struct spi_device *spi,
520 				    struct spi_delay *setup,
521 				    struct spi_delay *hold,
522 				    struct spi_delay *inactive)
523 {
524 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
525 	u16 setup_dly, hold_dly, inactive_dly;
526 	u32 reg_val;
527 
528 	if ((setup && setup->unit != SPI_DELAY_UNIT_SCK) ||
529 	    (hold && hold->unit != SPI_DELAY_UNIT_SCK) ||
530 	    (inactive && inactive->unit != SPI_DELAY_UNIT_SCK)) {
531 		dev_err(&spi->dev,
532 			"Invalid delay unit, should be SPI_DELAY_UNIT_SCK\n");
533 		return -EINVAL;
534 	}
535 
536 	setup_dly = setup ? setup->value : 1;
537 	hold_dly = hold ? hold->value : 1;
538 	inactive_dly = inactive ? inactive->value : 1;
539 
540 	reg_val = readl(mdata->base + SPI_CFG0_REG);
541 	if (mdata->dev_comp->enhance_timing) {
542 		reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
543 		reg_val |= (((hold_dly - 1) & 0xffff)
544 			   << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
545 		reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
546 		reg_val |= (((setup_dly - 1) & 0xffff)
547 			   << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
548 	} else {
549 		reg_val &= ~(0xff << SPI_CFG0_CS_HOLD_OFFSET);
550 		reg_val |= (((hold_dly - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
551 		reg_val &= ~(0xff << SPI_CFG0_CS_SETUP_OFFSET);
552 		reg_val |= (((setup_dly - 1) & 0xff)
553 			    << SPI_CFG0_CS_SETUP_OFFSET);
554 	}
555 	writel(reg_val, mdata->base + SPI_CFG0_REG);
556 
557 	reg_val = readl(mdata->base + SPI_CFG1_REG);
558 	reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
559 	reg_val |= (((inactive_dly - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
560 	writel(reg_val, mdata->base + SPI_CFG1_REG);
561 
562 	return 0;
563 }
564 
565 static int mtk_spi_setup(struct spi_device *spi)
566 {
567 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
568 
569 	if (!spi->controller_data)
570 		spi->controller_data = (void *)&mtk_default_chip_info;
571 
572 	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
573 		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
574 
575 	return 0;
576 }
577 
578 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
579 {
580 	u32 cmd, reg_val, cnt, remainder, len;
581 	struct spi_master *master = dev_id;
582 	struct mtk_spi *mdata = spi_master_get_devdata(master);
583 	struct spi_transfer *trans = mdata->cur_transfer;
584 
585 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
586 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
587 		mdata->state = MTK_SPI_PAUSED;
588 	else
589 		mdata->state = MTK_SPI_IDLE;
590 
591 	if (!master->can_dma(master, master->cur_msg->spi, trans)) {
592 		if (trans->rx_buf) {
593 			cnt = mdata->xfer_len / 4;
594 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
595 				     trans->rx_buf + mdata->num_xfered, cnt);
596 			remainder = mdata->xfer_len % 4;
597 			if (remainder > 0) {
598 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
599 				memcpy(trans->rx_buf +
600 					mdata->num_xfered +
601 					(cnt * 4),
602 					&reg_val,
603 					remainder);
604 			}
605 		}
606 
607 		mdata->num_xfered += mdata->xfer_len;
608 		if (mdata->num_xfered == trans->len) {
609 			spi_finalize_current_transfer(master);
610 			return IRQ_HANDLED;
611 		}
612 
613 		len = trans->len - mdata->num_xfered;
614 		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
615 		mtk_spi_setup_packet(master);
616 
617 		cnt = mdata->xfer_len / 4;
618 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
619 				trans->tx_buf + mdata->num_xfered, cnt);
620 
621 		remainder = mdata->xfer_len % 4;
622 		if (remainder > 0) {
623 			reg_val = 0;
624 			memcpy(&reg_val,
625 				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
626 				remainder);
627 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
628 		}
629 
630 		mtk_spi_enable_transfer(master);
631 
632 		return IRQ_HANDLED;
633 	}
634 
635 	if (mdata->tx_sgl)
636 		trans->tx_dma += mdata->xfer_len;
637 	if (mdata->rx_sgl)
638 		trans->rx_dma += mdata->xfer_len;
639 
640 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
641 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
642 		if (mdata->tx_sgl) {
643 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
644 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
645 		}
646 	}
647 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
