xref: /openbmc/linux/drivers/spi/spi-mt65xx.c (revision c94b731d)
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      29
46 
47 #define SPI_CFG1_GET_TICK_DLY_MASK        0xe0000000
48 #define SPI_CFG1_CS_IDLE_MASK             0xff
49 #define SPI_CFG1_PACKET_LOOP_MASK         0xff00
50 #define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
51 #define SPI_CFG2_SCK_HIGH_OFFSET          0
52 #define SPI_CFG2_SCK_LOW_OFFSET           16
53 
54 #define SPI_CMD_ACT                  BIT(0)
55 #define SPI_CMD_RESUME               BIT(1)
56 #define SPI_CMD_RST                  BIT(2)
57 #define SPI_CMD_PAUSE_EN             BIT(4)
58 #define SPI_CMD_DEASSERT             BIT(5)
59 #define SPI_CMD_SAMPLE_SEL           BIT(6)
60 #define SPI_CMD_CS_POL               BIT(7)
61 #define SPI_CMD_CPHA                 BIT(8)
62 #define SPI_CMD_CPOL                 BIT(9)
63 #define SPI_CMD_RX_DMA               BIT(10)
64 #define SPI_CMD_TX_DMA               BIT(11)
65 #define SPI_CMD_TXMSBF               BIT(12)
66 #define SPI_CMD_RXMSBF               BIT(13)
67 #define SPI_CMD_RX_ENDIAN            BIT(14)
68 #define SPI_CMD_TX_ENDIAN            BIT(15)
69 #define SPI_CMD_FINISH_IE            BIT(16)
70 #define SPI_CMD_PAUSE_IE             BIT(17)
71 
72 #define MT8173_SPI_MAX_PAD_SEL 3
73 
74 #define MTK_SPI_PAUSE_INT_STATUS 0x2
75 
76 #define MTK_SPI_IDLE 0
77 #define MTK_SPI_PAUSED 1
78 
79 #define MTK_SPI_MAX_FIFO_SIZE 32U
80 #define MTK_SPI_PACKET_SIZE 1024
81 #define MTK_SPI_32BITS_MASK  (0xffffffff)
82 
83 #define DMA_ADDR_EXT_BITS (36)
84 #define DMA_ADDR_DEF_BITS (32)
85 
86 struct mtk_spi_compatible {
87 	bool need_pad_sel;
88 	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
89 	bool must_tx;
90 	/* some IC design adjust cfg register to enhance time accuracy */
91 	bool enhance_timing;
92 	/* some IC support DMA addr extension */
93 	bool dma_ext;
94 	/* some IC no need unprepare SPI clk */
95 	bool no_need_unprepare;
96 };
97 
98 struct mtk_spi {
99 	void __iomem *base;
100 	u32 state;
101 	int pad_num;
102 	u32 *pad_sel;
103 	struct clk *parent_clk, *sel_clk, *spi_clk;
104 	struct spi_transfer *cur_transfer;
105 	u32 xfer_len;
106 	u32 num_xfered;
107 	struct scatterlist *tx_sgl, *rx_sgl;
108 	u32 tx_sgl_len, rx_sgl_len;
109 	const struct mtk_spi_compatible *dev_comp;
110 	u32 spi_clk_hz;
111 };
112 
113 static const struct mtk_spi_compatible mtk_common_compat;
114 
115 static const struct mtk_spi_compatible mt2712_compat = {
116 	.must_tx = true,
117 };
118 
119 static const struct mtk_spi_compatible mt6765_compat = {
120 	.need_pad_sel = true,
121 	.must_tx = true,
122 	.enhance_timing = true,
123 	.dma_ext = true,
124 };
125 
126 static const struct mtk_spi_compatible mt7622_compat = {
127 	.must_tx = true,
128 	.enhance_timing = true,
129 };
130 
131 static const struct mtk_spi_compatible mt8173_compat = {
132 	.need_pad_sel = true,
133 	.must_tx = true,
134 };
135 
136 static const struct mtk_spi_compatible mt8183_compat = {
137 	.need_pad_sel = true,
138 	.must_tx = true,
139 	.enhance_timing = true,
140 };
141 
142 static const struct mtk_spi_compatible mt6893_compat = {
143 	.need_pad_sel = true,
144 	.must_tx = true,
145 	.enhance_timing = true,
146 	.dma_ext = true,
147 	.no_need_unprepare = true,
148 };
149 
150 /*
151  * A piece of default chip info unless the platform
152  * supplies it.
