xref: /linux/drivers/i2c/busses/i2c-xlp9xx.c (revision b9b77222d4ff6b5bb8f5d87fca20de0910618bb9)
1 /*
2  * Copyright (c) 2003-2015 Broadcom Corporation
3  *
4  * This file is licensed under the terms of the GNU General Public
5  * License version 2. This program is licensed "as is" without any
6  * warranty of any kind, whether express or implied.
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/clk.h>
11 #include <linux/completion.h>
12 #include <linux/i2c.h>
13 #include <linux/i2c-smbus.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/delay.h>
21 
22 #define XLP9XX_I2C_DIV			0x0
23 #define XLP9XX_I2C_CTRL			0x1
24 #define XLP9XX_I2C_CMD			0x2
25 #define XLP9XX_I2C_STATUS		0x3
26 #define XLP9XX_I2C_MTXFIFO		0x4
27 #define XLP9XX_I2C_MRXFIFO		0x5
28 #define XLP9XX_I2C_MFIFOCTRL		0x6
29 #define XLP9XX_I2C_STXFIFO		0x7
30 #define XLP9XX_I2C_SRXFIFO		0x8
31 #define XLP9XX_I2C_SFIFOCTRL		0x9
32 #define XLP9XX_I2C_SLAVEADDR		0xA
33 #define XLP9XX_I2C_OWNADDR		0xB
34 #define XLP9XX_I2C_FIFOWCNT		0xC
35 #define XLP9XX_I2C_INTEN		0xD
36 #define XLP9XX_I2C_INTST		0xE
37 #define XLP9XX_I2C_WAITCNT		0xF
38 #define XLP9XX_I2C_TIMEOUT		0X10
39 #define XLP9XX_I2C_GENCALLADDR		0x11
40 
41 #define XLP9XX_I2C_STATUS_BUSY		BIT(0)
42 
43 #define XLP9XX_I2C_CMD_START		BIT(7)
44 #define XLP9XX_I2C_CMD_STOP		BIT(6)
45 #define XLP9XX_I2C_CMD_READ		BIT(5)
46 #define XLP9XX_I2C_CMD_WRITE		BIT(4)
47 #define XLP9XX_I2C_CMD_ACK		BIT(3)
48 
49 #define XLP9XX_I2C_CTRL_MCTLEN_SHIFT	16
50 #define XLP9XX_I2C_CTRL_MCTLEN_MASK	0xffff0000
51 #define XLP9XX_I2C_CTRL_RST		BIT(8)
52 #define XLP9XX_I2C_CTRL_EN		BIT(6)
53 #define XLP9XX_I2C_CTRL_MASTER		BIT(4)
54 #define XLP9XX_I2C_CTRL_FIFORD		BIT(1)
55 #define XLP9XX_I2C_CTRL_ADDMODE		BIT(0)
56 
57 #define XLP9XX_I2C_INTEN_NACKADDR	BIT(25)
58 #define XLP9XX_I2C_INTEN_SADDR		BIT(13)
59 #define XLP9XX_I2C_INTEN_DATADONE	BIT(12)
60 #define XLP9XX_I2C_INTEN_ARLOST		BIT(11)
61 #define XLP9XX_I2C_INTEN_MFIFOFULL	BIT(4)
62 #define XLP9XX_I2C_INTEN_MFIFOEMTY	BIT(3)
63 #define XLP9XX_I2C_INTEN_MFIFOHI	BIT(2)
64 #define XLP9XX_I2C_INTEN_BUSERR		BIT(0)
65 
66 #define XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT		8
67 #define XLP9XX_I2C_MFIFOCTRL_LOTH_SHIFT		0
68 #define XLP9XX_I2C_MFIFOCTRL_RST		BIT(16)
69 
70 #define XLP9XX_I2C_SLAVEADDR_RW			BIT(0)
71 #define XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT		1
72 
73 #define XLP9XX_I2C_IP_CLK_FREQ		133000000UL
74 #define XLP9XX_I2C_DEFAULT_FREQ		100000
75 #define XLP9XX_I2C_HIGH_FREQ		400000
76 #define XLP9XX_I2C_FIFO_SIZE		0x80U
77 #define XLP9XX_I2C_TIMEOUT_MS		1000
78 #define XLP9XX_I2C_BUSY_TIMEOUT		50
79 
80 #define XLP9XX_I2C_FIFO_WCNT_MASK	0xff
81 #define XLP9XX_I2C_STATUS_ERRMASK	(XLP9XX_I2C_INTEN_ARLOST | \
82 			XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_BUSERR)
83 
84 struct xlp9xx_i2c_dev {
85 	struct device *dev;
86 	struct i2c_adapter adapter;
87 	struct completion msg_complete;
88 	struct i2c_smbus_alert_setup alert_data;
89 	struct i2c_client *ara;
