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 	// irq spin lock
89 	spinlock_t lock;
90 	// data xfer lock
91 	struct mutex buf_lock;
92 	struct completion isr_done;
93 	struct completion slave_isr;
94 	unsigned int  rx_cur_len;
95 	unsigned int  tx_cur_len;
96 	unsigned int  data_unit;
97 	const u8 *tx_buf;
98 	u8 *rx_buf;
99 };
100 
101 static irqreturn_t sp7021_spi_slave_irq(int irq, void *dev)
102 {
103 	struct sp7021_spi_ctlr *pspim = dev;
104 	unsigned int data_status;
105 
106 	data_status = readl(pspim->s_base + SP7021_DATA_RDY_REG);
107 	data_status |= SP7021_SLAVE_CLR_INT;
108 	writel(data_status , pspim->s_base + SP7021_DATA_RDY_REG);
109 	complete(&pspim->slave_isr);
110 	return IRQ_HANDLED;
111 }
112 
113 static int sp7021_spi_slave_abort(struct spi_controller *ctlr)
114 {
115 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
116 
117 	complete(&pspim->slave_isr);
118 	complete(&pspim->isr_done);
119 	return 0;
120 }
121 
122 static int sp7021_spi_slave_tx(struct spi_device *spi, struct spi_transfer *xfer)
123 {
124 	struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
125 	u32 value;
126 
127 	reinit_completion(&pspim->slave_isr);
128 	value = SP7021_SLAVE_DMA_EN | SP7021_SLAVE_DMA_RW | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
129 	writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
130 	writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
131 	writel(xfer->tx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
132 	value = readl(pspim->s_base + SP7021_DATA_RDY_REG);
133 	value |= SP7021_SLAVE_DATA_RDY;
134 	writel(value, pspim->s_base + SP7021_DATA_RDY_REG);
135 	if (wait_for_completion_interruptible(&pspim->isr_done)) {
136 		dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
137 		return -EINTR;
138 	}
139 	return 0;
140 }
141 
142 static int sp7021_spi_slave_rx(struct spi_device *spi, struct spi_transfer *xfer)
143 {
144 	struct sp7021_spi_ctlr *pspim = spi_controller_get_devdata(spi->controller);
145 	u32 value;
146 
147 	reinit_completion(&pspim->isr_done);
148 	value = SP7021_SLAVE_DMA_EN | FIELD_PREP(SP7021_SLAVE_DMA_CMD, 3);
149 	writel(value, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
150 	writel(xfer->len, pspim->s_base + SP7021_SLAVE_DMA_LENGTH_REG);
151 	writel(xfer->rx_dma, pspim->s_base + SP7021_SLAVE_DMA_ADDR_REG);
152 	if (wait_for_completion_interruptible(&pspim->isr_done)) {
153 		dev_err(&spi->dev, "%s() wait_for_completion err\n", __func__);
154 		return -EINTR;
155 	}
156 	writel(SP7021_SLAVE_SW_RST, pspim->s_base + SP7021_SLAVE_DMA_CTRL_REG);
157 	return 0;
158 }
159 
160 static void sp7021_spi_master_rb(struct sp7021_spi_ctlr *pspim, unsigned int len)
161 {
162 	int i;
163 
164 	for (i = 0; i < len; i++) {
165 		pspim->rx_buf[pspim->rx_cur_len] =
166 			readl(pspim->m_base + SP7021_FIFO_REG);
167 		pspim->rx_cur_len++;
168 	}
169 }
170 
171 static void sp7021_spi_master_wb(struct sp7021_spi_ctlr *pspim, unsigned int len)
172 {
173 	int i;
174 
175 	for (i = 0; i < len; i++) {
176 		writel(pspim->tx_buf[pspim->tx_cur_len],
177 		       pspim->m_base + SP7021_FIFO_REG);
178 		pspim->tx_cur_len++;
179 	}
180 }
181 
182 static irqreturn_t sp7021_spi_master_irq(int irq, void *dev)
183 {
184 	struct sp7021_spi_ctlr *pspim = dev;
185 	unsigned int tx_cnt, total_len;
186 	unsigned int tx_len, rx_cnt;
187 	unsigned int fd_status;
188 	bool isrdone = false;