153  */
154 static const struct mtk_chip_config mtk_default_chip_info = {
155 	.sample_sel = 0,
156 	.tick_delay = 0,
157 };
158 
159 static const struct of_device_id mtk_spi_of_match[] = {
160 	{ .compatible = "mediatek,mt2701-spi",
161 		.data = (void *)&mtk_common_compat,
162 	},
163 	{ .compatible = "mediatek,mt2712-spi",
164 		.data = (void *)&mt2712_compat,
165 	},
166 	{ .compatible = "mediatek,mt6589-spi",
167 		.data = (void *)&mtk_common_compat,
168 	},
169 	{ .compatible = "mediatek,mt6765-spi",
170 		.data = (void *)&mt6765_compat,
171 	},
172 	{ .compatible = "mediatek,mt7622-spi",
173 		.data = (void *)&mt7622_compat,
174 	},
175 	{ .compatible = "mediatek,mt7629-spi",
176 		.data = (void *)&mt7622_compat,
177 	},
178 	{ .compatible = "mediatek,mt8135-spi",
179 		.data = (void *)&mtk_common_compat,
180 	},
181 	{ .compatible = "mediatek,mt8173-spi",
182 		.data = (void *)&mt8173_compat,
183 	},
184 	{ .compatible = "mediatek,mt8183-spi",
185 		.data = (void *)&mt8183_compat,
186 	},
187 	{ .compatible = "mediatek,mt8192-spi",
188 		.data = (void *)&mt6765_compat,
189 	},
190 	{ .compatible = "mediatek,mt6893-spi",
191 		.data = (void *)&mt6893_compat,
192 	},
193 	{}
194 };
195 MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
196 
197 static void mtk_spi_reset(struct mtk_spi *mdata)
198 {
199 	u32 reg_val;
200 
201 	/* set the software reset bit in SPI_CMD_REG. */
202 	reg_val = readl(mdata->base + SPI_CMD_REG);
203 	reg_val |= SPI_CMD_RST;
204 	writel(reg_val, mdata->base + SPI_CMD_REG);
205 
206 	reg_val = readl(mdata->base + SPI_CMD_REG);
207 	reg_val &= ~SPI_CMD_RST;
208 	writel(reg_val, mdata->base + SPI_CMD_REG);
209 }
210 
211 static int mtk_spi_set_hw_cs_timing(struct spi_device *spi)
212 {
213 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
214 	struct spi_delay *cs_setup = &spi->cs_setup;
215 	struct spi_delay *cs_hold = &spi->cs_hold;
216 	struct spi_delay *cs_inactive = &spi->cs_inactive;
217 	u32 setup, hold, inactive;
218 	u32 reg_val;
219 	int delay;
220 
221 	delay = spi_delay_to_ns(cs_setup, NULL);
222 	if (delay < 0)
223 		return delay;
224 	setup = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
225 
226 	delay = spi_delay_to_ns(cs_hold, NULL);
227 	if (delay < 0)
228 		return delay;
229 	hold = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
230 
231 	delay = spi_delay_to_ns(cs_inactive, NULL);
232 	if (delay < 0)
233 		return delay;
234 	inactive = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
235 
236 	if (hold || setup) {
237 		reg_val = readl(mdata->base + SPI_CFG0_REG);
238 		if (mdata->dev_comp->enhance_timing) {
239 			if (hold) {
240 				hold = min_t(u32, hold, 0x10000);
241 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
242 				reg_val |= (((hold - 1) & 0xffff)
243 					<< SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
244 			}
245 			if (setup) {
246 				setup = min_t(u32, setup, 0x10000);
247 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
248 				reg_val |= (((setup - 1) & 0xffff)
249 					<< SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
250 			}
251 		} else {
252 			if (hold) {
253 				hold = min_t(u32, hold, 0x100);
254 				reg_val &= ~(0xff << SPI_CFG0_CS_HOLD_OFFSET);
255 				reg_val |= (((hold - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
256 			}
257 			if (setup) {
258 				setup = min_t(u32, setup, 0x100);
259 				reg_val &= ~(0xff << SPI_CFG0_CS_SETUP_OFFSET);
260 				reg_val |= (((setup - 1) & 0xff)
261 					<< SPI_CFG0_CS_SETUP_OFFSET);
262 			}
263 		}
264 		writel(reg_val, mdata->base + SPI_CFG0_REG);
265 	}
266 
267 	if (inactive) {
268 		inactive = min_t(u32, inactive, 0x100);
