xref: /openbmc/linux/drivers/i2c/busses/i2c-xlp9xx.c (revision 6c33a6f4)
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 
195 		/*
196 		 * We expect at least 2 interrupts for I2C_M_RECV_LEN
197 		 * transactions. The length is updated during the first
198 		 * interrupt, and the buffer contents are only copied
199 		 * during subsequent interrupts. If in case the interrupts
200 		 * get merged we would complete the transaction without
201 		 * copying out the bytes from RX fifo. To avoid this now we
202 		 * drain the fifo as and when data is available.
203 		 * We drained the rlen byte already, decrement total length
204 		 * by one.
205 		 */
206 
207 		len--;
208 		if (rlen > I2C_SMBUS_BLOCK_MAX || rlen == 0) {
209 			rlen = 0;	/*abort transfer */
210 			priv->msg_buf_remaining = 0;
211 			priv->msg_len = 0;
212 			xlp9xx_i2c_update_rlen(priv);
213 			return;
214 		}
215 
216 		*buf++ = rlen;
217 		if (priv->client_pec)
218 			++rlen; /* account for error check byte */
219 		/* update remaining bytes and message length */
220 		priv->msg_buf_remaining = rlen;
221 		priv->msg_len = rlen + 1;
222 		xlp9xx_i2c_update_rlen(priv);
223 		priv->len_recv = false;
224 	}
225 
226 	len = min(priv->msg_buf_remaining, len);
227 	for (i = 0; i < len; i++, buf++)
228 		*buf = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_MRXFIFO);
229 
230 	priv->msg_buf_remaining -= len;
231 	priv->msg_buf = buf;
232 
233 	if (priv->msg_buf_remaining)
234 		xlp9xx_i2c_update_rx_fifo_thres(priv);
235 }
236 
237 static irqreturn_t xlp9xx_i2c_isr(int irq, void *dev_id)
238 {
239 	struct xlp9xx_i2c_dev *priv = dev_id;
240 	u32 status;
241 
242 	status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_INTST);
243 	if (status == 0)
244 		return IRQ_NONE;
245 
246 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTST, status);
247 	if (status & XLP9XX_I2C_STATUS_ERRMASK) {
248 		priv->msg_err = status;
249 		goto xfer_done;
250 	}
251 
252 	/* SADDR ACK for SMBUS_QUICK */
253 	if ((status & XLP9XX_I2C_INTEN_SADDR) && (priv->msg_len == 0))
254 		goto xfer_done;
255 
256 	if (!priv->msg_read) {
257 		if (status & XLP9XX_I2C_INTEN_MFIFOEMTY) {
258 			/* TX FIFO got empty, fill it up again */
259 			if (priv->msg_buf_remaining)
260 				xlp9xx_i2c_fill_tx_fifo(priv);
261 			else
262 				xlp9xx_i2c_mask_irq(priv,
263 						    XLP9XX_I2C_INTEN_MFIFOEMTY);
264 		}
265 	} else {
266 		if (status & (XLP9XX_I2C_INTEN_DATADONE |
267 			      XLP9XX_I2C_INTEN_MFIFOHI)) {
268 			/* data is in FIFO, read it */
269 			if (priv->msg_buf_remaining)
270 				xlp9xx_i2c_drain_rx_fifo(priv);
271 		}
272 	}
273 
274 	/* Transfer complete */
275 	if (status & XLP9XX_I2C_INTEN_DATADONE)
276 		goto xfer_done;
277 
278 	return IRQ_HANDLED;
279 
280 xfer_done:
281 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
282 	complete(&priv->msg_complete);
283 	return IRQ_HANDLED;
284 }
285 
286 static int xlp9xx_i2c_check_bus_status(struct xlp9xx_i2c_dev *priv)
287 {
288 	u32 status;
289 	u32 busy_timeout = XLP9XX_I2C_BUSY_TIMEOUT;
290 
291 	while (busy_timeout) {
292 		status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_STATUS);
293 		if ((status & XLP9XX_I2C_STATUS_BUSY) == 0)
294 			break;
295 
296 		busy_timeout--;
297 		usleep_range(1000, 1100);
298 	}
299 
300 	if (!busy_timeout)
301 		return -EIO;
302 
303 	return 0;
304 }
305 
306 static int xlp9xx_i2c_init(struct xlp9xx_i2c_dev *priv)
307 {
308 	u32 prescale;
309 
310 	/*
311 	 * The controller uses 5 * SCL clock internally.
