1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Hardware monitoring driver for Texas Instruments TPS53679
4 *
5 * Copyright (c) 2017 Mellanox Technologies. All rights reserved.
6 * Copyright (c) 2017 Vadim Pasternak <vadimp@mellanox.com>
7 */
8
9#include <linux/bits.h>
10#include <linux/err.h>
11#include <linux/i2c.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include "pmbus.h"
17
18enum chips {
19	tps53647, tps53667, tps53676, tps53679, tps53681, tps53688
20};
21
22#define TPS53647_PAGE_NUM		1
23
24#define TPS53676_USER_DATA_03		0xb3
25#define TPS53676_MAX_PHASES		7
26
27#define TPS53679_PROT_VR12_5MV		0x01 /* VR12.0 mode, 5-mV DAC */
28#define TPS53679_PROT_VR12_5_10MV	0x02 /* VR12.5 mode, 10-mV DAC */
29#define TPS53679_PROT_VR13_10MV		0x04 /* VR13.0 mode, 10-mV DAC */
30#define TPS53679_PROT_IMVP8_5MV		0x05 /* IMVP8 mode, 5-mV DAC */
31#define TPS53679_PROT_VR13_5MV		0x07 /* VR13.0 mode, 5-mV DAC */
32#define TPS53679_PAGE_NUM		2
33
34#define TPS53681_DEVICE_ID		0x81
35
36#define TPS53681_PMBUS_REVISION		0x33
37
38#define TPS53681_MFR_SPECIFIC_20	0xe4	/* Number of phases, per page */
39
40static const struct i2c_device_id tps53679_id[];
41
42static int tps53679_identify_mode(struct i2c_client *client,
43				  struct pmbus_driver_info *info)
44{
45	u8 vout_params;
46	int i, ret;
47
48	for (i = 0; i < info->pages; i++) {
49		/* Read the register with VOUT scaling value.*/
50		ret = pmbus_read_byte_data(client, i, PMBUS_VOUT_MODE);
51		if (ret < 0)
52			return ret;
53
54		vout_params = ret & GENMASK(4, 0);
55
56		switch (vout_params) {
57		case TPS53679_PROT_VR13_10MV:
58		case TPS53679_PROT_VR12_5_10MV:
59			info->vrm_version[i] = vr13;
60			break;
61		case TPS53679_PROT_VR13_5MV:
62		case TPS53679_PROT_VR12_5MV:
63		case TPS53679_PROT_IMVP8_5MV:
64			info->vrm_version[i] = vr12;
65			break;
66		default:
67			return -EINVAL;
68		}
69	}
70
71	return 0;
72}
73
74static int tps53679_identify_phases(struct i2c_client *client,
75				    struct pmbus_driver_info *info)
76{
77	int ret;
78
79	/* On TPS53681, only channel A provides per-phase output current */
80	ret = pmbus_read_byte_data(client, 0, TPS53681_MFR_SPECIFIC_20);
81	if (ret < 0)
82		return ret;
83	info->phases[0] = (ret & 0x07) + 1;
84
85	return 0;
86}
87
88static int tps53679_identify_chip(struct i2c_client *client,
89				  u8 revision, u16 id)
90{
91	u8 buf[I2C_SMBUS_BLOCK_MAX];
92	int ret;
93
94	ret = pmbus_read_byte_data(client, 0, PMBUS_REVISION);
95	if (ret < 0)
96		return ret;
97	if (ret != revision) {
98		dev_err(&client->dev, "Unexpected PMBus revision 0x%x\n", ret);
99		return -ENODEV;
100	}
101
102	ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf);
103	if (ret < 0)
104		return ret;
105	if (ret != 1 || buf[0] != id) {
106		dev_err(&client->dev, "Unexpected device ID 0x%x\n", buf[0]);
107		return -ENODEV;
108	}
109	return 0;
110}
111
112/*
113 * Common identification function for chips with multi-phase support.
114 * Since those chips have special configuration registers, we want to have
115 * some level of reassurance that we are really talking with the chip
116 * being probed. Check PMBus revision and chip ID.
117 */
118static int tps53679_identify_multiphase(struct i2c_client *client,
119					struct pmbus_driver_info *info,
120					int pmbus_rev, int device_id)
121{
122	int ret;
123
124	ret = tps53679_identify_chip(client, pmbus_rev, device_id);
125	if (ret < 0)
126		return ret;
127
128	ret = tps53679_identify_mode(client, info);
129	if (ret < 0)
130		return ret;
131
132	return tps53679_identify_phases(client, info);
133}
134
135static int tps53679_identify(struct i2c_client *client,
136			     struct pmbus_driver_info *info)
137{
138	return tps53679_identify_mode(client, info);
139}
140
141static int tps53681_identify(struct i2c_client *client,
142			     struct pmbus_driver_info *info)
143{
144	return tps53679_identify_multiphase(client, info,
145					    TPS53681_PMBUS_REVISION,
146					    TPS53681_DEVICE_ID);
147}
148
149static int tps53676_identify(struct i2c_client *client,
150			     struct pmbus_driver_info *info)
151{
152	u8 buf[I2C_SMBUS_BLOCK_MAX];
153	int phases_a = 0, phases_b = 0;
154	int i, ret;
155
156	ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf);
157	if (ret < 0)
158		return ret;
159	if (strncmp("TI\x53\x67\x60", buf, 5)) {
160		dev_err(&client->dev, "Unexpected device ID: %s\n", buf);
161		return -ENODEV;
162	}
163
164	ret = i2c_smbus_read_block_data(client, TPS53676_USER_DATA_03, buf);
165	if (ret < 0)
166		return ret;
167	if (ret != 24)
168		return -EIO;
169	for (i = 0; i < 2 * TPS53676_MAX_PHASES; i += 2) {
170		if (buf[i + 1] & 0x80) {
171			if (buf[i] & 0x08)
172				phases_b++;
173			else
174				phases_a++;
175		}
176	}
177
178	info->format[PSC_VOLTAGE_OUT] = linear;
179	info->pages = 1;
180	info->phases[0] = phases_a;
181	if (phases_b > 0) {
182		info->pages = 2;
183		info->phases[1] = phases_b;
184	}
185	return 0;
186}
187
188static int tps53681_read_word_data(struct i2c_client *client, int page,
189				   int phase, int reg)
190{
191	/*
192	 * For reading the total output current (READ_IOUT) for all phases,
193	 * the chip datasheet is a bit vague. It says "PHASE must be set to
194	 * FFh to access all phases simultaneously. PHASE may also be set to
195	 * 80h readack (!) the total phase current".
