1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright (c) 2021 Sunplus Inc.
3 // Author: Li-hao Kuo <lhjeff911@gmail.com>
4 
5 #include <linux/bitfield.h>
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/interrupt.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/reset.h>
15 #include <linux/spi/spi.h>
16 
17 #define SP7021_DATA_RDY_REG		0x0044
18 #define SP7021_SLAVE_DMA_CTRL_REG	0x0048
19 #define SP7021_SLAVE_DMA_LENGTH_REG	0x004c
20 #define SP7021_SLAVE_DMA_ADDR_REG	0x004c
21 
22 #define SP7021_SLAVE_DATA_RDY		BIT(0)
23 #define SP7021_SLAVE_SW_RST		BIT(1)
24 #define SP7021_SLA_DMA_W_INT		BIT(8)
25 #define SP7021_SLAVE_CLR_INT		BIT(8)
26 #define SP7021_SLAVE_DMA_EN		BIT(0)
27 #define SP7021_SLAVE_DMA_RW		BIT(6)
28 #define SP7021_SLAVE_DMA_CMD		GENMASK(3, 2)
29 
30 #define SP7021_FIFO_REG			0x0034
31 #define SP7021_SPI_STATUS_REG		0x0038
32 #define SP7021_SPI_CONFIG_REG		0x003c
33 #define SP7021_INT_BUSY_REG		0x004c
34 #define SP7021_DMA_CTRL_REG		0x0050
35 
36 #define SP7021_SPI_START_FD		BIT(0)
37 #define SP7021_FD_SW_RST		BIT(1)
38 #define SP7021_TX_EMP_FLAG		BIT(2)
39 #define SP7021_RX_EMP_FLAG		BIT(4)
40 #define SP7021_RX_FULL_FLAG		BIT(5)
41 #define SP7021_FINISH_FLAG		BIT(6)
42 
43 #define SP7021_TX_CNT_MASK		GENMASK(11, 8)
44 #define SP7021_RX_CNT_MASK		GENMASK(15, 12)
45 #define SP7021_TX_LEN_MASK		GENMASK(23, 16)
46 #define SP7021_GET_LEN_MASK		GENMASK(31, 24)
47 #define SP7021_SET_TX_LEN		GENMASK(23, 16)
48 #define SP7021_SET_XFER_LEN		GENMASK(31, 24)
49 
50 #define SP7021_CPOL_FD			BIT(0)
51 #define SP7021_CPHA_R			BIT(1)
52 #define SP7021_CPHA_W			BIT(2)
53 #define SP7021_LSB_SEL			BIT(4)
54 #define SP7021_CS_POR			BIT(5)
55 #define SP7021_FD_SEL			BIT(6)
56 
57 #define SP7021_RX_UNIT			GENMASK(8, 7)
58 #define SP7021_TX_UNIT			GENMASK(10, 9)
59 #define SP7021_TX_EMP_FLAG_MASK		BIT(11)
60 #define SP7021_RX_FULL_FLAG_MASK	BIT(14)
61 #define SP7021_FINISH_FLAG_MASK		BIT(15)
62 #define SP7021_CLEAN_RW_BYTE		GENMASK(10, 7)
63 #define SP7021_CLEAN_FLUG_MASK		GENMASK(15, 11)
64 #define SP7021_CLK_MASK			GENMASK(31, 16)
65 
66 #define SP7021_INT_BYPASS		BIT(3)
67 #define SP7021_CLR_MASTER_INT		BIT(6)
68 
69 #define SP7021_SPI_DATA_SIZE		(255)
70 #define SP7021_FIFO_DATA_LEN		(16)
71 
72 enum {
73 	SP7021_MASTER_MODE = 0,
74 	SP7021_SLAVE_MODE = 1,
75 };
76 
77 struct sp7021_spi_ctlr {
78 	struct device *dev;
79 	struct spi_controller *ctlr;
80 	void __iomem *m_base;
81 	void __iomem *s_base;
82 	u32 xfer_conf;
83 	int mode;
84 	int m_irq;
85 	int s_irq;
86 	struct clk *spi_clk;
87 	struct reset_control *rstc;
88 	// data xfer lock
89 	struct mutex buf_lock;
90 	struct completion isr_done;
91 	struct completion slave_isr;
92 	unsigned int  rx_cur_len;
93 	unsigned int  tx_cur_len;
94 	unsigned int  data_unit;
95 	const u8 *tx_buf;
96 	u8 *rx_buf;
97 };
98 
99 static irqreturn_t sp7021_spi_slave_irq(int irq, void *dev)
100 {
101 	struct sp7021_spi_ctlr *pspim = dev;
102 	unsigned int data_status;
103 
104 	data_status = readl(pspim->s_base + SP7021_DATA_RDY_REG);
105 	data_status |= SP7021_SLAVE_CLR_INT;
106 	writel(data_status , pspim->s_base + SP7021_DATA_RDY_REG);
107 	complete(&pspim->slave_isr);
108 	return IRQ_HANDLED;
109 }
110 
