xref: /openbmc/linux/drivers/i2c/busses/i2c-sprd.c (revision 59b4412f)
1 /*
2  * Copyright (C) 2017 Spreadtrum Communications Inc.
3  *
4  * SPDX-License-Identifier: (GPL-2.0+ OR MIT)
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/delay.h>
9 #include <linux/err.h>
10 #include <linux/io.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_runtime.h>
20 
21 #define I2C_CTL			0x00
22 #define I2C_ADDR_CFG		0x04
23 #define I2C_COUNT		0x08
24 #define I2C_RX			0x0c
25 #define I2C_TX			0x10
26 #define I2C_STATUS		0x14
27 #define I2C_HSMODE_CFG		0x18
28 #define I2C_VERSION		0x1c
29 #define ADDR_DVD0		0x20
30 #define ADDR_DVD1		0x24
31 #define ADDR_STA0_DVD		0x28
32 #define ADDR_RST		0x2c
33 
34 /* I2C_CTL */
35 #define STP_EN			BIT(20)
36 #define FIFO_AF_LVL_MASK	GENMASK(19, 16)
37 #define FIFO_AF_LVL		16
38 #define FIFO_AE_LVL_MASK	GENMASK(15, 12)
39 #define FIFO_AE_LVL		12
40 #define I2C_DMA_EN		BIT(11)
41 #define FULL_INTEN		BIT(10)
42 #define EMPTY_INTEN		BIT(9)
43 #define I2C_DVD_OPT		BIT(8)
44 #define I2C_OUT_OPT		BIT(7)
45 #define I2C_TRIM_OPT		BIT(6)
46 #define I2C_HS_MODE		BIT(4)
47 #define I2C_MODE		BIT(3)
48 #define I2C_EN			BIT(2)
49 #define I2C_INT_EN		BIT(1)
50 #define I2C_START		BIT(0)
51 
52 /* I2C_STATUS */
53 #define SDA_IN			BIT(21)
54 #define SCL_IN			BIT(20)
55 #define FIFO_FULL		BIT(4)
56 #define FIFO_EMPTY		BIT(3)
57 #define I2C_INT			BIT(2)
58 #define I2C_RX_ACK		BIT(1)
59 #define I2C_BUSY		BIT(0)
60 
61 /* ADDR_RST */
62 #define I2C_RST			BIT(0)
63 
64 #define I2C_FIFO_DEEP		12
65 #define I2C_FIFO_FULL_THLD	15
66 #define I2C_FIFO_EMPTY_THLD	4
67 #define I2C_DATA_STEP		8
68 #define I2C_ADDR_DVD0_CALC(high, low)	\
69 	((((high) & GENMASK(15, 0)) << 16) | ((low) & GENMASK(15, 0)))
70 #define I2C_ADDR_DVD1_CALC(high, low)	\
71 	(((high) & GENMASK(31, 16)) | (((low) & GENMASK(31, 16)) >> 16))
72 
73 /* timeout (ms) for pm runtime autosuspend */
74 #define SPRD_I2C_PM_TIMEOUT	1000
75 
76 /* SPRD i2c data structure */
77 struct sprd_i2c {
78 	struct i2c_adapter adap;
79 	struct device *dev;
80 	void __iomem *base;
81 	struct i2c_msg *msg;
82 	struct clk *clk;
83 	u32 src_clk;
84 	u32 bus_freq;
85 	struct completion complete;
86 	u8 *buf;
87 	u32 count;
88 	int irq;
89 	int err;
90 };
91 
92 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
93 {
94 	writel(count, i2c_dev->base + I2C_COUNT);
95 }
96 
97 static void sprd_i2c_send_stop(struct sprd_i2c *i2c_dev, int stop)
98 {
99 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
100 
101 	if (stop)
102 		writel(tmp & ~STP_EN, i2c_dev->base + I2C_CTL);
103 	else
104 		writel(tmp | STP_EN, i2c_dev->base + I2C_CTL);
105 }
106 
107 static void sprd_i2c_clear_start(struct sprd_i2c *i2c_dev)
108 {
109 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
110 
111 	writel(tmp & ~I2C_START, i2c_dev->base + I2C_CTL);
112 }
113 
114 static void sprd_i2c_clear_ack(struct sprd_i2c *i2c_dev)
115 {
116 	u32 tmp = readl(i2c_dev->base + I2C_STATUS);
117 
118 	writel(tmp & ~I2C_RX_ACK, i2c_dev->base + I2C_STATUS);
119 }