196	 * Experiments show that the command does _not_ report the total
197	 * current for all phases if the phase is set to 0xff. Instead, it
198	 * appears to report the current of one of the phases. Override phase
199	 * parameter with 0x80 when reading the total output current on page 0.
200	 */
201	if (reg == PMBUS_READ_IOUT && page == 0 && phase == 0xff)
202		return pmbus_read_word_data(client, page, 0x80, reg);
203	return -ENODATA;
204}
205
206static struct pmbus_driver_info tps53679_info = {
207	.format[PSC_VOLTAGE_IN] = linear,
208	.format[PSC_VOLTAGE_OUT] = vid,
209	.format[PSC_TEMPERATURE] = linear,
210	.format[PSC_CURRENT_OUT] = linear,
211	.format[PSC_POWER] = linear,
212	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
213		PMBUS_HAVE_STATUS_INPUT |
214		PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
215		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
216		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
217		PMBUS_HAVE_POUT,
218	.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
219		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
220		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
221		PMBUS_HAVE_POUT,
222	.pfunc[0] = PMBUS_HAVE_IOUT,
223	.pfunc[1] = PMBUS_HAVE_IOUT,
224	.pfunc[2] = PMBUS_HAVE_IOUT,
225	.pfunc[3] = PMBUS_HAVE_IOUT,
226	.pfunc[4] = PMBUS_HAVE_IOUT,
227	.pfunc[5] = PMBUS_HAVE_IOUT,
228	.pfunc[6] = PMBUS_HAVE_IOUT,
229};
230
231static int tps53679_probe(struct i2c_client *client)
232{
233	struct device *dev = &client->dev;
234	struct pmbus_driver_info *info;
235	enum chips chip_id;
236
237	if (dev->of_node)
238		chip_id = (uintptr_t)of_device_get_match_data(dev);
239	else
240		chip_id = i2c_match_id(tps53679_id, client)->driver_data;
241
242	info = devm_kmemdup(dev, &tps53679_info, sizeof(*info), GFP_KERNEL);
243	if (!info)
244		return -ENOMEM;
245
246	switch (chip_id) {
247	case tps53647:
248	case tps53667:
249		info->pages = TPS53647_PAGE_NUM;
250		info->identify = tps53679_identify;
251		break;
252	case tps53676:
253		info->identify = tps53676_identify;
254		break;
255	case tps53679:
256	case tps53688:
257		info->pages = TPS53679_PAGE_NUM;
258		info->identify = tps53679_identify;
259		break;
260	case tps53681:
261		info->pages = TPS53679_PAGE_NUM;
262		info->phases[0] = 6;
263		info->identify = tps53681_identify;
264		info->read_word_data = tps53681_read_word_data;
265		break;
266	default:
267		return -ENODEV;
268	}
269
270	return pmbus_do_probe(client, info);
271}
272
273static const struct i2c_device_id tps53679_id[] = {
274	{"bmr474", tps53676},
275	{"tps53647", tps53647},
276	{"tps53667", tps53667},
277	{"tps53676", tps53676},
278	{"tps53679", tps53679},
279	{"tps53681", tps53681},
280	{"tps53688", tps53688},
281	{}
282};
283
284MODULE_DEVICE_TABLE(i2c, tps53679_id);
285
286static const struct of_device_id __maybe_unused tps53679_of_match[] = {
287	{.compatible = "ti,tps53647", .data = (void *)tps53647},
288	{.compatible = "ti,tps53667", .data = (void *)tps53667},
289	{.compatible = "ti,tps53676", .data = (void *)tps53676},
290	{.compatible = "ti,tps53679", .data = (void *)tps53679},
291	{.compatible = "ti,tps53681", .data = (void *)tps53681},
292	{.compatible = "ti,tps53688", .data = (void *)tps53688},
293	{}
294};
295MODULE_DEVICE_TABLE(of, tps53679_of_match);
296
297static struct i2c_driver tps53679_driver = {
298	.driver = {
299		.name = "tps53679",
300		.of_match_table = of_match_ptr(tps53679_of_match),
301	},
302	.probe = tps53679_probe,
303	.id_table = tps53679_id,
304};
305
306module_i2c_driver(tps53679_driver);
307
308MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
309MODULE_DESCRIPTION("PMBus driver for Texas Instruments TPS53679");
310MODULE_LICENSE("GPL");
311MODULE_IMPORT_NS(PMBUS);
312