189 	u32 value;
190 
191 	fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
192 	tx_cnt = FIELD_GET(SP7021_TX_CNT_MASK, fd_status);
193 	tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
194 	total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
195 
196 	if ((fd_status & SP7021_TX_EMP_FLAG) && (fd_status & SP7021_RX_EMP_FLAG) && total_len == 0)
197 		return IRQ_NONE;
198 
199 	if (tx_len == 0 && total_len == 0)
200 		return IRQ_NONE;
201 
202 	spin_lock_irq(&pspim->lock);
203 
204 	rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
205 	if (fd_status & SP7021_RX_FULL_FLAG)
206 		rx_cnt = pspim->data_unit;
207 
208 	tx_cnt = min(tx_len - pspim->tx_cur_len, pspim->data_unit - tx_cnt);
209 	dev_dbg(pspim->dev, "fd_st=0x%x rx_c:%d tx_c:%d tx_l:%d",
210 		fd_status, rx_cnt, tx_cnt, tx_len);
211 
212 	if (rx_cnt > 0)
213 		sp7021_spi_master_rb(pspim, rx_cnt);
214 	if (tx_cnt > 0)
215 		sp7021_spi_master_wb(pspim, tx_cnt);
216 
217 	fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
218 	tx_len = FIELD_GET(SP7021_TX_LEN_MASK, fd_status);
219 	total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
220 
221 	if (fd_status & SP7021_FINISH_FLAG || tx_len == pspim->tx_cur_len) {
222 		while (total_len != pspim->rx_cur_len) {
223 			fd_status = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
224 			total_len = FIELD_GET(SP7021_GET_LEN_MASK, fd_status);
225 			if (fd_status & SP7021_RX_FULL_FLAG)
226 				rx_cnt = pspim->data_unit;
227 			else
228 				rx_cnt = FIELD_GET(SP7021_RX_CNT_MASK, fd_status);
229 
230 			if (rx_cnt > 0)
231 				sp7021_spi_master_rb(pspim, rx_cnt);
232 		}
233 		value = readl(pspim->m_base + SP7021_INT_BUSY_REG);
234 		value |= SP7021_CLR_MASTER_INT;
235 		writel(value, pspim->m_base + SP7021_INT_BUSY_REG);
236 		writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
237 		isrdone = true;
238 	}
239 
240 	if (isrdone)
241 		complete(&pspim->isr_done);
242 	spin_unlock_irq(&pspim->lock);
243 	return IRQ_HANDLED;
244 }
245 
246 static void sp7021_prep_transfer(struct spi_controller *ctlr, struct spi_device *spi)
247 {
248 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
249 
250 	pspim->tx_cur_len = 0;
251 	pspim->rx_cur_len = 0;
252 	pspim->data_unit = SP7021_FIFO_DATA_LEN;
253 }
254 
255 // preliminary set CS, CPOL, CPHA and LSB
256 static int sp7021_spi_controller_prepare_message(struct spi_controller *ctlr,
257 						 struct spi_message *msg)
258 {
259 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
260 	struct spi_device *s = msg->spi;
261 	u32 valus, rs = 0;
262 
263 	valus = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
264 	valus |= SP7021_FD_SW_RST;
265 	writel(valus, pspim->m_base + SP7021_SPI_STATUS_REG);
266 	rs |= SP7021_FD_SEL;
267 	if (s->mode & SPI_CPOL)
268 		rs |= SP7021_CPOL_FD;
269 
270 	if (s->mode & SPI_LSB_FIRST)
271 		rs |= SP7021_LSB_SEL;
272 
273 	if (s->mode & SPI_CS_HIGH)
274 		rs |= SP7021_CS_POR;
275 
276 	if (s->mode & SPI_CPHA)
277 		rs |=  SP7021_CPHA_R;
278 	else
279 		rs |=  SP7021_CPHA_W;
280 
281 	rs |=  FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
282 	pspim->xfer_conf = rs;
283 	if (pspim->xfer_conf & SP7021_CPOL_FD)
284 		writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
285 
286 	return 0;
287 }
288 
289 static void sp7021_spi_setup_clk(struct spi_controller *ctlr, struct spi_transfer *xfer)
290 {
