xref: /linux/drivers/hwmon/pmbus/adm1266.c (revision 2be86a8c57773bce1b5c845c49e0bfa3caac838c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ADM1266 - Cascadable Super Sequencer with Margin
4  * Control and Fault Recording
5  *
6  * Copyright 2020 Analog Devices Inc.
7  */
8 
9 #include <linux/bitfield.h>
10 #include <linux/crc8.h>
11 #include <linux/debugfs.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/i2c.h>
14 #include <linux/i2c-smbus.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/nvmem-consumer.h>
19 #include <linux/nvmem-provider.h>
20 #include "pmbus.h"
21 #include <linux/slab.h>
22 #include <linux/timekeeping.h>
23 
24 #define ADM1266_BLACKBOX_CONFIG	0xD3
25 #define ADM1266_PDIO_CONFIG	0xD4
26 #define ADM1266_READ_STATE	0xD9
27 #define ADM1266_READ_BLACKBOX	0xDE
28 #define ADM1266_SET_RTC		0xDF
29 #define ADM1266_GPIO_CONFIG	0xE1
30 #define ADM1266_BLACKBOX_INFO	0xE6
31 #define ADM1266_PDIO_STATUS	0xE9
32 #define ADM1266_GPIO_STATUS	0xEA
33 
34 /* ADM1266 GPIO defines */
35 #define ADM1266_GPIO_NR			9
36 #define ADM1266_GPIO_FUNCTIONS(x)	FIELD_GET(BIT(0), x)
37 #define ADM1266_GPIO_INPUT_EN(x)	FIELD_GET(BIT(2), x)
38 #define ADM1266_GPIO_OUTPUT_EN(x)	FIELD_GET(BIT(3), x)
39 #define ADM1266_GPIO_OPEN_DRAIN(x)	FIELD_GET(BIT(4), x)
40 
41 /* ADM1266 PDIO defines */
42 #define ADM1266_PDIO_NR			16
43 #define ADM1266_PDIO_PIN_CFG(x)		FIELD_GET(GENMASK(15, 13), x)
44 #define ADM1266_PDIO_GLITCH_FILT(x)	FIELD_GET(GENMASK(12, 9), x)
45 #define ADM1266_PDIO_OUT_CFG(x)		FIELD_GET(GENMASK(2, 0), x)
46 
47 #define ADM1266_BLACKBOX_OFFSET		0
48 #define ADM1266_BLACKBOX_SIZE		64
49 #define ADM1266_BLACKBOX_MAX_RECORDS	32
50 
51 #define ADM1266_PMBUS_BLOCK_MAX		255
52 
53 struct adm1266_data {
54 	struct pmbus_driver_info info;
55 	struct gpio_chip gc;
56 	const char *gpio_names[ADM1266_GPIO_NR + ADM1266_PDIO_NR];
57 	struct i2c_client *client;
58 	struct dentry *debugfs_dir;
59 	struct nvmem_config nvmem_config;
60 	struct nvmem_device *nvmem;
61 	u8 *dev_mem;
62 	struct mutex buf_mutex;
63 	u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 1] ____cacheline_aligned;
64 	u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 2] ____cacheline_aligned;
65 };
66 
67 static const struct nvmem_cell_info adm1266_nvmem_cells[] = {
68 	{
69 		.name           = "blackbox",
70 		.offset         = ADM1266_BLACKBOX_OFFSET,
71 		.bytes          = 2048,
72 	},
73 };
74 
75 DECLARE_CRC8_TABLE(pmbus_crc_table);
76 
77 /*
78  * Different from Block Read as it sends data and waits for the slave to
79  * return a value dependent on that data. The protocol is simply a Write Block
80  * followed by a Read Block without the Read-Block command field and the
81  * Write-Block STOP bit.