90 	int irq;
91 	bool msg_read;
92 	bool len_recv;
93 	bool client_pec;
94 	u32 __iomem *base;
95 	u32 msg_buf_remaining;
96 	u32 msg_len;
97 	u32 ip_clk_hz;
98 	u32 clk_hz;
99 	u32 msg_err;
100 	u8 *msg_buf;
101 };
102 
103 static inline void xlp9xx_write_i2c_reg(struct xlp9xx_i2c_dev *priv,
104 					unsigned long reg, u32 val)
105 {
106 	writel(val, priv->base + reg);
107 }
108 
109 static inline u32 xlp9xx_read_i2c_reg(struct xlp9xx_i2c_dev *priv,
110 				      unsigned long reg)
111 {
112 	return readl(priv->base + reg);
113 }
114 
115 static void xlp9xx_i2c_mask_irq(struct xlp9xx_i2c_dev *priv, u32 mask)
116 {
117 	u32 inten;
118 
119 	inten = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) & ~mask;
120 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, inten);
121 }
122 
123 static void xlp9xx_i2c_unmask_irq(struct xlp9xx_i2c_dev *priv, u32 mask)
124 {
125 	u32 inten;
126 
127 	inten = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTEN) | mask;
128 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, inten);
129 }
130 
131 static void xlp9xx_i2c_update_rx_fifo_thres(struct xlp9xx_i2c_dev *priv)
132 {
133 	u32 thres;
134 
135 	if (priv->len_recv)
136 		/* interrupt after the first read to examine
137 		 * the length byte before proceeding further
138 		 */
139 		thres = 1;
140 	else if (priv->msg_buf_remaining > XLP9XX_I2C_FIFO_SIZE)
141 		thres = XLP9XX_I2C_FIFO_SIZE;
142 	else
143 		thres = priv->msg_buf_remaining;
144 
145 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL,
146 			     thres << XLP9XX_I2C_MFIFOCTRL_HITH_SHIFT);
147 }
148 
149 static void xlp9xx_i2c_fill_tx_fifo(struct xlp9xx_i2c_dev *priv)
150 {
151 	u32 len, i;
152 	u8 *buf = priv->msg_buf;
153 
154 	len = min(priv->msg_buf_remaining, XLP9XX_I2C_FIFO_SIZE);
155 	for (i = 0; i < len; i++)
156 		xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MTXFIFO, buf[i]);
157 	priv->msg_buf_remaining -= len;
158 	priv->msg_buf += len;
159 }
160 
161 static void xlp9xx_i2c_update_rlen(struct xlp9xx_i2c_dev *priv)
162 {
163 	u32 val, len;
164 
165 	/*
166 	 * Update receive length. Re-read len to get the latest value,
167 	 * and then add 4 to have a minimum value that can be safely
168 	 * written. This is to account for the byte read above, the
169 	 * transfer in progress and any delays in the register I/O
170 	 */
171 	val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL);
172 	len = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_FIFOWCNT) &
173 				  XLP9XX_I2C_FIFO_WCNT_MASK;
174 	len = max_t(u32, priv->msg_len, len + 4);
175 	if (len >= I2C_SMBUS_BLOCK_MAX + 2)
176 		return;
177 	val = (val & ~XLP9XX_I2C_CTRL_MCTLEN_MASK) |
178 			(len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT);
179 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val);
180 }
181 
182 static void xlp9xx_i2c_drain_rx_fifo(struct xlp9xx_i2c_dev *priv)
183 {
184 	u32 len, i;
185 	u8 rlen, *buf = priv->msg_buf;
186 
187 	len = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_FIFOWCNT) &
