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  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Copyright 2017 IBM Corp.
  4 */
  5
  6#include <linux/bitfield.h>
  7#include <linux/bitops.h>
  8#include <linux/debugfs.h>
  9#include <linux/device.h>
 10#include <linux/fs.h>
 11#include <linux/i2c.h>
 12#include <linux/jiffies.h>
 13#include <linux/leds.h>
 14#include <linux/module.h>
 15#include <linux/mutex.h>
 16#include <linux/of_device.h>
 17#include <linux/pmbus.h>
 18
 19#include "pmbus.h"
 20
 21#define CFFPS_FRU_CMD				0x9A
 22#define CFFPS_PN_CMD				0x9B
 23#define CFFPS_HEADER_CMD			0x9C
 24#define CFFPS_SN_CMD				0x9E
 25#define CFFPS_MAX_POWER_OUT_CMD			0xA7
 26#define CFFPS_CCIN_CMD				0xBD
 27#define CFFPS_FW_CMD				0xFA
 28#define CFFPS1_FW_NUM_BYTES			4
 29#define CFFPS2_FW_NUM_WORDS			3
 30#define CFFPS_SYS_CONFIG_CMD			0xDA
 31#define CFFPS_12VCS_VOUT_CMD			0xDE
 32
 33#define CFFPS_INPUT_HISTORY_CMD			0xD6
 34#define CFFPS_INPUT_HISTORY_SIZE		100
 35
 36#define CFFPS_CCIN_REVISION			GENMASK(7, 0)
 37#define  CFFPS_CCIN_REVISION_LEGACY		 0xde
 38#define CFFPS_CCIN_VERSION			GENMASK(15, 8)
 39#define CFFPS_CCIN_VERSION_1			 0x2b
 40#define CFFPS_CCIN_VERSION_2			 0x2e
 41#define CFFPS_CCIN_VERSION_3			 0x51
 42
 43/* STATUS_MFR_SPECIFIC bits */
 44#define CFFPS_MFR_FAN_FAULT			BIT(0)
 45#define CFFPS_MFR_THERMAL_FAULT			BIT(1)
 46#define CFFPS_MFR_OV_FAULT			BIT(2)
 47#define CFFPS_MFR_UV_FAULT			BIT(3)
 48#define CFFPS_MFR_PS_KILL			BIT(4)
 49#define CFFPS_MFR_OC_FAULT			BIT(5)
 50#define CFFPS_MFR_VAUX_FAULT			BIT(6)
 51#define CFFPS_MFR_CURRENT_SHARE_WARNING		BIT(7)
 52
 53#define CFFPS_LED_BLINK				(BIT(0) | BIT(6))
 54#define CFFPS_LED_ON				(BIT(1) | BIT(6))
 55#define CFFPS_LED_OFF				(BIT(2) | BIT(6))
 56#define CFFPS_BLINK_RATE_MS			250
 57
 58enum {
 59	CFFPS_DEBUGFS_INPUT_HISTORY = 0,
 60	CFFPS_DEBUGFS_FRU,
 61	CFFPS_DEBUGFS_PN,
 62	CFFPS_DEBUGFS_HEADER,
 63	CFFPS_DEBUGFS_SN,
 64	CFFPS_DEBUGFS_MAX_POWER_OUT,
 65	CFFPS_DEBUGFS_CCIN,
 66	CFFPS_DEBUGFS_FW,
 67	CFFPS_DEBUGFS_ON_OFF_CONFIG,
 68	CFFPS_DEBUGFS_NUM_ENTRIES
 69};
 70
 71enum versions { cffps1, cffps2, cffps_unknown };
 72
 73struct ibm_cffps_input_history {
 74	struct mutex update_lock;
 75	unsigned long last_update;
 76
 77	u8 byte_count;
 78	u8 data[CFFPS_INPUT_HISTORY_SIZE];
 79};
 80
 81struct ibm_cffps {
 82	enum versions version;
 83	struct i2c_client *client;
 84
 85	struct ibm_cffps_input_history input_history;
 86
 87	int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
 88
 89	char led_name[32];
 90	u8 led_state;
 91	struct led_classdev led;
 92};
 93
 94static const struct i2c_device_id ibm_cffps_id[];
 95
 96#define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
