xref: /openbmc/linux/drivers/i2c/busses/i2c-sprd.c (revision c1cf3d89)
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 /* timeout (ms) for transfer message */
76 #define I2C_XFER_TIMEOUT	1000
77 
78 /* SPRD i2c data structure */
79 struct sprd_i2c {
80 	struct i2c_adapter adap;
81 	struct device *dev;
82 	void __iomem *base;
83 	struct i2c_msg *msg;
84 	struct clk *clk;
85 	u32 src_clk;
86 	u32 bus_freq;
87 	struct completion complete;
88 	u8 *buf;
89 	u32 count;
90 	int irq;
91 	int err;
92 };
93 
94 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
95 {
96 	writel(count, i2c_dev->base + I2C_COUNT);
97 }
98 
99 static void sprd_i2c_send_stop(struct sprd_i2c *i2c_dev, int stop)
100 {
101 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
102 
103 	if (stop)
104 		writel(tmp & ~STP_EN, i2c_dev->base + I2C_CTL);
105 	else
106 		writel(tmp | STP_EN, i2c_dev->base + I2C_CTL);
107 }
108 
109 static void sprd_i2c_clear_start(struct sprd_i2c *i2c_dev)
110 {
111 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
112 
113 	writel(tmp & ~I2C_START, i2c_dev->base + I2C_CTL);
114 }
115 
116 static void sprd_i2c_clear_ack(struct sprd_i2c *i2c_dev)
117 {
118 	u32 tmp = readl(i2c_dev->base + I2C_STATUS);
119 
120 	writel(tmp & ~I2C_RX_ACK, i2c_dev->base + I2C_STATUS);
121 }
122 
123 static void sprd_i2c_clear_irq(struct sprd_i2c *i2c_dev)
124 {
125 	u32 tmp = readl(i2c_dev->base + I2C_STATUS);
126 
127 	writel(tmp & ~I2C_INT, i2c_dev->base + I2C_STATUS);
128 }
129 
130 static void sprd_i2c_reset_fifo(struct sprd_i2c *i2c_dev)
131 {
132 	writel(I2C_RST, i2c_dev->base + ADDR_RST);
133 }
134 
135 static void sprd_i2c_set_devaddr(struct sprd_i2c *i2c_dev, struct i2c_msg *m)
136 {
137 	writel(m->addr << 1, i2c_dev->base + I2C_ADDR_CFG);
138 }
139 
140 static void sprd_i2c_write_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len)
141 {
142 	u32 i;
143 
144 	for (i = 0; i < len; i++)
145 		writeb(buf[i], i2c_dev->base + I2C_TX);
146 }
147 
148 static void sprd_i2c_read_bytes(struct sprd_i2c *i2c_dev, u8 *buf, u32 len)
149 {
150 	u32 i;
151 
152 	for (i = 0; i < len; i++)
153 		buf[i] = readb(i2c_dev->base + I2C_RX);
154 }
155 
156 static void sprd_i2c_set_full_thld(struct sprd_i2c *i2c_dev, u32 full_thld)
157 {
158 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
159 
160 	tmp &= ~FIFO_AF_LVL_MASK;
161 	tmp |= full_thld << FIFO_AF_LVL;
162 	writel(tmp, i2c_dev->base + I2C_CTL);
163 };
164 
165 static void sprd_i2c_set_empty_thld(struct sprd_i2c *i2c_dev, u32 empty_thld)
166 {
167 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
168 
169 	tmp &= ~FIFO_AE_LVL_MASK;
170 	tmp |= empty_thld << FIFO_AE_LVL;
171 	writel(tmp, i2c_dev->base + I2C_CTL);
172 };
173 
174 static void sprd_i2c_set_fifo_full_int(struct sprd_i2c *i2c_dev, int enable)
175 {
176 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
177 
178 	if (enable)
179 		tmp |= FULL_INTEN;
180 	else
181 		tmp &= ~FULL_INTEN;
182 
183 	writel(tmp, i2c_dev->base + I2C_CTL);
184 };
185 
186 static void sprd_i2c_set_fifo_empty_int(struct sprd_i2c *i2c_dev, int enable)
187 {
188 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
189 
190 	if (enable)
191 		tmp |= EMPTY_INTEN;
192 	else
193 		tmp &= ~EMPTY_INTEN;
194 
195 	writel(tmp, i2c_dev->base + I2C_CTL);
196 };
197 
198 static void sprd_i2c_opt_start(struct sprd_i2c *i2c_dev)
199 {
200 	u32 tmp = readl(i2c_dev->base + I2C_CTL);
201 
202 	writel(tmp | I2C_START, i2c_dev->base + I2C_CTL);
203 }
204 
205 static void sprd_i2c_opt_mode(struct sprd_i2c *i2c_dev, int rw)
206 {
207 	u32 cmd = readl(i2c_dev->base + I2C_CTL) & ~I2C_MODE;
208 
209 	writel(cmd | rw << 3, i2c_dev->base + I2C_CTL);
210 }
211 
212 static void sprd_i2c_data_transfer(struct sprd_i2c *i2c_dev)
213 {
214 	u32 i2c_count = i2c_dev->count;
215 	u32 need_tran = i2c_count <= I2C_FIFO_DEEP ? i2c_count : I2C_FIFO_DEEP;
216 	struct i2c_msg *msg = i2c_dev->msg;
217 
218 	if (msg->flags & I2C_M_RD) {
219 		sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, I2C_FIFO_FULL_THLD);
220 		i2c_dev->count -= I2C_FIFO_FULL_THLD;
221 		i2c_dev->buf += I2C_FIFO_FULL_THLD;
222 
223 		/*
224 		 * If the read data count is larger than rx fifo full threshold,
225 		 * we should enable the rx fifo full interrupt to read data
226 		 * again.