188 				  XLP9XX_I2C_FIFO_WCNT_MASK;
189 	if (!len)
190 		return;
191 	if (priv->len_recv) {
192 		/* read length byte */
193 		rlen = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
194 		if (rlen > I2C_SMBUS_BLOCK_MAX || rlen == 0) {
195 			rlen = 0;	/*abort transfer */
196 			priv->msg_buf_remaining = 0;
197 			priv->msg_len = 0;
198 		} else {
199 			*buf++ = rlen;
200 			if (priv->client_pec)
201 				++rlen; /* account for error check byte */
202 			/* update remaining bytes and message length */
203 			priv->msg_buf_remaining = rlen;
204 			priv->msg_len = rlen + 1;
205 		}
206 		xlp9xx_i2c_update_rlen(priv);
207 		priv->len_recv = false;
208 	} else {
209 		len = min(priv->msg_buf_remaining, len);
210 		for (i = 0; i < len; i++, buf++)
211 			*buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
212 
213 		priv->msg_buf_remaining -= len;
214 	}
215 
216 	priv->msg_buf = buf;
217 
218 	if (priv->msg_buf_remaining)
219 		xlp9xx_i2c_update_rx_fifo_thres(priv);
220 }
221 
222 static irqreturn_t xlp9xx_i2c_isr(int irq, void *dev_id)
223 {
224 	struct xlp9xx_i2c_dev *priv = dev_id;
225 	u32 status;
226 
227 	status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTST);
228 	if (status == 0)
229 		return IRQ_NONE;
230 
231 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTST, status);
232 	if (status & XLP9XX_I2C_STATUS_ERRMASK) {
233 		priv->msg_err = status;
234 		goto xfer_done;
235 	}
236 
237 	/* SADDR ACK for SMBUS_QUICK */
238 	if ((status & XLP9XX_I2C_INTEN_SADDR) && (priv->msg_len == 0))
239 		goto xfer_done;
240 
241 	if (!priv->msg_read) {
242 		if (status & XLP9XX_I2C_INTEN_MFIFOEMTY) {
243 			/* TX FIFO got empty, fill it up again */
244 			if (priv->msg_buf_remaining)
245 				xlp9xx_i2c_fill_tx_fifo(priv);
246 			else
247 				xlp9xx_i2c_mask_irq(priv,
248 						    XLP9XX_I2C_INTEN_MFIFOEMTY);
249 		}
250 	} else {
251 		if (status & (XLP9XX_I2C_INTEN_DATADONE |
252 			      XLP9XX_I2C_INTEN_MFIFOHI)) {
253 			/* data is in FIFO, read it */
254 			if (priv->msg_buf_remaining)
255 				xlp9xx_i2c_drain_rx_fifo(priv);
256 		}
257 	}
258 
259 	/* Transfer complete */
260 	if (status & XLP9XX_I2C_INTEN_DATADONE)
261 		goto xfer_done;
262 
263 	return IRQ_HANDLED;
264 
265 xfer_done:
266 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
267 	complete(&priv->msg_complete);
268 	return IRQ_HANDLED;
269 }
270 
271 static int xlp9xx_i2c_check_bus_status(struct xlp9xx_i2c_dev *priv)
272 {
273 	u32 status;
274 	u32 busy_timeout = XLP9XX_I2C_BUSY_TIMEOUT;
275 
276 	while (busy_timeout) {
277 		status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_STATUS);
278 		if ((status & XLP9XX_I2C_STATUS_BUSY) == 0)
279 			break;
280 
281 		busy_timeout--;
282 		usleep_range(1000, 1100);
283 	}
284 
285 	if (!busy_timeout)
286 		return -EIO;
287 
288 	return 0;
289 }
290 
291 static int xlp9xx_i2c_init(struct xlp9xx_i2c_dev *priv)
292 {
293 	u32 prescale;
294 
295 	/*
296 	 * The controller uses 5 * SCL clock internally.
