1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/device.h>
4 #include <linux/err.h>
5 #include <linux/errno.h>
6 #include <linux/fs.h>
7 #include <linux/fsi-sbefifo.h>
8 #include <linux/gfp.h>
9 #include <linux/idr.h>
10 #include <linux/kernel.h>
11 #include <linux/list.h>
12 #include <linux/miscdevice.h>
13 #include <linux/mm.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/fsi-occ.h>
17 #include <linux/of.h>
18 #include <linux/of_device.h>
19 #include <linux/platform_device.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/uaccess.h>
23 #include <asm/unaligned.h>
24 
25 #define OCC_SRAM_BYTES		4096
26 #define OCC_CMD_DATA_BYTES	4090
27 #define OCC_RESP_DATA_BYTES	4089
28 
29 #define OCC_P9_SRAM_CMD_ADDR	0xFFFBE000
30 #define OCC_P9_SRAM_RSP_ADDR	0xFFFBF000
31 
32 #define OCC_P10_SRAM_CMD_ADDR	0xFFFFD000
33 #define OCC_P10_SRAM_RSP_ADDR	0xFFFFE000
34 
35 #define OCC_P10_SRAM_MODE	0x58	/* Normal mode, OCB channel 2 */
36 
37 #define OCC_TIMEOUT_MS		1000
38 #define OCC_CMD_IN_PRG_WAIT_MS	50
39 
40 enum versions { occ_p9, occ_p10 };
41 
42 struct occ {
43 	struct device *dev;
44 	struct device *sbefifo;
45 	char name[32];
46 	int idx;
47 	u8 sequence_number;
48 	void *buffer;
49 	void *client_buffer;
50 	size_t client_buffer_size;
51 	size_t client_response_size;
52 	enum versions version;
53 	struct miscdevice mdev;
54 	struct mutex occ_lock;
55 };
56 
57 #define to_occ(x)	container_of((x), struct occ, mdev)
58 
59 struct occ_response {
60 	u8 seq_no;
61 	u8 cmd_type;
62 	u8 return_status;
63 	__be16 data_length;
64 	u8 data[OCC_RESP_DATA_BYTES + 2];	/* two bytes checksum */
65 } __packed;
66 
67 struct occ_client {
68 	struct occ *occ;
69 	struct mutex lock;
70 	size_t data_size;
71 	size_t read_offset;
72 	u8 *buffer;
73 };
74 
75 #define to_client(x)	container_of((x), struct occ_client, xfr)
76 
77 static DEFINE_IDA(occ_ida);
78 
occ_open(struct inode * inode,struct file * file)79 static int occ_open(struct inode *inode, struct file *file)
80 {
81 	struct occ_client *client = kzalloc(sizeof(*client), GFP_KERNEL);
82 	struct miscdevice *mdev = file->private_data;
83 	struct occ *occ = to_occ(mdev);
84 
85 	if (!client)
86 		return -ENOMEM;
87 
88 	client->buffer = (u8 *)__get_free_page(GFP_KERNEL);
89 	if (!client->buffer) {
90 		kfree(client);
91 		return -ENOMEM;
92 	}
93 
94 	client->occ = occ;
95 	mutex_init(&client->lock);
96 	file->private_data = client;
97 
98 	/* We allocate a 1-page buffer, make sure it all fits */
99 	BUILD_BUG_ON((OCC_CMD_DATA_BYTES + 3) > PAGE_SIZE);
100 	BUILD_BUG_ON((OCC_RESP_DATA_BYTES + 7) > PAGE_SIZE);
101 
102 	return 0;
103 }
104 
occ_read(struct file * file,char __user * buf,size_t len,loff_t * offset)105 static ssize_t occ_read(struct file *file, char __user *buf, size_t len,
106 			loff_t *offset)
107 {
108 	struct occ_client *client = file->private_data;
109 	ssize_t rc = 0;
110 
111 	if (!client)
112 		return -ENODEV;
113 
114 	if (len > OCC_SRAM_BYTES)
115 		return -EINVAL;
116 
117 	mutex_lock(&client->lock);
118 
119 	/* This should not be possible ... */
120 	if (WARN_ON_ONCE(client->read_offset > client->data_size)) {
121 		rc = -EIO;
122 		goto done;
123 	}
124 
125 	/* Grab how much data we have to read */
126 	rc = min(len, client->data_size - client->read_offset);
127 	if (copy_to_user(buf, client->buffer + client->read_offset, rc))
128 		rc = -EFAULT;
129 	else
130 		client->read_offset += rc;
131 
132  done:
133 	mutex_unlock(&client->lock);
134 
135 	return rc;
136 }
137 
occ_write(struct file * file,const char __user * buf,size_t len,loff_t * offset)138 static ssize_t occ_write(struct file *file, const char __user *buf,
