1 /*
2  * X-Gene SLIMpro I2C Driver
3  *
4  * Copyright (c) 2014, Applied Micro Circuits Corporation
5  * Author: Feng Kan <fkan@apm.com>
6  * Author: Hieu Le <hnle@apm.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, see <http://www.gnu.org/licenses/>.
20  *
21  * This driver provides support for X-Gene SLIMpro I2C device access
22  * using the APM X-Gene SLIMpro mailbox driver.
23  *
24  */
25 #include <acpi/pcc.h>
26 #include <linux/acpi.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/i2c.h>
29 #include <linux/interrupt.h>
30 #include <linux/io.h>
31 #include <linux/mailbox_client.h>
32 #include <linux/module.h>
33 #include <linux/of.h>
34 #include <linux/platform_device.h>
35 #include <linux/version.h>
36 
37 #define MAILBOX_OP_TIMEOUT		1000	/* Operation time out in ms */
38 #define MAILBOX_I2C_INDEX		0
39 #define SLIMPRO_IIC_BUS			1	/* Use I2C bus 1 only */
40 
41 #define SMBUS_CMD_LEN			1
42 #define BYTE_DATA			1
43 #define WORD_DATA			2
44 #define BLOCK_DATA			3
45 
46 #define SLIMPRO_IIC_I2C_PROTOCOL	0
47 #define SLIMPRO_IIC_SMB_PROTOCOL	1
48 
49 #define SLIMPRO_IIC_READ		0
50 #define SLIMPRO_IIC_WRITE		1
51 
52 #define IIC_SMB_WITHOUT_DATA_LEN	0
53 #define IIC_SMB_WITH_DATA_LEN		1
54 
55 #define SLIMPRO_DEBUG_MSG		0
56 #define SLIMPRO_MSG_TYPE_SHIFT		28
57 #define SLIMPRO_DBG_SUBTYPE_I2C1READ	4
58 #define SLIMPRO_DBGMSG_TYPE_SHIFT	24
59 #define SLIMPRO_DBGMSG_TYPE_MASK	0x0F000000U
60 #define SLIMPRO_IIC_DEV_SHIFT		23
61 #define SLIMPRO_IIC_DEV_MASK		0x00800000U
62 #define SLIMPRO_IIC_DEVID_SHIFT		13
63 #define SLIMPRO_IIC_DEVID_MASK		0x007FE000U
64 #define SLIMPRO_IIC_RW_SHIFT		12
65 #define SLIMPRO_IIC_RW_MASK		0x00001000U
66 #define SLIMPRO_IIC_PROTO_SHIFT		11
67 #define SLIMPRO_IIC_PROTO_MASK		0x00000800U
68 #define SLIMPRO_IIC_ADDRLEN_SHIFT	8
69 #define SLIMPRO_IIC_ADDRLEN_MASK	0x00000700U
70 #define SLIMPRO_IIC_DATALEN_SHIFT	0
71 #define SLIMPRO_IIC_DATALEN_MASK	0x000000FFU
72 
73 /*
74  * SLIMpro I2C message encode
75  *
76  * dev		- Controller number (0-based)
77  * chip		- I2C chip address
78  * op		- SLIMPRO_IIC_READ or SLIMPRO_IIC_WRITE
79  * proto	- SLIMPRO_IIC_SMB_PROTOCOL or SLIMPRO_IIC_I2C_PROTOCOL
80  * addrlen	- Length of the address field
81  * datalen	- Length of the data field
82  */
83 #define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \
84 	((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \
85 	((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \
86 	SLIMPRO_DBGMSG_TYPE_MASK) | \
87 	((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \
88 	((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \
89 	((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \
90 	((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \
91 	((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \
92 	((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK))
93 
94 #define SLIMPRO_MSG_TYPE(v)             (((v) & 0xF0000000) >> 28)
95 
96 /*
97  * Encode for upper address for block data
98  */
99 #define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR			0x80000000
100 #define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a)	((u32) (((a) << 30) \
101 								& 0x40000000))
102 #define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a)		((u32) (((a) >> 12) \
103 								& 0x3FF00000))
104 #define SLIMPRO_IIC_ENCODE_ADDR(a)			((a) & 0x000FFFFF)
105 
106 #define SLIMPRO_IIC_MSG_DWORD_COUNT			3
107 
108 /* PCC related defines */
109 #define PCC_SIGNATURE			0x50424300
110 #define PCC_STS_CMD_COMPLETE		BIT(0)
111 #define PCC_STS_SCI_DOORBELL		BIT(1)
112 #define PCC_STS_ERR			BIT(2)
113 #define PCC_STS_PLAT_NOTIFY		BIT(3)
114 #define PCC_CMD_GENERATE_DB_INT		BIT(15)
115 
116 struct slimpro_i2c_dev {
117 	struct i2c_adapter adapter;
118 	struct device *dev;
