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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 #define SPI_CFG1_GET_TICK_DLY_OFFSET_V1   30
47 
48 #define SPI_CFG1_GET_TICK_DLY_MASK        0xe0000000
49 #define SPI_CFG1_GET_TICK_DLY_MASK_V1     0xc0000000
50 
51 #define SPI_CFG1_CS_IDLE_MASK             0xff
52 #define SPI_CFG1_PACKET_LOOP_MASK         0xff00
53 #define SPI_CFG1_PACKET_LENGTH_MASK       0x3ff0000
54 #define SPI_CFG2_SCK_HIGH_OFFSET          0
55 #define SPI_CFG2_SCK_LOW_OFFSET           16
56 
57 #define SPI_CMD_ACT                  BIT(0)
58 #define SPI_CMD_RESUME               BIT(1)
59 #define SPI_CMD_RST                  BIT(2)
60 #define SPI_CMD_PAUSE_EN             BIT(4)
61 #define SPI_CMD_DEASSERT             BIT(5)
62 #define SPI_CMD_SAMPLE_SEL           BIT(6)
63 #define SPI_CMD_CS_POL               BIT(7)
64 #define SPI_CMD_CPHA                 BIT(8)
65 #define SPI_CMD_CPOL                 BIT(9)
66 #define SPI_CMD_RX_DMA               BIT(10)
67 #define SPI_CMD_TX_DMA               BIT(11)
68 #define SPI_CMD_TXMSBF               BIT(12)
69 #define SPI_CMD_RXMSBF               BIT(13)
70 #define SPI_CMD_RX_ENDIAN            BIT(14)
71 #define SPI_CMD_TX_ENDIAN            BIT(15)
72 #define SPI_CMD_FINISH_IE            BIT(16)
73 #define SPI_CMD_PAUSE_IE             BIT(17)
74 
75 #define MT8173_SPI_MAX_PAD_SEL 3
76 
77 #define MTK_SPI_PAUSE_INT_STATUS 0x2
78 
79 #define MTK_SPI_IDLE 0
80 #define MTK_SPI_PAUSED 1
81 
82 #define MTK_SPI_MAX_FIFO_SIZE 32U
83 #define MTK_SPI_PACKET_SIZE 1024
84 #define MTK_SPI_32BITS_MASK  (0xffffffff)
85 
86 #define DMA_ADDR_EXT_BITS (36)
87 #define DMA_ADDR_DEF_BITS (32)
88 
89 struct mtk_spi_compatible {
90 	bool need_pad_sel;
91 	/* Must explicitly send dummy Tx bytes to do Rx only transfer */
92 	bool must_tx;
93 	/* some IC design adjust cfg register to enhance time accuracy */
94 	bool enhance_timing;
95 	/* some IC support DMA addr extension */
96 	bool dma_ext;
97 	/* some IC no need unprepare SPI clk */
98 	bool no_need_unprepare;
99 };
100 
101 struct mtk_spi {
102 	void __iomem *base;
103 	u32 state;
104 	int pad_num;
105 	u32 *pad_sel;
106 	struct clk *parent_clk, *sel_clk, *spi_clk;
107 	struct spi_transfer *cur_transfer;
108 	u32 xfer_len;
109 	u32 num_xfered;
110 	struct scatterlist *tx_sgl, *rx_sgl;
111 	u32 tx_sgl_len, rx_sgl_len;
112 	const struct mtk_spi_compatible *dev_comp;
113 	u32 spi_clk_hz;
114 };
115 
116 static const struct mtk_spi_compatible mtk_common_compat;
117 
118 static const struct mtk_spi_compatible mt2712_compat = {
119 	.must_tx = true,
120 };
121 
122 static const struct mtk_spi_compatible mt6765_compat = {
123 	.need_pad_sel = true,
124 	.must_tx = true,
125 	.enhance_timing = true,
126 	.dma_ext = true,
127 };
128 
129 static const struct mtk_spi_compatible mt7622_compat = {
130 	.must_tx = true,
131 	.enhance_timing = true,
132 };
133 
134 static const struct mtk_spi_compatible mt8173_compat = {
135 	.need_pad_sel = true,
136 	.must_tx = true,
137 };
138 
139 static const struct mtk_spi_compatible mt8183_compat = {
140 	.need_pad_sel = true,
141 	.must_tx = true,
142 	.enhance_timing = true,
143 };
144 
145 static const struct mtk_spi_compatible mt6893_compat = {
146 	.need_pad_sel = true,
147 	.must_tx = true,
148 	.enhance_timing = true,
149 	.dma_ext = true,
150 	.no_need_unprepare = true,
151 };
152 
153 /*
154  * A piece of default chip info unless the platform
155  * supplies it.
