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_device.h>
16 #include "pmbus.h"
17 
18 enum 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 
40 static const struct i2c_device_id tps53679_id[];
41 
tps53679_identify_mode(struct i2c_client * client,struct pmbus_driver_info * info)42 static 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 
tps53679_identify_phases(struct i2c_client * client,struct pmbus_driver_info * info)74 static 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 
tps53679_identify_chip(struct i2c_client * client,u8 revision,u16 id)88 static 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  */
tps53679_identify_multiphase(struct i2c_client * client,struct pmbus_driver_info * info,int pmbus_rev,int device_id)118 static 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 
tps53679_identify(struct i2c_client * client,struct pmbus_driver_info * info)135 static int tps53679_identify(struct i2c_client *client,
136 			     struct pmbus_driver_info *info)
137 {
138 	return tps53679_identify_mode(client, info);
139 }
140 
tps53681_identify(struct i2c_client * client,struct pmbus_driver_info * info)141 static 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 
tps53676_identify(struct i2c_client * client,struct pmbus_driver_info * info)149 static 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 
tps53681_read_word_data(struct i2c_client * client,int page,int phase,int reg)188 static 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 
206 static 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 
tps53679_probe(struct i2c_client * client)231 static 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 = (enum chips)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 
273 static 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 
284 MODULE_DEVICE_TABLE(i2c, tps53679_id);
285 
286 static 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 };
295 MODULE_DEVICE_TABLE(of, tps53679_of_match);
296 
297 static struct i2c_driver tps53679_driver = {
298 	.driver = {
299 		.name = "tps53679",
300 		.of_match_table = of_match_ptr(tps53679_of_match),
301 	},
302 	.probe_new = tps53679_probe,
303 	.id_table = tps53679_id,
304 };
305 
306 module_i2c_driver(tps53679_driver);
307 
308 MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
309 MODULE_DESCRIPTION("PMBus driver for Texas Instruments TPS53679");
310 MODULE_LICENSE("GPL");
311 MODULE_IMPORT_NS(PMBUS);
312