120 
121 static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev)
122 {
123 	u32 tmp = readl(i2c_dev->base + I2C_STATUS);
124 
125 	writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS);
126 }
127 
128 static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev)
129 {
130 	writel(I2C_RST, i2c_dev->base + ADDR_RST);
131 }
132 
133 static void sprd_i2c_set_devaddr(struct sprd_i2c *i2c_dev, struct i2c_msg *m)
134 {
135 	writel(m->addr << 1, i2c_dev->base + I2C_ADDR_CFG);
136 }
137 
138 static void sprd_i2c_write_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len)
139 {
140 	u32 i;
141 
142 	for (i = 0; i < len; i++)
143 		writeb(buf[i], i2c_dev->base + I2C_TX);
144 }
145 
146 static void sprd_i2c_read_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len)
147 {
148 	u32 i;
149 
150 	for (i = 0; i < len; i++)
151 		buf[i] = readb(i2c_dev->base + I2C_RX);
152 }
153 
154 static void sprd_i2c_set_full_thld(struct sprd_i2c *i2c_dev, u32 full_thld)
155 {
156 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
157 
158 	tmp &= ~FIFO_AF_LVL_MASK;
159 	tmp |= full_thld << FIFO_AF_LVL;
160 	writel(tmp, i2c_dev->base + I2C_CTL);
161 };
162 
163 static void sprd_i2c_set_empty_thld(struct sprd_i2c *i2c_dev, u32 empty_thld)
164 {
165 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
166 
167 	tmp &= ~FIFO_AE_LVL_MASK;
168 	tmp |= empty_thld << FIFO_AE_LVL;
169 	writel(tmp, i2c_dev->base + I2C_CTL);
170 };
171 
172 static void sprd_i2c_set_fifo_full_int(struct sprd_i2c *i2c_dev, int enable)
173 {
174 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
175 
176 	if (enable)
177 		tmp |= FULL_INTEN;
178 	else
179 		tmp &= ~FULL_INTEN;
180 
181 	writel(tmp, i2c_dev->base + I2C_CTL);
182 };
183 
184 static void sprd_i2c_set_fifo_empty_int(struct sprd_i2c *i2c_dev, int enable)
185 {
186 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
187 
188 	if (enable)
189 		tmp |= EMPTY_INTEN;
190 	else
191 		tmp &= ~EMPTY_INTEN;
192 
193 	writel(tmp, i2c_dev->base + I2C_CTL);
194 };
195 
196 static void sprd_i2c_opt_start(struct sprd_i2c *i2c_dev)
197 {
198 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
199 
200 	writel(tmp | I2C_START, i2c_dev->base + I2C_CTL);
201 }
202 
203 static void sprd_i2c_opt_mode(struct sprd_i2c *i2c_dev, int rw)
204 {
205 	u32 cmd = readl(i2c_dev->base + I2C_CTL) & ~I2C_MODE;
206 
207 	writel(cmd | rw << 3, i2c_dev->base + I2C_CTL);
208 }
209 
210 static void sprd_i2c_data_transfer(struct sprd_i2c *i2c_dev)
211 {
212 	u32 i2c_count = i2c_dev->count;
213 	u32 need_tran = i2c_count <= I2C_FIFO_DEEP ? i2c_count : I2C_FIFO_DEEP;
214 	struct i2c_msg *msg = i2c_dev->msg;
215 
216 	if (msg->flags & I2C_M_RD) {
217 		sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, I2C_FIFO_FULL_THLD);
218 		i2c_dev->count -= I2C_FIFO_FULL_THLD;
219 		i2c_dev->buf += I2C_FIFO_FULL_THLD;
220 
221 		/*
222 		 * If the read data count is larger than rx fifo full threshold,
223 		 * we should enable the rx fifo full interrupt to read data
224 		 * again.