297 	 * So prescale value should be divided by 5.
298 	 */
299 	prescale = DIV_ROUND_UP(priv->ip_clk_hz, priv->clk_hz);
300 	prescale = ((prescale - 8) / 5) - 1;
301 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_RST);
302 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_EN |
303 			     XLP9XX_I2C_CTRL_MASTER);
304 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_DIV, prescale);
305 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
306 
307 	return 0;
308 }
309 
310 static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg,
311 			       int last_msg)
312 {
313 	unsigned long timeleft;
314 	u32 intr_mask, cmd, val, len;
315 
316 	priv->msg_buf = msg->buf;
317 	priv->msg_buf_remaining = priv->msg_len = msg->len;
318 	priv->msg_err = 0;
319 	priv->msg_read = (msg->flags & I2C_M_RD);
320 	reinit_completion(&priv->msg_complete);
321 
322 	/* Reset FIFO */
323 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL,
324 			     XLP9XX_I2C_MFIFOCTRL_RST);
325 
326 	/* set slave addr */
327 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_SLAVEADDR,
328 			     (msg->addr << XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT) |
329 			     (priv->msg_read ? XLP9XX_I2C_SLAVEADDR_RW : 0));
330 
331 	/* Build control word for transfer */
332 	val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL);
333 	if (!priv->msg_read)
334 		val &= ~XLP9XX_I2C_CTRL_FIFORD;
335 	else
336 		val |= XLP9XX_I2C_CTRL_FIFORD;	/* read */
337 
338 	if (msg->flags & I2C_M_TEN)
339 		val |= XLP9XX_I2C_CTRL_ADDMODE;	/* 10-bit address mode*/
340 	else
341 		val &= ~XLP9XX_I2C_CTRL_ADDMODE;
342 
343 	priv->len_recv = msg->flags & I2C_M_RECV_LEN;
344 	len = priv->len_recv ? I2C_SMBUS_BLOCK_MAX + 2 : msg->len;
345 	priv->client_pec = msg->flags & I2C_CLIENT_PEC;
346 
347 	/* set FIFO threshold if reading */
348 	if (priv->msg_read)
349 		xlp9xx_i2c_update_rx_fifo_thres(priv);
350 
351 	/* set data length to be transferred */
352 	val = (val & ~XLP9XX_I2C_CTRL_MCTLEN_MASK) |
353 	      (len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT);
354 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val);
355 
356 	/* fill fifo during tx */
357 	if (!priv->msg_read)
358 		xlp9xx_i2c_fill_tx_fifo(priv);
359 
360 	/* set interrupt mask */
361 	intr_mask = (XLP9XX_I2C_INTEN_ARLOST | XLP9XX_I2C_INTEN_BUSERR |
362 		     XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_DATADONE);
363 
364 	if (priv->msg_read) {
365 		intr_mask |= XLP9XX_I2C_INTEN_MFIFOHI;
366 		if (msg->len == 0)
367 			intr_mask |= XLP9XX_I2C_INTEN_SADDR;
368 	} else {
369 		if (msg->len == 0)
370 			intr_mask |= XLP9XX_I2C_INTEN_SADDR;
371 		else
372 			intr_mask |= XLP9XX_I2C_INTEN_MFIFOEMTY;
373 	}
374 	xlp9xx_i2c_unmask_irq(priv, intr_mask);
375 
376 	/* set cmd reg */
377 	cmd = XLP9XX_I2C_CMD_START;
378 	if (msg->len)
379 		cmd |= (priv->msg_read ?
