xref: /openbmc/linux/drivers/i2c/busses/i2c-hisi.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * HiSilicon I2C Controller Driver for Kunpeng SoC
4  *
5  * Copyright (c) 2021 HiSilicon Technologies Co., Ltd.
6  */
7 
8 #include <linux/bits.h>
9 #include <linux/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/completion.h>
12 #include <linux/i2c.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/platform_device.h>
18 #include <linux/property.h>
19 #include <linux/units.h>
20 
21 #define HISI_I2C_FRAME_CTRL		0x0000
22 #define   HISI_I2C_FRAME_CTRL_SPEED_MODE	GENMASK(1, 0)
23 #define   HISI_I2C_FRAME_CTRL_ADDR_TEN	BIT(2)
24 #define HISI_I2C_SLV_ADDR		0x0004
25 #define   HISI_I2C_SLV_ADDR_VAL		GENMASK(9, 0)
26 #define   HISI_I2C_SLV_ADDR_GC_S_MODE	BIT(10)
27 #define   HISI_I2C_SLV_ADDR_GC_S_EN	BIT(11)
28 #define HISI_I2C_CMD_TXDATA		0x0008
29 #define   HISI_I2C_CMD_TXDATA_DATA	GENMASK(7, 0)
30 #define   HISI_I2C_CMD_TXDATA_RW	BIT(8)
31 #define   HISI_I2C_CMD_TXDATA_P_EN	BIT(9)
32 #define   HISI_I2C_CMD_TXDATA_SR_EN	BIT(10)
33 #define HISI_I2C_RXDATA			0x000c
34 #define   HISI_I2C_RXDATA_DATA		GENMASK(7, 0)
35 #define HISI_I2C_SS_SCL_HCNT		0x0010
36 #define HISI_I2C_SS_SCL_LCNT		0x0014
37 #define HISI_I2C_FS_SCL_HCNT		0x0018
38 #define HISI_I2C_FS_SCL_LCNT		0x001c
39 #define HISI_I2C_HS_SCL_HCNT		0x0020
40 #define HISI_I2C_HS_SCL_LCNT		0x0024
41 #define HISI_I2C_FIFO_CTRL		0x0028
42 #define   HISI_I2C_FIFO_RX_CLR		BIT(0)
43 #define   HISI_I2C_FIFO_TX_CLR		BIT(1)
44 #define   HISI_I2C_FIFO_RX_AF_THRESH	GENMASK(7, 2)
45 #define   HISI_I2C_FIFO_TX_AE_THRESH	GENMASK(13, 8)
46 #define HISI_I2C_FIFO_STATE		0x002c
47 #define   HISI_I2C_FIFO_STATE_RX_RERR	BIT(0)
48 #define   HISI_I2C_FIFO_STATE_RX_WERR	BIT(1)
49 #define   HISI_I2C_FIFO_STATE_RX_EMPTY	BIT(3)
50 #define   HISI_I2C_FIFO_STATE_TX_RERR	BIT(6)
51 #define   HISI_I2C_FIFO_STATE_TX_WERR	BIT(7)
52 #define   HISI_I2C_FIFO_STATE_TX_FULL	BIT(11)
53 #define HISI_I2C_SDA_HOLD		0x0030
54 #define   HISI_I2C_SDA_HOLD_TX		GENMASK(15, 0)
55 #define   HISI_I2C_SDA_HOLD_RX		GENMASK(23, 16)
56 #define HISI_I2C_FS_SPK_LEN		0x0038
57 #define   HISI_I2C_FS_SPK_LEN_CNT	GENMASK(7, 0)
58 #define HISI_I2C_HS_SPK_LEN		0x003c
59 #define   HISI_I2C_HS_SPK_LEN_CNT	GENMASK(7, 0)
60 #define HISI_I2C_INT_MSTAT		0x0044
61 #define HISI_I2C_INT_CLR		0x0048
62 #define HISI_I2C_INT_MASK		0x004C
63 #define HISI_I2C_TRANS_STATE		0x0050
64 #define HISI_I2C_TRANS_ERR		0x0054
65 #define HISI_I2C_VERSION		0x0058
66 
67 #define HISI_I2C_INT_ALL	GENMASK(4, 0)
68 #define HISI_I2C_INT_TRANS_CPLT	BIT(0)
69 #define HISI_I2C_INT_TRANS_ERR	BIT(1)
70 #define HISI_I2C_INT_FIFO_ERR	BIT(2)
71 #define HISI_I2C_INT_RX_FULL	BIT(3)
72 #define HISI_I2C_INT_TX_EMPTY	BIT(4)
73 #define HISI_I2C_INT_ERR \
74 	(HISI_I2C_INT_TRANS_ERR | HISI_I2C_INT_FIFO_ERR)
75 
76 #define HISI_I2C_STD_SPEED_MODE		0
77 #define HISI_I2C_FAST_SPEED_MODE	1
78 #define HISI_I2C_HIGH_SPEED_MODE	2
79 
80 #define HISI_I2C_TX_FIFO_DEPTH		64
81 #define HISI_I2C_RX_FIFO_DEPTH		64
82 #define HISI_I2C_TX_F_AE_THRESH		1
83 #define HISI_I2C_RX_F_AF_THRESH		60
84 
85 #define NSEC_TO_CYCLES(ns, clk_rate_khz) \