225 		 */
226 		if (i2c_dev->count >= I2C_FIFO_FULL_THLD)
227 			sprd_i2c_set_fifo_full_int(i2c_dev, 1);
228 	} else {
229 		sprd_i2c_write_bytes(i2c_dev, i2c_dev->buf, need_tran);
230 		i2c_dev->buf += need_tran;
231 		i2c_dev->count -= need_tran;
232 
233 		/*
234 		 * If the write data count is arger than tx fifo depth which
235 		 * means we can not write all data in one time, then we should
236 		 * enable the tx fifo empty interrupt to write again.
237 		 */
238 		if (i2c_count > I2C_FIFO_DEEP)
239 			sprd_i2c_set_fifo_empty_int(i2c_dev, 1);
240 	}
241 }
242 
243 static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap,
244 			       struct i2c_msg *msg, bool is_last_msg)
245 {
246 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
247 
248 	i2c_dev->msg = msg;
249 	i2c_dev->buf = msg->buf;
250 	i2c_dev->count = msg->len;
251 
252 	reinit_completion(&i2c_dev->complete);
253 	sprd_i2c_reset_fifo(i2c_dev);
254 	sprd_i2c_set_devaddr(i2c_dev, msg);
255 	sprd_i2c_set_count(i2c_dev, msg->len);
256 
257 	if (msg->flags & I2C_M_RD) {
258 		sprd_i2c_opt_mode(i2c_dev, 1);
259 		sprd_i2c_send_stop(i2c_dev, 1);
260 	} else {
261 		sprd_i2c_opt_mode(i2c_dev, 0);
262 		sprd_i2c_send_stop(i2c_dev, !!is_last_msg);
263 	}
264 
265 	/*
266 	 * We should enable rx fifo full interrupt to get data when receiving
267 	 * full data.
268 	 */
269 	if (msg->flags & I2C_M_RD)
270 		sprd_i2c_set_fifo_full_int(i2c_dev, 1);
271 	else
272 		sprd_i2c_data_transfer(i2c_dev);
273 
274 	sprd_i2c_opt_start(i2c_dev);
275 
276 	wait_for_completion(&i2c_dev->complete);
277 
278 	return i2c_dev->err;
279 }
280 
281 static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap,
282 				struct i2c_msg *msgs, int num)
283 {
284 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
285 	int im, ret;
286 
287 	ret = pm_runtime_get_sync(i2c_dev->dev);
288 	if (ret < 0)
289 		return ret;
290 
291 	for (im = 0; im < num - 1; im++) {
292 		ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0);
293 		if (ret)
294 			goto err_msg;
295 	}
296 
297 	ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im++], 1);
298 
299 err_msg:
300 	pm_runtime_mark_last_busy(i2c_dev->dev);
301 	pm_runtime_put_autosuspend(i2c_dev->dev);
302 
303 	return ret < 0 ? ret : im;
304 }
305 
306 static u32 sprd_i2c_func(struct i2c_adapter *adap)
307 {
308 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
309 }
310 
311 static const struct i2c_algorithm sprd_i2c_algo = {
312 	.master_xfer = sprd_i2c_master_xfer,
313 	.functionality = sprd_i2c_func,
314 };
315 
316 static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq)
317 {
318 	u32 apb_clk = i2c_dev->src_clk;
319 	/*
320 	 * From I2C databook, the prescale calculation formula:
321 	 * prescale = freq_i2c / (4 * freq_scl) - 1;
322 	 */
323 	u32 i2c_dvd = apb_clk / (4 * freq) - 1;
324 	/*
325 	 * From I2C databook, the high period of SCL clock is recommended as
326 	 * 40% (2/5), and the low period of SCL clock is recommended as 60%
327 	 * (3/5), then the formula should be:
328 	 * high = (prescale * 2 * 2) / 5
329 	 * low = (prescale * 2 * 3) / 5
330 	 */
331 	u32 high = ((i2c_dvd << 1) * 2) / 5;
332 	u32 low = ((i2c_dvd << 1) * 3) / 5;