648 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
649 		if (mdata->rx_sgl) {
650 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
651 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
652 		}
653 	}
654 
655 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
656 		/* spi disable dma */
657 		cmd = readl(mdata->base + SPI_CMD_REG);
658 		cmd &= ~SPI_CMD_TX_DMA;
659 		cmd &= ~SPI_CMD_RX_DMA;
660 		writel(cmd, mdata->base + SPI_CMD_REG);
661 
662 		spi_finalize_current_transfer(master);
663 		return IRQ_HANDLED;
664 	}
665 
666 	mtk_spi_update_mdata_len(master);
667 	mtk_spi_setup_packet(master);
668 	mtk_spi_setup_dma_addr(master, trans);
669 	mtk_spi_enable_transfer(master);
670 
671 	return IRQ_HANDLED;
672 }
673 
674 static int mtk_spi_probe(struct platform_device *pdev)
675 {
676 	struct spi_master *master;
677 	struct mtk_spi *mdata;
678 	const struct of_device_id *of_id;
679 	int i, irq, ret, addr_bits;
680 
681 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
682 	if (!master) {
683 		dev_err(&pdev->dev, "failed to alloc spi master\n");
684 		return -ENOMEM;
685 	}
686 
687 	master->auto_runtime_pm = true;
688 	master->dev.of_node = pdev->dev.of_node;
689 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
690 
691 	master->set_cs = mtk_spi_set_cs;
692 	master->prepare_message = mtk_spi_prepare_message;
693 	master->transfer_one = mtk_spi_transfer_one;
694 	master->can_dma = mtk_spi_can_dma;
695 	master->setup = mtk_spi_setup;
696 	master->set_cs_timing = mtk_spi_set_hw_cs_timing;
697 
698 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
699 	if (!of_id) {
700 		dev_err(&pdev->dev, "failed to probe of_node\n");
701 		ret = -EINVAL;
702 		goto err_put_master;
703 	}
704 
705 	mdata = spi_master_get_devdata(master);
706 	mdata->dev_comp = of_id->data;
707 
708 	if (mdata->dev_comp->enhance_timing)
709 		master->mode_bits |= SPI_CS_HIGH;
710 
711 	if (mdata->dev_comp->must_tx)
712 		master->flags = SPI_MASTER_MUST_TX;
713 
714 	if (mdata->dev_comp->need_pad_sel) {
715 		mdata->pad_num = of_property_count_u32_elems(
716 			pdev->dev.of_node,
717 			"mediatek,pad-select");
718 		if (mdata->pad_num < 0) {
719 			dev_err(&pdev->dev,
720 				"No 'mediatek,pad-select' property\n");
721 			ret = -EINVAL;
722 			goto err_put_master;
723 		}
724 
725 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
726 						    sizeof(u32), GFP_KERNEL);
727 		if (!mdata->pad_sel) {
728 			ret = -ENOMEM;
729 			goto err_put_master;
730 		}
731 
732 		for (i = 0; i < mdata->pad_num; i++) {
733 			of_property_read_u32_index(pdev->dev.of_node,
734 						   "mediatek,pad-select",
735 						   i, &mdata->pad_sel[i]);
736 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
737 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
738 					i, mdata->pad_sel[i]);
739 				ret = -EINVAL;
740 				goto err_put_master;
741 			}
742 		}
743 	}
744 
745 	platform_set_drvdata(pdev, master);
746 	mdata->base = devm_platform_ioremap_resource(pdev, 0);
747 	if (IS_ERR(mdata->base)) {
748 		ret = PTR_ERR(mdata->base);
749 		goto err_put_master;
750 	}
751 
752 	irq = platform_get_irq(pdev, 0);
753 	if (irq < 0) {
754 		ret = irq;
755 		goto err_put_master;
756 	}
757 
758 	if (!pdev->dev.dma_mask)
759 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
760 
761 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
762 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
763 	if (ret) {
764 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
765 		goto err_put_master;
766 	}
767 
768 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
769 	if (IS_ERR(mdata->parent_clk)) {
770 		ret = PTR_ERR(mdata->parent_clk);
771 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
772 		goto err_put_master;
773 	}
774 
775 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
776 	if (IS_ERR(mdata->sel_clk)) {
777 		ret = PTR_ERR(mdata->sel_clk);
778 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
779 		goto err_put_master;
780 	}
781 
782 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
783 	if (IS_ERR(mdata->spi_clk)) {
784 		ret = PTR_ERR(mdata->spi_clk);
785 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
786 		goto err_put_master;
787 	}
788 
789 	ret = clk_prepare_enable(mdata->spi_clk);
790 	if (ret < 0) {
791 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
792 		goto err_put_master;
793 	}
794 
795 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