82  */
adm1266_pmbus_block_xfer(struct adm1266_data * data,u8 cmd,u8 w_len,u8 * data_w,u8 * data_r)83 static int adm1266_pmbus_block_xfer(struct adm1266_data *data, u8 cmd, u8 w_len, u8 *data_w,
84 				    u8 *data_r)
85 {
86 	struct i2c_client *client = data->client;
87 	struct i2c_msg msgs[2] = {
88 		{
89 			.addr = client->addr,
90 			.flags = I2C_M_DMA_SAFE,
91 			.buf = data->write_buf,
92 			.len = w_len + 2,
93 		},
94 		{
95 			.addr = client->addr,
96 			.flags = I2C_M_RD | I2C_M_DMA_SAFE,
97 			.buf = data->read_buf,
98 			.len = ADM1266_PMBUS_BLOCK_MAX + 2,
99 		}
100 	};
101 	u8 addr;
102 	u8 crc;
103 	int ret;
104 
105 	mutex_lock(&data->buf_mutex);
106 
107 	msgs[0].buf[0] = cmd;
108 	msgs[0].buf[1] = w_len;
109 	memcpy(&msgs[0].buf[2], data_w, w_len);
110 
111 	ret = i2c_transfer(client->adapter, msgs, 2);
112 	if (ret != 2) {
113 		if (ret >= 0)
114 			ret = -EPROTO;
115 
116 		mutex_unlock(&data->buf_mutex);
117 
118 		return ret;
119 	}
120 
121 	if (client->flags & I2C_CLIENT_PEC) {
122 		addr = i2c_8bit_addr_from_msg(&msgs[0]);
123 		crc = crc8(pmbus_crc_table, &addr, 1, 0);
124 		crc = crc8(pmbus_crc_table, msgs[0].buf,  msgs[0].len, crc);
125 
126 		addr = i2c_8bit_addr_from_msg(&msgs[1]);
127 		crc = crc8(pmbus_crc_table, &addr, 1, crc);
128 		crc = crc8(pmbus_crc_table, msgs[1].buf,  msgs[1].buf[0] + 1, crc);
129 
130 		if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) {
131 			mutex_unlock(&data->buf_mutex);
132 			return -EBADMSG;
133 		}
134 	}
135 
136 	memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
137 
138 	ret = msgs[1].buf[0];
139 	mutex_unlock(&data->buf_mutex);
140 
141 	return ret;
142 }
143 
144 static const unsigned int adm1266_gpio_mapping[ADM1266_GPIO_NR][2] = {
145 	{1, 0},
146 	{2, 1},
147 	{3, 2},
148 	{4, 8},
149 	{5, 9},
150 	{6, 10},
151 	{7, 11},
152 	{8, 6},
153 	{9, 7},
154 };
155 
156 static const char *adm1266_names[ADM1266_GPIO_NR + ADM1266_PDIO_NR] = {
157 	"GPIO1", "GPIO2", "GPIO3", "GPIO4", "GPIO5", "GPIO6", "GPIO7", "GPIO8",
158 	"GPIO9", "PDIO1", "PDIO2", "PDIO3", "PDIO4", "PDIO5", "PDIO6",
159 	"PDIO7", "PDIO8", "PDIO9", "PDIO10", "PDIO11", "PDIO12", "PDIO13",
160 	"PDIO14", "PDIO15", "PDIO16",
161 };
162 
adm1266_gpio_get(struct gpio_chip * chip,unsigned int offset)163 static int adm1266_gpio_get(struct gpio_chip *chip, unsigned int offset)
164 {
165 	struct adm1266_data *data = gpiochip_get_data(chip);
166 	u8 read_buf[I2C_SMBUS_BLOCK_MAX + 1];
167 	unsigned long pins_status;
168 	unsigned int pmbus_cmd;
169 	int ret;
170 
171 	if (offset < ADM1266_GPIO_NR)
172 		pmbus_cmd = ADM1266_GPIO_STATUS;
173 	else
174 		pmbus_cmd = ADM1266_PDIO_STATUS;
175 
176 	guard(pmbus_lock)(data->client);
177 
178 	ret = i2c_smbus_read_block_data(data->client, pmbus_cmd, read_buf);
179 	if (ret < 0)
180 		return ret;
181 	if (ret < 2)
182 		return -EIO;
183 
184 	pins_status = read_buf[0] + (read_buf[1] << 8);
185 	if (offset < ADM1266_GPIO_NR)
186 		return test_bit(adm1266_gpio_mapping[offset][1], &pins_status);
187 
188 	return test_bit(offset - ADM1266_GPIO_NR, &pins_status);
189 }
190 
adm1266_gpio_get_multiple(struct gpio_chip * chip,unsigned long * mask,unsigned long * bits)191 static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
192 				     unsigned long *bits)
193 {