333 	u32 div0 = I2C_ADDR_DVD0_CALC(high, low);
334 	u32 div1 = I2C_ADDR_DVD1_CALC(high, low);
335 
336 	writel(div0, i2c_dev->base + ADDR_DVD0);
337 	writel(div1, i2c_dev->base + ADDR_DVD1);
338 
339 	/* Start hold timing = hold time(us) * source clock */
340 	if (freq == I2C_MAX_FAST_MODE_FREQ)
341 		writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD);
342 	else if (freq == I2C_MAX_STANDARD_MODE_FREQ)
343 		writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD);
344 }
345 
346 static void sprd_i2c_enable(struct sprd_i2c *i2c_dev)
347 {
348 	u32 tmp = I2C_DVD_OPT;
349 
350 	writel(tmp, i2c_dev->base + I2C_CTL);
351 
352 	sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD);
353 	sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD);
354 
355 	sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq);
356 	sprd_i2c_reset_fifo(i2c_dev);
357 	sprd_i2c_clear_irq(i2c_dev);
358 
359 	tmp = readl(i2c_dev->base + I2C_CTL);
360 	writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL);
361 }
362 
363 static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id)
364 {
365 	struct sprd_i2c *i2c_dev = dev_id;
366 	struct i2c_msg *msg = i2c_dev->msg;
367 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
368 	u32 i2c_tran;
369 
370 	if (msg->flags & I2C_M_RD)
371 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
372 	else
373 		i2c_tran = i2c_dev->count;
374 
375 	/*
376 	 * If we got one ACK from slave when writing data, and we did not
377 	 * finish this transmission (i2c_tran is not zero), then we should
378 	 * continue to write data.
379 	 *
380 	 * For reading data, ack is always true, if i2c_tran is not 0 which
381 	 * means we still need to contine to read data from slave.
382 	 */
383 	if (i2c_tran && ack) {
384 		sprd_i2c_data_transfer(i2c_dev);
385 		return IRQ_HANDLED;
386 	}
387 
388 	i2c_dev->err = 0;
389 
390 	/*
391 	 * If we did not get one ACK from slave when writing data, we should
392 	 * return -EIO to notify users.
393 	 */
394 	if (!ack)
395 		i2c_dev->err = -EIO;
396 	else if (msg->flags & I2C_M_RD && i2c_dev->count)
397 		sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, i2c_dev->count);
398 
399 	/* Transmission is done and clear ack and start operation */
400 	sprd_i2c_clear_ack(i2c_dev);
401 	sprd_i2c_clear_start(i2c_dev);
402 	complete(&i2c_dev->complete);
403 
404 	return IRQ_HANDLED;
405 }
406 
407 static irqreturn_t sprd_i2c_isr(int irq, void *dev_id)
408 {
409 	struct sprd_i2c *i2c_dev = dev_id;
410 	struct i2c_msg *msg = i2c_dev->msg;
411 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
412 	u32 i2c_tran;
413 
414 	if (msg->flags & I2C_M_RD)
415 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
416 	else
417 		i2c_tran = i2c_dev->count;
418 
419 	/*
420 	 * If we did not get one ACK from slave when writing data, then we
421 	 * should finish this transmission since we got some errors.
422 	 *
423 	 * When writing data, if i2c_tran == 0 which means we have writen
424 	 * done all data, then we can finish this transmission.
425 	 *
426 	 * When reading data, if conut < rx fifo full threshold, which
427 	 * means we can read all data in one time, then we can finish this
428 	 * transmission too.