796 	if (ret < 0) {
797 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
798 		clk_disable_unprepare(mdata->spi_clk);
799 		goto err_put_master;
800 	}
801 
802 	clk_disable_unprepare(mdata->spi_clk);
803 
804 	pm_runtime_enable(&pdev->dev);
805 
806 	if (mdata->dev_comp->need_pad_sel) {
807 		if (mdata->pad_num != master->num_chipselect) {
808 			dev_err(&pdev->dev,
809 				"pad_num does not match num_chipselect(%d != %d)\n",
810 				mdata->pad_num, master->num_chipselect);
811 			ret = -EINVAL;
812 			goto err_disable_runtime_pm;
813 		}
814 
815 		if (!master->cs_gpios && master->num_chipselect > 1) {
816 			dev_err(&pdev->dev,
817 				"cs_gpios not specified and num_chipselect > 1\n");
818 			ret = -EINVAL;
819 			goto err_disable_runtime_pm;
820 		}
821 
822 		if (master->cs_gpios) {
823 			for (i = 0; i < master->num_chipselect; i++) {
824 				ret = devm_gpio_request(&pdev->dev,
825 							master->cs_gpios[i],
826 							dev_name(&pdev->dev));
827 				if (ret) {
828 					dev_err(&pdev->dev,
829 						"can't get CS GPIO %i\n", i);
830 					goto err_disable_runtime_pm;
831 				}
832 			}
833 		}
834 	}
835 
836 	if (mdata->dev_comp->dma_ext)
837 		addr_bits = DMA_ADDR_EXT_BITS;
838 	else
839 		addr_bits = DMA_ADDR_DEF_BITS;
840 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
841 	if (ret)
842 		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
843 			   addr_bits, ret);
844 
845 	ret = devm_spi_register_master(&pdev->dev, master);
846 	if (ret) {
847 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
848 		goto err_disable_runtime_pm;
849 	}
850 
851 	return 0;
852 
853 err_disable_runtime_pm:
854 	pm_runtime_disable(&pdev->dev);
855 err_put_master:
856 	spi_master_put(master);
857 
858 	return ret;
859 }
860 
861 static int mtk_spi_remove(struct platform_device *pdev)
862 {
863 	struct spi_master *master = platform_get_drvdata(pdev);
864 	struct mtk_spi *mdata = spi_master_get_devdata(master);
865 
866 	pm_runtime_disable(&pdev->dev);
867 
868 	mtk_spi_reset(mdata);
869 
870 	return 0;
871 }
872 
873 #ifdef CONFIG_PM_SLEEP
874 static int mtk_spi_suspend(struct device *dev)
875 {
876 	int ret;
877 	struct spi_master *master = dev_get_drvdata(dev);
878 	struct mtk_spi *mdata = spi_master_get_devdata(master);
879 
880 	ret = spi_master_suspend(master);
881 	if (ret)
882 		return ret;
883 
884 	if (!pm_runtime_suspended(dev))
885 		clk_disable_unprepare(mdata->spi_clk);
886 
887 	return ret;
888 }
889 
890 static int mtk_spi_resume(struct device *dev)
891 {
892 	int ret;
893 	struct spi_master *master = dev_get_drvdata(dev);
894 	struct mtk_spi *mdata = spi_master_get_devdata(master);
895 
896 	if (!pm_runtime_suspended(dev)) {
897 		ret = clk_prepare_enable(mdata->spi_clk);
898 		if (ret < 0) {
899 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
900 			return ret;
901 		}
902 	}
903 
904 	ret = spi_master_resume(master);
905 	if (ret < 0)
906 		clk_disable_unprepare(mdata->spi_clk);
907 
908 	return ret;
909 }
910 #endif /* CONFIG_PM_SLEEP */
911 
912 #ifdef CONFIG_PM
913 static int mtk_spi_runtime_suspend(struct device *dev)
914 {
915 	struct spi_master *master = dev_get_drvdata(dev);
916 	struct mtk_spi *mdata = spi_master_get_devdata(master);
917 
918 	clk_disable_unprepare(mdata->spi_clk);
919 
920 	return 0;
921 }
922 
923 static int mtk_spi_runtime_resume(struct device *dev)
924 {
925 	struct spi_master *master = dev_get_drvdata(dev);
926 	struct mtk_spi *mdata = spi_master_get_devdata(master);
927 	int ret;
928 
929 	ret = clk_prepare_enable(mdata->spi_clk);
930 	if (ret < 0) {
931 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
932 		return ret;
933 	}
934 
935 	return 0;
936 }
937 #endif /* CONFIG_PM */
938 
939 static const struct dev_pm_ops mtk_spi_pm = {
940 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
941 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
942 			   mtk_spi_runtime_resume, NULL)
943 };
944 
945 static struct platform_driver mtk_spi_driver = {
946 	.driver = {
947 		.name = "mtk-spi",
948 		.pm	= &mtk_spi_pm,
949 		.of_match_table = mtk_spi_of_match,
950 	},
951 	.probe = mtk_spi_probe,
952 	.remove = mtk_spi_remove,
953 };
954 
955 module_platform_driver(mtk_spi_driver);
956 
957 MODULE_DESCRIPTION("MTK SPI Controller driver");
958 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
959 MODULE_LICENSE("GPL v2");
960 MODULE_ALIAS("platform:mtk-spi");
961