269 		reg_val = readl(mdata->base + SPI_CFG1_REG);
270 		reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
271 		reg_val |= (((inactive - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
272 		writel(reg_val, mdata->base + SPI_CFG1_REG);
273 	}
274 
275 	return 0;
276 }
277 
278 static int mtk_spi_prepare_message(struct spi_master *master,
279 				   struct spi_message *msg)
280 {
281 	u16 cpha, cpol;
282 	u32 reg_val;
283 	struct spi_device *spi = msg->spi;
284 	struct mtk_chip_config *chip_config = spi->controller_data;
285 	struct mtk_spi *mdata = spi_master_get_devdata(master);
286 
287 	cpha = spi->mode & SPI_CPHA ? 1 : 0;
288 	cpol = spi->mode & SPI_CPOL ? 1 : 0;
289 
290 	reg_val = readl(mdata->base + SPI_CMD_REG);
291 	if (cpha)
292 		reg_val |= SPI_CMD_CPHA;
293 	else
294 		reg_val &= ~SPI_CMD_CPHA;
295 	if (cpol)
296 		reg_val |= SPI_CMD_CPOL;
297 	else
298 		reg_val &= ~SPI_CMD_CPOL;
299 
300 	/* set the mlsbx and mlsbtx */
301 	if (spi->mode & SPI_LSB_FIRST) {
302 		reg_val &= ~SPI_CMD_TXMSBF;
303 		reg_val &= ~SPI_CMD_RXMSBF;
304 	} else {
305 		reg_val |= SPI_CMD_TXMSBF;
306 		reg_val |= SPI_CMD_RXMSBF;
307 	}
308 
309 	/* set the tx/rx endian */
310 #ifdef __LITTLE_ENDIAN
311 	reg_val &= ~SPI_CMD_TX_ENDIAN;
312 	reg_val &= ~SPI_CMD_RX_ENDIAN;
313 #else
314 	reg_val |= SPI_CMD_TX_ENDIAN;
315 	reg_val |= SPI_CMD_RX_ENDIAN;
316 #endif
317 
318 	if (mdata->dev_comp->enhance_timing) {
319 		/* set CS polarity */
320 		if (spi->mode & SPI_CS_HIGH)
321 			reg_val |= SPI_CMD_CS_POL;
322 		else
323 			reg_val &= ~SPI_CMD_CS_POL;
324 
325 		if (chip_config->sample_sel)
326 			reg_val |= SPI_CMD_SAMPLE_SEL;
327 		else
328 			reg_val &= ~SPI_CMD_SAMPLE_SEL;
329 	}
330 
331 	/* set finish and pause interrupt always enable */
332 	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
333 
334 	/* disable dma mode */
335 	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
336 
337 	/* disable deassert mode */
338 	reg_val &= ~SPI_CMD_DEASSERT;
339 
340 	writel(reg_val, mdata->base + SPI_CMD_REG);
341 
342 	/* pad select */
343 	if (mdata->dev_comp->need_pad_sel)
344 		writel(mdata->pad_sel[spi->chip_select],
345 		       mdata->base + SPI_PAD_SEL_REG);
346 
347 	/* tick delay */
348 	reg_val = readl(mdata->base + SPI_CFG1_REG);
349 	reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK;
350 	reg_val |= ((chip_config->tick_delay & 0x7)
351 		<< SPI_CFG1_GET_TICK_DLY_OFFSET);
352 	writel(reg_val, mdata->base + SPI_CFG1_REG);
353 
354 	/* set hw cs timing */
355 	mtk_spi_set_hw_cs_timing(spi);
356 	return 0;
357 }
358 
359 static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
360 {
361 	u32 reg_val;
362 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
363 
364 	if (spi->mode & SPI_CS_HIGH)
365 		enable = !enable;
366 
367 	reg_val = readl(mdata->base + SPI_CMD_REG);
368 	if (!enable) {
369 		reg_val |= SPI_CMD_PAUSE_EN;
370 		writel(reg_val, mdata->base + SPI_CMD_REG);
371 	} else {
372 		reg_val &= ~SPI_CMD_PAUSE_EN;
373 		writel(reg_val, mdata->base + SPI_CMD_REG);
374 		mdata->state = MTK_SPI_IDLE;
375 		mtk_spi_reset(mdata);
376 	}
377 }
378 
379 static void mtk_spi_prepare_transfer(struct spi_master *master,
380 				     struct spi_transfer *xfer)
381 {
382 	u32 div, sck_time, reg_val;
383 	struct mtk_spi *mdata = spi_master_get_devdata(master);
384 
385 	if (xfer->speed_hz < mdata->spi_clk_hz / 2)
386 		div = DIV_ROUND_UP(mdata->spi_clk_hz, xfer->speed_hz);
387 	else
388 		div = 1;
389 
390 	sck_time = (div + 1) / 2;
391 
392 	if (mdata->dev_comp->enhance_timing) {
393 		reg_val = readl(mdata->base + SPI_CFG2_REG);
394 		reg_val &= ~(0xffff << SPI_CFG2_SCK_HIGH_OFFSET);
395 		reg_val |= (((sck_time - 1) & 0xffff)