291 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
292 	u32 clk_rate, clk_sel, div;
293 
294 	clk_rate = clk_get_rate(pspim->spi_clk);
295 	div = max(2U, clk_rate / xfer->speed_hz);
296 
297 	clk_sel = (div / 2) - 1;
298 	pspim->xfer_conf &= ~SP7021_CLK_MASK;
299 	pspim->xfer_conf |= FIELD_PREP(SP7021_CLK_MASK, clk_sel);
300 	writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
301 }
302 
303 static int sp7021_spi_master_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
304 				       struct spi_transfer *xfer)
305 {
306 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
307 	unsigned long timeout = msecs_to_jiffies(1000);
308 	unsigned int xfer_cnt, xfer_len, last_len;
309 	unsigned int i, len_temp;
310 	u32 reg_temp;
311 
312 	xfer_cnt = xfer->len / SP7021_SPI_DATA_SIZE;
313 	last_len = xfer->len % SP7021_SPI_DATA_SIZE;
314 
315 	for (i = 0; i <= xfer_cnt; i++) {
316 		mutex_lock(&pspim->buf_lock);
317 		sp7021_prep_transfer(ctlr, spi);
318 		sp7021_spi_setup_clk(ctlr, xfer);
319 		reinit_completion(&pspim->isr_done);
320 
321 		if (i == xfer_cnt)
322 			xfer_len = last_len;
323 		else
324 			xfer_len = SP7021_SPI_DATA_SIZE;
325 
326 		pspim->tx_buf = xfer->tx_buf + i * SP7021_SPI_DATA_SIZE;
327 		pspim->rx_buf = xfer->rx_buf + i * SP7021_SPI_DATA_SIZE;
328 
329 		if (pspim->tx_cur_len < xfer_len) {
330 			len_temp = min(pspim->data_unit, xfer_len);
331 			sp7021_spi_master_wb(pspim, len_temp);
332 		}
333 		reg_temp = readl(pspim->m_base + SP7021_SPI_CONFIG_REG);
334 		reg_temp &= ~SP7021_CLEAN_RW_BYTE;
335 		reg_temp &= ~SP7021_CLEAN_FLUG_MASK;
336 		reg_temp |= SP7021_FD_SEL | SP7021_FINISH_FLAG_MASK |
337 			    SP7021_TX_EMP_FLAG_MASK | SP7021_RX_FULL_FLAG_MASK |
338 			    FIELD_PREP(SP7021_TX_UNIT, 0) | FIELD_PREP(SP7021_RX_UNIT, 0);
339 		writel(reg_temp, pspim->m_base + SP7021_SPI_CONFIG_REG);
340 
341 		reg_temp = FIELD_PREP(SP7021_SET_TX_LEN, xfer_len) |
342 				      FIELD_PREP(SP7021_SET_XFER_LEN, xfer_len) |
343 				      SP7021_SPI_START_FD;
344 		writel(reg_temp, pspim->m_base + SP7021_SPI_STATUS_REG);
345 
346 		if (!wait_for_completion_interruptible_timeout(&pspim->isr_done, timeout)) {
347 			dev_err(&spi->dev, "wait_for_completion err\n");
348 			mutex_unlock(&pspim->buf_lock);
349 			return -ETIMEDOUT;
350 		}
351 
352 		reg_temp = readl(pspim->m_base + SP7021_SPI_STATUS_REG);
353 		if (reg_temp & SP7021_FINISH_FLAG) {
354 			writel(SP7021_FINISH_FLAG, pspim->m_base + SP7021_SPI_STATUS_REG);
355 			writel(readl(pspim->m_base + SP7021_SPI_CONFIG_REG) &
356 				SP7021_CLEAN_FLUG_MASK, pspim->m_base + SP7021_SPI_CONFIG_REG);
357 		}
358 
359 		if (pspim->xfer_conf & SP7021_CPOL_FD)
360 			writel(pspim->xfer_conf, pspim->m_base + SP7021_SPI_CONFIG_REG);
361 
362 		mutex_unlock(&pspim->buf_lock);
363 	}
364 	return 0;
365 }
366 
367 static int sp7021_spi_slave_transfer_one(struct spi_controller *ctlr, struct spi_device *spi,
368 				       struct spi_transfer *xfer)
369 {
370 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
371 	struct device *dev = pspim->dev;
372 	int ret;
373 
374 	if (xfer->tx_buf && !xfer->rx_buf) {
375 		xfer->tx_dma = dma_map_single(dev, (void *)xfer->tx_buf,
376 					      xfer->len, DMA_TO_DEVICE);
377 		if (dma_mapping_error(dev, xfer->tx_dma))
378 			return -ENOMEM;
379 		ret = sp7021_spi_slave_tx(spi, xfer);
380 		dma_unmap_single(dev, xfer->tx_dma, xfer->len, DMA_TO_DEVICE);
