xref: /openbmc/linux/drivers/hwmon/pmbus/tps53679.c (revision c6fddb28)
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 int tps53679_identify_mode(struct i2c_client *client,
38 				  struct pmbus_driver_info *info)
39 {
40 	u8 vout_params;
41 	int i, ret;
42 
43 	for (i = 0; i < info->pages; i++) {
44 		/* Read the register with VOUT scaling value.*/
45 		ret = pmbus_read_byte_data(client, i, PMBUS_VOUT_MODE);
46 		if (ret < 0)
47 			return ret;
48 
49 		vout_params = ret & GENMASK(4, 0);
50 
51 		switch (vout_params) {
52 		case TPS53679_PROT_VR13_10MV:
53 		case TPS53679_PROT_VR12_5_10MV:
54 			info->vrm_version[i] = vr13;
55 			break;
56 		case TPS53679_PROT_VR13_5MV:
57 		case TPS53679_PROT_VR12_5MV:
58 		case TPS53679_PROT_IMVP8_5MV:
59 			info->vrm_version[i] = vr12;
60 			break;
61 		default:
62 			return -EINVAL;
63 		}
64 	}
65 
66 	return 0;
67 }
68 
69 static int tps53679_identify_phases(struct i2c_client *client,
70 				    struct pmbus_driver_info *info)
71 {
72 	int ret;
73 
74 	/* On TPS53681, only channel A provides per-phase output current */
75 	ret = pmbus_read_byte_data(client, 0, TPS53681_MFR_SPECIFIC_20);
76 	if (ret < 0)
77 		return ret;
78 	info->phases[0] = (ret & 0x07) + 1;
79 
80 	return 0;
81 }
82 
83 static int tps53679_identify_chip(struct i2c_client *client,
84 				  u8 revision, u16 id)
85 {
86 	u8 buf[I2C_SMBUS_BLOCK_MAX];
87 	int ret;
88 
89 	ret = pmbus_read_byte_data(client, 0, PMBUS_REVISION);
90 	if (ret < 0)
91 		return ret;
92 	if (ret != revision) {
93 		dev_err(&client->dev, "Unexpected PMBus revision 0x%x\n", ret);
94 		return -ENODEV;
95 	}
96 
97 	ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf);
98 	if (ret < 0)
99 		return ret;
100 	if (ret != 1 || buf[0] != id) {
101 		dev_err(&client->dev, "Unexpected device ID 0x%x\n", buf[0]);
102 		return -ENODEV;
103 	}
104 	return 0;
105 }
106 
107 /*
108  * Common identification function for chips with multi-phase support.
109  * Since those chips have special configuration registers, we want to have
110  * some level of reassurance that we are really talking with the chip
111  * being probed. Check PMBus revision and chip ID.
112  */
113 static int tps53679_identify_multiphase(struct i2c_client *client,
114 					struct pmbus_driver_info *info,
115 					int pmbus_rev, int device_id)
116 {
117 	int ret;
118 
119 	ret = tps53679_identify_chip(client, pmbus_rev, device_id);
120 	if (ret < 0)
121 		return ret;
122 
123 	ret = tps53679_identify_mode(client, info);
124 	if (ret < 0)
125 		return ret;
126 
127 	return tps53679_identify_phases(client, info);
128 }
129 
130 static int tps53679_identify(struct i2c_client *client,
131 			     struct pmbus_driver_info *info)
132 {
133 	return tps53679_identify_mode(client, info);
134 }
135 
136 static int tps53681_identify(struct i2c_client *client,
137 			     struct pmbus_driver_info *info)
138 {
139 	return tps53679_identify_multiphase(client, info,
140 					    TPS53681_PMBUS_REVISION,
141 					    TPS53681_DEVICE_ID);
142 }
143 
144 static int tps53681_read_word_data(struct i2c_client *client, int page,
145 				   int phase, int reg)
146 {
147 	/*
148 	 * For reading the total output current (READ_IOUT) for all phases,
149 	 * the chip datasheet is a bit vague. It says "PHASE must be set to
150 	 * FFh to access all phases simultaneously. PHASE may also be set to
151 	 * 80h readack (!) the total phase current".