 97
 98static ssize_t ibm_cffps_read_input_history(struct ibm_cffps *psu,
 99					    char __user *buf, size_t count,
100					    loff_t *ppos)
101{
102	int rc;
103	u8 msgbuf0[1] = { CFFPS_INPUT_HISTORY_CMD };
104	u8 msgbuf1[CFFPS_INPUT_HISTORY_SIZE + 1] = { 0 };
105	struct i2c_msg msg[2] = {
106		{
107			.addr = psu->client->addr,
108			.flags = psu->client->flags,
109			.len = 1,
110			.buf = msgbuf0,
111		}, {
112			.addr = psu->client->addr,
113			.flags = psu->client->flags | I2C_M_RD,
114			.len = CFFPS_INPUT_HISTORY_SIZE + 1,
115			.buf = msgbuf1,
116		},
117	};
118
119	if (!*ppos) {
120		mutex_lock(&psu->input_history.update_lock);
121		if (time_after(jiffies, psu->input_history.last_update + HZ)) {
122			/*
123			 * Use a raw i2c transfer, since we need more bytes
124			 * than Linux I2C supports through smbus xfr (only 32).
125			 */
126			rc = i2c_transfer(psu->client->adapter, msg, 2);
127			if (rc < 0) {
128				mutex_unlock(&psu->input_history.update_lock);
129				return rc;
130			}
131
132			psu->input_history.byte_count = msgbuf1[0];
133			memcpy(psu->input_history.data, &msgbuf1[1],
134			       CFFPS_INPUT_HISTORY_SIZE);
135			psu->input_history.last_update = jiffies;
136		}
137
138		mutex_unlock(&psu->input_history.update_lock);
139	}
140
141	return simple_read_from_buffer(buf, count, ppos,
142				       psu->input_history.data,
143				       psu->input_history.byte_count);
144}
145
146static ssize_t ibm_cffps_debugfs_read(struct file *file, char __user *buf,
147				      size_t count, loff_t *ppos)
148{
149	u8 cmd;
150	int i, rc;
151	int *idxp = file->private_data;
152	int idx = *idxp;
153	struct ibm_cffps *psu = to_psu(idxp, idx);
154	char data[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
155
156	pmbus_set_page(psu->client, 0, 0xff);
157
158	switch (idx) {
159	case CFFPS_DEBUGFS_INPUT_HISTORY:
160		return ibm_cffps_read_input_history(psu, buf, count, ppos);
161	case CFFPS_DEBUGFS_FRU:
162		cmd = CFFPS_FRU_CMD;
163		break;
164	case CFFPS_DEBUGFS_PN:
165		cmd = CFFPS_PN_CMD;
166		break;
167	case CFFPS_DEBUGFS_HEADER:
168		cmd = CFFPS_HEADER_CMD;
169		break;
170	case CFFPS_DEBUGFS_SN:
171		cmd = CFFPS_SN_CMD;
172		break;
173	case CFFPS_DEBUGFS_MAX_POWER_OUT:
174		if (psu->version == cffps1) {
175			rc = i2c_smbus_read_word_swapped(psu->client,
176					CFFPS_MAX_POWER_OUT_CMD);
177		} else {
178			rc = i2c_smbus_read_word_data(psu->client,
179					CFFPS_MAX_POWER_OUT_CMD);
180		}
181
182		if (rc < 0)
183			return rc;
184
185		rc = snprintf(data, I2C_SMBUS_BLOCK_MAX, "%d", rc);
186		goto done;
187	case CFFPS_DEBUGFS_CCIN:
188		rc = i2c_smbus_read_word_swapped(psu->client, CFFPS_CCIN_CMD);
189		if (rc < 0)
190			return rc;