381 	} else if (xfer->rx_buf && !xfer->tx_buf) {
382 		xfer->rx_dma = dma_map_single(dev, xfer->rx_buf, xfer->len,
383 					      DMA_FROM_DEVICE);
384 		if (dma_mapping_error(dev, xfer->rx_dma))
385 			return -ENOMEM;
386 		ret = sp7021_spi_slave_rx(spi, xfer);
387 		dma_unmap_single(dev, xfer->rx_dma, xfer->len, DMA_FROM_DEVICE);
388 	} else {
389 		dev_dbg(&ctlr->dev, "%s() wrong command\n", __func__);
390 		return -EINVAL;
391 	}
392 
393 	spi_finalize_current_transfer(ctlr);
394 	return ret;
395 }
396 
397 static void sp7021_spi_disable_unprepare(void *data)
398 {
399 	clk_disable_unprepare(data);
400 }
401 
402 static void sp7021_spi_reset_control_assert(void *data)
403 {
404 	reset_control_assert(data);
405 }
406 
407 static int sp7021_spi_controller_probe(struct platform_device *pdev)
408 {
409 	struct device *dev = &pdev->dev;
410 	struct sp7021_spi_ctlr *pspim;
411 	struct spi_controller *ctlr;
412 	int mode, ret;
413 
414 	pdev->id = of_alias_get_id(pdev->dev.of_node, "sp_spi");
415 
416 	if (device_property_read_bool(dev, "spi-slave"))
417 		mode = SP7021_SLAVE_MODE;
418 	else
419 		mode = SP7021_MASTER_MODE;
420 
421 	if (mode == SP7021_SLAVE_MODE)
422 		ctlr = devm_spi_alloc_slave(dev, sizeof(*pspim));
423 	else
424 		ctlr = devm_spi_alloc_master(dev, sizeof(*pspim));
425 	if (!ctlr)
426 		return -ENOMEM;
427 	device_set_node(&ctlr->dev, dev_fwnode(dev));
428 	ctlr->bus_num = pdev->id;
429 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST;
430 	ctlr->auto_runtime_pm = true;
431 	ctlr->prepare_message = sp7021_spi_controller_prepare_message;
432 	if (mode == SP7021_SLAVE_MODE) {
433 		ctlr->transfer_one = sp7021_spi_slave_transfer_one;
434 		ctlr->slave_abort = sp7021_spi_slave_abort;
435 		ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
436 	} else {
437 		ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
438 		ctlr->min_speed_hz = 40000;
439 		ctlr->max_speed_hz = 25000000;
440 		ctlr->use_gpio_descriptors = true;
441 		ctlr->flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX;
442 		ctlr->transfer_one = sp7021_spi_master_transfer_one;
443 	}
444 	platform_set_drvdata(pdev, ctlr);
445 	pspim = spi_controller_get_devdata(ctlr);
446 	pspim->mode = mode;
447 	pspim->ctlr = ctlr;
448 	pspim->dev = dev;
449 	spin_lock_init(&pspim->lock);
450 	mutex_init(&pspim->buf_lock);
451 	init_completion(&pspim->isr_done);
452 	init_completion(&pspim->slave_isr);
453 
454 	pspim->m_base = devm_platform_ioremap_resource_byname(pdev, "master");
455 	if (IS_ERR(pspim->m_base))
456 		return dev_err_probe(dev, PTR_ERR(pspim->m_base), "m_base get fail\n");
457 
458 	pspim->s_base = devm_platform_ioremap_resource_byname(pdev, "slave");
459 	if (IS_ERR(pspim->s_base))
460 		return dev_err_probe(dev, PTR_ERR(pspim->s_base), "s_base get fail\n");
461 
462 	pspim->m_irq = platform_get_irq_byname(pdev, "master_risc");
463 	if (pspim->m_irq < 0)
464 		return pspim->m_irq;
465 
466 	pspim->s_irq = platform_get_irq_byname(pdev, "slave_risc");
467 	if (pspim->s_irq < 0)
468 		return pspim->s_irq;
469 
470 	pspim->spi_clk = devm_clk_get(dev, NULL);
471 	if (IS_ERR(pspim->spi_clk))
472 		return dev_err_probe(dev, PTR_ERR(pspim->spi_clk), "clk get fail\n");
473 
474 	pspim->rstc = devm_reset_control_get_exclusive(dev, NULL);
475 	if (IS_ERR(pspim->rstc))
476 		return dev_err_probe(dev, PTR_ERR(pspim->rstc), "rst get fail\n");
477 
478 	ret = clk_prepare_enable(pspim->spi_clk);