111 static int sp7021_spi_slave_abort(struct spi_controller *ctlr)
112 {
113 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
114 
115 	complete(&pspim->slave_isr);
116 	complete(&pspim->isr_done);
117 	return 0;
118 }
119 
120 static int sp7021_spi_slave_tx(struct spi_device *spi, struct spi_transfer *xfer)
121 {
122 	struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
123 	u32 value;
124 
125 	reinit_completion(&pspim->slave_isr);
126 	value = SP7021_SLAVE_DMA_EN | SP7021_SLAVE_DMA_RW | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
127 	writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
128 	writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
129 	writel(xfer->tx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
130 	value = readl(pspim->s_base + SP7021_DATA_RDY_REG);
131 	value |= SP7021_SLAVE_DATA_RDY;
132 	writel(value, pspim->s_base + SP7021_DATA_RDY_REG);
133 	if (wait_for_completion_interruptible(&pspim->isr_done)) {
134 		dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
135 		return -EINTR;
136 	}
137 	return 0;
138 }
139 
140 static int sp7021_spi_slave_rx(struct spi_device *spi, struct spi_transfer *xfer)
141 {
142 	struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
143 	u32 value;
144 
145 	reinit_completion(&pspim->isr_done);
146 	value = SP7021_SLAVE_DMA_EN | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
147 	writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
148 	writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
149 	writel(xfer->rx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
150 	if (wait_for_completion_interruptible(&pspim->isr_done)) {
151 		dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
152 		return -EINTR;
153 	}
154 	writel(SP7021_SLAVE_SW_RST, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
155 	return 0;
156 }
157 
158 static void sp7021_spi_master_rb(struct sp7021_spi_ctlr *pspim, unsigned int len)
159 {
160 	int i;
161 
162 	for (i = 0; i < len; i++) {
163 		pspim->rx_buf[pspim->rx_cur_len] =
164 			readl(pspim->m_base + SP7021_FIFO_REG);
165 		pspim->rx_cur_len++;
166 	}
167 }
168 
169 static void sp7021_spi_master_wb(struct sp7021_spi_ctlr *pspim, unsigned int len)
170 {
171 	int i;
172 
173 	for (i = 0; i < len; i++) {
174 		writel(pspim->tx_buf[pspim->tx_cur_len],
175 		       pspim->m_base + SP7021_FIFO_REG);
176 		pspim->tx_cur_len++;
177 	}
178 }
179 
180 static irqreturn_t sp7021_spi_master_irq(int irq, void *dev)
181 {
182 	struct sp7021_spi_ctlr *pspim = dev;
183 	unsigned int tx_cnt, total_len;
184 	unsigned int tx_len, rx_cnt;
185 	unsigned int fd_status;
186 	bool isrdone = false;
187 	u32 value;
188 
189 	fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
190 	tx_cnt = FIELD_GET(SP7021_TX_CNT_MASK, fd_status);
191 	tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
192 	total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
193 
194 	if ((fd_status & SP7021_TX_EMP_FLAG) && (fd_status & SP7021_RX_EMP_FLAG) && total_len == 0)
195 		return IRQ_NONE;
196 
197 	if (tx_len == 0 && total_len == 0)
198 		return IRQ_NONE;
199 
200 	rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
201 	if (fd_status & SP7021_RX_FULL_FLAG)