191
192		rc = snprintf(data, 5, "%04X", rc);
193		goto done;
194	case CFFPS_DEBUGFS_FW:
195		switch (psu->version) {
196		case cffps1:
197			for (i = 0; i < CFFPS1_FW_NUM_BYTES; ++i) {
198				rc = i2c_smbus_read_byte_data(psu->client,
199							      CFFPS_FW_CMD +
200								i);
201				if (rc < 0)
202					return rc;
203
204				snprintf(&data[i * 2], 3, "%02X", rc);
205			}
206
207			rc = i * 2;
208			break;
209		case cffps2:
210			for (i = 0; i < CFFPS2_FW_NUM_WORDS; ++i) {
211				rc = i2c_smbus_read_word_data(psu->client,
212							      CFFPS_FW_CMD +
213								i);
214				if (rc < 0)
215					return rc;
216
217				snprintf(&data[i * 4], 5, "%04X", rc);
218			}
219
220			rc = i * 4;
221			break;
222		default:
223			return -EOPNOTSUPP;
224		}
225		goto done;
226	case CFFPS_DEBUGFS_ON_OFF_CONFIG:
227		rc = i2c_smbus_read_byte_data(psu->client,
228					      PMBUS_ON_OFF_CONFIG);
229		if (rc < 0)
230			return rc;
231
232		rc = snprintf(data, 3, "%02x", rc);
233		goto done;
234	default:
235		return -EINVAL;
236	}
237
238	rc = i2c_smbus_read_block_data(psu->client, cmd, data);
239	if (rc < 0)
240		return rc;
241
242done:
243	data[rc] = '\n';
244	rc += 2;
245
246	return simple_read_from_buffer(buf, count, ppos, data, rc);
247}
248
249static ssize_t ibm_cffps_debugfs_write(struct file *file,
250				       const char __user *buf, size_t count,
251				       loff_t *ppos)
252{
253	u8 data;
254	ssize_t rc;
255	int *idxp = file->private_data;
256	int idx = *idxp;
257	struct ibm_cffps *psu = to_psu(idxp, idx);
258
259	switch (idx) {
260	case CFFPS_DEBUGFS_ON_OFF_CONFIG:
261		pmbus_set_page(psu->client, 0, 0xff);
262
263		rc = simple_write_to_buffer(&data, 1, ppos, buf, count);
264		if (rc <= 0)
265			return rc;
266
267		rc = i2c_smbus_write_byte_data(psu->client,
268					       PMBUS_ON_OFF_CONFIG, data);
269		if (rc)
270			return rc;
271
272		rc = 1;
273		break;
274	default:
275		return -EINVAL;
276	}
277
278	return rc;
279}
280
281static const struct file_operations ibm_cffps_fops = {
282	.llseek = noop_llseek,
283	.read = ibm_cffps_debugfs_read,
284	.write = ibm_cffps_debugfs_write,
285	.open = simple_open,
286};
287
288static int ibm_cffps_read_byte_data(struct i2c_client *client, int page,
289				    int reg)
290{
291	int rc, mfr;
292
293	switch (reg) {
294	case PMBUS_STATUS_VOUT:
295	case PMBUS_STATUS_IOUT:
296	case PMBUS_STATUS_TEMPERATURE:
297	case PMBUS_STATUS_FAN_12:
298		rc = pmbus_read_byte_data(client, page, reg);
299		if (rc < 0)
300			return rc;
301
302		mfr = pmbus_read_byte_data(client, page,
303					   PMBUS_STATUS_MFR_SPECIFIC);
304		if (mfr < 0)
305			/*
306			 * Return the status register instead of an error,
307			 * since we successfully read status.