139 			 size_t len, loff_t *offset)
140 {
141 	struct occ_client *client = file->private_data;
142 	size_t rlen, data_length;
143 	ssize_t rc;
144 	u8 *cmd;
145 
146 	if (!client)
147 		return -ENODEV;
148 
149 	if (len > (OCC_CMD_DATA_BYTES + 3) || len < 3)
150 		return -EINVAL;
151 
152 	mutex_lock(&client->lock);
153 
154 	/* Construct the command */
155 	cmd = client->buffer;
156 
157 	/*
158 	 * Copy the user command (assume user data follows the occ command
159 	 * format)
160 	 * byte 0: command type
161 	 * bytes 1-2: data length (msb first)
162 	 * bytes 3-n: data
163 	 */
164 	if (copy_from_user(&cmd[1], buf, len)) {
165 		rc = -EFAULT;
166 		goto done;
167 	}
168 
169 	/* Extract data length */
170 	data_length = (cmd[2] << 8) + cmd[3];
171 	if (data_length > OCC_CMD_DATA_BYTES) {
172 		rc = -EINVAL;
173 		goto done;
174 	}
175 
176 	/* Submit command; 4 bytes before the data and 2 bytes after */
177 	rlen = PAGE_SIZE;
178 	rc = fsi_occ_submit(client->occ->dev, cmd, data_length + 6, cmd,
179 			    &rlen);
180 	if (rc)
181 		goto done;
182 
183 	/* Set read tracking data */
184 	client->data_size = rlen;
185 	client->read_offset = 0;
186 
187 	/* Done */
188 	rc = len;
189 
190  done:
191 	mutex_unlock(&client->lock);
192 
193 	return rc;
194 }
195 
occ_release(struct inode * inode,struct file * file)196 static int occ_release(struct inode *inode, struct file *file)
197 {
198 	struct occ_client *client = file->private_data;
199 
200 	free_page((unsigned long)client->buffer);
201 	kfree(client);
202 
203 	return 0;
204 }
205 
206 static const struct file_operations occ_fops = {
207 	.owner = THIS_MODULE,
208 	.open = occ_open,
209 	.read = occ_read,
210 	.write = occ_write,
211 	.release = occ_release,
212 };
213 
occ_save_ffdc(struct occ * occ,__be32 * resp,size_t parsed_len,size_t resp_len)214 static void occ_save_ffdc(struct occ *occ, __be32 *resp, size_t parsed_len,
215 			  size_t resp_len)
216 {
217 	if (resp_len > parsed_len) {
218 		size_t dh = resp_len - parsed_len;
219 		size_t ffdc_len = (dh - 1) * 4; /* SBE words are four bytes */
220 		__be32 *ffdc = &resp[parsed_len];
221 
222 		if (ffdc_len > occ->client_buffer_size)
223 			ffdc_len = occ->client_buffer_size;
224 
225 		memcpy(occ->client_buffer, ffdc, ffdc_len);
226 		occ->client_response_size = ffdc_len;
227 	}
228 }
229 
occ_verify_checksum(struct occ * occ,struct occ_response * resp,u16 data_length)230 static int occ_verify_checksum(struct occ *occ, struct occ_response *resp,
231 			       u16 data_length)
232 {
233 	/* Fetch the two bytes after the data for the checksum. */
234 	u16 checksum_resp = get_unaligned_be16(&resp->data[data_length]);
235 	u16 checksum;
236 	u16 i;
237 
238 	checksum = resp->seq_no;
239 	checksum += resp->cmd_type;
240 	checksum += resp->return_status;
241 	checksum += (data_length >> 8) + (data_length & 0xFF);
242 
243 	for (i = 0; i < data_length; ++i)
244 		checksum += resp->data[i];
245 
246 	if (checksum != checksum_resp) {
247 		dev_err(occ->dev, "Bad checksum: %04x!=%04x\n", checksum,
248 			checksum_resp);
249 		return -EBADMSG;
250 	}
251 
252 	return 0;
253 }
254 
occ_getsram(struct occ * occ,u32 offset,void * data,ssize_t len)255 static int occ_getsram(struct occ *occ, u32 offset, void *data, ssize_t len)
256 {
257 	u32 data_len = ((len + 7) / 8) * 8;	/* must be multiples of 8 B */
258 	size_t cmd_len, parsed_len, resp_data_len;
259 	size_t resp_len = OCC_MAX_RESP_WORDS;
260 	__be32 *resp = occ->buffer;
261 	__be32 cmd[6];
262 	int idx = 0, rc;
263 
264 	/*
265 	 * Magic sequence to do SBE getsram command. SBE will fetch data from
266 	 * specified SRAM address.