86 	DIV_ROUND_UP_ULL((clk_rate_khz) * (ns), NSEC_PER_MSEC)
87 
88 struct hisi_i2c_controller {
89 	struct i2c_adapter adapter;
90 	void __iomem *iobase;
91 	struct device *dev;
92 	struct clk *clk;
93 	int irq;
94 
95 	/* Intermediates for recording the transfer process */
96 	struct completion *completion;
97 	struct i2c_msg *msgs;
98 	int msg_num;
99 	int msg_tx_idx;
100 	int buf_tx_idx;
101 	int msg_rx_idx;
102 	int buf_rx_idx;
103 	u16 tar_addr;
104 	u32 xfer_err;
105 
106 	/* I2C bus configuration */
107 	struct i2c_timings t;
108 	u32 clk_rate_khz;
109 	u32 spk_len;
110 };
111 
112 static void hisi_i2c_enable_int(struct hisi_i2c_controller *ctlr, u32 mask)
113 {
114 	writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_MASK);
115 }
116 
117 static void hisi_i2c_disable_int(struct hisi_i2c_controller *ctlr, u32 mask)
118 {
119 	writel_relaxed((~mask) & HISI_I2C_INT_ALL, ctlr->iobase + HISI_I2C_INT_MASK);
120 }
121 
122 static void hisi_i2c_clear_int(struct hisi_i2c_controller *ctlr, u32 mask)
123 {
124 	writel_relaxed(mask, ctlr->iobase + HISI_I2C_INT_CLR);
125 }
126 
127 static void hisi_i2c_handle_errors(struct hisi_i2c_controller *ctlr)
128 {
129 	u32 int_err = ctlr->xfer_err, reg;
130 
131 	if (int_err & HISI_I2C_INT_FIFO_ERR) {
132 		reg = readl(ctlr->iobase + HISI_I2C_FIFO_STATE);
133 
134 		if (reg & HISI_I2C_FIFO_STATE_RX_RERR)
135 			dev_err(ctlr->dev, "rx fifo error read\n");
136 
137 		if (reg & HISI_I2C_FIFO_STATE_RX_WERR)
138 			dev_err(ctlr->dev, "rx fifo error write\n");
139 
140 		if (reg & HISI_I2C_FIFO_STATE_TX_RERR)
141 			dev_err(ctlr->dev, "tx fifo error read\n");
142 
143 		if (reg & HISI_I2C_FIFO_STATE_TX_WERR)
144 			dev_err(ctlr->dev, "tx fifo error write\n");
145 	}
146 }
147 
148 static int hisi_i2c_start_xfer(struct hisi_i2c_controller *ctlr)
149 {
150 	struct i2c_msg *msg = ctlr->msgs;
151 	u32 reg;
152 
153 	reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL);
154 	reg &= ~HISI_I2C_FRAME_CTRL_ADDR_TEN;
155 	if (msg->flags & I2C_M_TEN)
156 		reg |= HISI_I2C_FRAME_CTRL_ADDR_TEN;
157 	writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL);
158 
159 	reg = readl(ctlr->iobase + HISI_I2C_SLV_ADDR);
160 	reg &= ~HISI_I2C_SLV_ADDR_VAL;
161 	reg |= FIELD_PREP(HISI_I2C_SLV_ADDR_VAL, msg->addr);
162 	writel(reg, ctlr->iobase + HISI_I2C_SLV_ADDR);
163 
164 	reg = readl(ctlr->iobase + HISI_I2C_FIFO_CTRL);
165 	reg |= HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR;
166 	writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL);
167 	reg &= ~(HISI_I2C_FIFO_RX_CLR | HISI_I2C_FIFO_TX_CLR);
168 	writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL);
169 
170 	hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL);
171 	hisi_i2c_enable_int(ctlr, HISI_I2C_INT_ALL);
172 
173 	return 0;
174 }
175 
176 static void hisi_i2c_reset_xfer(struct hisi_i2c_controller *ctlr)
177 {
178 	ctlr->msg_num = 0;
179 	ctlr->xfer_err = 0;
180 	ctlr->msg_tx_idx = 0;
181 	ctlr->msg_rx_idx = 0;
182 	ctlr->buf_tx_idx = 0;
183 	ctlr->buf_rx_idx = 0;
184 }
185 
186 /*
187  * Initialize the transfer information and start the I2C bus transfer.