119 	struct mbox_chan *mbox_chan;
120 	struct mbox_client mbox_client;
121 	int mbox_idx;
122 	struct completion rd_complete;
123 	u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1]; /* dma_buffer[0] is used for length */
124 	u32 *resp_msg;
125 	phys_addr_t comm_base_addr;
126 	void *pcc_comm_addr;
127 };
128 
129 #define to_slimpro_i2c_dev(cl)	\
130 		container_of(cl, struct slimpro_i2c_dev, mbox_client)
131 
132 /*
133  * This function tests and clears a bitmask then returns its old value
134  */
135 static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
136 {
137 	u16 ret, val;
138 
139 	val = le16_to_cpu(READ_ONCE(*addr));
140 	ret = val & mask;
141 	val &= ~mask;
142 	WRITE_ONCE(*addr, cpu_to_le16(val));
143 
144 	return ret;
145 }
146 
147 static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg)
148 {
149 	struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
150 
151 	/*
152 	 * Response message format:
153 	 * mssg[0] is the return code of the operation
154 	 * mssg[1] is the first data word
155 	 * mssg[2] is NOT used
156 	 */
157 	if (ctx->resp_msg)
158 		*ctx->resp_msg = ((u32 *)mssg)[1];
159 
160 	if (ctx->mbox_client.tx_block)
161 		complete(&ctx->rd_complete);
162 }
163 
164 static void slimpro_i2c_pcc_rx_cb(struct mbox_client *cl, void *msg)
165 {
166 	struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
167 	struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
168 
169 	/* Check if platform sends interrupt */
170 	if (!xgene_word_tst_and_clr(&generic_comm_base->status,
171 				    PCC_STS_SCI_DOORBELL))
172 		return;
173 
174 	if (xgene_word_tst_and_clr(&generic_comm_base->status,
175 				   PCC_STS_CMD_COMPLETE)) {
176 		msg = generic_comm_base + 1;
177 
178 		/* Response message msg[1] contains the return value. */
179 		if (ctx->resp_msg)
180 			*ctx->resp_msg = ((u32 *)msg)[1];
181 
182 		complete(&ctx->rd_complete);
183 	}
184 }
185 
186 static void slimpro_i2c_pcc_tx_prepare(struct slimpro_i2c_dev *ctx, u32 *msg)
187 {
188 	struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
189 	u32 *ptr = (void *)(generic_comm_base + 1);
190 	u16 status;
191 	int i;
192 
193 	WRITE_ONCE(generic_comm_base->signature,
194 		   cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx));
195 
196 	WRITE_ONCE(generic_comm_base->command,
197 		   cpu_to_le16(SLIMPRO_MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INT));
198 
199 	status = le16_to_cpu(READ_ONCE(generic_comm_base->status));
200 	status &= ~PCC_STS_CMD_COMPLETE;
201 	WRITE_ONCE(generic_comm_base->status, cpu_to_le16(status));
202 
203 	/* Copy the message to the PCC comm space */
204 	for (i = 0; i < SLIMPRO_IIC_MSG_DWORD_COUNT; i++)
205 		WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
206 }
207 
208 static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx)
209 {
210 	if (ctx->mbox_client.tx_block || !acpi_disabled) {
211 		if (!wait_for_completion_timeout(&ctx->rd_complete,
212 						 msecs_to_jiffies(MAILBOX_OP_TIMEOUT)))
213 			return -ETIMEDOUT;
214 	}
215 
216 	/* Check of invalid data or no device */
217 	if (*ctx->resp_msg == 0xffffffff)
218 		return -ENODEV;
219 
220 	return 0;
221 }
222 
223 static int slimpro_i2c_send_msg(struct slimpro_i2c_dev *ctx,
224 				u32 *msg,
225 				u32 *data)
226 {
227 	int rc;
228 
229 	ctx->resp_msg = data;
230 
231 	if (!acpi_disabled) {
232 		reinit_completion(&ctx->rd_complete);
233 		slimpro_i2c_pcc_tx_prepare(ctx, msg);
234 	}
235 
236 	rc = mbox_send_message(ctx->mbox_chan, msg);
237 	if (rc < 0)
238 		goto err;
239 
240 	rc = start_i2c_msg_xfer(ctx);
241 
242 err:
243 	if (!acpi_disabled)
244 		mbox_chan_txdone(ctx->mbox_chan, 0);
245 
246 	ctx->resp_msg = NULL;
247 
248 	return rc;
249 }
250 
251 static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip,