312 	 * So prescale value should be divided by 5.
313 	 */
314 	prescale = DIV_ROUND_UP(priv->ip_clk_hz, priv->clk_hz);
315 	prescale = ((prescale - 8) / 5) - 1;
316 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_RST);
317 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, XLP9XX_I2C_CTRL_EN |
318 			     XLP9XX_I2C_CTRL_MASTER);
319 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_DIV, prescale);
320 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
321 
322 	return 0;
323 }
324 
325 static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg,
326 			       int last_msg)
327 {
328 	unsigned long timeleft;
329 	u32 intr_mask, cmd, val, len;
330 
331 	priv->msg_buf = msg->buf;
332 	priv->msg_buf_remaining = priv->msg_len = msg->len;
333 	priv->msg_err = 0;
334 	priv->msg_read = (msg->flags & I2C_M_RD);
335 	reinit_completion(&priv->msg_complete);
336 
337 	/* Reset FIFO */
338 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_MFIFOCTRL,
339 			     XLP9XX_I2C_MFIFOCTRL_RST);
340 
341 	/* set slave addr */
342 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_SLAVEADDR,
343 			     (msg->addr << XLP9XX_I2C_SLAVEADDR_ADDR_SHIFT) |
344 			     (priv->msg_read ? XLP9XX_I2C_SLAVEADDR_RW : 0));
345 
346 	/* Build control word for transfer */
347 	val = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_CTRL);
348 	if (!priv->msg_read)
349 		val &= ~XLP9XX_I2C_CTRL_FIFORD;
350 	else
351 		val |= XLP9XX_I2C_CTRL_FIFORD;	/* read */
352 
353 	if (msg->flags & I2C_M_TEN)
354 		val |= XLP9XX_I2C_CTRL_ADDMODE;	/* 10-bit address mode*/
355 	else
356 		val &= ~XLP9XX_I2C_CTRL_ADDMODE;
357 
358 	priv->len_recv = msg->flags & I2C_M_RECV_LEN;
359 	len = priv->len_recv ? I2C_SMBUS_BLOCK_MAX + 2 : msg->len;
360 	priv->client_pec = msg->flags & I2C_CLIENT_PEC;
361 
362 	/* set FIFO threshold if reading */
363 	if (priv->msg_read)
364 		xlp9xx_i2c_update_rx_fifo_thres(priv);
365 
366 	/* set data length to be transferred */
367 	val = (val & ~XLP9XX_I2C_CTRL_MCTLEN_MASK) |
368 	      (len << XLP9XX_I2C_CTRL_MCTLEN_SHIFT);
369 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, val);
370 
371 	/* fill fifo during tx */
372 	if (!priv->msg_read)
373 		xlp9xx_i2c_fill_tx_fifo(priv);
374 
375 	/* set interrupt mask */
376 	intr_mask = (XLP9XX_I2C_INTEN_ARLOST | XLP9XX_I2C_INTEN_BUSERR |
377 		     XLP9XX_I2C_INTEN_NACKADDR | XLP9XX_I2C_INTEN_DATADONE);
378 
379 	if (priv->msg_read) {
380 		intr_mask |= XLP9XX_I2C_INTEN_MFIFOHI;
381 		if (msg->len == 0)
382 			intr_mask |= XLP9XX_I2C_INTEN_SADDR;
383 	} else {
384 		if (msg->len == 0)
385 			intr_mask |= XLP9XX_I2C_INTEN_SADDR;
386 		else
387 			intr_mask |= XLP9XX_I2C_INTEN_MFIFOEMTY;
388 	}
389 	xlp9xx_i2c_unmask_irq(priv, intr_mask);
390 
391 	/* set cmd reg */
392 	cmd = XLP9XX_I2C_CMD_START;
393 	if (msg->len)
394 		cmd |= (priv->msg_read ?