188  * We only configure the transfer and do some pre/post works here, and
189  * wait for the transfer done. The major transfer process is performed
190  * in the IRQ handler.
191  */
192 static int hisi_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
193 				int num)
194 {
195 	struct hisi_i2c_controller *ctlr = i2c_get_adapdata(adap);
196 	DECLARE_COMPLETION_ONSTACK(done);
197 	int ret = num;
198 
199 	hisi_i2c_reset_xfer(ctlr);
200 	ctlr->completion = &done;
201 	ctlr->msg_num = num;
202 	ctlr->msgs = msgs;
203 
204 	hisi_i2c_start_xfer(ctlr);
205 
206 	if (!wait_for_completion_timeout(ctlr->completion, adap->timeout)) {
207 		hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL);
208 		synchronize_irq(ctlr->irq);
209 		i2c_recover_bus(&ctlr->adapter);
210 		dev_err(ctlr->dev, "bus transfer timeout\n");
211 		ret = -EIO;
212 	}
213 
214 	if (ctlr->xfer_err) {
215 		hisi_i2c_handle_errors(ctlr);
216 		ret = -EIO;
217 	}
218 
219 	hisi_i2c_reset_xfer(ctlr);
220 	ctlr->completion = NULL;
221 
222 	return ret;
223 }
224 
225 static u32 hisi_i2c_functionality(struct i2c_adapter *adap)
226 {
227 	return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL;
228 }
229 
230 static const struct i2c_algorithm hisi_i2c_algo = {
231 	.master_xfer	= hisi_i2c_master_xfer,
232 	.functionality	= hisi_i2c_functionality,
233 };
234 
235 static int hisi_i2c_read_rx_fifo(struct hisi_i2c_controller *ctlr)
236 {
237 	struct i2c_msg *cur_msg;
238 	u32 fifo_state;
239 
240 	while (ctlr->msg_rx_idx < ctlr->msg_num) {
241 		cur_msg = ctlr->msgs + ctlr->msg_rx_idx;
242 
243 		if (!(cur_msg->flags & I2C_M_RD)) {
244 			ctlr->msg_rx_idx++;
245 			continue;
246 		}
247 
248 		fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE);
249 		while (!(fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY) &&
250 		       ctlr->buf_rx_idx < cur_msg->len) {
251 			cur_msg->buf[ctlr->buf_rx_idx++] = readl(ctlr->iobase + HISI_I2C_RXDATA);
252 			fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE);
253 		}
254 
255 		if (ctlr->buf_rx_idx == cur_msg->len) {
256 			ctlr->buf_rx_idx = 0;
257 			ctlr->msg_rx_idx++;
258 		}
259 
260 		if (fifo_state & HISI_I2C_FIFO_STATE_RX_EMPTY)
261 			break;
262 	}
263 
264 	return 0;
265 }
266 
267 static void hisi_i2c_xfer_msg(struct hisi_i2c_controller *ctlr)
268 {
269 	int max_write = HISI_I2C_TX_FIFO_DEPTH;
270 	bool need_restart = false, last_msg;
271 	struct i2c_msg *cur_msg;
272 	u32 cmd, fifo_state;
273 
274 	while (ctlr->msg_tx_idx < ctlr->msg_num) {
275 		cur_msg = ctlr->msgs + ctlr->msg_tx_idx;
276 		last_msg = (ctlr->msg_tx_idx == ctlr->msg_num - 1);
277 
278 		/* Signal the SR bit when we start transferring a new message */
279 		if (ctlr->msg_tx_idx && !ctlr->buf_tx_idx)