396 			   << SPI_CFG2_SCK_HIGH_OFFSET);
397 		reg_val &= ~(0xffff << SPI_CFG2_SCK_LOW_OFFSET);
398 		reg_val |= (((sck_time - 1) & 0xffff)
399 			   << SPI_CFG2_SCK_LOW_OFFSET);
400 		writel(reg_val, mdata->base + SPI_CFG2_REG);
401 	} else {
402 		reg_val = readl(mdata->base + SPI_CFG0_REG);
403 		reg_val &= ~(0xff << SPI_CFG0_SCK_HIGH_OFFSET);
404 		reg_val |= (((sck_time - 1) & 0xff)
405 			   << SPI_CFG0_SCK_HIGH_OFFSET);
406 		reg_val &= ~(0xff << SPI_CFG0_SCK_LOW_OFFSET);
407 		reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
408 		writel(reg_val, mdata->base + SPI_CFG0_REG);
409 	}
410 }
411 
412 static void mtk_spi_setup_packet(struct spi_master *master)
413 {
414 	u32 packet_size, packet_loop, reg_val;
415 	struct mtk_spi *mdata = spi_master_get_devdata(master);
416 
417 	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
418 	packet_loop = mdata->xfer_len / packet_size;
419 
420 	reg_val = readl(mdata->base + SPI_CFG1_REG);
421 	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
422 	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
423 	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
424 	writel(reg_val, mdata->base + SPI_CFG1_REG);
425 }
426 
427 static void mtk_spi_enable_transfer(struct spi_master *master)
428 {
429 	u32 cmd;
430 	struct mtk_spi *mdata = spi_master_get_devdata(master);
431 
432 	cmd = readl(mdata->base + SPI_CMD_REG);
433 	if (mdata->state == MTK_SPI_IDLE)
434 		cmd |= SPI_CMD_ACT;
435 	else
436 		cmd |= SPI_CMD_RESUME;
437 	writel(cmd, mdata->base + SPI_CMD_REG);
438 }
439 
440 static int mtk_spi_get_mult_delta(u32 xfer_len)
441 {
442 	u32 mult_delta;
443 
444 	if (xfer_len > MTK_SPI_PACKET_SIZE)
445 		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
446 	else
447 		mult_delta = 0;
448 
449 	return mult_delta;
450 }
451 
452 static void mtk_spi_update_mdata_len(struct spi_master *master)
453 {
454 	int mult_delta;
455 	struct mtk_spi *mdata = spi_master_get_devdata(master);
456 
457 	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
458 		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
459 			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
460 			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
461 			mdata->rx_sgl_len = mult_delta;
462 			mdata->tx_sgl_len -= mdata->xfer_len;
463 		} else {
464 			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
465 			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
466 			mdata->tx_sgl_len = mult_delta;
467 			mdata->rx_sgl_len -= mdata->xfer_len;
468 		}
469 	} else if (mdata->tx_sgl_len) {
470 		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
471 		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
472 		mdata->tx_sgl_len = mult_delta;
473 	} else if (mdata->rx_sgl_len) {
474 		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
475 		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
476 		mdata->rx_sgl_len = mult_delta;
477 	}
478 }
479 
480 static void mtk_spi_setup_dma_addr(struct spi_master *master,
481 				   struct spi_transfer *xfer)
482 {
483 	struct mtk_spi *mdata = spi_master_get_devdata(master);
484 
485 	if (mdata->tx_sgl) {
486 		writel((u32)(xfer->tx_dma & MTK_SPI_32BITS_MASK),
487 		       mdata->base + SPI_TX_SRC_REG);
488 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
489 		if (mdata->dev_comp->dma_ext)
490 			writel((u32)(xfer->tx_dma >> 32),
491 			       mdata->base + SPI_TX_SRC_REG_64);
492 #endif
493 	}
494 
495 	if (mdata->rx_sgl) {
496 		writel((u32)(xfer->rx_dma & MTK_SPI_32BITS_MASK),
497 		       mdata->base + SPI_RX_DST_REG);
498 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
499 		if (mdata->dev_comp->dma_ext)
500 			writel((u32)(xfer->rx_dma >> 32),