156  */
157 static const struct mtk_chip_config mtk_default_chip_info = {
158 	.sample_sel = 0,
159 	.tick_delay = 0,
160 };
161 
162 static const struct of_device_id mtk_spi_of_match[] = {
163 	{ .compatible = "mediatek,mt2701-spi",
164 		.data = (void *)&mtk_common_compat,
165 	},
166 	{ .compatible = "mediatek,mt2712-spi",
167 		.data = (void *)&mt2712_compat,
168 	},
169 	{ .compatible = "mediatek,mt6589-spi",
170 		.data = (void *)&mtk_common_compat,
171 	},
172 	{ .compatible = "mediatek,mt6765-spi",
173 		.data = (void *)&mt6765_compat,
174 	},
175 	{ .compatible = "mediatek,mt7622-spi",
176 		.data = (void *)&mt7622_compat,
177 	},
178 	{ .compatible = "mediatek,mt7629-spi",
179 		.data = (void *)&mt7622_compat,
180 	},
181 	{ .compatible = "mediatek,mt8135-spi",
182 		.data = (void *)&mtk_common_compat,
183 	},
184 	{ .compatible = "mediatek,mt8173-spi",
185 		.data = (void *)&mt8173_compat,
186 	},
187 	{ .compatible = "mediatek,mt8183-spi",
188 		.data = (void *)&mt8183_compat,
189 	},
190 	{ .compatible = "mediatek,mt8192-spi",
191 		.data = (void *)&mt6765_compat,
192 	},
193 	{ .compatible = "mediatek,mt6893-spi",
194 		.data = (void *)&mt6893_compat,
195 	},
196 	{}
197 };
198 MODULE_DEVICE_TABLE(of, mtk_spi_of_match);
199 
mtk_spi_reset(struct mtk_spi * mdata)200 static void mtk_spi_reset(struct mtk_spi *mdata)
201 {
202 	u32 reg_val;
203 
204 	/* set the software reset bit in SPI_CMD_REG. */
205 	reg_val = readl(mdata->base + SPI_CMD_REG);
206 	reg_val |= SPI_CMD_RST;
207 	writel(reg_val, mdata->base + SPI_CMD_REG);
208 
209 	reg_val = readl(mdata->base + SPI_CMD_REG);
210 	reg_val &= ~SPI_CMD_RST;
211 	writel(reg_val, mdata->base + SPI_CMD_REG);
212 }
213 
mtk_spi_set_hw_cs_timing(struct spi_device * spi)214 static int mtk_spi_set_hw_cs_timing(struct spi_device *spi)
215 {
216 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
217 	struct spi_delay *cs_setup = &spi->cs_setup;
218 	struct spi_delay *cs_hold = &spi->cs_hold;
219 	struct spi_delay *cs_inactive = &spi->cs_inactive;
220 	u32 setup, hold, inactive;
221 	u32 reg_val;
222 	int delay;
223 
224 	delay = spi_delay_to_ns(cs_setup, NULL);
225 	if (delay < 0)
226 		return delay;
227 	setup = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
228 
229 	delay = spi_delay_to_ns(cs_hold, NULL);
230 	if (delay < 0)
231 		return delay;
232 	hold = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
233 
234 	delay = spi_delay_to_ns(cs_inactive, NULL);
235 	if (delay < 0)
236 		return delay;
237 	inactive = (delay * DIV_ROUND_UP(mdata->spi_clk_hz, 1000000)) / 1000;
238 
239 	if (hold || setup) {
240 		reg_val = readl(mdata->base + SPI_CFG0_REG);
241 		if (mdata->dev_comp->enhance_timing) {
242 			if (hold) {
243 				hold = min_t(u32, hold, 0x10000);
244 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
245 				reg_val |= (((hold - 1) & 0xffff)
246 					<< SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
247 			}
248 			if (setup) {
249 				setup = min_t(u32, setup, 0x10000);
250 				reg_val &= ~(0xffff << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
251 				reg_val |= (((setup - 1) & 0xffff)
252 					<< SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
253 			}
254 		} else {
255 			if (hold) {
256 				hold = min_t(u32, hold, 0x100);
257 				reg_val &= ~(0xff << SPI_CFG0_CS_HOLD_OFFSET);
258 				reg_val |= (((hold - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
259 			}
260 			if (setup) {
261 				setup = min_t(u32, setup, 0x100);
262 				reg_val &= ~(0xff << SPI_CFG0_CS_SETUP_OFFSET);
263 				reg_val |= (((setup - 1) & 0xff)
264 					<< SPI_CFG0_CS_SETUP_OFFSET);
265 			}
266 		}
267 		writel(reg_val, mdata->base + SPI_CFG0_REG);
268 	}
269 
270 	if (inactive) {
271 		inactive = min_t(u32, inactive, 0x100);
272 		reg_val = readl(mdata->base + SPI_CFG1_REG);
273 		reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
274 		reg_val |= (((inactive - 1) & 0xff) << SPI_CFG1_CS_IDLE_OFFSET);