308			 */
309			return rc;
310
311		/* Add MFR_SPECIFIC bits to the standard pmbus status regs. */
312		if (reg == PMBUS_STATUS_FAN_12) {
313			if (mfr & CFFPS_MFR_FAN_FAULT)
314				rc |= PB_FAN_FAN1_FAULT;
315		} else if (reg == PMBUS_STATUS_TEMPERATURE) {
316			if (mfr & CFFPS_MFR_THERMAL_FAULT)
317				rc |= PB_TEMP_OT_FAULT;
318		} else if (reg == PMBUS_STATUS_VOUT) {
319			if (mfr & (CFFPS_MFR_OV_FAULT | CFFPS_MFR_VAUX_FAULT))
320				rc |= PB_VOLTAGE_OV_FAULT;
321			if (mfr & CFFPS_MFR_UV_FAULT)
322				rc |= PB_VOLTAGE_UV_FAULT;
323		} else if (reg == PMBUS_STATUS_IOUT) {
324			if (mfr & CFFPS_MFR_OC_FAULT)
325				rc |= PB_IOUT_OC_FAULT;
326			if (mfr & CFFPS_MFR_CURRENT_SHARE_WARNING)
327				rc |= PB_CURRENT_SHARE_FAULT;
328		}
329		break;
330	default:
331		rc = -ENODATA;
332		break;
333	}
334
335	return rc;
336}
337
338static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
339				    int phase, int reg)
340{
341	int rc, mfr;
342
343	switch (reg) {
344	case PMBUS_STATUS_WORD:
345		rc = pmbus_read_word_data(client, page, phase, reg);
346		if (rc < 0)
347			return rc;
348
349		mfr = pmbus_read_byte_data(client, page,
350					   PMBUS_STATUS_MFR_SPECIFIC);
351		if (mfr < 0)
352			/*
353			 * Return the status register instead of an error,
354			 * since we successfully read status.
355			 */
356			return rc;
357
358		if (mfr & CFFPS_MFR_PS_KILL)
359			rc |= PB_STATUS_OFF;
360		break;
361	case PMBUS_VIRT_READ_VMON:
362		rc = pmbus_read_word_data(client, page, phase,
363					  CFFPS_12VCS_VOUT_CMD);
364		break;
365	default:
366		rc = -ENODATA;
367		break;
368	}
369
370	return rc;
371}
372
373static int ibm_cffps_led_brightness_set(struct led_classdev *led_cdev,
374					enum led_brightness brightness)
375{
376	int rc;
377	u8 next_led_state;
378	struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
379
380	if (brightness == LED_OFF) {
381		next_led_state = CFFPS_LED_OFF;
382	} else {
383		brightness = LED_FULL;
384
385		if (psu->led_state != CFFPS_LED_BLINK)
386			next_led_state = CFFPS_LED_ON;
387		else
388			next_led_state = CFFPS_LED_BLINK;
389	}
390
391	dev_dbg(&psu->client->dev, "LED brightness set: %d. Command: %d.\n",
392		brightness, next_led_state);
393
394	pmbus_set_page(psu->client, 0, 0xff);
395
396	rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
397				       next_led_state);
398	if (rc < 0)
399		return rc;
400
401	psu->led_state = next_led_state;
402	led_cdev->brightness = brightness;
403
404	return 0;
405}
406
407static int ibm_cffps_led_blink_set(struct led_classdev *led_cdev,
408				   unsigned long *delay_on,
409				   unsigned long *delay_off)
410{
411	int rc;
412	struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
413
414	dev_dbg(&psu->client->dev, "LED blink set.\n");
415
416	pmbus_set_page(psu->client, 0, 0xff);
417
418	rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
419				       CFFPS_LED_BLINK);
420	if (rc < 0)
421		return rc;
422
423	psu->led_state = CFFPS_LED_BLINK;
424	led_cdev->brightness = LED_FULL;
425	*delay_on = CFFPS_BLINK_RATE_MS;
426	*delay_off = CFFPS_BLINK_RATE_MS;
427
428	return 0;
429}
430
431static void ibm_cffps_create_led_class(struct ibm_cffps *psu)
432{
433	int rc;
434	struct i2c_client *client = psu->client;
435	struct device *dev = &client->dev;
436
437	snprintf(psu->led_name, sizeof(psu->led_name), "%s-%02x", client->name,