501 			       mdata->base + SPI_RX_DST_REG_64);
502 #endif
503 	}
504 }
505 
506 static int mtk_spi_fifo_transfer(struct spi_master *master,
507 				 struct spi_device *spi,
508 				 struct spi_transfer *xfer)
509 {
510 	int cnt, remainder;
511 	u32 reg_val;
512 	struct mtk_spi *mdata = spi_master_get_devdata(master);
513 
514 	mdata->cur_transfer = xfer;
515 	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
516 	mdata->num_xfered = 0;
517 	mtk_spi_prepare_transfer(master, xfer);
518 	mtk_spi_setup_packet(master);
519 
520 	if (xfer->tx_buf) {
521 		cnt = xfer->len / 4;
522 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
523 		remainder = xfer->len % 4;
524 		if (remainder > 0) {
525 			reg_val = 0;
526 			memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
527 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
528 		}
529 	}
530 
531 	mtk_spi_enable_transfer(master);
532 
533 	return 1;
534 }
535 
536 static int mtk_spi_dma_transfer(struct spi_master *master,
537 				struct spi_device *spi,
538 				struct spi_transfer *xfer)
539 {
540 	int cmd;
541 	struct mtk_spi *mdata = spi_master_get_devdata(master);
542 
543 	mdata->tx_sgl = NULL;
544 	mdata->rx_sgl = NULL;
545 	mdata->tx_sgl_len = 0;
546 	mdata->rx_sgl_len = 0;
547 	mdata->cur_transfer = xfer;
548 	mdata->num_xfered = 0;
549 
550 	mtk_spi_prepare_transfer(master, xfer);
551 
552 	cmd = readl(mdata->base + SPI_CMD_REG);
553 	if (xfer->tx_buf)
554 		cmd |= SPI_CMD_TX_DMA;
555 	if (xfer->rx_buf)
556 		cmd |= SPI_CMD_RX_DMA;
557 	writel(cmd, mdata->base + SPI_CMD_REG);
558 
559 	if (xfer->tx_buf)
560 		mdata->tx_sgl = xfer->tx_sg.sgl;
561 	if (xfer->rx_buf)
562 		mdata->rx_sgl = xfer->rx_sg.sgl;
563 
564 	if (mdata->tx_sgl) {
565 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
566 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
567 	}
568 	if (mdata->rx_sgl) {
569 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
570 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
571 	}
572 
573 	mtk_spi_update_mdata_len(master);
574 	mtk_spi_setup_packet(master);
575 	mtk_spi_setup_dma_addr(master, xfer);
576 	mtk_spi_enable_transfer(master);
577 
578 	return 1;
579 }
580 
581 static int mtk_spi_transfer_one(struct spi_master *master,
582 				struct spi_device *spi,
583 				struct spi_transfer *xfer)
584 {
585 	if (master->can_dma(master, spi, xfer))
586 		return mtk_spi_dma_transfer(master, spi, xfer);
587 	else
588 		return mtk_spi_fifo_transfer(master, spi, xfer);
589 }
590 
591 static bool mtk_spi_can_dma(struct spi_master *master,
592 			    struct spi_device *spi,
593 			    struct spi_transfer *xfer)
594 {
595 	/* Buffers for DMA transactions must be 4-byte aligned */
596 	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
597 		(unsigned long)xfer->tx_buf % 4 == 0 &&
598 		(unsigned long)xfer->rx_buf % 4 == 0);
599 }
600 
601 static int mtk_spi_setup(struct spi_device *spi)
602 {
603 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
604 
605 	if (!spi->controller_data)
606 		spi->controller_data = (void *)&mtk_default_chip_info;
607 
608 	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
609 		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
610 
611 	return 0;
612 }
613 
614 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
615 {
616 	u32 cmd, reg_val, cnt, remainder, len;
617 	struct spi_master *master = dev_id;
618 	struct mtk_spi *mdata = spi_master_get_devdata(master);
619 	struct spi_transfer *trans = mdata->cur_transfer;
620 
621 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
622 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
623 		mdata->state = MTK_SPI_PAUSED;
624 	else
625 		mdata->state = MTK_SPI_IDLE;