280 			need_restart = true;
281 
282 		fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE);
283 		while (!(fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) &&
284 		       ctlr->buf_tx_idx < cur_msg->len && max_write) {
285 			cmd = 0;
286 
287 			if (need_restart) {
288 				cmd |= HISI_I2C_CMD_TXDATA_SR_EN;
289 				need_restart = false;
290 			}
291 
292 			/* Signal the STOP bit at the last frame of the last message */
293 			if (ctlr->buf_tx_idx == cur_msg->len - 1 && last_msg)
294 				cmd |= HISI_I2C_CMD_TXDATA_P_EN;
295 
296 			if (cur_msg->flags & I2C_M_RD)
297 				cmd |= HISI_I2C_CMD_TXDATA_RW;
298 			else
299 				cmd |= FIELD_PREP(HISI_I2C_CMD_TXDATA_DATA,
300 						  cur_msg->buf[ctlr->buf_tx_idx]);
301 
302 			writel(cmd, ctlr->iobase + HISI_I2C_CMD_TXDATA);
303 			ctlr->buf_tx_idx++;
304 			max_write--;
305 
306 			fifo_state = readl(ctlr->iobase + HISI_I2C_FIFO_STATE);
307 		}
308 
309 		/* Update the transfer index after per message transfer is done. */
310 		if (ctlr->buf_tx_idx == cur_msg->len) {
311 			ctlr->buf_tx_idx = 0;
312 			ctlr->msg_tx_idx++;
313 		}
314 
315 		if ((fifo_state & HISI_I2C_FIFO_STATE_TX_FULL) ||
316 		    max_write == 0)
317 			break;
318 	}
319 
320 	/*
321 	 * Disable the TX_EMPTY interrupt after finishing all the messages to
322 	 * avoid overwhelming the CPU.
323 	 */
324 	if (ctlr->msg_tx_idx == ctlr->msg_num)
325 		hisi_i2c_disable_int(ctlr, HISI_I2C_INT_TX_EMPTY);
326 }
327 
328 static irqreturn_t hisi_i2c_irq(int irq, void *context)
329 {
330 	struct hisi_i2c_controller *ctlr = context;
331 	u32 int_stat;
332 
333 	int_stat = readl(ctlr->iobase + HISI_I2C_INT_MSTAT);
334 	hisi_i2c_clear_int(ctlr, int_stat);
335 	if (!(int_stat & HISI_I2C_INT_ALL))
336 		return IRQ_NONE;
337 
338 	if (int_stat & HISI_I2C_INT_TX_EMPTY)
339 		hisi_i2c_xfer_msg(ctlr);
340 
341 	if (int_stat & HISI_I2C_INT_ERR) {
342 		ctlr->xfer_err = int_stat;
343 		goto out;
344 	}
345 
346 	/* Drain the rx fifo before finish the transfer */
347 	if (int_stat & (HISI_I2C_INT_TRANS_CPLT | HISI_I2C_INT_RX_FULL))
348 		hisi_i2c_read_rx_fifo(ctlr);
349 
350 out:
351 	/*
352 	 * Only use TRANS_CPLT to indicate the completion. On error cases we'll
353 	 * get two interrupts, INT_ERR first then TRANS_CPLT.
354 	 */
355 	if (int_stat & HISI_I2C_INT_TRANS_CPLT) {
356 		hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL);
357 		hisi_i2c_clear_int(ctlr, HISI_I2C_INT_ALL);
358 		complete(ctlr->completion);
359 	}
360 
361 	return IRQ_HANDLED;
362 }
363 
364 /*
365  * Helper function for calculating and configuring the HIGH and LOW
366  * periods of SCL clock. The caller will pass the ratio of the
367  * counts (divide / divisor) according to the target speed mode,
368  * and the target registers.