438		 client->addr);
439	psu->led.name = psu->led_name;
440	psu->led.max_brightness = LED_FULL;
441	psu->led.brightness_set_blocking = ibm_cffps_led_brightness_set;
442	psu->led.blink_set = ibm_cffps_led_blink_set;
443
444	rc = devm_led_classdev_register(dev, &psu->led);
445	if (rc)
446		dev_warn(dev, "failed to register led class: %d\n", rc);
447	else
448		i2c_smbus_write_byte_data(client, CFFPS_SYS_CONFIG_CMD,
449					  CFFPS_LED_OFF);
450}
451
452static struct pmbus_driver_info ibm_cffps_info[] = {
453	[cffps1] = {
454		.pages = 1,
455		.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
456			PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
457			PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
458			PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
459			PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
460			PMBUS_HAVE_STATUS_FAN12,
461		.read_byte_data = ibm_cffps_read_byte_data,
462		.read_word_data = ibm_cffps_read_word_data,
463	},
464	[cffps2] = {
465		.pages = 2,
466		.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
467			PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
468			PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
469			PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
470			PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
471			PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_VMON,
472		.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
473			PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
474			PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT,
475		.read_byte_data = ibm_cffps_read_byte_data,
476		.read_word_data = ibm_cffps_read_word_data,
477	},
478};
479
480static struct pmbus_platform_data ibm_cffps_pdata = {
481	.flags = PMBUS_SKIP_STATUS_CHECK | PMBUS_NO_CAPABILITY,
482};
483
484static int ibm_cffps_probe(struct i2c_client *client)
485{
486	int i, rc;
487	enum versions vs = cffps_unknown;
488	struct dentry *debugfs;
489	struct dentry *ibm_cffps_dir;
490	struct ibm_cffps *psu;
491	const void *md = of_device_get_match_data(&client->dev);
492	const struct i2c_device_id *id;
493
494	if (md) {
495		vs = (enum versions)md;
496	} else {
497		id = i2c_match_id(ibm_cffps_id, client);
498		if (id)
499			vs = (enum versions)id->driver_data;
500	}
501
502	if (vs == cffps_unknown) {
503		u16 ccin_revision = 0;
504		u16 ccin_version = CFFPS_CCIN_VERSION_1;
505		int ccin = i2c_smbus_read_word_swapped(client, CFFPS_CCIN_CMD);
506
507		if (ccin > 0) {
508			ccin_revision = FIELD_GET(CFFPS_CCIN_REVISION, ccin);
509			ccin_version = FIELD_GET(CFFPS_CCIN_VERSION, ccin);
510		}
511
512		switch (ccin_version) {
513		default:
514		case CFFPS_CCIN_VERSION_1:
515			vs = cffps1;
516			break;
517		case CFFPS_CCIN_VERSION_2:
518			vs = cffps2;
519			break;
520		case CFFPS_CCIN_VERSION_3:
521			if (ccin_revision == CFFPS_CCIN_REVISION_LEGACY)
522				vs = cffps1;
523			else
524				vs = cffps2;
525			break;
526		}
527
528		/* Set the client name to include the version number. */
529		snprintf(client->name, I2C_NAME_SIZE, "cffps%d", vs + 1);
530	}
531
532	client->dev.platform_data = &ibm_cffps_pdata;
533	rc = pmbus_do_probe(client, &ibm_cffps_info[vs]);
534	if (rc)
535		return rc;
536
537	/*
538	 * Don't fail the probe if there isn't enough memory for leds and
539	 * debugfs.