252 			  u32 addr, u32 addrlen, u32 protocol,
253 			  u32 readlen, u32 *data)
254 {
255 	u32 msg[3];
256 
257 	msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
258 					SLIMPRO_IIC_READ, protocol, addrlen, readlen);
259 	msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
260 	msg[2] = 0;
261 
262 	return slimpro_i2c_send_msg(ctx, msg, data);
263 }
264 
265 static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip,
266 			  u32 addr, u32 addrlen, u32 protocol, u32 writelen,
267 			  u32 data)
268 {
269 	u32 msg[3];
270 
271 	msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
272 					SLIMPRO_IIC_WRITE, protocol, addrlen, writelen);
273 	msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
274 	msg[2] = data;
275 
276 	return slimpro_i2c_send_msg(ctx, msg, msg);
277 }
278 
279 static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr,
280 			     u32 addrlen, u32 protocol, u32 readlen,
281 			     u32 with_data_len, void *data)
282 {
283 	dma_addr_t paddr;
284 	u32 msg[3];
285 	int rc;
286 
287 	paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE);
288 	if (dma_mapping_error(ctx->dev, paddr)) {
289 		dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
290 			ctx->dma_buffer);
291 		return -ENOMEM;
292 	}
293 
294 	msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ,
295 					protocol, addrlen, readlen);
296 	msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
297 		 SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) |
298 		 SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
299 		 SLIMPRO_IIC_ENCODE_ADDR(addr);
300 	msg[2] = (u32)paddr;
301 
302 	rc = slimpro_i2c_send_msg(ctx, msg, msg);
303 
304 	/* Copy to destination */
305 	memcpy(data, ctx->dma_buffer, readlen);
306 
307 	dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE);
308 	return rc;
309 }
310 
311 static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip,
312 			     u32 addr, u32 addrlen, u32 protocol, u32 writelen,
313 			     void *data)
314 {
315 	dma_addr_t paddr;
316 	u32 msg[3];
317 	int rc;
318 
319 	memcpy(ctx->dma_buffer, data, writelen);
320 	paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
321 			       DMA_TO_DEVICE);
322 	if (dma_mapping_error(ctx->dev, paddr)) {
323 		dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
324 			ctx->dma_buffer);
325 		return -ENOMEM;
326 	}
327 
328 	msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE,
329 					protocol, addrlen, writelen);
330 	msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
331 		 SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
332 		 SLIMPRO_IIC_ENCODE_ADDR(addr);
333 	msg[2] = (u32)paddr;
334 
335 	if (ctx->mbox_client.tx_block)
336 		reinit_completion(&ctx->rd_complete);
337 
338 	rc = slimpro_i2c_send_msg(ctx, msg, msg);
339 
340 	dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE);
341 	return rc;
342 }
343 
344 static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr,
345 				  unsigned short flags, char read_write,
346 				  u8 command, int size,
347 				  union i2c_smbus_data *data)
348 {
349 	struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap);
350 	int ret = -EOPNOTSUPP;
351 	u32 val;
352 
353 	switch (size) {
354 	case I2C_SMBUS_BYTE:
355 		if (read_write == I2C_SMBUS_READ) {
356 			ret = slimpro_i2c_rd(ctx, addr, 0, 0,
357 					     SLIMPRO_IIC_SMB_PROTOCOL,
358 					     BYTE_DATA, &val);
359 			data->byte = val;
360 		} else {
361 			ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
362 					     SLIMPRO_IIC_SMB_PROTOCOL,
363 					     0, 0);
364 		}
365 		break;
366 	case I2C_SMBUS_BYTE_DATA:
367 		if (read_write == I2C_SMBUS_READ) {
368 			ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
369 					     SLIMPRO_IIC_SMB_PROTOCOL,