380 			XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE);
381 	if (last_msg)
382 		cmd |= XLP9XX_I2C_CMD_STOP;
383 
384 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, cmd);
385 
386 	timeleft = msecs_to_jiffies(XLP9XX_I2C_TIMEOUT_MS);
387 	timeleft = wait_for_completion_timeout(&priv->msg_complete, timeleft);
388 
389 	if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) {
390 		dev_dbg(priv->dev, "transfer error %x!\n", priv->msg_err);
391 		xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, XLP9XX_I2C_CMD_STOP);
392 		return -EIO;
393 	} else if (priv->msg_err & XLP9XX_I2C_INTEN_NACKADDR) {
394 		return -ENXIO;
395 	}
396 
397 	if (timeleft == 0) {
398 		dev_dbg(priv->dev, "i2c transfer timed out!\n");
399 		xlp9xx_i2c_init(priv);
400 		return -ETIMEDOUT;
401 	}
402 
403 	/* update msg->len with actual received length */
404 	if (msg->flags & I2C_M_RECV_LEN) {
405 		if (!priv->msg_len)
406 			return -EPROTO;
407 		msg->len = priv->msg_len;
408 	}
409 	return 0;
410 }
411 
412 static int xlp9xx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
413 			   int num)
414 {
415 	int i, ret;
416 	struct xlp9xx_i2c_dev *priv = i2c_get_adapdata(adap);
417 
418 	ret = xlp9xx_i2c_check_bus_status(priv);
419 	if (ret) {
420 		xlp9xx_i2c_init(priv);
421 		ret = xlp9xx_i2c_check_bus_status(priv);
422 		if (ret)
423 			return ret;
424 	}
425 
426 	for (i = 0; i < num; i++) {
427 		ret = xlp9xx_i2c_xfer_msg(priv, &msgs[i], i == num - 1);
428 		if (ret != 0)
429 			return ret;
430 	}
431 
432 	return num;
433 }
434 
435 static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter)
436 {
437 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA |
438 			I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR;
439 }
440 
441 static const struct i2c_algorithm xlp9xx_i2c_algo = {
442 	.master_xfer = xlp9xx_i2c_xfer,
443 	.functionality = xlp9xx_i2c_functionality,
444 };
445 
446 static int xlp9xx_i2c_get_frequency(struct platform_device *pdev,
447 				    struct xlp9xx_i2c_dev *priv)
448 {
449 	struct clk *clk;
450 	u32 freq;
451 	int err;
452 
453 	clk = devm_clk_get(&pdev->dev, NULL);
454 	if (IS_ERR(clk)) {
455 		priv->ip_clk_hz = XLP9XX_I2C_IP_CLK_FREQ;
456 		dev_dbg(&pdev->dev, "using default input frequency %u\n",
457 			priv->ip_clk_hz);
458 	} else {
459 		priv->ip_clk_hz = clk_get_rate(clk);
460 	}
461 
462 	err = device_property_read_u32(&pdev->dev, "clock-frequency", &freq);
463 	if (err) {
464 		freq = XLP9XX_I2C_DEFAULT_FREQ;
465 		dev_dbg(&pdev->dev, "using default frequency %u\n", freq);
466 	} else if (freq == 0 || freq > XLP9XX_I2C_HIGH_FREQ) {
467 		dev_warn(&pdev->dev, "invalid frequency %u, using default\n",
468 			 freq);
469 		freq = XLP9XX_I2C_DEFAULT_FREQ;
470 	}
471 	priv->clk_hz = freq;
472 
473 	return 0;
474 }
475 
476 static int xlp9xx_i2c_smbus_setup(struct xlp9xx_i2c_dev *priv,
477 				  struct platform_device *pdev)
478 {
479 	if (!priv->alert_data.irq)
480 		return -EINVAL;
481 
482 	priv->ara = i2c_setup_smbus_alert(&priv->adapter, &priv->alert_data);
483 	if (!priv->ara)
484 		return -ENODEV;
485 
486 	return 0;