275 		writel(reg_val, mdata->base + SPI_CFG1_REG);
276 	}
277 
278 	return 0;
279 }
280 
mtk_spi_prepare_message(struct spi_master * master,struct spi_message * msg)281 static int mtk_spi_prepare_message(struct spi_master *master,
282 				   struct spi_message *msg)
283 {
284 	u16 cpha, cpol;
285 	u32 reg_val;
286 	struct spi_device *spi = msg->spi;
287 	struct mtk_chip_config *chip_config = spi->controller_data;
288 	struct mtk_spi *mdata = spi_master_get_devdata(master);
289 
290 	cpha = spi->mode & SPI_CPHA ? 1 : 0;
291 	cpol = spi->mode & SPI_CPOL ? 1 : 0;
292 
293 	reg_val = readl(mdata->base + SPI_CMD_REG);
294 	if (cpha)
295 		reg_val |= SPI_CMD_CPHA;
296 	else
297 		reg_val &= ~SPI_CMD_CPHA;
298 	if (cpol)
299 		reg_val |= SPI_CMD_CPOL;
300 	else
301 		reg_val &= ~SPI_CMD_CPOL;
302 
303 	/* set the mlsbx and mlsbtx */
304 	if (spi->mode & SPI_LSB_FIRST) {
305 		reg_val &= ~SPI_CMD_TXMSBF;
306 		reg_val &= ~SPI_CMD_RXMSBF;
307 	} else {
308 		reg_val |= SPI_CMD_TXMSBF;
309 		reg_val |= SPI_CMD_RXMSBF;
310 	}
311 
312 	/* set the tx/rx endian */
313 #ifdef __LITTLE_ENDIAN
314 	reg_val &= ~SPI_CMD_TX_ENDIAN;
315 	reg_val &= ~SPI_CMD_RX_ENDIAN;
316 #else
317 	reg_val |= SPI_CMD_TX_ENDIAN;
318 	reg_val |= SPI_CMD_RX_ENDIAN;
319 #endif
320 
321 	if (mdata->dev_comp->enhance_timing) {
322 		/* set CS polarity */
323 		if (spi->mode & SPI_CS_HIGH)
324 			reg_val |= SPI_CMD_CS_POL;
325 		else
326 			reg_val &= ~SPI_CMD_CS_POL;
327 
328 		if (chip_config->sample_sel)
329 			reg_val |= SPI_CMD_SAMPLE_SEL;
330 		else
331 			reg_val &= ~SPI_CMD_SAMPLE_SEL;
332 	}
333 
334 	/* set finish and pause interrupt always enable */
335 	reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
336 
337 	/* disable dma mode */
338 	reg_val &= ~(SPI_CMD_TX_DMA | SPI_CMD_RX_DMA);
339 
340 	/* disable deassert mode */
341 	reg_val &= ~SPI_CMD_DEASSERT;
342 
343 	writel(reg_val, mdata->base + SPI_CMD_REG);
344 
345 	/* pad select */
346 	if (mdata->dev_comp->need_pad_sel)
347 		writel(mdata->pad_sel[spi->chip_select],
348 		       mdata->base + SPI_PAD_SEL_REG);
349 
350 	/* tick delay */
351 	reg_val = readl(mdata->base + SPI_CFG1_REG);
352 	if (mdata->dev_comp->enhance_timing) {
353 		reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK;
354 		reg_val |= ((chip_config->tick_delay & 0x7)
355 			    << SPI_CFG1_GET_TICK_DLY_OFFSET);
356 	} else {
357 		reg_val &= ~SPI_CFG1_GET_TICK_DLY_MASK_V1;
358 		reg_val |= ((chip_config->tick_delay & 0x3)
359 			    << SPI_CFG1_GET_TICK_DLY_OFFSET_V1);
360 	}
361 	writel(reg_val, mdata->base + SPI_CFG1_REG);
362 
363 	/* set hw cs timing */
364 	mtk_spi_set_hw_cs_timing(spi);
365 	return 0;
366 }
367 
mtk_spi_set_cs(struct spi_device * spi,bool enable)368 static void mtk_spi_set_cs(struct spi_device *spi, bool enable)
369 {
370 	u32 reg_val;
371 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
372 
373 	if (spi->mode & SPI_CS_HIGH)
374 		enable = !enable;
375 
376 	reg_val = readl(mdata->base + SPI_CMD_REG);
377 	if (!enable) {
378 		reg_val |= SPI_CMD_PAUSE_EN;
379 		writel(reg_val, mdata->base + SPI_CMD_REG);
380 	} else {
381 		reg_val &= ~SPI_CMD_PAUSE_EN;
382 		writel(reg_val, mdata->base + SPI_CMD_REG);
383 		mdata->state = MTK_SPI_IDLE;
384 		mtk_spi_reset(mdata);
385 	}
386 }
387 
mtk_spi_prepare_transfer(struct spi_master * master,struct spi_transfer * xfer)388 static void mtk_spi_prepare_transfer(struct spi_master *master,
389 				     struct spi_transfer *xfer)
390 {
391 	u32 div, sck_time, reg_val;
392 	struct mtk_spi *mdata = spi_master_get_devdata(master);
393 
394 	if (xfer->speed_hz < mdata->spi_clk_hz / 2)
395 		div = DIV_ROUND_UP(mdata->spi_clk_hz, xfer->speed_hz);
396 	else
397 		div = 1;
398 
399 	sck_time = (div + 1) / 2;
400 
401 	if (mdata->dev_comp->enhance_timing) {
402 		reg_val = readl(mdata->base + SPI_CFG2_REG);
403 		reg_val &= ~(0xffff << SPI_CFG2_SCK_HIGH_OFFSET);