194 	struct adm1266_data *data = gpiochip_get_data(chip);
195 	u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1];
196 	unsigned long status;
197 	unsigned int gpio_nr;
198 	int ret;
199 
200 	guard(pmbus_lock)(data->client);
201 
202 	ret = i2c_smbus_read_block_data(data->client, ADM1266_GPIO_STATUS, read_buf);
203 	if (ret < 0)
204 		return ret;
205 	if (ret < 2)
206 		return -EIO;
207 
208 	status = read_buf[0] + (read_buf[1] << 8);
209 
210 	*bits = 0;
211 	for_each_set_bit(gpio_nr, mask, ADM1266_GPIO_NR) {
212 		if (test_bit(adm1266_gpio_mapping[gpio_nr][1], &status))
213 			set_bit(gpio_nr, bits);
214 	}
215 
216 	ret = i2c_smbus_read_block_data(data->client, ADM1266_PDIO_STATUS, read_buf);
217 	if (ret < 0)
218 		return ret;
219 	if (ret < 2)
220 		return -EIO;
221 
222 	status = read_buf[0] + (read_buf[1] << 8);
223 
224 	for_each_set_bit_from(gpio_nr, mask, ADM1266_GPIO_NR + ADM1266_PDIO_NR) {
225 		if (test_bit(gpio_nr - ADM1266_GPIO_NR, &status))
226 			set_bit(gpio_nr, bits);
227 	}
228 
229 	return 0;
230 }
231 
adm1266_gpio_dbg_show(struct seq_file * s,struct gpio_chip * chip)232 static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
233 {
234 	struct adm1266_data *data = gpiochip_get_data(chip);
235 	u8 read_buf[ADM1266_PMBUS_BLOCK_MAX + 1];
236 	unsigned long gpio_config;
237 	unsigned long pdio_config;
238 	unsigned long pin_cfg;
239 	u8 write_cmd;
240 	int ret;
241 	int i;
242 
243 	guard(pmbus_lock)(data->client);
244 
245 	for (i = 0; i < ADM1266_GPIO_NR; i++) {
246 		write_cmd = adm1266_gpio_mapping[i][1];
247 		ret = adm1266_pmbus_block_xfer(data, ADM1266_GPIO_CONFIG, 1, &write_cmd, read_buf);
248 		if (ret != 2)
249 			return;
250 
251 		gpio_config = read_buf[0];
252 		seq_puts(s, adm1266_names[i]);
253 
254 		seq_puts(s, " ( ");
255 		if (!ADM1266_GPIO_FUNCTIONS(gpio_config)) {
256 			seq_puts(s, "high-Z )\n");
257 			continue;
258 		}
259 		if (ADM1266_GPIO_INPUT_EN(gpio_config))
260 			seq_puts(s, "input ");
261 		if (ADM1266_GPIO_OUTPUT_EN(gpio_config))
262 			seq_puts(s, "output ");
263 		if (ADM1266_GPIO_OPEN_DRAIN(gpio_config))
264 			seq_puts(s, "open-drain )\n");
265 		else
266 			seq_puts(s, "push-pull )\n");
267 	}
268 
269 	write_cmd = 0xFF;
270 	ret = adm1266_pmbus_block_xfer(data, ADM1266_PDIO_CONFIG, 1, &write_cmd, read_buf);
271 	if (ret != 32)
272 		return;
273 
274 	for (i = 0; i < ADM1266_PDIO_NR; i++) {
275 		seq_puts(s, adm1266_names[ADM1266_GPIO_NR + i]);
276 
277 		pdio_config = read_buf[2 * i];
278 		pdio_config += (read_buf[2 * i + 1] << 8);
279 		pin_cfg = ADM1266_PDIO_PIN_CFG(pdio_config);
280 
281 		seq_puts(s, " ( ");
282 		if (!pin_cfg || pin_cfg > 5) {
283 			seq_puts(s, "high-Z )\n");
284 			continue;
285 		}
286 
287 		if (pin_cfg & BIT(0))
288 			seq_puts(s, "output ");
289 
290 		if (pin_cfg & BIT(1))
291 			seq_puts(s, "input ");
292 
293 		seq_puts(s, ")\n");
294 	}
295 }
296 
adm1266_config_gpio(struct adm1266_data * data)297 static int adm1266_config_gpio(struct adm1266_data *data)
298 {
299 	const char *name = dev_name(&data->client->dev);
300 	char *gpio_name;
301 	int ret;
302 	int i;
303 
304 	for (i = 0; i < ARRAY_SIZE(data->gpio_names); i++) {
305 		gpio_name = devm_kasprintf(&data->client->dev, GFP_KERNEL, "adm1266-%d-%x-%s",
306 					   data->client->adapter->nr, data->client->addr,
