xref: /openbmc/linux/drivers/hwmon/pmbus/tps53679.c (revision 0bf49ffb)
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, tps53679, tps53681, tps53688
20 };
21 
22 #define TPS53647_PAGE_NUM		1
23 
24 #define TPS53679_PROT_VR12_5MV		0x01 /* VR12.0 mode, 5-mV DAC */
25 #define TPS53679_PROT_VR12_5_10MV	0x02 /* VR12.5 mode, 10-mV DAC */
26 #define TPS53679_PROT_VR13_10MV		0x04 /* VR13.0 mode, 10-mV DAC */
27 #define TPS53679_PROT_IMVP8_5MV		0x05 /* IMVP8 mode, 5-mV DAC */
28 #define TPS53679_PROT_VR13_5MV		0x07 /* VR13.0 mode, 5-mV DAC */
29 #define TPS53679_PAGE_NUM		2
30 
31 #define TPS53681_DEVICE_ID		0x81
32 
33 #define TPS53681_PMBUS_REVISION		0x33
34 
35 #define TPS53681_MFR_SPECIFIC_20	0xe4	/* Number of phases, per page */
36 
37 static const struct i2c_device_id tps53679_id[];
38 
39 static int tps53679_identify_mode(struct i2c_client *client,
40 				  struct pmbus_driver_info *info)
41 {
42 	u8 vout_params;
43 	int i, ret;
44 
45 	for (i = 0; i < info->pages; i++) {
46 		/* Read the register with VOUT scaling value.*/
47 		ret = pmbus_read_byte_data(client, i, PMBUS_VOUT_MODE);
48 		if (ret < 0)
49 			return ret;
50 
51 		vout_params = ret & GENMASK(4, 0);
52 
53 		switch (vout_params) {
54 		case TPS53679_PROT_VR13_10MV:
55 		case TPS53679_PROT_VR12_5_10MV:
56 			info->vrm_version[i] = vr13;
57 			break;
58 		case TPS53679_PROT_VR13_5MV:
59 		case TPS53679_PROT_VR12_5MV:
60 		case TPS53679_PROT_IMVP8_5MV:
61 			info->vrm_version[i] = vr12;
62 			break;
63 		default:
64 			return -EINVAL;
65 		}
66 	}
67 
68 	return 0;
69 }
70 
71 static int tps53679_identify_phases(struct i2c_client *client,
72 				    struct pmbus_driver_info *info)
73 {
74 	int ret;
75 
76 	/* On TPS53681, only channel A provides per-phase output current */
77 	ret = pmbus_read_byte_data(client, 0, TPS53681_MFR_SPECIFIC_20);
78 	if (ret < 0)
79 		return ret;
80 	info->phases[0] = (ret & 0x07) + 1;
81 
82 	return 0;
83 }
84 
85 static int tps53679_identify_chip(struct i2c_client *client,
86 				  u8 revision, u16 id)
87 {
88 	u8 buf[I2C_SMBUS_BLOCK_MAX];
89 	int ret;
90 
91 	ret = pmbus_read_byte_data(client, 0, PMBUS_REVISION);
92 	if (ret < 0)
93 		return ret;
94 	if (ret != revision) {
95 		dev_err(&client->dev, "Unexpected PMBus revision 0x%x\n", ret);
96 		return -ENODEV;
97 	}
98 
99 	ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf);
100 	if (ret < 0)
101 		return ret;
102 	if (ret != 1 || buf[0] != id) {
103 		dev_err(&client->dev, "Unexpected device ID 0x%x\n", buf[0]);
104 		return -ENODEV;
105 	}
106 	return 0;
107 }
108 
109 /*
110  * Common identification function for chips with multi-phase support.
111  * Since those chips have special configuration registers, we want to have
112  * some level of reassurance that we are really talking with the chip
113  * being probed. Check PMBus revision and chip ID.
114  */
115 static int tps53679_identify_multiphase(struct i2c_client *client,
116 					struct pmbus_driver_info *info,
117 					int pmbus_rev, int device_id)
118 {
119 	int ret;
120 
121 	ret = tps53679_identify_chip(client, pmbus_rev, device_id);
122 	if (ret < 0)
123 		return ret;
124 
125 	ret = tps53679_identify_mode(client, info);
126 	if (ret < 0)
127 		return ret;
128 
129 	return tps53679_identify_phases(client, info);
130 }
131 
132 static int tps53679_identify(struct i2c_client *client,
133 			     struct pmbus_driver_info *info)
134 {
135 	return tps53679_identify_mode(client, info);
136 }
137 
138 static int tps53681_identify(struct i2c_client *client,
139 			     struct pmbus_driver_info *info)
140 {
141 	return tps53679_identify_multiphase(client, info,
142 					    TPS53681_PMBUS_REVISION,
143 					    TPS53681_DEVICE_ID);
144 }
145 
146 static int tps53681_read_word_data(struct i2c_client *client, int page,
147 				   int phase, int reg)
148 {
149 	/*
150 	 * For reading the total output current (READ_IOUT) for all phases,
151 	 * the chip datasheet is a bit vague. It says "PHASE must be set to
152 	 * FFh to access all phases simultaneously. PHASE may also be set to
153 	 * 80h readack (!) the total phase current".