369  */
370 static void hisi_i2c_set_scl(struct hisi_i2c_controller *ctlr,
371 			     u32 divide, u32 divisor,
372 			     u32 reg_hcnt, u32 reg_lcnt)
373 {
374 	u32 total_cnt, t_scl_hcnt, t_scl_lcnt, scl_fall_cnt, scl_rise_cnt;
375 	u32 scl_hcnt, scl_lcnt;
376 
377 	/* Total SCL clock cycles per speed period */
378 	total_cnt = DIV_ROUND_UP_ULL(ctlr->clk_rate_khz * HZ_PER_KHZ, ctlr->t.bus_freq_hz);
379 	/* Total HIGH level SCL clock cycles including edges */
380 	t_scl_hcnt = DIV_ROUND_UP_ULL(total_cnt * divide, divisor);
381 	/* Total LOW level SCL clock cycles including edges */
382 	t_scl_lcnt = total_cnt - t_scl_hcnt;
383 	/* Fall edge SCL clock cycles */
384 	scl_fall_cnt = NSEC_TO_CYCLES(ctlr->t.scl_fall_ns, ctlr->clk_rate_khz);
385 	/* Rise edge SCL clock cycles */
386 	scl_rise_cnt = NSEC_TO_CYCLES(ctlr->t.scl_rise_ns, ctlr->clk_rate_khz);
387 
388 	/* Calculated HIGH and LOW periods of SCL clock */
389 	scl_hcnt = t_scl_hcnt - ctlr->spk_len - 7 - scl_fall_cnt;
390 	scl_lcnt = t_scl_lcnt - 1 - scl_rise_cnt;
391 
392 	writel(scl_hcnt, ctlr->iobase + reg_hcnt);
393 	writel(scl_lcnt, ctlr->iobase + reg_lcnt);
394 }
395 
396 static void hisi_i2c_configure_bus(struct hisi_i2c_controller *ctlr)
397 {
398 	u32 reg, sda_hold_cnt, speed_mode;
399 
400 	i2c_parse_fw_timings(ctlr->dev, &ctlr->t, true);
401 	ctlr->spk_len = NSEC_TO_CYCLES(ctlr->t.digital_filter_width_ns, ctlr->clk_rate_khz);
402 
403 	switch (ctlr->t.bus_freq_hz) {
404 	case I2C_MAX_FAST_MODE_FREQ:
405 		speed_mode = HISI_I2C_FAST_SPEED_MODE;
406 		hisi_i2c_set_scl(ctlr, 26, 76, HISI_I2C_FS_SCL_HCNT, HISI_I2C_FS_SCL_LCNT);
407 		break;
408 	case I2C_MAX_HIGH_SPEED_MODE_FREQ:
409 		speed_mode = HISI_I2C_HIGH_SPEED_MODE;
410 		hisi_i2c_set_scl(ctlr, 6, 22, HISI_I2C_HS_SCL_HCNT, HISI_I2C_HS_SCL_LCNT);
411 		break;
412 	case I2C_MAX_STANDARD_MODE_FREQ:
413 	default:
414 		speed_mode = HISI_I2C_STD_SPEED_MODE;
415 
416 		/* For default condition force the bus speed to standard mode. */
417 		ctlr->t.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
418 		hisi_i2c_set_scl(ctlr, 40, 87, HISI_I2C_SS_SCL_HCNT, HISI_I2C_SS_SCL_LCNT);
419 		break;
420 	}
421 
422 	reg = readl(ctlr->iobase + HISI_I2C_FRAME_CTRL);
423 	reg &= ~HISI_I2C_FRAME_CTRL_SPEED_MODE;
424 	reg |= FIELD_PREP(HISI_I2C_FRAME_CTRL_SPEED_MODE, speed_mode);
425 	writel(reg, ctlr->iobase + HISI_I2C_FRAME_CTRL);
426 
427 	sda_hold_cnt = NSEC_TO_CYCLES(ctlr->t.sda_hold_ns, ctlr->clk_rate_khz);
428 
429 	reg = FIELD_PREP(HISI_I2C_SDA_HOLD_TX, sda_hold_cnt);
430 	writel(reg, ctlr->iobase + HISI_I2C_SDA_HOLD);
431 
432 	writel(ctlr->spk_len, ctlr->iobase + HISI_I2C_FS_SPK_LEN);
433 
434 	reg = FIELD_PREP(HISI_I2C_FIFO_RX_AF_THRESH, HISI_I2C_RX_F_AF_THRESH);
435 	reg |= FIELD_PREP(HISI_I2C_FIFO_TX_AE_THRESH, HISI_I2C_TX_F_AE_THRESH);