404 		reg_val |= (((sck_time - 1) & 0xffff)
405 			   << SPI_CFG2_SCK_HIGH_OFFSET);
406 		reg_val &= ~(0xffff << SPI_CFG2_SCK_LOW_OFFSET);
407 		reg_val |= (((sck_time - 1) & 0xffff)
408 			   << SPI_CFG2_SCK_LOW_OFFSET);
409 		writel(reg_val, mdata->base + SPI_CFG2_REG);
410 	} else {
411 		reg_val = readl(mdata->base + SPI_CFG0_REG);
412 		reg_val &= ~(0xff << SPI_CFG0_SCK_HIGH_OFFSET);
413 		reg_val |= (((sck_time - 1) & 0xff)
414 			   << SPI_CFG0_SCK_HIGH_OFFSET);
415 		reg_val &= ~(0xff << SPI_CFG0_SCK_LOW_OFFSET);
416 		reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
417 		writel(reg_val, mdata->base + SPI_CFG0_REG);
418 	}
419 }
420 
mtk_spi_setup_packet(struct spi_master * master)421 static void mtk_spi_setup_packet(struct spi_master *master)
422 {
423 	u32 packet_size, packet_loop, reg_val;
424 	struct mtk_spi *mdata = spi_master_get_devdata(master);
425 
426 	packet_size = min_t(u32, mdata->xfer_len, MTK_SPI_PACKET_SIZE);
427 	packet_loop = mdata->xfer_len / packet_size;
428 
429 	reg_val = readl(mdata->base + SPI_CFG1_REG);
430 	reg_val &= ~(SPI_CFG1_PACKET_LENGTH_MASK | SPI_CFG1_PACKET_LOOP_MASK);
431 	reg_val |= (packet_size - 1) << SPI_CFG1_PACKET_LENGTH_OFFSET;
432 	reg_val |= (packet_loop - 1) << SPI_CFG1_PACKET_LOOP_OFFSET;
433 	writel(reg_val, mdata->base + SPI_CFG1_REG);
434 }
435 
mtk_spi_enable_transfer(struct spi_master * master)436 static void mtk_spi_enable_transfer(struct spi_master *master)
437 {
438 	u32 cmd;
439 	struct mtk_spi *mdata = spi_master_get_devdata(master);
440 
441 	cmd = readl(mdata->base + SPI_CMD_REG);
442 	if (mdata->state == MTK_SPI_IDLE)
443 		cmd |= SPI_CMD_ACT;
444 	else
445 		cmd |= SPI_CMD_RESUME;
446 	writel(cmd, mdata->base + SPI_CMD_REG);
447 }
448 
mtk_spi_get_mult_delta(u32 xfer_len)449 static int mtk_spi_get_mult_delta(u32 xfer_len)
450 {
451 	u32 mult_delta;
452 
453 	if (xfer_len > MTK_SPI_PACKET_SIZE)
454 		mult_delta = xfer_len % MTK_SPI_PACKET_SIZE;
455 	else
456 		mult_delta = 0;
457 
458 	return mult_delta;
459 }
460 
mtk_spi_update_mdata_len(struct spi_master * master)461 static void mtk_spi_update_mdata_len(struct spi_master *master)
462 {
463 	int mult_delta;
464 	struct mtk_spi *mdata = spi_master_get_devdata(master);
465 
466 	if (mdata->tx_sgl_len && mdata->rx_sgl_len) {
467 		if (mdata->tx_sgl_len > mdata->rx_sgl_len) {
468 			mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
469 			mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
470 			mdata->rx_sgl_len = mult_delta;
471 			mdata->tx_sgl_len -= mdata->xfer_len;
472 		} else {
473 			mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
474 			mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
475 			mdata->tx_sgl_len = mult_delta;
476 			mdata->rx_sgl_len -= mdata->xfer_len;
477 		}
478 	} else if (mdata->tx_sgl_len) {
479 		mult_delta = mtk_spi_get_mult_delta(mdata->tx_sgl_len);
480 		mdata->xfer_len = mdata->tx_sgl_len - mult_delta;
481 		mdata->tx_sgl_len = mult_delta;
482 	} else if (mdata->rx_sgl_len) {
483 		mult_delta = mtk_spi_get_mult_delta(mdata->rx_sgl_len);
484 		mdata->xfer_len = mdata->rx_sgl_len - mult_delta;
485 		mdata->rx_sgl_len = mult_delta;
486 	}
487 }
488 
mtk_spi_setup_dma_addr(struct spi_master * master,struct spi_transfer * xfer)489 static void mtk_spi_setup_dma_addr(struct spi_master *master,
490 				   struct spi_transfer *xfer)
491 {
492 	struct mtk_spi *mdata = spi_master_get_devdata(master);
493 
494 	if (mdata->tx_sgl) {
495 		writel((u32)(xfer->tx_dma & MTK_SPI_32BITS_MASK),
496 		       mdata->base + SPI_TX_SRC_REG);
497 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
498 		if (mdata->dev_comp->dma_ext)
499 			writel((u32)(xfer->tx_dma >> 32),
500 			       mdata->base + SPI_TX_SRC_REG_64);
501 #endif
502 	}
503 
504 	if (mdata->rx_sgl) {
505 		writel((u32)(xfer->rx_dma & MTK_SPI_32BITS_MASK),
506 		       mdata->base + SPI_RX_DST_REG);
507 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