202 		rx_cnt = pspim->data_unit;
203 
204 	tx_cnt = min(tx_len - pspim->tx_cur_len, pspim->data_unit - tx_cnt);
205 	dev_dbg(pspim->dev, "fd_st=0x%x rx_c:%d tx_c:%d tx_l:%d",
206 		fd_status, rx_cnt, tx_cnt, tx_len);
207 
208 	if (rx_cnt > 0)
209 		sp7021_spi_master_rb(pspim, rx_cnt);
210 	if (tx_cnt > 0)
211 		sp7021_spi_master_wb(pspim, tx_cnt);
212 
213 	fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
214 	tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
215 	total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
216 
217 	if (fd_status & SP7021_FINISH_FLAG || tx_len == pspim->tx_cur_len) {
218 		while (total_len != pspim->rx_cur_len) {
219 			fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
220 			total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
221 			if (fd_status & SP7021_RX_FULL_FLAG)
222 				rx_cnt = pspim->data_unit;
223 			else
224 				rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
225 
226 			if (rx_cnt > 0)
227 				sp7021_spi_master_rb(pspim, rx_cnt);
228 		}
229 		value = readl(pspim->m_base + SP7021_INT_BUSY_REG);
230 		value |= SP7021_CLR_MASTER_INT;
231 		writel(value, pspim->m_base + SP7021_INT_BUSY_REG);
232 		writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
233 		isrdone = true;
234 	}
235 
236 	if (isrdone)
237 		complete(&pspim->isr_done);
238 	return IRQ_HANDLED;
239 }
240 
241 static void sp7021_prep_transfer(struct spi_controller *ctlr, struct spi_device *spi)
242 {
243 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
244 
245 	pspim->tx_cur_len = 0;
246 	pspim->rx_cur_len = 0;
247 	pspim->data_unit = SP7021_FIFO_DATA_LEN;
248 }
249 
250 // preliminary set CS, CPOL, CPHA and LSB
251 static int sp7021_spi_controller_prepare_message(struct spi_controller *ctlr,
252 						 struct spi_message *msg)
253 {
254 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
255 	struct spi_device *s = msg->spi;
256 	u32 valus, rs = 0;
257 
258 	valus = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
259 	valus |= SP7021_FD_SW_RST;
260 	writel(valus, pspim->m_base + SP7021_SPI_STATUS_REG);
261 	rs |= SP7021_FD_SEL;
262 	if (s->mode & SPI_CPOL)
263 		rs |= SP7021_CPOL_FD;
264 
265 	if (s->mode & SPI_LSB_FIRST)
266 		rs |= SP7021_LSB_SEL;
267 
268 	if (s->mode & SPI_CS_HIGH)
269 		rs |= SP7021_CS_POR;
270 
271 	if (s->mode & SPI_CPHA)
272 		rs |=  SP7021_CPHA_R;
273 	else
274 		rs |=  SP7021_CPHA_W;
275 
276 	rs |=  FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
277 	pspim->xfer_conf = rs;
278 	if (pspim->xfer_conf & SP7021_CPOL_FD)
279 		writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
280 
281 	return 0;
282 }
283 
284 static void sp7021_spi_setup_clk(struct spi_controller *ctlr, struct spi_transfer *xfer)
285 {
286 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
287 	u32 clk_rate, clk_sel, div;
288 
289 	clk_rate = clk_get_rate(pspim->spi_clk);
290 	div = max(2U, clk_rate / xfer->speed_hz);
291 
292 	clk_sel = (div / 2) - 1;
293 	pspim->xfer_conf &= ~SP7021_CLK_MASK;
294 	pspim->xfer_conf |= FIELD_PREP(SP7021_CLK_MASK, clk_sel);
295 	writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
296 }
297 
298 static int sp7021_spi_master_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