227 		 */
228 		if (i2c_dev->count >= I2C_FIFO_FULL_THLD)
229 			sprd_i2c_set_fifo_full_int(i2c_dev, 1);
230 	} else {
231 		sprd_i2c_write_bytes(i2c_dev, i2c_dev->buf, need_tran);
232 		i2c_dev->buf += need_tran;
233 		i2c_dev->count -= need_tran;
234 
235 		/*
236 		 * If the write data count is arger than tx fifo depth which
237 		 * means we can not write all data in one time, then we should
238 		 * enable the tx fifo empty interrupt to write again.
239 		 */
240 		if (i2c_count > I2C_FIFO_DEEP)
241 			sprd_i2c_set_fifo_empty_int(i2c_dev, 1);
242 	}
243 }
244 
245 static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap,
246 			       struct i2c_msg *msg, bool is_last_msg)
247 {
248 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
249 	unsigned long time_left;
250 
251 	i2c_dev->msg = msg;
252 	i2c_dev->buf = msg->buf;
253 	i2c_dev->count = msg->len;
254 
255 	reinit_completion(&i2c_dev->complete);
256 	sprd_i2c_reset_fifo(i2c_dev);
257 	sprd_i2c_set_devaddr(i2c_dev, msg);
258 	sprd_i2c_set_count(i2c_dev, msg->len);
259 
260 	if (msg->flags & I2C_M_RD) {
261 		sprd_i2c_opt_mode(i2c_dev, 1);
262 		sprd_i2c_send_stop(i2c_dev, 1);
263 	} else {
264 		sprd_i2c_opt_mode(i2c_dev, 0);
265 		sprd_i2c_send_stop(i2c_dev, !!is_last_msg);
266 	}
267 
268 	/*
269 	 * We should enable rx fifo full interrupt to get data when receiving
270 	 * full data.
271 	 */
272 	if (msg->flags & I2C_M_RD)
273 		sprd_i2c_set_fifo_full_int(i2c_dev, 1);
274 	else
275 		sprd_i2c_data_transfer(i2c_dev);
276 
277 	sprd_i2c_opt_start(i2c_dev);
278 
279 	time_left = wait_for_completion_timeout(&i2c_dev->complete,
280 				msecs_to_jiffies(I2C_XFER_TIMEOUT));
281 	if (!time_left)
282 		return -ETIMEDOUT;
283 
284 	return i2c_dev->err;
285 }
286 
287 static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap,
288 				struct i2c_msg *msgs, int num)
289 {
290 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
291 	int im, ret;
292 
293 	ret = pm_runtime_get_sync(i2c_dev->dev);
294 	if (ret < 0)
295 		return ret;
296 
297 	for (im = 0; im < num - 1; im++) {
298 		ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im], 0);
299 		if (ret)
300 			goto err_msg;
301 	}
302 
303 	ret = sprd_i2c_handle_msg(i2c_adap, &msgs[im++], 1);
304 
305 err_msg:
306 	pm_runtime_mark_last_busy(i2c_dev->dev);
307 	pm_runtime_put_autosuspend(i2c_dev->dev);
308 
309 	return ret < 0 ? ret : im;
310 }
311 
312 static u32 sprd_i2c_func(struct i2c_adapter *adap)
313 {
314 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
315 }
316 
317 static const struct i2c_algorithm sprd_i2c_algo = {
318 	.master_xfer = sprd_i2c_master_xfer,
319 	.functionality = sprd_i2c_func,
320 };
321 
322 static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq)
323 {
324 	u32 apb_clk = i2c_dev->src_clk;
325 	/*
326 	 * From I2C databook, the prescale calculation formula:
327 	 * prescale = freq_i2c / (4 * freq_scl) - 1;
328 	 */
329 	u32 i2c_dvd = apb_clk / (4 * freq) - 1;
330 	/*
331 	 * From I2C databook, the high period of SCL clock is recommended as
332 	 * 40% (2/5), and the low period of SCL clock is recommended as 60%
333 	 * (3/5), then the formula should be:
334 	 * high = (prescale * 2 * 2) / 5
335 	 * low = (prescale * 2 * 3) / 5
336 	 */
337 	u32 high = ((i2c_dvd << 1) * 2) / 5;
338 	u32 low = ((i2c_dvd << 1) * 3) / 5;
339 	u32 div0 = I2C_ADDR_DVD0_CALC(high, low);
340 	u32 div1 = I2C_ADDR_DVD1_CALC(high, low);
341 
342 	writel(div0, i2c_dev->base + ADDR_DVD0);
343 	writel(div1, i2c_dev->base + ADDR_DVD1);
344 
345 	/* Start hold timing = hold time(us) * source clock */
346 	if (freq == I2C_MAX_FAST_MODE_FREQ)
347 		writel((6 * apb_clk) / 10000000, i2c_dev->base + ADDR_STA0_DVD);
348 	else if (freq == I2C_MAX_STANDARD_MODE_FREQ)
349 		writel((4 * apb_clk) / 1000000, i2c_dev->base + ADDR_STA0_DVD);
350 }
351 
352 static void sprd_i2c_enable(struct sprd_i2c *i2c_dev)
353 {
354 	u32 tmp = I2C_DVD_OPT;
355 
356 	writel(tmp, i2c_dev->base + I2C_CTL);
357 
358 	sprd_i2c_set_full_thld(i2c_dev, I2C_FIFO_FULL_THLD);
359 	sprd_i2c_set_empty_thld(i2c_dev, I2C_FIFO_EMPTY_THLD);
360 
361 	sprd_i2c_set_clk(i2c_dev, i2c_dev->bus_freq);
362 	sprd_i2c_reset_fifo(i2c_dev);
363 	sprd_i2c_clear_irq(i2c_dev);
364 
365 	tmp = readl(i2c_dev->base + I2C_CTL);
366 	writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL);
367 }
368 
369 static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id)
370 {
371 	struct sprd_i2c *i2c_dev = dev_id;
372 	struct i2c_msg *msg = i2c_dev->msg;
373 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
374 	u32 i2c_tran;
375 
376 	if (msg->flags & I2C_M_RD)
377 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
378 	else
379 		i2c_tran = i2c_dev->count;
380 
381 	/*
382 	 * If we got one ACK from slave when writing data, and we did not
383 	 * finish this transmission (i2c_tran is not zero), then we should
384 	 * continue to write data.
385 	 *
386 	 * For reading data, ack is always true, if i2c_tran is not 0 which
387 	 * means we still need to contine to read data from slave.
388 	 */
389 	if (i2c_tran && ack) {
390 		sprd_i2c_data_transfer(i2c_dev);
391 		return IRQ_HANDLED;
392 	}
393 
394 	i2c_dev->err = 0;
395 
396 	/*
397 	 * If we did not get one ACK from slave when writing data, we should
398 	 * return -EIO to notify users.
399 	 */
400 	if (!ack)
401 		i2c_dev->err = -EIO;
402 	else if (msg->flags & I2C_M_RD && i2c_dev->count)
403 		sprd_i2c_read_bytes(i2c_dev, i2c_dev->buf, i2c_dev->count);
404 
405 	/* Transmission is done and clear ack and start operation */
406 	sprd_i2c_clear_ack(i2c_dev);
407 	sprd_i2c_clear_start(i2c_dev);
408 	complete(&i2c_dev->complete);
409 
410 	return IRQ_HANDLED;
411 }
412 
413 static irqreturn_t sprd_i2c_isr(int irq, void *dev_id)
414 {
415 	struct sprd_i2c *i2c_dev = dev_id;
416 	struct i2c_msg *msg = i2c_dev->msg;
417 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
418 	u32 i2c_tran;
419 
420 	if (msg->flags & I2C_M_RD)
421 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
422 	else
423 		i2c_tran = i2c_dev->count;
424 
425 	/*
426 	 * If we did not get one ACK from slave when writing data, then we
427 	 * should finish this transmission since we got some errors.
428 	 *
429 	 * When writing data, if i2c_tran == 0 which means we have writen
430 	 * done all data, then we can finish this transmission.