508 		if (mdata->dev_comp->dma_ext)
509 			writel((u32)(xfer->rx_dma >> 32),
510 			       mdata->base + SPI_RX_DST_REG_64);
511 #endif
512 	}
513 }
514 
mtk_spi_fifo_transfer(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)515 static int mtk_spi_fifo_transfer(struct spi_master *master,
516 				 struct spi_device *spi,
517 				 struct spi_transfer *xfer)
518 {
519 	int cnt, remainder;
520 	u32 reg_val;
521 	struct mtk_spi *mdata = spi_master_get_devdata(master);
522 
523 	mdata->cur_transfer = xfer;
524 	mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, xfer->len);
525 	mdata->num_xfered = 0;
526 	mtk_spi_prepare_transfer(master, xfer);
527 	mtk_spi_setup_packet(master);
528 
529 	if (xfer->tx_buf) {
530 		cnt = xfer->len / 4;
531 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG, xfer->tx_buf, cnt);
532 		remainder = xfer->len % 4;
533 		if (remainder > 0) {
534 			reg_val = 0;
535 			memcpy(&reg_val, xfer->tx_buf + (cnt * 4), remainder);
536 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
537 		}
538 	}
539 
540 	mtk_spi_enable_transfer(master);
541 
542 	return 1;
543 }
544 
mtk_spi_dma_transfer(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)545 static int mtk_spi_dma_transfer(struct spi_master *master,
546 				struct spi_device *spi,
547 				struct spi_transfer *xfer)
548 {
549 	int cmd;
550 	struct mtk_spi *mdata = spi_master_get_devdata(master);
551 
552 	mdata->tx_sgl = NULL;
553 	mdata->rx_sgl = NULL;
554 	mdata->tx_sgl_len = 0;
555 	mdata->rx_sgl_len = 0;
556 	mdata->cur_transfer = xfer;
557 	mdata->num_xfered = 0;
558 
559 	mtk_spi_prepare_transfer(master, xfer);
560 
561 	cmd = readl(mdata->base + SPI_CMD_REG);
562 	if (xfer->tx_buf)
563 		cmd |= SPI_CMD_TX_DMA;
564 	if (xfer->rx_buf)
565 		cmd |= SPI_CMD_RX_DMA;
566 	writel(cmd, mdata->base + SPI_CMD_REG);
567 
568 	if (xfer->tx_buf)
569 		mdata->tx_sgl = xfer->tx_sg.sgl;
570 	if (xfer->rx_buf)
571 		mdata->rx_sgl = xfer->rx_sg.sgl;
572 
573 	if (mdata->tx_sgl) {
574 		xfer->tx_dma = sg_dma_address(mdata->tx_sgl);
575 		mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
576 	}
577 	if (mdata->rx_sgl) {
578 		xfer->rx_dma = sg_dma_address(mdata->rx_sgl);
579 		mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
580 	}
581 
582 	mtk_spi_update_mdata_len(master);
583 	mtk_spi_setup_packet(master);
584 	mtk_spi_setup_dma_addr(master, xfer);
585 	mtk_spi_enable_transfer(master);
586 
587 	return 1;
588 }
589 
mtk_spi_transfer_one(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)590 static int mtk_spi_transfer_one(struct spi_master *master,
591 				struct spi_device *spi,
592 				struct spi_transfer *xfer)
593 {
594 	if (master->can_dma(master, spi, xfer))
595 		return mtk_spi_dma_transfer(master, spi, xfer);
596 	else
597 		return mtk_spi_fifo_transfer(master, spi, xfer);
598 }
599 
mtk_spi_can_dma(struct spi_master * master,struct spi_device * spi,struct spi_transfer * xfer)600 static bool mtk_spi_can_dma(struct spi_master *master,
601 			    struct spi_device *spi,
602 			    struct spi_transfer *xfer)
603 {
604 	/* Buffers for DMA transactions must be 4-byte aligned */
605 	return (xfer->len > MTK_SPI_MAX_FIFO_SIZE &&
606 		(unsigned long)xfer->tx_buf % 4 == 0 &&
607 		(unsigned long)xfer->rx_buf % 4 == 0);
608 }
609 
mtk_spi_setup(struct spi_device * spi)610 static int mtk_spi_setup(struct spi_device *spi)
611 {
612 	struct mtk_spi *mdata = spi_master_get_devdata(spi->master);
613 
614 	if (!spi->controller_data)
615 		spi->controller_data = (void *)&mtk_default_chip_info;
616 
617 	if (mdata->dev_comp->need_pad_sel && gpio_is_valid(spi->cs_gpio))
618 		gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
619 
620 	return 0;
621 }
622 
mtk_spi_interrupt(int irq,void * dev_id)623 static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id)
624 {
625 	u32 cmd, reg_val, cnt, remainder, len;
626 	struct spi_master *master = dev_id;