267 	 */
268 	switch (occ->version) {
269 	default:
270 	case occ_p9:
271 		cmd_len = 5;
272 		cmd[2] = cpu_to_be32(1);	/* Normal mode */
273 		cmd[3] = cpu_to_be32(OCC_P9_SRAM_RSP_ADDR + offset);
274 		break;
275 	case occ_p10:
276 		idx = 1;
277 		cmd_len = 6;
278 		cmd[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
279 		cmd[3] = 0;
280 		cmd[4] = cpu_to_be32(OCC_P10_SRAM_RSP_ADDR + offset);
281 		break;
282 	}
283 
284 	cmd[0] = cpu_to_be32(cmd_len);
285 	cmd[1] = cpu_to_be32(SBEFIFO_CMD_GET_OCC_SRAM);
286 	cmd[4 + idx] = cpu_to_be32(data_len);
287 
288 	rc = sbefifo_submit(occ->sbefifo, cmd, cmd_len, resp, &resp_len);
289 	if (rc)
290 		return rc;
291 
292 	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_GET_OCC_SRAM,
293 				  resp, resp_len, &parsed_len);
294 	if (rc > 0) {
295 		dev_err(occ->dev, "SRAM read returned failure status: %08x\n",
296 			rc);
297 		occ_save_ffdc(occ, resp, parsed_len, resp_len);
298 		return -ECOMM;
299 	} else if (rc) {
300 		return rc;
301 	}
302 
303 	resp_data_len = be32_to_cpu(resp[parsed_len - 1]);
304 	if (resp_data_len != data_len) {
305 		dev_err(occ->dev, "SRAM read expected %d bytes got %zd\n",
306 			data_len, resp_data_len);
307 		rc = -EBADMSG;
308 	} else {
309 		memcpy(data, resp, len);
310 	}
311 
312 	return rc;
313 }
314 
occ_putsram(struct occ * occ,const void * data,ssize_t len,u8 seq_no,u16 checksum)315 static int occ_putsram(struct occ *occ, const void *data, ssize_t len,
316 		       u8 seq_no, u16 checksum)
317 {
318 	u32 data_len = ((len + 7) / 8) * 8;	/* must be multiples of 8 B */
319 	size_t cmd_len, parsed_len, resp_data_len;
320 	size_t resp_len = OCC_MAX_RESP_WORDS;
321 	__be32 *buf = occ->buffer;
322 	u8 *byte_buf;
323 	int idx = 0, rc;
324 
325 	cmd_len = (occ->version == occ_p10) ? 6 : 5;
326 	cmd_len += data_len >> 2;
327 
328 	/*
329 	 * Magic sequence to do SBE putsram command. SBE will transfer
330 	 * data to specified SRAM address.
331 	 */
332 	buf[0] = cpu_to_be32(cmd_len);
333 	buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
334 
335 	switch (occ->version) {
336 	default:
337 	case occ_p9:
338 		buf[2] = cpu_to_be32(1);	/* Normal mode */
339 		buf[3] = cpu_to_be32(OCC_P9_SRAM_CMD_ADDR);
340 		break;
341 	case occ_p10:
342 		idx = 1;
343 		buf[2] = cpu_to_be32(OCC_P10_SRAM_MODE);
344 		buf[3] = 0;
345 		buf[4] = cpu_to_be32(OCC_P10_SRAM_CMD_ADDR);
346 		break;
347 	}
348 
349 	buf[4 + idx] = cpu_to_be32(data_len);
350 	memcpy(&buf[5 + idx], data, len);
351 
352 	byte_buf = (u8 *)&buf[5 + idx];
353 	/*
354 	 * Overwrite the first byte with our sequence number and the last two
355 	 * bytes with the checksum.