299 				       struct spi_transfer *xfer)
300 {
301 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
302 	unsigned long timeout = msecs_to_jiffies(1000);
303 	unsigned int xfer_cnt, xfer_len, last_len;
304 	unsigned int i, len_temp;
305 	u32 reg_temp;
306 
307 	xfer_cnt = xfer->len / SP7021_SPI_DATA_SIZE;
308 	last_len = xfer->len % SP7021_SPI_DATA_SIZE;
309 
310 	for (i = 0; i <= xfer_cnt; i++) {
311 		mutex_lock(&pspim->buf_lock);
312 		sp7021_prep_transfer(ctlr, spi);
313 		sp7021_spi_setup_clk(ctlr, xfer);
314 		reinit_completion(&pspim->isr_done);
315 
316 		if (i == xfer_cnt)
317 			xfer_len = last_len;
318 		else
319 			xfer_len = SP7021_SPI_DATA_SIZE;
320 
321 		pspim->tx_buf = xfer->tx_buf + i * SP7021_SPI_DATA_SIZE;
322 		pspim->rx_buf = xfer->rx_buf + i * SP7021_SPI_DATA_SIZE;
323 
324 		if (pspim->tx_cur_len < xfer_len) {
325 			len_temp = min(pspim->data_unit, xfer_len);
326 			sp7021_spi_master_wb(pspim, len_temp);
327 		}
328 		reg_temp = readl(pspim->m_base + SP7021_SPI_CONFIG_REG);
329 		reg_temp &= ~SP7021_CLEAN_RW_BYTE;
330 		reg_temp &= ~SP7021_CLEAN_FLUG_MASK;
331 		reg_temp |= SP7021_FD_SEL | SP7021_FINISH_FLAG_MASK |
332 			    SP7021_TX_EMP_FLAG_MASK | SP7021_RX_FULL_FLAG_MASK |
333 			    FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
334 		writel(reg_temp, pspim->m_base + SP7021_SPI_CONFIG_REG);
335 
336 		reg_temp = FIELD_PREP(SP7021_SET_TX_LEN, xfer_len) |
337 				      FIELD_PREP(SP7021_SET_XFER_LEN, xfer_len) |
338 				      SP7021_SPI_START_FD;
339 		writel(reg_temp, pspim->m_base + SP7021_SPI_STATUS_REG);
340 
341 		if (!wait_for_completion_interruptible_timeout(&pspim->isr_done, timeout)) {
342 			dev_err(&spi->dev, "wait_for_completion err\n");
343 			mutex_unlock(&pspim->buf_lock);
344 			return -ETIMEDOUT;
345 		}
346 
347 		reg_temp = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
348 		if (reg_temp & SP7021_FINISH_FLAG) {
349 			writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
350 			writel(readl(pspim->m_base + SP7021_SPI_CONFIG_REG) &
351 				SP7021_CLEAN_FLUG_MASK, pspim->m_base + SP7021_SPI_CONFIG_REG);
352 		}
353 
354 		if (pspim->xfer_conf & SP7021_CPOL_FD)
355 			writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
356 
357 		mutex_unlock(&pspim->buf_lock);
358 	}
359 	return 0;
360 }
361 
362 static int sp7021_spi_slave_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
363 				       struct spi_transfer *xfer)
364 {
365 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
366 	struct device *dev = pspim->dev;
367 	int ret;
368 
369 	if (xfer->tx_buf && !xfer->rx_buf) {
370 		xfer->tx_dma = dma_map_single(dev, (void *)xfer->tx_buf,
371 					      xfer->len, DMA_TO_DEVICE);
372 		if (dma_mapping_error(dev, xfer->tx_dma))
373 			return -ENOMEM;
374 		ret = sp7021_spi_slave_tx(spi, xfer);
375 		dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE);
376 	} else if (xfer->rx_buf && !xfer->tx_buf) {
377 		xfer->rx_dma = dma_map_single(dev, xfer->rx_buf, xfer->len,
378 					      DMA_FROM_DEVICE);
379 		if (dma_mapping_error(dev, xfer->rx_dma))
380 			return -ENOMEM;
381 		ret = sp7021_spi_slave_rx(spi, xfer);
382 		dma_unmap_single(dev, xfer->rx_dma, xfer->len, DMA_FROM_DEVICE);