429 	 */
430 	if (!i2c_tran || !ack) {
431 		sprd_i2c_clear_start(i2c_dev);
432 		sprd_i2c_clear_irq(i2c_dev);
433 	}
434 
435 	sprd_i2c_set_fifo_empty_int(i2c_dev, 0);
436 	sprd_i2c_set_fifo_full_int(i2c_dev, 0);
437 
438 	return IRQ_WAKE_THREAD;
439 }
440 
441 static int sprd_i2c_clk_init(struct sprd_i2c *i2c_dev)
442 {
443 	struct clk *clk_i2c, *clk_parent;
444 
445 	clk_i2c = devm_clk_get(i2c_dev->dev, "i2c");
446 	if (IS_ERR(clk_i2c)) {
447 		dev_warn(i2c_dev->dev, "i2c%d can't get the i2c clock\n",
448 			 i2c_dev->adap.nr);
449 		clk_i2c = NULL;
450 	}
451 
452 	clk_parent = devm_clk_get(i2c_dev->dev, "source");
453 	if (IS_ERR(clk_parent)) {
454 		dev_warn(i2c_dev->dev, "i2c%d can't get the source clock\n",
455 			 i2c_dev->adap.nr);
456 		clk_parent = NULL;
457 	}
458 
459 	if (clk_set_parent(clk_i2c, clk_parent))
460 		i2c_dev->src_clk = clk_get_rate(clk_i2c);
461 	else
462 		i2c_dev->src_clk = 26000000;
463 
464 	dev_dbg(i2c_dev->dev, "i2c%d set source clock is %d\n",
465 		i2c_dev->adap.nr, i2c_dev->src_clk);
466 
467 	i2c_dev->clk = devm_clk_get(i2c_dev->dev, "enable");
468 	if (IS_ERR(i2c_dev->clk)) {
469 		dev_err(i2c_dev->dev, "i2c%d can't get the enable clock\n",
470 			i2c_dev->adap.nr);
471 		return PTR_ERR(i2c_dev->clk);
472 	}
473 
474 	return 0;
475 }
476 
477 static int sprd_i2c_probe(struct platform_device *pdev)
478 {
479 	struct device *dev = &pdev->dev;
480 	struct sprd_i2c *i2c_dev;
481 	u32 prop;
482 	int ret;
483 
484 	pdev->id = of_alias_get_id(dev->of_node, "i2c");
485 
486 	i2c_dev = devm_kzalloc(dev, sizeof(struct sprd_i2c), GFP_KERNEL);
487 	if (!i2c_dev)
488 		return -ENOMEM;
489 
490 	i2c_dev->base = devm_platform_ioremap_resource(pdev, 0);
491 	if (IS_ERR(i2c_dev->base))
492 		return PTR_ERR(i2c_dev->base);
493 
494 	i2c_dev->irq = platform_get_irq(pdev, 0);
495 	if (i2c_dev->irq < 0)
496 		return i2c_dev->irq;
497 
498 	i2c_set_adapdata(&i2c_dev->adap, i2c_dev);
499 	init_completion(&i2c_dev->complete);
500 	snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name),
501 		 "%s", "sprd-i2c");
502 
503 	i2c_dev->bus_freq = I2C_MAX_STANDARD_MODE_FREQ;
504 	i2c_dev->adap.owner = THIS_MODULE;
505 	i2c_dev->dev = dev;
506 	i2c_dev->adap.retries = 3;
507 	i2c_dev->adap.algo = &sprd_i2c_algo;
508 	i2c_dev->adap.algo_data = i2c_dev;
509 	i2c_dev->adap.dev.parent = dev;
510 	i2c_dev->adap.nr = pdev->id;
511 	i2c_dev->adap.dev.of_node = dev->of_node;
512 
513 	if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop))
514 		i2c_dev->bus_freq = prop;
515 
516 	/* We only support 100k and 400k now, otherwise will return error. */
517 	if (i2c_dev->bus_freq != I2C_MAX_STANDARD_MODE_FREQ &&
518 	    i2c_dev->bus_freq != I2C_MAX_FAST_MODE_FREQ)
519 		return -EINVAL;
520 
521 	ret = sprd_i2c_clk_init(i2c_dev);
522 	if (ret)
523 		return ret;
524 
525 	platform_set_drvdata(pdev, i2c_dev);
526 
527 	ret = clk_prepare_enable(i2c_dev->clk);
528 	if (ret)
529 		return ret;
530 
531 	sprd_i2c_enable(i2c_dev);
532 
533 	pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT);
534 	pm_runtime_use_autosuspend(i2c_dev->dev);