370 					     BYTE_DATA, &val);
371 			data->byte = val;
372 		} else {
373 			val = data->byte;
374 			ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
375 					     SLIMPRO_IIC_SMB_PROTOCOL,
376 					     BYTE_DATA, val);
377 		}
378 		break;
379 	case I2C_SMBUS_WORD_DATA:
380 		if (read_write == I2C_SMBUS_READ) {
381 			ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
382 					     SLIMPRO_IIC_SMB_PROTOCOL,
383 					     WORD_DATA, &val);
384 			data->word = val;
385 		} else {
386 			val = data->word;
387 			ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
388 					     SLIMPRO_IIC_SMB_PROTOCOL,
389 					     WORD_DATA, val);
390 		}
391 		break;
392 	case I2C_SMBUS_BLOCK_DATA:
393 		if (read_write == I2C_SMBUS_READ) {
394 			ret = slimpro_i2c_blkrd(ctx, addr, command,
395 						SMBUS_CMD_LEN,
396 						SLIMPRO_IIC_SMB_PROTOCOL,
397 						I2C_SMBUS_BLOCK_MAX + 1,
398 						IIC_SMB_WITH_DATA_LEN,
399 						&data->block[0]);
400 
401 		} else {
402 			ret = slimpro_i2c_blkwr(ctx, addr, command,
403 						SMBUS_CMD_LEN,
404 						SLIMPRO_IIC_SMB_PROTOCOL,
405 						data->block[0] + 1,
406 						&data->block[0]);
407 		}
408 		break;
409 	case I2C_SMBUS_I2C_BLOCK_DATA:
410 		if (read_write == I2C_SMBUS_READ) {
411 			ret = slimpro_i2c_blkrd(ctx, addr,
412 						command,
413 						SMBUS_CMD_LEN,
414 						SLIMPRO_IIC_I2C_PROTOCOL,
415 						I2C_SMBUS_BLOCK_MAX,
416 						IIC_SMB_WITHOUT_DATA_LEN,
417 						&data->block[1]);
418 		} else {
419 			ret = slimpro_i2c_blkwr(ctx, addr, command,
420 						SMBUS_CMD_LEN,
421 						SLIMPRO_IIC_I2C_PROTOCOL,
422 						data->block[0],
423 						&data->block[1]);
424 		}
425 		break;
426 	default:
427 		break;
428 	}
429 	return ret;
430 }
431 
432 /*
433 * Return list of supported functionality.
434 */
435 static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter)
436 {
437 	return I2C_FUNC_SMBUS_BYTE |
438 		I2C_FUNC_SMBUS_BYTE_DATA |
439 		I2C_FUNC_SMBUS_WORD_DATA |
440 		I2C_FUNC_SMBUS_BLOCK_DATA |
441 		I2C_FUNC_SMBUS_I2C_BLOCK;
442 }
443 
444 static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = {
445 	.smbus_xfer = xgene_slimpro_i2c_xfer,
446 	.functionality = xgene_slimpro_i2c_func,
447 };
448 
449 static int xgene_slimpro_i2c_probe(struct platform_device *pdev)
450 {
451 	struct slimpro_i2c_dev *ctx;
452 	struct i2c_adapter *adapter;
453 	struct mbox_client *cl;
454 	int rc;
455 
456 	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
457 	if (!ctx)
458 		return -ENOMEM;
459 
460 	ctx->dev = &pdev->dev;
461 	platform_set_drvdata(pdev, ctx);
462 	cl = &ctx->mbox_client;
463 
464 	/* Request mailbox channel */
465 	cl->dev = &pdev->dev;
466 	init_completion(&ctx->rd_complete);
467 	cl->tx_tout = MAILBOX_OP_TIMEOUT;
468 	cl->knows_txdone = false;
469 	if (acpi_disabled) {
470 		cl->tx_block = true;
471 		cl->rx_callback = slimpro_i2c_rx_cb;
472 		ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX);
473 		if (IS_ERR(ctx->mbox_chan)) {
474 			dev_err(&pdev->dev, "i2c mailbox channel request failed\n");
475 			return PTR_ERR(ctx->mbox_chan);
476 		}
477 	} else {
478 		struct acpi_pcct_hw_reduced *cppc_ss;
479 
480 		if (device_property_read_u32(&pdev->dev, "pcc-channel",
481 					     &ctx->mbox_idx))
482 			ctx->mbox_idx = MAILBOX_I2C_INDEX;
483 
484 		cl->tx_block = false;
485 		cl->rx_callback = slimpro_i2c_pcc_rx_cb;
486 		ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
487 		if (IS_ERR(ctx->mbox_chan)) {
488 			dev_err(&pdev->dev, "PCC mailbox channel request failed\n");
489 			return PTR_ERR(ctx->mbox_chan);
490 		}
491 
492 		/*
493 		 * The PCC mailbox controller driver should
494 		 * have parsed the PCCT (global table of all
495 		 * PCC channels) and stored pointers to the
496 		 * subspace communication region in con_priv.