627 	struct mtk_spi *mdata = spi_master_get_devdata(master);
628 	struct spi_transfer *trans = mdata->cur_transfer;
629 
630 	reg_val = readl(mdata->base + SPI_STATUS0_REG);
631 	if (reg_val & MTK_SPI_PAUSE_INT_STATUS)
632 		mdata->state = MTK_SPI_PAUSED;
633 	else
634 		mdata->state = MTK_SPI_IDLE;
635 
636 	if (!master->can_dma(master, NULL, trans)) {
637 		if (trans->rx_buf) {
638 			cnt = mdata->xfer_len / 4;
639 			ioread32_rep(mdata->base + SPI_RX_DATA_REG,
640 				     trans->rx_buf + mdata->num_xfered, cnt);
641 			remainder = mdata->xfer_len % 4;
642 			if (remainder > 0) {
643 				reg_val = readl(mdata->base + SPI_RX_DATA_REG);
644 				memcpy(trans->rx_buf +
645 					mdata->num_xfered +
646 					(cnt * 4),
647 					&reg_val,
648 					remainder);
649 			}
650 		}
651 
652 		mdata->num_xfered += mdata->xfer_len;
653 		if (mdata->num_xfered == trans->len) {
654 			spi_finalize_current_transfer(master);
655 			return IRQ_HANDLED;
656 		}
657 
658 		len = trans->len - mdata->num_xfered;
659 		mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len);
660 		mtk_spi_setup_packet(master);
661 
662 		cnt = mdata->xfer_len / 4;
663 		iowrite32_rep(mdata->base + SPI_TX_DATA_REG,
664 				trans->tx_buf + mdata->num_xfered, cnt);
665 
666 		remainder = mdata->xfer_len % 4;
667 		if (remainder > 0) {
668 			reg_val = 0;
669 			memcpy(&reg_val,
670 				trans->tx_buf + (cnt * 4) + mdata->num_xfered,
671 				remainder);
672 			writel(reg_val, mdata->base + SPI_TX_DATA_REG);
673 		}
674 
675 		mtk_spi_enable_transfer(master);
676 
677 		return IRQ_HANDLED;
678 	}
679 
680 	if (mdata->tx_sgl)
681 		trans->tx_dma += mdata->xfer_len;
682 	if (mdata->rx_sgl)
683 		trans->rx_dma += mdata->xfer_len;
684 
685 	if (mdata->tx_sgl && (mdata->tx_sgl_len == 0)) {
686 		mdata->tx_sgl = sg_next(mdata->tx_sgl);
687 		if (mdata->tx_sgl) {
688 			trans->tx_dma = sg_dma_address(mdata->tx_sgl);
689 			mdata->tx_sgl_len = sg_dma_len(mdata->tx_sgl);
690 		}
691 	}
692 	if (mdata->rx_sgl && (mdata->rx_sgl_len == 0)) {
693 		mdata->rx_sgl = sg_next(mdata->rx_sgl);
694 		if (mdata->rx_sgl) {
695 			trans->rx_dma = sg_dma_address(mdata->rx_sgl);
696 			mdata->rx_sgl_len = sg_dma_len(mdata->rx_sgl);
697 		}
698 	}
699 
700 	if (!mdata->tx_sgl && !mdata->rx_sgl) {
701 		/* spi disable dma */
702 		cmd = readl(mdata->base + SPI_CMD_REG);
703 		cmd &= ~SPI_CMD_TX_DMA;
704 		cmd &= ~SPI_CMD_RX_DMA;
705 		writel(cmd, mdata->base + SPI_CMD_REG);
706 
707 		spi_finalize_current_transfer(master);
708 		return IRQ_HANDLED;
709 	}
710 
711 	mtk_spi_update_mdata_len(master);
712 	mtk_spi_setup_packet(master);
713 	mtk_spi_setup_dma_addr(master, trans);
714 	mtk_spi_enable_transfer(master);
715 
716 	return IRQ_HANDLED;
717 }
718 
mtk_spi_probe(struct platform_device * pdev)719 static int mtk_spi_probe(struct platform_device *pdev)
720 {
721 	struct spi_master *master;
722 	struct mtk_spi *mdata;
723 	const struct of_device_id *of_id;
724 	int i, irq, ret, addr_bits;
725 
726 	master = spi_alloc_master(&pdev->dev, sizeof(*mdata));
727 	if (!master) {
728 		dev_err(&pdev->dev, "failed to alloc spi master\n");
729 		return -ENOMEM;
730 	}
731 
732 	master->auto_runtime_pm = true;
733 	master->dev.of_node = pdev->dev.of_node;
734 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
735 
736 	master->set_cs = mtk_spi_set_cs;
737 	master->prepare_message = mtk_spi_prepare_message;
738 	master->transfer_one = mtk_spi_transfer_one;
739 	master->can_dma = mtk_spi_can_dma;
740 	master->setup = mtk_spi_setup;
741 	master->set_cs_timing = mtk_spi_set_hw_cs_timing;
742 
743 	of_id = of_match_node(mtk_spi_of_match, pdev->dev.of_node);
744 	if (!of_id) {
745 		dev_err(&pdev->dev, "failed to probe of_node\n");
746 		ret = -EINVAL;
747 		goto err_put_master;
748 	}
749 
750 	mdata = spi_master_get_devdata(master);
751 	mdata->dev_comp = of_id->data;
752 
753 	if (mdata->dev_comp->enhance_timing)
754 		master->mode_bits |= SPI_CS_HIGH;