307 					   adm1266_names[i]);
308 		if (!gpio_name)
309 			return -ENOMEM;
310 
311 		data->gpio_names[i] = gpio_name;
312 	}
313 
314 	data->gc.label = name;
315 	data->gc.parent = &data->client->dev;
316 	data->gc.owner = THIS_MODULE;
317 	data->gc.can_sleep = true;
318 	data->gc.base = -1;
319 	data->gc.names = data->gpio_names;
320 	data->gc.ngpio = ARRAY_SIZE(data->gpio_names);
321 	data->gc.get = adm1266_gpio_get;
322 	data->gc.get_multiple = adm1266_gpio_get_multiple;
323 	data->gc.dbg_show = adm1266_gpio_dbg_show;
324 
325 	ret = devm_gpiochip_add_data(&data->client->dev, &data->gc, data);
326 	if (ret)
327 		dev_err(&data->client->dev, "GPIO registering failed (%d)\n", ret);
328 
329 	return ret;
330 }
331 
adm1266_state_read(struct seq_file * s,void * pdata)332 static int adm1266_state_read(struct seq_file *s, void *pdata)
333 {
334 	struct device *dev = s->private;
335 	struct i2c_client *client = to_i2c_client(dev);
336 	int ret;
337 
338 	guard(pmbus_lock)(client);
339 	ret = i2c_smbus_read_word_data(client, ADM1266_READ_STATE);
340 	if (ret < 0)
341 		return ret;
342 
343 	seq_printf(s, "%d\n", ret);
344 
345 	return 0;
346 }
347 
adm1266_init_debugfs(struct adm1266_data * data)348 static void adm1266_init_debugfs(struct adm1266_data *data)
349 {
350 	struct dentry *root;
351 
352 	root = pmbus_get_debugfs_dir(data->client);
353 	if (!root)
354 		return;
355 
356 	data->debugfs_dir = debugfs_create_dir(data->client->name, root);
357 
358 	debugfs_create_devm_seqfile(&data->client->dev, "sequencer_state", data->debugfs_dir,
359 				    adm1266_state_read);
360 }
361 
adm1266_nvmem_read_blackbox(struct adm1266_data * data,u8 * read_buff)362 static int adm1266_nvmem_read_blackbox(struct adm1266_data *data, u8 *read_buff)
363 {
364 	u8 record[ADM1266_PMBUS_BLOCK_MAX];
365 	int record_count;
366 	char index;
367 	u8 buf[I2C_SMBUS_BLOCK_MAX];
368 	int ret;
369 
370 	ret = i2c_smbus_read_block_data(data->client, ADM1266_BLACKBOX_INFO, buf);
371 	if (ret < 0)
372 		return ret;
373 
374 	if (ret != 4)
375 		return -EIO;
376 
377 	record_count = buf[3];
378 	if (record_count > ADM1266_BLACKBOX_MAX_RECORDS)
379 		return -EIO;
380 
381 	for (index = 0; index < record_count; index++) {
382 		ret = adm1266_pmbus_block_xfer(data, ADM1266_READ_BLACKBOX, 1, &index, record);
383 		if (ret < 0)
384 			return ret;
385 
386 		if (ret != ADM1266_BLACKBOX_SIZE)
387 			return -EIO;
388 
389 		memcpy(read_buff, record, ADM1266_BLACKBOX_SIZE);
390 		read_buff += ADM1266_BLACKBOX_SIZE;
391 	}
392 
393 	return 0;
394 }
395 
adm1266_nvmem_read(void * priv,unsigned int offset,void * val,size_t bytes)396 static int adm1266_nvmem_read(void *priv, unsigned int offset, void *val, size_t bytes)
397 {
398 	struct adm1266_data *data = priv;
399 	int ret;
400 
401 	if (offset + bytes > data->nvmem_config.size)
402 		return -EINVAL;
403 
404 	guard(pmbus_lock)(data->client);
405 
406 	if (offset == 0) {
407 		memset(data->dev_mem, 0, data->nvmem_config.size);
408 
409 		ret = adm1266_nvmem_read_blackbox(data, data->dev_mem);
410 		if (ret) {
411 			dev_err(&data->client->dev, "Could not read blackbox!");
412 			return ret;
413 		}
414 	}
415 
416 	memcpy(val, data->dev_mem + offset, bytes);
417 
418 	return 0;
419 }
420 