626 
627 	if (!master->can_dma(master, NULL, trans)) {
628 		if (trans->rx_buf) {
629 			cnt = mdata->xfer_len / 4;
630 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
631 				     trans->rx_buf + mdata->num_xfered, cnt);
632 			remainder = mdata->xfer_len % 4;
633 			if (remainder > 0) {
634 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
635 				memcpy(trans->rx_buf +
636 					mdata->num_xfered +
637 					(cnt * 4),
638 					&reg_val,
639 					remainder);
640 			}
641 		}
642 
643 		mdata->num_xfered += mdata->xfer_len;
644 		if (mdata->num_xfered == trans->len) {
645 			spi_finalize_current_transfer(master);
646 			return IRQ_HANDLED;
647 		}
648 
649 		len = trans->len - mdata->num_xfered;
650 		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
651 		mtk_spi_setup_packet(master);
652 
653 		cnt = mdata->xfer_len / 4;
654 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
655 				trans->tx_buf + mdata->num_xfered, cnt);
656 
657 		remainder = mdata->xfer_len % 4;
658 		if (remainder > 0) {
659 			reg_val = 0;
660 			memcpy(&reg_val,
661 				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
662 				remainder);
663 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
664 		}
665 
666 		mtk_spi_enable_transfer(master);
667 
668 		return IRQ_HANDLED;
669 	}
670 
671 	if (mdata->tx_sgl)
672 		trans->tx_dma += mdata->xfer_len;
673 	if (mdata->rx_sgl)
674 		trans->rx_dma += mdata->xfer_len;
675 
676 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
677 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
678 		if (mdata->tx_sgl) {
679 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
680 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
681 		}
682 	}
683 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
684 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
685 		if (mdata->rx_sgl) {
686 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
687 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
688 		}
689 	}
690 
691 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
692 		/* spi disable dma */
693 		cmd = readl(mdata->base + SPI_CMD_REG);
694 		cmd &= ~SPI_CMD_TX_DMA;
695 		cmd &= ~SPI_CMD_RX_DMA;
696 		writel(cmd, mdata->base + SPI_CMD_REG);
697 
698 		spi_finalize_current_transfer(master);
699 		return IRQ_HANDLED;
700 	}
701 
702 	mtk_spi_update_mdata_len(master);
703 	mtk_spi_setup_packet(master);
704 	mtk_spi_setup_dma_addr(master, trans);
705 	mtk_spi_enable_transfer(master);
706 
707 	return IRQ_HANDLED;
708 }
709 
710 static int mtk_spi_probe(struct platform_device *pdev)
711 {
712 	struct spi_master *master;
713 	struct mtk_spi *mdata;
714 	const struct of_device_id *of_id;
715 	int i, irq, ret, addr_bits;
716 
717 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
718 	if (!master) {
719 		dev_err(&pdev->dev, "failed to alloc spi master\n");
720 		return -ENOMEM;
721 	}
722 
723 	master->auto_runtime_pm = true;
724 	master->dev.of_node = pdev->dev.of_node;
725 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
726 
727 	master->set_cs = mtk_spi_set_cs;
728 	master->prepare_message = mtk_spi_prepare_message;
729 	master->transfer_one = mtk_spi_transfer_one;
730 	master->can_dma = mtk_spi_can_dma;
731 	master->setup = mtk_spi_setup;
732 	master->set_cs_timing = mtk_spi_set_hw_cs_timing;
733 
734 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
735 	if (!of_id) {
736 		dev_err(&pdev->dev, "failed to probe of_node\n");
737 		ret = -EINVAL;
738 		goto err_put_master;
739 	}
740 
741 	mdata = spi_master_get_devdata(master);
742 	mdata->dev_comp = of_id->data;
743 
744 	if (mdata->dev_comp->enhance_timing)
745 		master->mode_bits |= SPI_CS_HIGH;
746 