383 	} else {
384 		dev_dbg(&ctlr->dev, "%s() wrong command\n", __func__);
385 		return -EINVAL;
386 	}
387 
388 	spi_finalize_current_transfer(ctlr);
389 	return ret;
390 }
391 
392 static void sp7021_spi_disable_unprepare(void *data)
393 {
394 	clk_disable_unprepare(data);
395 }
396 
397 static void sp7021_spi_reset_control_assert(void *data)
398 {
399 	reset_control_assert(data);
400 }
401 
402 static int sp7021_spi_controller_probe(struct platform_device *pdev)
403 {
404 	struct device *dev = &pdev->dev;
405 	struct sp7021_spi_ctlr *pspim;
406 	struct spi_controller *ctlr;
407 	int mode, ret;
408 
409 	pdev->id = of_alias_get_id(pdev->dev.of_node, "sp_spi");
410 
411 	if (device_property_read_bool(dev, "spi-slave"))
412 		mode = SP7021_SLAVE_MODE;
413 	else
414 		mode = SP7021_MASTER_MODE;
415 
416 	if (mode == SP7021_SLAVE_MODE)
417 		ctlr = devm_spi_alloc_slave(dev, sizeof(*pspim));
418 	else
419 		ctlr = devm_spi_alloc_master(dev, sizeof(*pspim));
420 	if (!ctlr)
421 		return -ENOMEM;
422 	device_set_node(&ctlr->dev, dev_fwnode(dev));
423 	ctlr->bus_num = pdev->id;
424 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
425 	ctlr->auto_runtime_pm = true;
426 	ctlr->prepare_message = sp7021_spi_controller_prepare_message;
427 	if (mode == SP7021_SLAVE_MODE) {
428 		ctlr->transfer_one = sp7021_spi_slave_transfer_one;
429 		ctlr->slave_abort = sp7021_spi_slave_abort;
430 		ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
431 	} else {
432 		ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
433 		ctlr->min_speed_hz = 40000;
434 		ctlr->max_speed_hz = 25000000;
435 		ctlr->use_gpio_descriptors = true;
436 		ctlr->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
437 		ctlr->transfer_one = sp7021_spi_master_transfer_one;
438 	}
439 	platform_set_drvdata(pdev, ctlr);
440 	pspim = spi_controller_get_devdata(ctlr);
441 	pspim->mode = mode;
442 	pspim->ctlr = ctlr;
443 	pspim->dev = dev;
444 	mutex_init(&pspim->buf_lock);
445 	init_completion(&pspim->isr_done);
446 	init_completion(&pspim->slave_isr);
447 
448 	pspim->m_base = devm_platform_ioremap_resource_byname(pdev, "master");
449 	if (IS_ERR(pspim->m_base))
450 		return dev_err_probe(dev, PTR_ERR(pspim->m_base), "m_base get fail\n");
451 
452 	pspim->s_base = devm_platform_ioremap_resource_byname(pdev, "slave");
453 	if (IS_ERR(pspim->s_base))
454 		return dev_err_probe(dev, PTR_ERR(pspim->s_base), "s_base get fail\n");
455 
456 	pspim->m_irq = platform_get_irq_byname(pdev, "master_risc");
457 	if (pspim->m_irq < 0)
458 		return pspim->m_irq;
459 
460 	pspim->s_irq = platform_get_irq_byname(pdev, "slave_risc");
461 	if (pspim->s_irq < 0)
462 		return pspim->s_irq;
463 
464 	pspim->spi_clk = devm_clk_get(dev, NULL);
465 	if (IS_ERR(pspim->spi_clk))
466 		return dev_err_probe(dev, PTR_ERR(pspim->spi_clk), "clk get fail\n");
467 
468 	pspim->rstc = devm_reset_control_get_exclusive(dev, NULL);
469 	if (IS_ERR(pspim->rstc))
470 		return dev_err_probe(dev, PTR_ERR(pspim->rstc), "rst get fail\n");
471 
472 	ret = clk_prepare_enable(pspim->spi_clk);
473 	if (ret)
474 		return dev_err_probe(dev, ret, "failed to enable clk\n");
475 
476 	ret = devm_add_action_or_reset(dev, sp7021_spi_disable_unprepare, pspim->spi_clk);