436 	writel(reg, ctlr->iobase + HISI_I2C_FIFO_CTRL);
437 }
438 
439 static int hisi_i2c_probe(struct platform_device *pdev)
440 {
441 	struct hisi_i2c_controller *ctlr;
442 	struct device *dev = &pdev->dev;
443 	struct i2c_adapter *adapter;
444 	u64 clk_rate_hz;
445 	u32 hw_version;
446 	int ret;
447 
448 	ctlr = devm_kzalloc(dev, sizeof(*ctlr), GFP_KERNEL);
449 	if (!ctlr)
450 		return -ENOMEM;
451 
452 	ctlr->iobase = devm_platform_ioremap_resource(pdev, 0);
453 	if (IS_ERR(ctlr->iobase))
454 		return PTR_ERR(ctlr->iobase);
455 
456 	ctlr->irq = platform_get_irq(pdev, 0);
457 	if (ctlr->irq < 0)
458 		return ctlr->irq;
459 
460 	ctlr->dev = dev;
461 
462 	hisi_i2c_disable_int(ctlr, HISI_I2C_INT_ALL);
463 
464 	ret = devm_request_irq(dev, ctlr->irq, hisi_i2c_irq, 0, "hisi-i2c", ctlr);
465 	if (ret) {
466 		dev_err(dev, "failed to request irq handler, ret = %d\n", ret);
467 		return ret;
468 	}
469 
470 	ctlr->clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
471 	if (IS_ERR_OR_NULL(ctlr->clk)) {
472 		ret = device_property_read_u64(dev, "clk_rate", &clk_rate_hz);
473 		if (ret) {
474 			dev_err(dev, "failed to get clock frequency, ret = %d\n", ret);
475 			return ret;
476 		}
477 	} else {
478 		clk_rate_hz = clk_get_rate(ctlr->clk);
479 	}
480 
481 	ctlr->clk_rate_khz = DIV_ROUND_UP_ULL(clk_rate_hz, HZ_PER_KHZ);
482 
483 	hisi_i2c_configure_bus(ctlr);
484 
485 	adapter = &ctlr->adapter;
486 	snprintf(adapter->name, sizeof(adapter->name),
487 		 "HiSilicon I2C Controller %s", dev_name(dev));
488 	adapter->owner = THIS_MODULE;
489 	adapter->algo = &hisi_i2c_algo;
490 	adapter->dev.parent = dev;
491 	i2c_set_adapdata(adapter, ctlr);
492 
493 	ret = devm_i2c_add_adapter(dev, adapter);
494 	if (ret)
495 		return ret;
496 
497 	hw_version = readl(ctlr->iobase + HISI_I2C_VERSION);
498 	dev_info(ctlr->dev, "speed mode is %s. hw version 0x%x\n",
499 		 i2c_freq_mode_string(ctlr->t.bus_freq_hz), hw_version);
500 
501 	return 0;
502 }
503 
504 static const struct acpi_device_id hisi_i2c_acpi_ids[] = {
505 	{ "HISI03D1", 0 },
506 	{ }
507 };
508 MODULE_DEVICE_TABLE(acpi, hisi_i2c_acpi_ids);
509 
510 static const struct of_device_id hisi_i2c_dts_ids[] = {
511 	{ .compatible = "hisilicon,ascend910-i2c", },
512 	{ }
513 };
514 MODULE_DEVICE_TABLE(of, hisi_i2c_dts_ids);
515 
516 static struct platform_driver hisi_i2c_driver = {
517 	.probe		= hisi_i2c_probe,
518 	.driver		= {
519 		.name	= "hisi-i2c",
520 		.acpi_match_table = hisi_i2c_acpi_ids,
521 		.of_match_table = hisi_i2c_dts_ids,
522 	},
523 };
524 module_platform_driver(hisi_i2c_driver);
525 
526 MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>");
527 MODULE_DESCRIPTION("HiSilicon I2C Controller Driver");
528 MODULE_LICENSE("GPL");
529