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