431 	 *
432 	 * When reading data, if conut < rx fifo full threshold, which
433 	 * means we can read all data in one time, then we can finish this
434 	 * transmission too.
435 	 */
436 	if (!i2c_tran || !ack) {
437 		sprd_i2c_clear_start(i2c_dev);
438 		sprd_i2c_clear_irq(i2c_dev);
439 	}
440 
441 	sprd_i2c_set_fifo_empty_int(i2c_dev, 0);
442 	sprd_i2c_set_fifo_full_int(i2c_dev, 0);
443 
444 	return IRQ_WAKE_THREAD;
445 }
446 
447 static int sprd_i2c_clk_init(struct sprd_i2c *i2c_dev)
448 {
449 	struct clk *clk_i2c, *clk_parent;
450 
451 	clk_i2c = devm_clk_get(i2c_dev->dev, "i2c");
452 	if (IS_ERR(clk_i2c)) {
453 		dev_warn(i2c_dev->dev, "i2c%d can't get the i2c clock\n",
454 			 i2c_dev->adap.nr);
455 		clk_i2c = NULL;
456 	}
457 
458 	clk_parent = devm_clk_get(i2c_dev->dev, "source");
459 	if (IS_ERR(clk_parent)) {
460 		dev_warn(i2c_dev->dev, "i2c%d can't get the source clock\n",
461 			 i2c_dev->adap.nr);
462 		clk_parent = NULL;
463 	}
464 
465 	if (clk_set_parent(clk_i2c, clk_parent))
466 		i2c_dev->src_clk = clk_get_rate(clk_i2c);
467 	else
468 		i2c_dev->src_clk = 26000000;
469 
470 	dev_dbg(i2c_dev->dev, "i2c%d set source clock is %d\n",
471 		i2c_dev->adap.nr, i2c_dev->src_clk);
472 
473 	i2c_dev->clk = devm_clk_get(i2c_dev->dev, "enable");
474 	if (IS_ERR(i2c_dev->clk)) {
475 		dev_err(i2c_dev->dev, "i2c%d can't get the enable clock\n",
476 			i2c_dev->adap.nr);
477 		return PTR_ERR(i2c_dev->clk);
478 	}
479 
480 	return 0;
481 }
482 
483 static int sprd_i2c_probe(struct platform_device *pdev)
484 {
485 	struct device *dev = &pdev->dev;
486 	struct sprd_i2c *i2c_dev;
487 	u32 prop;
488 	int ret;
489 
490 	pdev->id = of_alias_get_id(dev->of_node, "i2c");
491 
492 	i2c_dev = devm_kzalloc(dev, sizeof(struct sprd_i2c), GFP_KERNEL);
493 	if (!i2c_dev)
494 		return -ENOMEM;
495 
496 	i2c_dev->base = devm_platform_ioremap_resource(pdev, 0);
497 	if (IS_ERR(i2c_dev->base))
498 		return PTR_ERR(i2c_dev->base);
499 
500 	i2c_dev->irq = platform_get_irq(pdev, 0);
501 	if (i2c_dev->irq < 0)
502 		return i2c_dev->irq;
503 
504 	i2c_set_adapdata(&i2c_dev->adap, i2c_dev);
505 	init_completion(&i2c_dev->complete);
506 	snprintf(i2c_dev->adap.name, sizeof(i2c_dev->adap.name),
507 		 "%s", "sprd-i2c");
508 
509 	i2c_dev->bus_freq = I2C_MAX_STANDARD_MODE_FREQ;
510 	i2c_dev->adap.owner = THIS_MODULE;
511 	i2c_dev->dev = dev;
512 	i2c_dev->adap.retries = 3;
513 	i2c_dev->adap.algo = &sprd_i2c_algo;
514 	i2c_dev->adap.algo_data = i2c_dev;
515 	i2c_dev->adap.dev.parent = dev;
516 	i2c_dev->adap.nr = pdev->id;
517 	i2c_dev->adap.dev.of_node = dev->of_node;
518 
519 	if (!of_property_read_u32(dev->of_node, "clock-frequency", &prop))
520 		i2c_dev->bus_freq = prop;
521 
522 	/* We only support 100k and 400k now, otherwise will return error. */
523 	if (i2c_dev->bus_freq != I2C_MAX_STANDARD_MODE_FREQ &&
524 	    i2c_dev->bus_freq != I2C_MAX_FAST_MODE_FREQ)
525 		return -EINVAL;
526 
527 	ret = sprd_i2c_clk_init(i2c_dev);
528 	if (ret)
529 		return ret;
530 
531 	platform_set_drvdata(pdev, i2c_dev);
532 
533 	ret = clk_prepare_enable(i2c_dev->clk);
534 	if (ret)
535 		return ret;
536 
537 	sprd_i2c_enable(i2c_dev);
538 
539 	pm_runtime_set_autosuspend_delay(i2c_dev->dev, SPRD_I2C_PM_TIMEOUT);