755 
756 	if (mdata->dev_comp->must_tx)
757 		master->flags = SPI_MASTER_MUST_TX;
758 
759 	if (mdata->dev_comp->need_pad_sel) {
760 		mdata->pad_num = of_property_count_u32_elems(
761 			pdev->dev.of_node,
762 			"mediatek,pad-select");
763 		if (mdata->pad_num < 0) {
764 			dev_err(&pdev->dev,
765 				"No 'mediatek,pad-select' property\n");
766 			ret = -EINVAL;
767 			goto err_put_master;
768 		}
769 
770 		mdata->pad_sel = devm_kmalloc_array(&pdev->dev, mdata->pad_num,
771 						    sizeof(u32), GFP_KERNEL);
772 		if (!mdata->pad_sel) {
773 			ret = -ENOMEM;
774 			goto err_put_master;
775 		}
776 
777 		for (i = 0; i < mdata->pad_num; i++) {
778 			of_property_read_u32_index(pdev->dev.of_node,
779 						   "mediatek,pad-select",
780 						   i, &mdata->pad_sel[i]);
781 			if (mdata->pad_sel[i] > MT8173_SPI_MAX_PAD_SEL) {
782 				dev_err(&pdev->dev, "wrong pad-sel[%d]: %u\n",
783 					i, mdata->pad_sel[i]);
784 				ret = -EINVAL;
785 				goto err_put_master;
786 			}
787 		}
788 	}
789 
790 	platform_set_drvdata(pdev, master);
791 	mdata->base = devm_platform_ioremap_resource(pdev, 0);
792 	if (IS_ERR(mdata->base)) {
793 		ret = PTR_ERR(mdata->base);
794 		goto err_put_master;
795 	}
796 
797 	irq = platform_get_irq(pdev, 0);
798 	if (irq < 0) {
799 		ret = irq;
800 		goto err_put_master;
801 	}
802 
803 	if (!pdev->dev.dma_mask)
804 		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
805 
806 	ret = devm_request_irq(&pdev->dev, irq, mtk_spi_interrupt,
807 			       IRQF_TRIGGER_NONE, dev_name(&pdev->dev), master);
808 	if (ret) {
809 		dev_err(&pdev->dev, "failed to register irq (%d)\n", ret);
810 		goto err_put_master;
811 	}
812 
813 	mdata->parent_clk = devm_clk_get(&pdev->dev, "parent-clk");
814 	if (IS_ERR(mdata->parent_clk)) {
815 		ret = PTR_ERR(mdata->parent_clk);
816 		dev_err(&pdev->dev, "failed to get parent-clk: %d\n", ret);
817 		goto err_put_master;
818 	}
819 
820 	mdata->sel_clk = devm_clk_get(&pdev->dev, "sel-clk");
821 	if (IS_ERR(mdata->sel_clk)) {
822 		ret = PTR_ERR(mdata->sel_clk);
823 		dev_err(&pdev->dev, "failed to get sel-clk: %d\n", ret);
824 		goto err_put_master;
825 	}
826 
827 	mdata->spi_clk = devm_clk_get(&pdev->dev, "spi-clk");
828 	if (IS_ERR(mdata->spi_clk)) {
829 		ret = PTR_ERR(mdata->spi_clk);
830 		dev_err(&pdev->dev, "failed to get spi-clk: %d\n", ret);
831 		goto err_put_master;
832 	}
833 
834 	ret = clk_prepare_enable(mdata->spi_clk);
835 	if (ret < 0) {
836 		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
837 		goto err_put_master;
838 	}
839 
840 	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
841 	if (ret < 0) {
842 		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
843 		clk_disable_unprepare(mdata->spi_clk);
844 		goto err_put_master;
845 	}
846 
847 	mdata->spi_clk_hz = clk_get_rate(mdata->spi_clk);
848 
849 	if (mdata->dev_comp->no_need_unprepare)
850 		clk_disable(mdata->spi_clk);
851 	else
852 		clk_disable_unprepare(mdata->spi_clk);
853 
854 	pm_runtime_enable(&pdev->dev);
855 
856 	if (mdata->dev_comp->need_pad_sel) {
857 		if (mdata->pad_num != master->num_chipselect) {
858 			dev_err(&pdev->dev,
859 				"pad_num does not match num_chipselect(%d != %d)\n",
860 				mdata->pad_num, master->num_chipselect);
861 			ret = -EINVAL;
862 			goto err_disable_runtime_pm;
863 		}
864 
865 		if (!master->cs_gpios && master->num_chipselect > 1) {
866 			dev_err(&pdev->dev,
867 				"cs_gpios not specified and num_chipselect > 1\n");
868 			ret = -EINVAL;
869 			goto err_disable_runtime_pm;
870 		}
871 
872 		if (master->cs_gpios) {
873 			for (i = 0; i < master->num_chipselect; i++) {
874 				ret = devm_gpio_request(&pdev->dev,
875 							master->cs_gpios[i],
876 							dev_name(&pdev->dev));
877 				if (ret) {
878 					dev_err(&pdev->dev,
879 						"can't get CS GPIO %i\n", i);
880 					goto err_disable_runtime_pm;
881 				}
882 			}
883 		}
884 	}
885 
886 	if (mdata->dev_comp->dma_ext)