535 	pm_runtime_set_active(i2c_dev->dev);
536 	pm_runtime_enable(i2c_dev->dev);
537 
538 	ret = pm_runtime_get_sync(i2c_dev->dev);
539 	if (ret < 0)
540 		goto err_rpm_put;
541 
542 	ret = devm_request_threaded_irq(dev, i2c_dev->irq,
543 		sprd_i2c_isr, sprd_i2c_isr_thread,
544 		IRQF_NO_SUSPEND | IRQF_ONESHOT,
545 		pdev->name, i2c_dev);
546 	if (ret) {
547 		dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq);
548 		goto err_rpm_put;
549 	}
550 
551 	ret = i2c_add_numbered_adapter(&i2c_dev->adap);
552 	if (ret) {
553 		dev_err(&pdev->dev, "add adapter failed\n");
554 		goto err_rpm_put;
555 	}
556 
557 	pm_runtime_mark_last_busy(i2c_dev->dev);
558 	pm_runtime_put_autosuspend(i2c_dev->dev);
559 	return 0;
560 
561 err_rpm_put:
562 	pm_runtime_put_noidle(i2c_dev->dev);
563 	pm_runtime_disable(i2c_dev->dev);
564 	clk_disable_unprepare(i2c_dev->clk);
565 	return ret;
566 }
567 
568 static int sprd_i2c_remove(struct platform_device *pdev)
569 {
570 	struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev);
571 	int ret;
572 
573 	ret = pm_runtime_get_sync(i2c_dev->dev);
574 	if (ret < 0)
575 		return ret;
576 
577 	i2c_del_adapter(&i2c_dev->adap);
578 	clk_disable_unprepare(i2c_dev->clk);
579 
580 	pm_runtime_put_noidle(i2c_dev->dev);
581 	pm_runtime_disable(i2c_dev->dev);
582 
583 	return 0;
584 }
585 
586 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *dev)
587 {
588 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
589 
590 	i2c_mark_adapter_suspended(&i2c_dev->adap);
591 	return pm_runtime_force_suspend(dev);
592 }
593 
594 static int __maybe_unused sprd_i2c_resume_noirq(struct device *dev)
595 {
596 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
597 
598 	i2c_mark_adapter_resumed(&i2c_dev->adap);
599 	return pm_runtime_force_resume(dev);
600 }
601 
602 static int __maybe_unused sprd_i2c_runtime_suspend(struct device *dev)
603 {
604 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
605 
606 	clk_disable_unprepare(i2c_dev->clk);
607 
608 	return 0;
609 }
610 
611 static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev)
612 {
613 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
614 	int ret;
615 
616 	ret = clk_prepare_enable(i2c_dev->clk);
617 	if (ret)
618 		return ret;
619 
620 	sprd_i2c_enable(i2c_dev);
621 
622 	return 0;
623 }
624 
625 static const struct dev_pm_ops sprd_i2c_pm_ops = {
626 	SET_RUNTIME_PM_OPS(sprd_i2c_runtime_suspend,
627 			   sprd_i2c_runtime_resume, NULL)
628 
629 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sprd_i2c_suspend_noirq,
630 				      sprd_i2c_resume_noirq)
631 };
632 
633 static const struct of_device_id sprd_i2c_of_match[] = {
634 	{ .compatible = "sprd,sc9860-i2c", },
635 	{},
636 };
637 
638 static struct platform_driver sprd_i2c_driver = {
639 	.probe = sprd_i2c_probe,
640 	.remove = sprd_i2c_remove,
641 	.driver = {
642 		   .name = "sprd-i2c",
643 		   .of_match_table = sprd_i2c_of_match,
644 		   .pm = &sprd_i2c_pm_ops,
645 	},
646 };
647 
648 module_platform_driver(sprd_i2c_driver);
649 
650 MODULE_DESCRIPTION("Spreadtrum I2C master controller driver");
651 MODULE_LICENSE("GPL v2");
652