356 	 */
357 	byte_buf[0] = seq_no;
358 	byte_buf[len - 2] = checksum >> 8;
359 	byte_buf[len - 1] = checksum & 0xff;
360 
361 	rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
362 	if (rc)
363 		return rc;
364 
365 	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
366 				  buf, resp_len, &parsed_len);
367 	if (rc > 0) {
368 		dev_err(occ->dev, "SRAM write returned failure status: %08x\n",
369 			rc);
370 		occ_save_ffdc(occ, buf, parsed_len, resp_len);
371 		return -ECOMM;
372 	} else if (rc) {
373 		return rc;
374 	}
375 
376 	if (parsed_len != 1) {
377 		dev_err(occ->dev, "SRAM write response length invalid: %zd\n",
378 			parsed_len);
379 		rc = -EBADMSG;
380 	} else {
381 		resp_data_len = be32_to_cpu(buf[0]);
382 		if (resp_data_len != data_len) {
383 			dev_err(occ->dev,
384 				"SRAM write expected %d bytes got %zd\n",
385 				data_len, resp_data_len);
386 			rc = -EBADMSG;
387 		}
388 	}
389 
390 	return rc;
391 }
392 
occ_trigger_attn(struct occ * occ)393 static int occ_trigger_attn(struct occ *occ)
394 {
395 	__be32 *buf = occ->buffer;
396 	size_t cmd_len, parsed_len, resp_data_len;
397 	size_t resp_len = OCC_MAX_RESP_WORDS;
398 	int idx = 0, rc;
399 
400 	switch (occ->version) {
401 	default:
402 	case occ_p9:
403 		cmd_len = 7;
404 		buf[2] = cpu_to_be32(3); /* Circular mode */
405 		buf[3] = 0;
406 		break;
407 	case occ_p10:
408 		idx = 1;
409 		cmd_len = 8;
410 		buf[2] = cpu_to_be32(0xd0); /* Circular mode, OCB Channel 1 */
411 		buf[3] = 0;
412 		buf[4] = 0;
413 		break;
414 	}
415 
416 	buf[0] = cpu_to_be32(cmd_len);		/* Chip-op length in words */
417 	buf[1] = cpu_to_be32(SBEFIFO_CMD_PUT_OCC_SRAM);
418 	buf[4 + idx] = cpu_to_be32(8);		/* Data length in bytes */
419 	buf[5 + idx] = cpu_to_be32(0x20010000);	/* Trigger OCC attention */
420 	buf[6 + idx] = 0;
421 
422 	rc = sbefifo_submit(occ->sbefifo, buf, cmd_len, buf, &resp_len);
423 	if (rc)
424 		return rc;
425 
426 	rc = sbefifo_parse_status(occ->sbefifo, SBEFIFO_CMD_PUT_OCC_SRAM,
427 				  buf, resp_len, &parsed_len);
428 	if (rc > 0) {
429 		dev_err(occ->dev, "SRAM attn returned failure status: %08x\n",
430 			rc);
431 		occ_save_ffdc(occ, buf, parsed_len, resp_len);
432 		return -ECOMM;
433 	} else if (rc) {
434 		return rc;
435 	}
436 
437 	if (parsed_len != 1) {
438 		dev_err(occ->dev, "SRAM attn response length invalid: %zd\n",
439 			parsed_len);
440 		rc = -EBADMSG;
441 	} else {
442 		resp_data_len = be32_to_cpu(buf[0]);
443 		if (resp_data_len != 8) {
444 			dev_err(occ->dev,
445 				"SRAM attn expected 8 bytes got %zd\n",
446 				resp_data_len);
447 			rc = -EBADMSG;
448 		}
449 	}
450 
451 	return rc;
452 }
453 
fsi_occ_response_not_ready(struct occ_response * resp,u8 seq_no,u8 cmd_type)454 static bool fsi_occ_response_not_ready(struct occ_response *resp, u8 seq_no,
455 				       u8 cmd_type)
456 {
457 	return resp->return_status == OCC_RESP_CMD_IN_PRG ||
458 		resp->return_status == OCC_RESP_CRIT_INIT ||
459 		resp->seq_no != seq_no || resp->cmd_type != cmd_type;
460 }
461 
fsi_occ_submit(struct device * dev,const void * request,size_t req_len,void * response,size_t * resp_len)462 int fsi_occ_submit(struct device *dev, const void *request, size_t req_len,
463 		   void *response, size_t *resp_len)
464 {
465 	const unsigned long timeout = msecs_to_jiffies(OCC_TIMEOUT_MS);
466 	const unsigned long wait_time =
467 		msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS);
468 	struct occ *occ = dev_get_drvdata(dev);
469 	struct occ_response *resp = response;
470 	size_t user_resp_len = *resp_len;
471 	u8 seq_no;
472 	u8 cmd_type;
473 	u16 checksum = 0;
474 	u16 resp_data_length;
475 	const u8 *byte_request = (const u8 *)request;
476 	unsigned long end;
477 	int rc;
478 	size_t i;
479 
480 	*resp_len = 0;
481 
482 	if (!occ)
483 		return -ENODEV;
484 
485 	if (user_resp_len < 7) {
486 		dev_dbg(dev, "Bad resplen %zd\n", user_resp_len);
487 		return -EINVAL;
488 	}
489 