747 	if (mdata->dev_comp->must_tx)
748 		master->flags = SPI_MASTER_MUST_TX;
749 
750 	if (mdata->dev_comp->need_pad_sel) {
751 		mdata->pad_num = of_property_count_u32_elems(
752 			pdev->dev.of_node,
753 			"mediatek,pad-select");
754 		if (mdata->pad_num < 0) {
755 			dev_err(&pdev->dev,
756 				"No 'mediatek,pad-select' property\n");
757 			ret = -EINVAL;
758 			goto err_put_master;
759 		}
760 
761 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
762 						    sizeof(u32), GFP_KERNEL);
763 		if (!mdata->pad_sel) {
764 			ret = -ENOMEM;
765 			goto err_put_master;
766 		}
767 
768 		for (i = 0; i < mdata->pad_num; i++) {
769 			of_property_read_u32_index(pdev->dev.of_node,
770 						   "mediatek,pad-select",
771 						   i, &mdata->pad_sel[i]);
772 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
773 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
774 					i, mdata->pad_sel[i]);
775 				ret = -EINVAL;
776 				goto err_put_master;
777 			}
778 		}
779 	}
780 
781 	platform_set_drvdata(pdev, master);
782 	mdata->base = devm_platform_ioremap_resource(pdev, 0);
783 	if (IS_ERR(mdata->base)) {
784 		ret = PTR_ERR(mdata->base);
785 		goto err_put_master;
786 	}
787 
788 	irq = platform_get_irq(pdev, 0);
789 	if (irq < 0) {
790 		ret = irq;
791 		goto err_put_master;
792 	}
793 
794 	if (!pdev->dev.dma_mask)
795 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
796 
797 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
798 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
799 	if (ret) {
800 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
801 		goto err_put_master;
802 	}
803 
804 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
805 	if (IS_ERR(mdata->parent_clk)) {
806 		ret = PTR_ERR(mdata->parent_clk);
807 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
808 		goto err_put_master;
809 	}
810 
811 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
812 	if (IS_ERR(mdata->sel_clk)) {
813 		ret = PTR_ERR(mdata->sel_clk);
814 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
815 		goto err_put_master;
816 	}
817 
818 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
819 	if (IS_ERR(mdata->spi_clk)) {
820 		ret = PTR_ERR(mdata->spi_clk);
821 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
822 		goto err_put_master;
823 	}
824 
825 	ret = clk_prepare_enable(mdata->spi_clk);
826 	if (ret < 0) {
827 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
828 		goto err_put_master;
829 	}
830 
831 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
832 	if (ret < 0) {
833 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
834 		clk_disable_unprepare(mdata->spi_clk);
835 		goto err_put_master;
836 	}
837 
838 	mdata->spi_clk_hz = clk_get_rate(mdata->spi_clk);
839 
840 	if (mdata->dev_comp->no_need_unprepare)
841 		clk_disable(mdata->spi_clk);
842 	else
843 		clk_disable_unprepare(mdata->spi_clk);
844 
845 	pm_runtime_enable(&pdev->dev);
846 
847 	if (mdata->dev_comp->need_pad_sel) {
848 		if (mdata->pad_num != master->num_chipselect) {
849 			dev_err(&pdev->dev,
850 				"pad_num does not match num_chipselect(%d != %d)\n",
851 				mdata->pad_num, master->num_chipselect);
852 			ret = -EINVAL;
853 			goto err_disable_runtime_pm;
854 		}
855 
856 		if (!master->cs_gpios && master->num_chipselect > 1) {
857 			dev_err(&pdev->dev,
858 				"cs_gpios not specified and num_chipselect > 1\n");
859 			ret = -EINVAL;
860 			goto err_disable_runtime_pm;
861 		}
862 
863 		if (master->cs_gpios) {
864 			for (i = 0; i < master->num_chipselect; i++) {
865 				ret = devm_gpio_request(&pdev->dev,
866 							master->cs_gpios[i],
867 							dev_name(&pdev->dev));
868 				if (ret) {