540 	pm_runtime_use_autosuspend(i2c_dev->dev);
541 	pm_runtime_set_active(i2c_dev->dev);
542 	pm_runtime_enable(i2c_dev->dev);
543 
544 	ret = pm_runtime_get_sync(i2c_dev->dev);
545 	if (ret < 0)
546 		goto err_rpm_put;
547 
548 	ret = devm_request_threaded_irq(dev, i2c_dev->irq,
549 		sprd_i2c_isr, sprd_i2c_isr_thread,
550 		IRQF_NO_SUSPEND | IRQF_ONESHOT,
551 		pdev->name, i2c_dev);
552 	if (ret) {
553 		dev_err(&pdev->dev, "failed to request irq %d\n", i2c_dev->irq);
554 		goto err_rpm_put;
555 	}
556 
557 	ret = i2c_add_numbered_adapter(&i2c_dev->adap);
558 	if (ret) {
559 		dev_err(&pdev->dev, "add adapter failed\n");
560 		goto err_rpm_put;
561 	}
562 
563 	pm_runtime_mark_last_busy(i2c_dev->dev);
564 	pm_runtime_put_autosuspend(i2c_dev->dev);
565 	return 0;
566 
567 err_rpm_put:
568 	pm_runtime_put_noidle(i2c_dev->dev);
569 	pm_runtime_disable(i2c_dev->dev);
570 	clk_disable_unprepare(i2c_dev->clk);
571 	return ret;
572 }
573 
574 static int sprd_i2c_remove(struct platform_device *pdev)
575 {
576 	struct sprd_i2c *i2c_dev = platform_get_drvdata(pdev);
577 	int ret;
578 
579 	ret = pm_runtime_get_sync(i2c_dev->dev);
580 	if (ret < 0)
581 		return ret;
582 
583 	i2c_del_adapter(&i2c_dev->adap);
584 	clk_disable_unprepare(i2c_dev->clk);
585 
586 	pm_runtime_put_noidle(i2c_dev->dev);
587 	pm_runtime_disable(i2c_dev->dev);
588 
589 	return 0;
590 }
591 
592 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *dev)
593 {
594 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
595 
596 	i2c_mark_adapter_suspended(&i2c_dev->adap);
597 	return pm_runtime_force_suspend(dev);
598 }
599 
600 static int __maybe_unused sprd_i2c_resume_noirq(struct device *dev)
601 {
602 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
603 
604 	i2c_mark_adapter_resumed(&i2c_dev->adap);
605 	return pm_runtime_force_resume(dev);
606 }
607 
608 static int __maybe_unused sprd_i2c_runtime_suspend(struct device *dev)
609 {
610 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
611 
612 	clk_disable_unprepare(i2c_dev->clk);
613 
614 	return 0;
615 }
616 
617 static int __maybe_unused sprd_i2c_runtime_resume(struct device *dev)
618 {
619 	struct sprd_i2c *i2c_dev = dev_get_drvdata(dev);
620 	int ret;
621 
622 	ret = clk_prepare_enable(i2c_dev->clk);
623 	if (ret)
624 		return ret;
625 
626 	sprd_i2c_enable(i2c_dev);
627 
628 	return 0;
629 }
630 
631 static const struct dev_pm_ops sprd_i2c_pm_ops = {
632 	SET_RUNTIME_PM_OPS(sprd_i2c_runtime_suspend,
633 			   sprd_i2c_runtime_resume, NULL)
634 
635 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sprd_i2c_suspend_noirq,
636 				      sprd_i2c_resume_noirq)
637 };
638 
639 static const struct of_device_id sprd_i2c_of_match[] = {
640 	{ .compatible = "sprd,sc9860-i2c", },
641 	{},
642 };
643 
644 static struct platform_driver sprd_i2c_driver = {
645 	.probe = sprd_i2c_probe,
646 	.remove = sprd_i2c_remove,
647 	.driver = {
648 		   .name = "sprd-i2c",
649 		   .of_match_table = sprd_i2c_of_match,
650 		   .pm = &sprd_i2c_pm_ops,
651 	},
652 };
653 
654 module_platform_driver(sprd_i2c_driver);
655 
656 MODULE_DESCRIPTION("Spreadtrum I2C master controller driver");
657 MODULE_LICENSE("GPL v2");
658