887 		addr_bits = DMA_ADDR_EXT_BITS;
888 	else
889 		addr_bits = DMA_ADDR_DEF_BITS;
890 	ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(addr_bits));
891 	if (ret)
892 		dev_notice(&pdev->dev, "SPI dma_set_mask(%d) failed, ret:%d\n",
893 			   addr_bits, ret);
894 
895 	ret = devm_spi_register_master(&pdev->dev, master);
896 	if (ret) {
897 		dev_err(&pdev->dev, "failed to register master (%d)\n", ret);
898 		goto err_disable_runtime_pm;
899 	}
900 
901 	return 0;
902 
903 err_disable_runtime_pm:
904 	pm_runtime_disable(&pdev->dev);
905 err_put_master:
906 	spi_master_put(master);
907 
908 	return ret;
909 }
910 
mtk_spi_remove(struct platform_device * pdev)911 static int mtk_spi_remove(struct platform_device *pdev)
912 {
913 	struct spi_master *master = platform_get_drvdata(pdev);
914 	struct mtk_spi *mdata = spi_master_get_devdata(master);
915 	int ret;
916 
917 	ret = pm_runtime_resume_and_get(&pdev->dev);
918 	if (ret < 0)
919 		return ret;
920 
921 	mtk_spi_reset(mdata);
922 
923 	if (mdata->dev_comp->no_need_unprepare)
924 		clk_unprepare(mdata->spi_clk);
925 
926 	pm_runtime_put_noidle(&pdev->dev);
927 	pm_runtime_disable(&pdev->dev);
928 
929 	return 0;
930 }
931 
932 #ifdef CONFIG_PM_SLEEP
mtk_spi_suspend(struct device * dev)933 static int mtk_spi_suspend(struct device *dev)
934 {
935 	int ret;
936 	struct spi_master *master = dev_get_drvdata(dev);
937 	struct mtk_spi *mdata = spi_master_get_devdata(master);
938 
939 	ret = spi_master_suspend(master);
940 	if (ret)
941 		return ret;
942 
943 	if (!pm_runtime_suspended(dev))
944 		clk_disable_unprepare(mdata->spi_clk);
945 
946 	return ret;
947 }
948 
mtk_spi_resume(struct device * dev)949 static int mtk_spi_resume(struct device *dev)
950 {
951 	int ret;
952 	struct spi_master *master = dev_get_drvdata(dev);
953 	struct mtk_spi *mdata = spi_master_get_devdata(master);
954 
955 	if (!pm_runtime_suspended(dev)) {
956 		ret = clk_prepare_enable(mdata->spi_clk);
957 		if (ret < 0) {
958 			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
959 			return ret;
960 		}
961 	}
962 
963 	ret = spi_master_resume(master);
964 	if (ret < 0)
965 		clk_disable_unprepare(mdata->spi_clk);
966 
967 	return ret;
968 }
969 #endif /* CONFIG_PM_SLEEP */
970 
971 #ifdef CONFIG_PM
mtk_spi_runtime_suspend(struct device * dev)972 static int mtk_spi_runtime_suspend(struct device *dev)
973 {
974 	struct spi_master *master = dev_get_drvdata(dev);
975 	struct mtk_spi *mdata = spi_master_get_devdata(master);
976 
977 	if (mdata->dev_comp->no_need_unprepare)
978 		clk_disable(mdata->spi_clk);
979 	else
980 		clk_disable_unprepare(mdata->spi_clk);
981 
982 	return 0;
983 }
984 
mtk_spi_runtime_resume(struct device * dev)985 static int mtk_spi_runtime_resume(struct device *dev)
986 {
987 	struct spi_master *master = dev_get_drvdata(dev);
988 	struct mtk_spi *mdata = spi_master_get_devdata(master);
989 	int ret;
990 
991 	if (mdata->dev_comp->no_need_unprepare)
992 		ret = clk_enable(mdata->spi_clk);
993 	else
994 		ret = clk_prepare_enable(mdata->spi_clk);
995 	if (ret < 0) {
996 		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
997 		return ret;
998 	}
999 
1000 	return 0;
1001 }
1002 #endif /* CONFIG_PM */
1003 
1004 static const struct dev_pm_ops mtk_spi_pm = {
1005 	SET_SYSTEM_SLEEP_PM_OPS(mtk_spi_suspend, mtk_spi_resume)
1006 	SET_RUNTIME_PM_OPS(mtk_spi_runtime_suspend,
1007 			   mtk_spi_runtime_resume, NULL)
1008 };
1009 
1010 static struct platform_driver mtk_spi_driver = {
1011 	.driver = {
1012 		.name = "mtk-spi",
1013 		.pm	= &mtk_spi_pm,
1014 		.of_match_table = mtk_spi_of_match,
1015 	},
1016 	.probe = mtk_spi_probe,
1017 	.remove = mtk_spi_remove,
1018 };
1019 
1020 module_platform_driver(mtk_spi_driver);
1021 
1022 MODULE_DESCRIPTION("MTK SPI Controller driver");
1023 MODULE_AUTHOR("Leilk Liu <leilk.liu@mediatek.com>");
1024 MODULE_LICENSE("GPL v2");
1025 MODULE_ALIAS("platform:mtk-spi");
1026