490 	cmd_type = byte_request[1];
491 
492 	/* Checksum the request, ignoring first byte (sequence number). */
493 	for (i = 1; i < req_len - 2; ++i)
494 		checksum += byte_request[i];
495 
496 	mutex_lock(&occ->occ_lock);
497 
498 	occ->client_buffer = response;
499 	occ->client_buffer_size = user_resp_len;
500 	occ->client_response_size = 0;
501 
502 	/*
503 	 * Get a sequence number and update the counter. Avoid a sequence
504 	 * number of 0 which would pass the response check below even if the
505 	 * OCC response is uninitialized. Any sequence number the user is
506 	 * trying to send is overwritten since this function is the only common
507 	 * interface to the OCC and therefore the only place we can guarantee
508 	 * unique sequence numbers.
509 	 */
510 	seq_no = occ->sequence_number++;
511 	if (!occ->sequence_number)
512 		occ->sequence_number = 1;
513 	checksum += seq_no;
514 
515 	rc = occ_putsram(occ, request, req_len, seq_no, checksum);
516 	if (rc)
517 		goto done;
518 
519 	rc = occ_trigger_attn(occ);
520 	if (rc)
521 		goto done;
522 
523 	end = jiffies + timeout;
524 	while (true) {
525 		/* Read occ response header */
526 		rc = occ_getsram(occ, 0, resp, 8);
527 		if (rc)
528 			goto done;
529 
530 		if (fsi_occ_response_not_ready(resp, seq_no, cmd_type)) {
531 			if (time_after(jiffies, end)) {
532 				dev_err(occ->dev,
533 					"resp timeout status=%02x seq=%d cmd=%d, our seq=%d cmd=%d\n",
534 					resp->return_status, resp->seq_no,
535 					resp->cmd_type, seq_no, cmd_type);
536 				rc = -ETIMEDOUT;
537 				goto done;
538 			}
539 
540 			set_current_state(TASK_UNINTERRUPTIBLE);
541 			schedule_timeout(wait_time);
542 		} else {
543 			/* Extract size of response data */
544 			resp_data_length =
545 				get_unaligned_be16(&resp->data_length);
546 
547 			/*
548 			 * Message size is data length + 5 bytes header + 2
549 			 * bytes checksum
550 			 */
551 			if ((resp_data_length + 7) > user_resp_len) {
552 				rc = -EMSGSIZE;
553 				goto done;
554 			}
555 
556 			/*
557 			 * Get the entire response including the header again,
558 			 * in case it changed
559 			 */
560 			if (resp_data_length > 1) {
561 				rc = occ_getsram(occ, 0, resp,
562 						 resp_data_length + 7);
563 				if (rc)
564 					goto done;
565 
566 				if (!fsi_occ_response_not_ready(resp, seq_no,
567 								cmd_type))
568 					break;
569 			} else {
570 				break;
571 			}
572 		}
573 	}
574 
575 	dev_dbg(dev, "resp_status=%02x resp_data_len=%d\n",
576 		resp->return_status, resp_data_length);
577 
578 	occ->client_response_size = resp_data_length + 7;
579 	rc = occ_verify_checksum(occ, resp, resp_data_length);
580 
581  done:
582 	*resp_len = occ->client_response_size;
583 	mutex_unlock(&occ->occ_lock);
584 
585 	return rc;
586 }
587 EXPORT_SYMBOL_GPL(fsi_occ_submit);
588 
occ_unregister_child(struct device * dev,void * data)589 static int occ_unregister_child(struct device *dev, void *data)
590 {
591 	struct platform_device *hwmon_dev = to_platform_device(dev);
592 
593 	platform_device_unregister(hwmon_dev);
594 
595 	return 0;
596 }
597 
occ_probe(struct platform_device * pdev)598 static int occ_probe(struct platform_device *pdev)
599 {
600 	int rc;
601 	u32 reg;
602 	struct occ *occ;
603 	struct platform_device *hwmon_dev;
604 	struct device *dev = &pdev->dev;
605 	struct platform_device_info hwmon_dev_info = {
606 		.parent = dev,
607 		.name = "occ-hwmon",
608 	};
609 
610 	occ = devm_kzalloc(dev, sizeof(*occ), GFP_KERNEL);
611 	if (!occ)
612 		return -ENOMEM;
613 
614 	/* SBE words are always four bytes */
615 	occ->buffer = kvmalloc(OCC_MAX_RESP_WORDS * 4, GFP_KERNEL);
616 	if (!occ->buffer)
617 		return -ENOMEM;
618 
619 	occ->version = (uintptr_t)of_device_get_match_data(dev);
620 	occ->dev = dev;
621 	occ->sbefifo = dev->parent;
622 	/*
623 	 * Quickly derive a pseudo-random number from jiffies so that
624 	 * re-probing the driver doesn't accidentally overlap sequence numbers.