395 			XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE);
396 	if (last_msg)
397 		cmd |= XLP9XX_I2C_CMD_STOP;
398 
399 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, cmd);
400 
401 	timeleft = msecs_to_jiffies(XLP9XX_I2C_TIMEOUT_MS);
402 	timeleft = wait_for_completion_timeout(&priv->msg_complete, timeleft);
403 
404 	if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) {
405 		dev_dbg(priv->dev, "transfer error %x!\n", priv->msg_err);
406 		xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, XLP9XX_I2C_CMD_STOP);
407 		return -EIO;
408 	} else if (priv->msg_err & XLP9XX_I2C_INTEN_NACKADDR) {
409 		return -ENXIO;
410 	}
411 
412 	if (timeleft == 0) {
413 		dev_dbg(priv->dev, "i2c transfer timed out!\n");
414 		xlp9xx_i2c_init(priv);
415 		return -ETIMEDOUT;
416 	}
417 
418 	/* update msg->len with actual received length */
419 	if (msg->flags & I2C_M_RECV_LEN) {
420 		if (!priv->msg_len)
421 			return -EPROTO;
422 		msg->len = priv->msg_len;
423 	}
424 	return 0;
425 }
426 
427 static int xlp9xx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
428 			   int num)
429 {
430 	int i, ret;
431 	struct xlp9xx_i2c_dev *priv = i2c_get_adapdata(adap);
432 
433 	ret = xlp9xx_i2c_check_bus_status(priv);
434 	if (ret) {
435 		xlp9xx_i2c_init(priv);
436 		ret = xlp9xx_i2c_check_bus_status(priv);
437 		if (ret)
438 			return ret;
439 	}
440 
441 	for (i = 0; i < num; i++) {
442 		ret = xlp9xx_i2c_xfer_msg(priv, &msgs[i], i == num - 1);
443 		if (ret != 0)
444 			return ret;
445 	}
446 
447 	return num;
448 }
449 
450 static u32 xlp9xx_i2c_functionality(struct i2c_adapter *adapter)
451 {
452 	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA |
453 			I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR;
454 }
455 
456 static const struct i2c_algorithm xlp9xx_i2c_algo = {
457 	.master_xfer = xlp9xx_i2c_xfer,
458 	.functionality = xlp9xx_i2c_functionality,
459 };
460 
461 static int xlp9xx_i2c_get_frequency(struct platform_device *pdev,
462 				    struct xlp9xx_i2c_dev *priv)
463 {
464 	struct clk *clk;
465 	u32 freq;
466 	int err;
467 
468 	clk = devm_clk_get(&pdev->dev, NULL);
469 	if (IS_ERR(clk)) {
470 		priv->ip_clk_hz = XLP9XX_I2C_IP_CLK_FREQ;
471 		dev_dbg(&pdev->dev, "using default input frequency %u\n",
472 			priv->ip_clk_hz);
473 	} else {
474 		priv->ip_clk_hz = clk_get_rate(clk);
475 	}
476 
477 	err = device_property_read_u32(&pdev->dev, "clock-frequency", &freq);
478 	if (err) {
479 		freq = XLP9XX_I2C_DEFAULT_FREQ;
480 		dev_dbg(&pdev->dev, "using default frequency %u\n", freq);
481 	} else if (freq == 0 || freq > XLP9XX_I2C_HIGH_FREQ) {
482 		dev_warn(&pdev->dev, "invalid frequency %u, using default\n",
483 			 freq);
484 		freq = XLP9XX_I2C_DEFAULT_FREQ;
485 	}
486 	priv->clk_hz = freq;
487 
488 	return 0;
489 }
490 
491 static int xlp9xx_i2c_smbus_setup(struct xlp9xx_i2c_dev *priv,
492 				  struct platform_device *pdev)
493 {
494 	if (!priv->alert_data.irq)
495 		return -EINVAL;
496 
497 	priv->ara = i2c_setup_smbus_alert(&priv->adapter, &priv->alert_data);
498 	if (!priv->ara)
499 		return -ENODEV;
500 
501 	return 0;
502 }
503 