477 	if (ret)
478 		return ret;
479 
480 	ret = reset_control_deassert(pspim->rstc);
481 	if (ret)
482 		return dev_err_probe(dev, ret, "failed to deassert reset\n");
483 
484 	ret = devm_add_action_or_reset(dev, sp7021_spi_reset_control_assert, pspim->rstc);
485 	if (ret)
486 		return ret;
487 
488 	ret = devm_request_irq(dev, pspim->m_irq, sp7021_spi_master_irq,
489 			       IRQF_TRIGGER_RISING, pdev->name, pspim);
490 	if (ret)
491 		return ret;
492 
493 	ret = devm_request_irq(dev, pspim->s_irq, sp7021_spi_slave_irq,
494 			       IRQF_TRIGGER_RISING, pdev->name, pspim);
495 	if (ret)
496 		return ret;
497 
498 	pm_runtime_enable(dev);
499 	ret = spi_register_controller(ctlr);
500 	if (ret) {
501 		pm_runtime_disable(dev);
502 		return dev_err_probe(dev, ret, "spi_register_master fail\n");
503 	}
504 	return 0;
505 }
506 
507 static void sp7021_spi_controller_remove(struct platform_device *pdev)
508 {
509 	struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
510 
511 	spi_unregister_controller(ctlr);
512 	pm_runtime_disable(&pdev->dev);
513 	pm_runtime_set_suspended(&pdev->dev);
514 }
515 
516 static int __maybe_unused sp7021_spi_controller_suspend(struct device *dev)
517 {
518 	struct spi_controller *ctlr = dev_get_drvdata(dev);
519 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
520 
521 	return reset_control_assert(pspim->rstc);
522 }
523 
524 static int __maybe_unused sp7021_spi_controller_resume(struct device *dev)
525 {
526 	struct spi_controller *ctlr = dev_get_drvdata(dev);
527 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
528 
529 	reset_control_deassert(pspim->rstc);
530 	return clk_prepare_enable(pspim->spi_clk);
531 }
532 
533 #ifdef CONFIG_PM
534 static int sp7021_spi_runtime_suspend(struct device *dev)
535 {
536 	struct spi_controller *ctlr = dev_get_drvdata(dev);
537 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
538 
539 	return reset_control_assert(pspim->rstc);
540 }
541 
542 static int sp7021_spi_runtime_resume(struct device *dev)
543 {
544 	struct spi_controller *ctlr = dev_get_drvdata(dev);
545 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
546 
547 	return reset_control_deassert(pspim->rstc);
548 }
549 #endif
550 
551 static const struct dev_pm_ops sp7021_spi_pm_ops = {
552 	SET_RUNTIME_PM_OPS(sp7021_spi_runtime_suspend,
553 			   sp7021_spi_runtime_resume, NULL)
554 	SET_SYSTEM_SLEEP_PM_OPS(sp7021_spi_controller_suspend,
555 				sp7021_spi_controller_resume)
556 };
557 
558 static const struct of_device_id sp7021_spi_controller_ids[] = {
559 	{ .compatible = "sunplus,sp7021-spi" },
560 	{}
561 };
562 MODULE_DEVICE_TABLE(of, sp7021_spi_controller_ids);
563 
564 static struct platform_driver sp7021_spi_controller_driver = {
565 	.probe = sp7021_spi_controller_probe,
566 	.remove_new = sp7021_spi_controller_remove,
567 	.driver = {
568 		.name = "sunplus,sp7021-spi-controller",
569 		.of_match_table = sp7021_spi_controller_ids,
570 		.pm     = &sp7021_spi_pm_ops,
571 	},
572 };
573 module_platform_driver(sp7021_spi_controller_driver);
574 
575 MODULE_AUTHOR("Li-hao Kuo <lhjeff911@gmail.com>");
576 MODULE_DESCRIPTION("Sunplus SPI controller driver");
577 MODULE_LICENSE("GPL");
578