625 	 */
626 	occ->sequence_number = (u8)((jiffies % 0xff) + 1);
627 	mutex_init(&occ->occ_lock);
628 
629 	if (dev->of_node) {
630 		rc = of_property_read_u32(dev->of_node, "reg", &reg);
631 		if (!rc) {
632 			/* make sure we don't have a duplicate from dts */
633 			occ->idx = ida_simple_get(&occ_ida, reg, reg + 1,
634 						  GFP_KERNEL);
635 			if (occ->idx < 0)
636 				occ->idx = ida_simple_get(&occ_ida, 1, INT_MAX,
637 							  GFP_KERNEL);
638 		} else {
639 			occ->idx = ida_simple_get(&occ_ida, 1, INT_MAX,
640 						  GFP_KERNEL);
641 		}
642 	} else {
643 		occ->idx = ida_simple_get(&occ_ida, 1, INT_MAX, GFP_KERNEL);
644 	}
645 
646 	platform_set_drvdata(pdev, occ);
647 
648 	snprintf(occ->name, sizeof(occ->name), "occ%d", occ->idx);
649 	occ->mdev.fops = &occ_fops;
650 	occ->mdev.minor = MISC_DYNAMIC_MINOR;
651 	occ->mdev.name = occ->name;
652 	occ->mdev.parent = dev;
653 
654 	rc = misc_register(&occ->mdev);
655 	if (rc) {
656 		dev_err(dev, "failed to register miscdevice: %d\n", rc);
657 		ida_simple_remove(&occ_ida, occ->idx);
658 		kvfree(occ->buffer);
659 		return rc;
660 	}
661 
662 	hwmon_dev_info.id = occ->idx;
663 	hwmon_dev = platform_device_register_full(&hwmon_dev_info);
664 	if (IS_ERR(hwmon_dev))
665 		dev_warn(dev, "failed to create hwmon device\n");
666 
667 	return 0;
668 }
669 
occ_remove(struct platform_device * pdev)670 static int occ_remove(struct platform_device *pdev)
671 {
672 	struct occ *occ = platform_get_drvdata(pdev);
673 
674 	kvfree(occ->buffer);
675 
676 	misc_deregister(&occ->mdev);
677 
678 	device_for_each_child(&pdev->dev, NULL, occ_unregister_child);
679 
680 	ida_simple_remove(&occ_ida, occ->idx);
681 
682 	return 0;
683 }
684 
685 static const struct of_device_id occ_match[] = {
686 	{
687 		.compatible = "ibm,p9-occ",
688 		.data = (void *)occ_p9
689 	},
690 	{
691 		.compatible = "ibm,p10-occ",
692 		.data = (void *)occ_p10
693 	},
694 	{ },
695 };
696 MODULE_DEVICE_TABLE(of, occ_match);
697 
698 static struct platform_driver occ_driver = {
699 	.driver = {
700 		.name = "occ",
701 		.of_match_table	= occ_match,
702 	},
703 	.probe	= occ_probe,
704 	.remove = occ_remove,
705 };
706 
occ_init(void)707 static int occ_init(void)
708 {
709 	return platform_driver_register(&occ_driver);
710 }
711 
occ_exit(void)712 static void occ_exit(void)
713 {
714 	platform_driver_unregister(&occ_driver);
715 
716 	ida_destroy(&occ_ida);
717 }
718 
719 module_init(occ_init);
720 module_exit(occ_exit);
721 
722 MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
723 MODULE_DESCRIPTION("BMC P9 OCC driver");
724 MODULE_LICENSE("GPL");
725