504 static int xlp9xx_i2c_probe(struct platform_device *pdev)
505 {
506 	struct xlp9xx_i2c_dev *priv;
507 	struct resource *res;
508 	int err = 0;
509 
510 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
511 	if (!priv)
512 		return -ENOMEM;
513 
514 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
515 	priv->base = devm_ioremap_resource(&pdev->dev, res);
516 	if (IS_ERR(priv->base))
517 		return PTR_ERR(priv->base);
518 
519 	priv->irq = platform_get_irq(pdev, 0);
520 	if (priv->irq <= 0) {
521 		dev_err(&pdev->dev, "invalid irq!\n");
522 		return priv->irq;
523 	}
524 	/* SMBAlert irq */
525 	priv->alert_data.irq = platform_get_irq(pdev, 1);
526 	if (priv->alert_data.irq <= 0)
527 		priv->alert_data.irq = 0;
528 
529 	xlp9xx_i2c_get_frequency(pdev, priv);
530 	xlp9xx_i2c_init(priv);
531 
532 	err = devm_request_irq(&pdev->dev, priv->irq, xlp9xx_i2c_isr, 0,
533 			       pdev->name, priv);
534 	if (err) {
535 		dev_err(&pdev->dev, "IRQ request failed!\n");
536 		return err;
537 	}
538 
539 	init_completion(&priv->msg_complete);
540 	priv->adapter.dev.parent = &pdev->dev;
541 	priv->adapter.algo = &xlp9xx_i2c_algo;
542 	priv->adapter.class = I2C_CLASS_HWMON;
543 	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&pdev->dev));
544 	priv->adapter.dev.of_node = pdev->dev.of_node;
545 	priv->dev = &pdev->dev;
546 
547 	snprintf(priv->adapter.name, sizeof(priv->adapter.name), "xlp9xx-i2c");
548 	i2c_set_adapdata(&priv->adapter, priv);
549 
550 	err = i2c_add_adapter(&priv->adapter);
551 	if (err)
552 		return err;
553 
554 	err = xlp9xx_i2c_smbus_setup(priv, pdev);
555 	if (err)
556 		dev_dbg(&pdev->dev, "No active SMBus alert %d\n", err);
557 
558 	platform_set_drvdata(pdev, priv);
559 	dev_dbg(&pdev->dev, "I2C bus:%d added\n", priv->adapter.nr);
560 
561 	return 0;
562 }
563 
564 static int xlp9xx_i2c_remove(struct platform_device *pdev)
565 {
566 	struct xlp9xx_i2c_dev *priv;
567 
568 	priv = platform_get_drvdata(pdev);
569 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_INTEN, 0);
570 	synchronize_irq(priv->irq);
571 	i2c_del_adapter(&priv->adapter);
572 	xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CTRL, 0);
573 
574 	return 0;
575 }
576 
577 static const struct of_device_id xlp9xx_i2c_of_match[] = {
578 	{ .compatible = "netlogic,xlp980-i2c", },
579 	{ /* sentinel */ },
580 };
581 MODULE_DEVICE_TABLE(of, xlp9xx_i2c_of_match);
582 
583 #ifdef CONFIG_ACPI
584 static const struct acpi_device_id xlp9xx_i2c_acpi_ids[] = {
585 	{"BRCM9007", 0},
586 	{"CAV9007",  0},
587 	{}
588 };
589 MODULE_DEVICE_TABLE(acpi, xlp9xx_i2c_acpi_ids);
590 #endif
591 
592 static struct platform_driver xlp9xx_i2c_driver = {
593 	.probe = xlp9xx_i2c_probe,
594 	.remove = xlp9xx_i2c_remove,
595 	.driver = {
596 		.name = "xlp9xx-i2c",
597 		.of_match_table = xlp9xx_i2c_of_match,
598 		.acpi_match_table = ACPI_PTR(xlp9xx_i2c_acpi_ids),
599 	},
600 };
601 
602 module_platform_driver(xlp9xx_i2c_driver);
603 
604 MODULE_AUTHOR("Subhendu Sekhar Behera <sbehera@broadcom.com>");
605 MODULE_DESCRIPTION("XLP9XX/5XX I2C Bus Controller Driver");
606 MODULE_LICENSE("GPL v2");
607