487 }
488 
489 static int xlp9xx_i2c_probe(struct platform_device *pdev)
490 {
491 	struct xlp9xx_i2c_dev *priv;
492 	struct resource *res;
493 	int err = 0;
494 
495 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
496 	if (!priv)
497 		return -ENOMEM;
498 
499 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
500 	priv->base = devm_ioremap_resource(&pdev->dev, res);
501 	if (IS_ERR(priv->base))
502 		return PTR_ERR(priv->base);
503 
504 	priv->irq = platform_get_irq(pdev, 0);
505 	if (priv->irq <= 0) {
506 		dev_err(&pdev->dev, "invalid irq!\n");
507 		return priv->irq;
508 	}
509 	/* SMBAlert irq */
510 	priv->alert_data.irq = platform_get_irq(pdev, 1);
511 	if (priv->alert_data.irq <= 0)
512 		priv->alert_data.irq = 0;
513 
514 	xlp9xx_i2c_get_frequency(pdev, priv);
515 	xlp9xx_i2c_init(priv);
516 
517 	err = devm_request_irq(&pdev->dev, priv->irq, xlp9xx_i2c_isr, 0,
518 			       pdev->name, priv);
519 	if (err) {
520 		dev_err(&pdev->dev, "IRQ request failed!\n");
521 		return err;
522 	}
523 
524 	init_completion(&priv->msg_complete);
525 	priv->adapter.dev.parent = &pdev->dev;
526 	priv->adapter.algo = &xlp9xx_i2c_algo;
527 	priv->adapter.class = I2C_CLASS_HWMON;
528 	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev));
529 	priv->adapter.dev.of_node = pdev->dev.of_node;
530 	priv->dev = &pdev->dev;
531 
532 	snprintf(priv->adapter.name, sizeof(priv->adapter.name), "xlp9xx-i2c");
533 	i2c_set_adapdata(&priv->adapter, priv);
534 
535 	err = i2c_add_adapter(&priv->adapter);
536 	if (err)
537 		return err;
538 
539 	err = xlp9xx_i2c_smbus_setup(priv, pdev);
540 	if (err)
541 		dev_dbg(&pdev->dev, "No active SMBus alert %d\n", err);
542 
543 	platform_set_drvdata(pdev, priv);
544 	dev_dbg(&pdev->dev, "I2C bus:%d added\n", priv->adapter.nr);
545 
546 	return 0;
547 }
548 
549 static int xlp9xx_i2c_remove(struct platform_device *pdev)
550 {
551 	struct xlp9xx_i2c_dev *priv;
552 
553 	priv = platform_get_drvdata(pdev);
554 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
555 	synchronize_irq(priv->irq);
556 	i2c_del_adapter(&priv->adapter);
557 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, 0);
558 
559 	return 0;
560 }
561 
562 static const struct of_device_id xlp9xx_i2c_of_match[] = {
563 	{ .compatible = "netlogic,xlp980-i2c", },
564 	{ /* sentinel */ },
565 };
566 MODULE_DEVICE_TABLE(of, xlp9xx_i2c_of_match);
567 
568 #ifdef CONFIG_ACPI
569 static const struct acpi_device_id xlp9xx_i2c_acpi_ids[] = {
570 	{"BRCM9007", 0},
571 	{"CAV9007",  0},
572 	{}
573 };
574 MODULE_DEVICE_TABLE(acpi, xlp9xx_i2c_acpi_ids);
575 #endif
576 
577 static struct platform_driver xlp9xx_i2c_driver = {
578 	.probe = xlp9xx_i2c_probe,
579 	.remove = xlp9xx_i2c_remove,
580 	.driver = {
581 		.name = "xlp9xx-i2c",
582 		.of_match_table = xlp9xx_i2c_of_match,
583 		.acpi_match_table = ACPI_PTR(xlp9xx_i2c_acpi_ids),
584 	},
585 };
586 
587 module_platform_driver(xlp9xx_i2c_driver);
588 
589 MODULE_AUTHOR("Subhendu Sekhar Behera <sbehera@broadcom.com>");
590 MODULE_DESCRIPTION("XLP9XX/5XX I2C Bus Controller Driver");
591 MODULE_LICENSE("GPL v2");
592