154 	 * Experiments show that the command does _not_ report the total
155 	 * current for all phases if the phase is set to 0xff. Instead, it
156 	 * appears to report the current of one of the phases. Override phase
157 	 * parameter with 0x80 when reading the total output current on page 0.
158 	 */
159 	if (reg == PMBUS_READ_IOUT && page == 0 && phase == 0xff)
160 		return pmbus_read_word_data(client, page, 0x80, reg);
161 	return -ENODATA;
162 }
163 
164 static struct pmbus_driver_info tps53679_info = {
165 	.format[PSC_VOLTAGE_IN] = linear,
166 	.format[PSC_VOLTAGE_OUT] = vid,
167 	.format[PSC_TEMPERATURE] = linear,
168 	.format[PSC_CURRENT_OUT] = linear,
169 	.format[PSC_POWER] = linear,
170 	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
171 		PMBUS_HAVE_STATUS_INPUT |
172 		PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
173 		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
174 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
175 		PMBUS_HAVE_POUT,
176 	.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
177 		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
178 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
179 		PMBUS_HAVE_POUT,
180 	.pfunc[0] = PMBUS_HAVE_IOUT,
181 	.pfunc[1] = PMBUS_HAVE_IOUT,
182 	.pfunc[2] = PMBUS_HAVE_IOUT,
183 	.pfunc[3] = PMBUS_HAVE_IOUT,
184 	.pfunc[4] = PMBUS_HAVE_IOUT,
185 	.pfunc[5] = PMBUS_HAVE_IOUT,
186 };
187 
188 static int tps53679_probe(struct i2c_client *client)
189 {
190 	struct device *dev = &client->dev;
191 	struct pmbus_driver_info *info;
192 	enum chips chip_id;
193 
194 	if (dev->of_node)
195 		chip_id = (enum chips)of_device_get_match_data(dev);
196 	else
197 		chip_id = i2c_match_id(tps53679_id, client)->driver_data;
198 
199 	info = devm_kmemdup(dev, &tps53679_info, sizeof(*info), GFP_KERNEL);
200 	if (!info)
201 		return -ENOMEM;
202 
203 	switch (chip_id) {
204 	case tps53647:
205 	case tps53667:
206 		info->pages = TPS53647_PAGE_NUM;
207 		info->identify = tps53679_identify;
208 		break;
209 	case tps53679:
210 	case tps53688:
211 		info->pages = TPS53679_PAGE_NUM;
212 		info->identify = tps53679_identify;
213 		break;
214 	case tps53681:
215 		info->pages = TPS53679_PAGE_NUM;
216 		info->phases[0] = 6;
217 		info->identify = tps53681_identify;
218 		info->read_word_data = tps53681_read_word_data;
219 		break;
220 	default:
221 		return -ENODEV;
222 	}
223 
224 	return pmbus_do_probe(client, info);
225 }
226 
227 static const struct i2c_device_id tps53679_id[] = {
228 	{"tps53647", tps53647},
229 	{"tps53667", tps53667},
230 	{"tps53679", tps53679},
231 	{"tps53681", tps53681},
232 	{"tps53688", tps53688},
233 	{}
234 };
235 
236 MODULE_DEVICE_TABLE(i2c, tps53679_id);
237 
238 static const struct of_device_id __maybe_unused tps53679_of_match[] = {
239 	{.compatible = "ti,tps53647", .data = (void *)tps53647},
240 	{.compatible = "ti,tps53667", .data = (void *)tps53667},
241 	{.compatible = "ti,tps53679", .data = (void *)tps53679},
242 	{.compatible = "ti,tps53681", .data = (void *)tps53681},
243 	{.compatible = "ti,tps53688", .data = (void *)tps53688},
244 	{}
245 };
246 MODULE_DEVICE_TABLE(of, tps53679_of_match);
247 
248 static struct i2c_driver tps53679_driver = {
249 	.driver = {
250 		.name = "tps53679",
251 		.of_match_table = of_match_ptr(tps53679_of_match),
252 	},
253 	.probe_new = tps53679_probe,
254 	.id_table = tps53679_id,
255 };
256 
257 module_i2c_driver(tps53679_driver);
258 
259 MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
260 MODULE_DESCRIPTION("PMBus driver for Texas Instruments TPS53679");
261 MODULE_LICENSE("GPL");
262