540	 */
541	psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
542	if (!psu)
543		return 0;
544
545	psu->version = vs;
546	psu->client = client;
547	mutex_init(&psu->input_history.update_lock);
548	psu->input_history.last_update = jiffies - HZ;
549
550	ibm_cffps_create_led_class(psu);
551
552	/* Don't fail the probe if we can't create debugfs */
553	debugfs = pmbus_get_debugfs_dir(client);
554	if (!debugfs)
555		return 0;
556
557	ibm_cffps_dir = debugfs_create_dir(client->name, debugfs);
558	if (!ibm_cffps_dir)
559		return 0;
560
561	for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
562		psu->debugfs_entries[i] = i;
563
564	debugfs_create_file("input_history", 0444, ibm_cffps_dir,
565			    &psu->debugfs_entries[CFFPS_DEBUGFS_INPUT_HISTORY],
566			    &ibm_cffps_fops);
567	debugfs_create_file("fru", 0444, ibm_cffps_dir,
568			    &psu->debugfs_entries[CFFPS_DEBUGFS_FRU],
569			    &ibm_cffps_fops);
570	debugfs_create_file("part_number", 0444, ibm_cffps_dir,
571			    &psu->debugfs_entries[CFFPS_DEBUGFS_PN],
572			    &ibm_cffps_fops);
573	debugfs_create_file("header", 0444, ibm_cffps_dir,
574			    &psu->debugfs_entries[CFFPS_DEBUGFS_HEADER],
575			    &ibm_cffps_fops);
576	debugfs_create_file("serial_number", 0444, ibm_cffps_dir,
577			    &psu->debugfs_entries[CFFPS_DEBUGFS_SN],
578			    &ibm_cffps_fops);
579	debugfs_create_file("max_power_out", 0444, ibm_cffps_dir,
580			    &psu->debugfs_entries[CFFPS_DEBUGFS_MAX_POWER_OUT],
581			    &ibm_cffps_fops);
582	debugfs_create_file("ccin", 0444, ibm_cffps_dir,
583			    &psu->debugfs_entries[CFFPS_DEBUGFS_CCIN],
584			    &ibm_cffps_fops);
585	debugfs_create_file("fw_version", 0444, ibm_cffps_dir,
586			    &psu->debugfs_entries[CFFPS_DEBUGFS_FW],
587			    &ibm_cffps_fops);
588	debugfs_create_file("on_off_config", 0644, ibm_cffps_dir,
589			    &psu->debugfs_entries[CFFPS_DEBUGFS_ON_OFF_CONFIG],
590			    &ibm_cffps_fops);
591
592	return 0;
593}
594
595static const struct i2c_device_id ibm_cffps_id[] = {
596	{ "ibm_cffps1", cffps1 },
597	{ "ibm_cffps2", cffps2 },
598	{ "ibm_cffps", cffps_unknown },
599	{}
600};
601MODULE_DEVICE_TABLE(i2c, ibm_cffps_id);
602
603static const struct of_device_id ibm_cffps_of_match[] = {
604	{
605		.compatible = "ibm,cffps1",
606		.data = (void *)cffps1
607	},
608	{
609		.compatible = "ibm,cffps2",
610		.data = (void *)cffps2
611	},
612	{
613		.compatible = "ibm,cffps",
614		.data = (void *)cffps_unknown
615	},
616	{}
617};
618MODULE_DEVICE_TABLE(of, ibm_cffps_of_match);
619
620static struct i2c_driver ibm_cffps_driver = {
621	.driver = {
622		.name = "ibm-cffps",
623		.of_match_table = ibm_cffps_of_match,
624	},
625	.probe_new = ibm_cffps_probe,
626	.id_table = ibm_cffps_id,
627};
628
629module_i2c_driver(ibm_cffps_driver);
630
631MODULE_AUTHOR("Eddie James");
632MODULE_DESCRIPTION("PMBus driver for IBM Common Form Factor power supplies");
633MODULE_LICENSE("GPL");
634MODULE_IMPORT_NS(PMBUS);