869 					dev_err(&pdev->dev,
870 						"can't get CS GPIO %i\n", i);
871 					goto err_disable_runtime_pm;
872 				}
873 			}
874 		}
875 	}
876 
877 	if (mdata->dev_comp->dma_ext)
878 		addr_bits = DMA_ADDR_EXT_BITS;
879 	else
880 		addr_bits = DMA_ADDR_DEF_BITS;
881 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
882 	if (ret)
883 		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
884 			   addr_bits, ret);
885 
886 	ret = devm_spi_register_master(&pdev->dev, master);
887 	if (ret) {
888 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
889 		goto err_disable_runtime_pm;
890 	}
891 
892 	return 0;
893 
894 err_disable_runtime_pm:
895 	pm_runtime_disable(&pdev->dev);
896 err_put_master:
897 	spi_master_put(master);
898 
899 	return ret;
900 }
901 
902 static int mtk_spi_remove(struct platform_device *pdev)
903 {
904 	struct spi_master *master = platform_get_drvdata(pdev);
905 	struct mtk_spi *mdata = spi_master_get_devdata(master);
906 
907 	pm_runtime_disable(&pdev->dev);
908 
909 	mtk_spi_reset(mdata);
910 
911 	if (mdata->dev_comp->no_need_unprepare)
912 		clk_unprepare(mdata->spi_clk);
913 
914 	return 0;
915 }
916 
917 #ifdef CONFIG_PM_SLEEP
918 static int mtk_spi_suspend(struct device *dev)
919 {
920 	int ret;
921 	struct spi_master *master = dev_get_drvdata(dev);
922 	struct mtk_spi *mdata = spi_master_get_devdata(master);
923 
924 	ret = spi_master_suspend(master);
925 	if (ret)
926 		return ret;
927 
928 	if (!pm_runtime_suspended(dev))
929 		clk_disable_unprepare(mdata->spi_clk);
930 
931 	return ret;
932 }
933 
934 static int mtk_spi_resume(struct device *dev)
935 {
936 	int ret;
937 	struct spi_master *master = dev_get_drvdata(dev);
938 	struct mtk_spi *mdata = spi_master_get_devdata(master);
939 
940 	if (!pm_runtime_suspended(dev)) {
941 		ret = clk_prepare_enable(mdata->spi_clk);
942 		if (ret < 0) {
943 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
944 			return ret;
945 		}
946 	}
947 
948 	ret = spi_master_resume(master);
949 	if (ret < 0)
950 		clk_disable_unprepare(mdata->spi_clk);
951 
952 	return ret;
953 }
954 #endif /* CONFIG_PM_SLEEP */
955 
956 #ifdef CONFIG_PM
957 static int mtk_spi_runtime_suspend(struct device *dev)
958 {
959 	struct spi_master *master = dev_get_drvdata(dev);
960 	struct mtk_spi *mdata = spi_master_get_devdata(master);
961 
962 	if (mdata->dev_comp->no_need_unprepare)
963 		clk_disable(mdata->spi_clk);
964 	else
965 		clk_disable_unprepare(mdata->spi_clk);
966 
967 	return 0;
968 }
969 
970 static int mtk_spi_runtime_resume(struct device *dev)
971 {
972 	struct spi_master *master = dev_get_drvdata(dev);
973 	struct mtk_spi *mdata = spi_master_get_devdata(master);
974 	int ret;
975 
976 	if (mdata->dev_comp->no_need_unprepare)
977 		ret = clk_enable(mdata->spi_clk);
978 	else
979 		ret = clk_prepare_enable(mdata->spi_clk);
980 	if (ret < 0) {
981 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
982 		return ret;
983 	}
984 
985 	return 0;
986 }
987 #endif /* CONFIG_PM */
988 
989 static const struct dev_pm_ops mtk_spi_pm = {
990 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
991 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
992 			   mtk_spi_runtime_resume, NULL)
993 };
994 
995 static struct platform_driver mtk_spi_driver = {
996 	.driver = {
997 		.name = "mtk-spi",
998 		.pm	= &mtk_spi_pm,
999 		.of_match_table = mtk_spi_of_match,
1000 	},
1001 	.probe = mtk_spi_probe,
1002 	.remove = mtk_spi_remove,
1003 };
1004 
1005 module_platform_driver(mtk_spi_driver);
1006 
1007 MODULE_DESCRIPTION("MTK SPI Controller driver");
1008 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
1009 MODULE_LICENSE("GPL v2");
1010 MODULE_ALIAS("platform:mtk-spi");
1011