479 	if (ret)
480 		return dev_err_probe(dev, ret, "failed to enable clk\n");
481 
482 	ret = devm_add_action_or_reset(dev, sp7021_spi_disable_unprepare, pspim->spi_clk);
483 	if (ret)
484 		return ret;
485 
486 	ret = reset_control_deassert(pspim->rstc);
487 	if (ret)
488 		return dev_err_probe(dev, ret, "failed to deassert reset\n");
489 
490 	ret = devm_add_action_or_reset(dev, sp7021_spi_reset_control_assert, pspim->rstc);
491 	if (ret)
492 		return ret;
493 
494 	ret = devm_request_irq(dev, pspim->m_irq, sp7021_spi_master_irq,
495 			       IRQF_TRIGGER_RISING, pdev->name, pspim);
496 	if (ret)
497 		return ret;
498 
499 	ret = devm_request_irq(dev, pspim->s_irq, sp7021_spi_slave_irq,
500 			       IRQF_TRIGGER_RISING, pdev->name, pspim);
501 	if (ret)
502 		return ret;
503 
504 	pm_runtime_enable(dev);
505 	ret = spi_register_controller(ctlr);
506 	if (ret) {
507 		pm_runtime_disable(dev);
508 		return dev_err_probe(dev, ret, "spi_register_master fail\n");
509 	}
510 	return 0;
511 }
512 
513 static int sp7021_spi_controller_remove(struct platform_device *pdev)
514 {
515 	struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
516 
517 	spi_unregister_controller(ctlr);
518 	pm_runtime_disable(&pdev->dev);
519 	pm_runtime_set_suspended(&pdev->dev);
520 	return 0;
521 }
522 
523 static int __maybe_unused sp7021_spi_controller_suspend(struct device *dev)
524 {
525 	struct spi_controller *ctlr = dev_get_drvdata(dev);
526 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
527 
528 	return reset_control_assert(pspim->rstc);
529 }
530 
531 static int __maybe_unused sp7021_spi_controller_resume(struct device *dev)
532 {
533 	struct spi_controller *ctlr = dev_get_drvdata(dev);
534 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
535 
536 	reset_control_deassert(pspim->rstc);
537 	return clk_prepare_enable(pspim->spi_clk);
538 }
539 
540 #ifdef CONFIG_PM
541 static int sp7021_spi_runtime_suspend(struct device *dev)
542 {
543 	struct spi_controller *ctlr = dev_get_drvdata(dev);
544 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
545 
546 	return reset_control_assert(pspim->rstc);
547 }
548 
549 static int sp7021_spi_runtime_resume(struct device *dev)
550 {
551 	struct spi_controller *ctlr = dev_get_drvdata(dev);
552 	struct sp7021_spi_ctlr *pspim = spi_master_get_devdata(ctlr);
553 
554 	return reset_control_deassert(pspim->rstc);
555 }
556 #endif
557 
558 static const struct dev_pm_ops sp7021_spi_pm_ops = {
559 	SET_RUNTIME_PM_OPS(sp7021_spi_runtime_suspend,
560 			   sp7021_spi_runtime_resume, NULL)
561 	SET_SYSTEM_SLEEP_PM_OPS(sp7021_spi_controller_suspend,
562 				sp7021_spi_controller_resume)
563 };
564 
565 static const struct of_device_id sp7021_spi_controller_ids[] = {
566 	{ .compatible = "sunplus,sp7021-spi" },
567 	{}
568 };
569 MODULE_DEVICE_TABLE(of, sp7021_spi_controller_ids);
570 
571 static struct platform_driver sp7021_spi_controller_driver = {
572 	.probe = sp7021_spi_controller_probe,
573 	.remove = sp7021_spi_controller_remove,
574 	.driver = {
575 		.name = "sunplus,sp7021-spi-controller",
576 		.of_match_table = sp7021_spi_controller_ids,
577 		.pm     = &sp7021_spi_pm_ops,
578 	},
579 };
580 module_platform_driver(sp7021_spi_controller_driver);
581 
582 MODULE_AUTHOR("Li-hao Kuo <lhjeff911@gmail.com>");
583 MODULE_DESCRIPTION("Sunplus SPI controller driver");
584 MODULE_LICENSE("GPL");
585