497 		 */
498 		cppc_ss = ctx->mbox_chan->con_priv;
499 		if (!cppc_ss) {
500 			dev_err(&pdev->dev, "PPC subspace not found\n");
501 			rc = -ENOENT;
502 			goto mbox_err;
503 		}
504 
505 		if (!ctx->mbox_chan->mbox->txdone_irq) {
506 			dev_err(&pdev->dev, "PCC IRQ not supported\n");
507 			rc = -ENOENT;
508 			goto mbox_err;
509 		}
510 
511 		/*
512 		 * This is the shared communication region
513 		 * for the OS and Platform to communicate over.
514 		 */
515 		ctx->comm_base_addr = cppc_ss->base_address;
516 		if (ctx->comm_base_addr) {
517 			ctx->pcc_comm_addr = memremap(ctx->comm_base_addr,
518 						      cppc_ss->length,
519 						      MEMREMAP_WB);
520 		} else {
521 			dev_err(&pdev->dev, "Failed to get PCC comm region\n");
522 			rc = -ENOENT;
523 			goto mbox_err;
524 		}
525 
526 		if (!ctx->pcc_comm_addr) {
527 			dev_err(&pdev->dev,
528 				"Failed to ioremap PCC comm region\n");
529 			rc = -ENOMEM;
530 			goto mbox_err;
531 		}
532 	}
533 	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
534 	if (rc)
535 		dev_warn(&pdev->dev, "Unable to set dma mask\n");
536 
537 	/* Setup I2C adapter */
538 	adapter = &ctx->adapter;
539 	snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C");
540 	adapter->algo = &xgene_slimpro_i2c_algorithm;
541 	adapter->class = I2C_CLASS_HWMON;
542 	adapter->dev.parent = &pdev->dev;
543 	adapter->dev.of_node = pdev->dev.of_node;
544 	ACPI_COMPANION_SET(&adapter->dev, ACPI_COMPANION(&pdev->dev));
545 	i2c_set_adapdata(adapter, ctx);
546 	rc = i2c_add_adapter(adapter);
547 	if (rc)
548 		goto mbox_err;
549 
550 	dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n");
551 	return 0;
552 
553 mbox_err:
554 	if (acpi_disabled)
555 		mbox_free_channel(ctx->mbox_chan);
556 	else
557 		pcc_mbox_free_channel(ctx->mbox_chan);
558 
559 	return rc;
560 }
561 
562 static int xgene_slimpro_i2c_remove(struct platform_device *pdev)
563 {
564 	struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev);
565 
566 	i2c_del_adapter(&ctx->adapter);
567 
568 	if (acpi_disabled)
569 		mbox_free_channel(ctx->mbox_chan);
570 	else
571 		pcc_mbox_free_channel(ctx->mbox_chan);
572 
573 	return 0;
574 }
575 
576 static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = {
577 	{.compatible = "apm,xgene-slimpro-i2c" },
578 	{},
579 };
580 MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids);
581 
582 #ifdef CONFIG_ACPI
583 static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = {
584 	{"APMC0D40", 0},
585 	{}
586 };
587 MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids);
588 #endif
589 
590 static struct platform_driver xgene_slimpro_i2c_driver = {
591 	.probe	= xgene_slimpro_i2c_probe,
592 	.remove	= xgene_slimpro_i2c_remove,
593 	.driver	= {
594 		.name	= "xgene-slimpro-i2c",
595 		.of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids),
596 		.acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids)
597 	},
598 };
599 
600 module_platform_driver(xgene_slimpro_i2c_driver);
601 
602 MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver");
603 MODULE_AUTHOR("Feng Kan <fkan@apm.com>");
604 MODULE_AUTHOR("Hieu Le <hnle@apm.com>");
605 MODULE_LICENSE("GPL");
606