adm1266_config_nvmem(struct adm1266_data * data)421 static int adm1266_config_nvmem(struct adm1266_data *data)
422 {
423 	data->nvmem_config.name = dev_name(&data->client->dev);
424 	data->nvmem_config.dev = &data->client->dev;
425 	data->nvmem_config.root_only = true;
426 	data->nvmem_config.read_only = true;
427 	data->nvmem_config.owner = THIS_MODULE;
428 	data->nvmem_config.reg_read = adm1266_nvmem_read;
429 	data->nvmem_config.cells = adm1266_nvmem_cells;
430 	data->nvmem_config.ncells = ARRAY_SIZE(adm1266_nvmem_cells);
431 	data->nvmem_config.priv = data;
432 	data->nvmem_config.stride = 1;
433 	data->nvmem_config.word_size = 1;
434 	data->nvmem_config.size = adm1266_nvmem_cells[0].bytes;
435 
436 	data->dev_mem = devm_kzalloc(&data->client->dev, data->nvmem_config.size, GFP_KERNEL);
437 	if (!data->dev_mem)
438 		return -ENOMEM;
439 
440 	data->nvmem = devm_nvmem_register(&data->client->dev, &data->nvmem_config);
441 	if (IS_ERR(data->nvmem)) {
442 		dev_err(&data->client->dev, "Could not register nvmem!");
443 		return PTR_ERR(data->nvmem);
444 	}
445 
446 	return 0;
447 }
448 
adm1266_set_rtc(struct adm1266_data * data)449 static int adm1266_set_rtc(struct adm1266_data *data)
450 {
451 	time64_t kt;
452 	char write_buf[6];
453 	int i;
454 
455 	kt = ktime_get_real_seconds();
456 
457 	memset(write_buf, 0, sizeof(write_buf));
458 
459 	for (i = 0; i < 4; i++)
460 		write_buf[2 + i] = (kt >> (i * 8)) & 0xFF;
461 
462 	return i2c_smbus_write_block_data(data->client, ADM1266_SET_RTC, sizeof(write_buf),
463 					  write_buf);
464 }
465 
adm1266_probe(struct i2c_client * client)466 static int adm1266_probe(struct i2c_client *client)
467 {
468 	struct adm1266_data *data;
469 	int ret;
470 	int i;
471 
472 	data = devm_kzalloc(&client->dev, sizeof(struct adm1266_data), GFP_KERNEL);
473 	if (!data)
474 		return -ENOMEM;
475 
476 	data->client = client;
477 	data->info.pages = 17;
478 	data->info.format[PSC_VOLTAGE_OUT] = linear;
479 	for (i = 0; i < data->info.pages; i++)
480 		data->info.func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT;
481 
482 	crc8_populate_msb(pmbus_crc_table, 0x7);
483 	mutex_init(&data->buf_mutex);
484 
485 	ret = adm1266_set_rtc(data);
486 	if (ret < 0)
487 		return ret;
488 
489 	ret = pmbus_do_probe(client, &data->info);
490 	if (ret)
491 		return ret;
492 
493 	ret = adm1266_config_nvmem(data);
494 	if (ret < 0)
495 		return ret;
496 
497 	ret = adm1266_config_gpio(data);
498 	if (ret < 0)
499 		return ret;
500 
501 	adm1266_init_debugfs(data);
502 
503 	return 0;
504 }
505 
506 static const struct of_device_id adm1266_of_match[] = {
507 	{ .compatible = "adi,adm1266" },
508 	{ }
509 };
510 MODULE_DEVICE_TABLE(of, adm1266_of_match);
511 
512 static const struct i2c_device_id adm1266_id[] = {
513 	{ "adm1266" },
514 	{ }
515 };
516 MODULE_DEVICE_TABLE(i2c, adm1266_id);
517 
518 static struct i2c_driver adm1266_driver = {
519 	.driver = {
520 		   .name = "adm1266",
521 		   .of_match_table = adm1266_of_match,
522 		  },
523 	.probe = adm1266_probe,
524 	.id_table = adm1266_id,
525 };
526 
527 module_i2c_driver(adm1266_driver);
528 
529 MODULE_AUTHOR("Alexandru Tachici <alexandru.tachici@analog.com>");
530 MODULE_DESCRIPTION("PMBus driver for Analog Devices ADM1266");
531 MODULE_LICENSE("GPL v2");
532 MODULE_IMPORT_NS("PMBUS");
533