152 	 * Experiments show that the command does _not_ report the total
153 	 * current for all phases if the phase is set to 0xff. Instead, it
154 	 * appears to report the current of one of the phases. Override phase
155 	 * parameter with 0x80 when reading the total output current on page 0.
156 	 */
157 	if (reg == PMBUS_READ_IOUT && page == 0 && phase == 0xff)
158 		return pmbus_read_word_data(client, page, 0x80, reg);
159 	return -ENODATA;
160 }
161 
162 static struct pmbus_driver_info tps53679_info = {
163 	.format[PSC_VOLTAGE_IN] = linear,
164 	.format[PSC_VOLTAGE_OUT] = vid,
165 	.format[PSC_TEMPERATURE] = linear,
166 	.format[PSC_CURRENT_OUT] = linear,
167 	.format[PSC_POWER] = linear,
168 	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
169 		PMBUS_HAVE_STATUS_INPUT |
170 		PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
171 		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
172 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
173 		PMBUS_HAVE_POUT,
174 	.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
175 		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
176 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
177 		PMBUS_HAVE_POUT,
178 	.pfunc[0] = PMBUS_HAVE_IOUT,
179 	.pfunc[1] = PMBUS_HAVE_IOUT,
180 	.pfunc[2] = PMBUS_HAVE_IOUT,
181 	.pfunc[3] = PMBUS_HAVE_IOUT,
182 	.pfunc[4] = PMBUS_HAVE_IOUT,
183 	.pfunc[5] = PMBUS_HAVE_IOUT,
184 };
185 
186 static int tps53679_probe(struct i2c_client *client,
187 			  const struct i2c_device_id *id)
188 {
189 	struct device *dev = &client->dev;
190 	struct pmbus_driver_info *info;
191 	enum chips chip_id;
192 
193 	if (dev->of_node)
194 		chip_id = (enum chips)of_device_get_match_data(dev);
195 	else
196 		chip_id = id->driver_data;
197 
198 	info = devm_kmemdup(dev, &tps53679_info, sizeof(*info), GFP_KERNEL);
199 	if (!info)
200 		return -ENOMEM;
201 
202 	switch (chip_id) {
203 	case tps53647:
204 	case tps53667:
205 		info->pages = TPS53647_PAGE_NUM;
206 		info->identify = tps53679_identify;
207 		break;
208 	case tps53679:
209 	case tps53688:
210 		info->pages = TPS53679_PAGE_NUM;
211 		info->identify = tps53679_identify;
212 		break;
213 	case tps53681:
214 		info->pages = TPS53679_PAGE_NUM;
215 		info->phases[0] = 6;
216 		info->identify = tps53681_identify;
217 		info->read_word_data = tps53681_read_word_data;
218 		break;
219 	default:
220 		return -ENODEV;
221 	}
222 
223 	return pmbus_do_probe(client, id, info);
224 }
225 
226 static const struct i2c_device_id tps53679_id[] = {
227 	{"tps53647", tps53647},
228 	{"tps53667", tps53667},
229 	{"tps53679", tps53679},
230 	{"tps53681", tps53681},
231 	{"tps53688", tps53688},
232 	{}
233 };
234 
235 MODULE_DEVICE_TABLE(i2c, tps53679_id);
236 
237 static const struct of_device_id __maybe_unused tps53679_of_match[] = {
238 	{.compatible = "ti,tps53647", .data = (void *)tps53647},
239 	{.compatible = "ti,tps53667", .data = (void *)tps53667},
240 	{.compatible = "ti,tps53679", .data = (void *)tps53679},
241 	{.compatible = "ti,tps53681", .data = (void *)tps53681},
242 	{.compatible = "ti,tps53688", .data = (void *)tps53688},
243 	{}
244 };
245 MODULE_DEVICE_TABLE(of, tps53679_of_match);
246 
247 static struct i2c_driver tps53679_driver = {
248 	.driver = {
249 		.name = "tps53679",
250 		.of_match_table = of_match_ptr(tps53679_of_match),
251 	},
252 	.probe = tps53679_probe,
253 	.remove = pmbus_do_remove,
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