xref: /linux/drivers/hwmon/pmbus/mp5990.c (revision 68a052239fc4b351e961f698b824f7654a346091)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for MPS MP5990 Hot-Swap Controller
4  */
5 
6 #include <linux/i2c.h>
7 #include <linux/module.h>
8 #include <linux/of_device.h>
9 #include "pmbus.h"
10 
11 enum chips { mp5990, mp5998 };
12 
13 #define MP5990_EFUSE_CFG	(0xC4)
14 #define MP5990_VOUT_FORMAT	BIT(9)
15 
16 struct mp5990_data {
17 	struct pmbus_driver_info info;
18 	u8 vout_mode;
19 	u8 vout_linear_exponent;
20 };
21 
22 #define to_mp5990_data(x)  container_of(x, struct mp5990_data, info)
23 
24 static int mp5990_read_byte_data(struct i2c_client *client, int page, int reg)
25 {
26 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
27 	struct mp5990_data *data = to_mp5990_data(info);
28 
29 	switch (reg) {
30 	case PMBUS_VOUT_MODE:
31 		if (data->vout_mode == linear) {
32 			/*
33 			 * The VOUT format used by the chip is linear11,
34 			 * not linear16. Report that VOUT is in linear mode
35 			 * and return exponent value extracted while probing
36 			 * the chip.
37 			 */
38 			return data->vout_linear_exponent;
39 		}
40 
41 		/*
42 		 * The datasheet does not support the VOUT command,
43 		 * but the device responds with a default value of 0x17.
44 		 * In the standard, 0x17 represents linear mode.
45 		 * Therefore, we should report that VOUT is in direct
46 		 * format when the chip is configured for it.
47 		 */
48 		return PB_VOUT_MODE_DIRECT;
49 
50 	default:
51 		return -ENODATA;
52 	}
53 }
54 
55 static int mp5990_read_word_data(struct i2c_client *client, int page,
56 				 int phase, int reg)
57 {
58 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
59 	struct mp5990_data *data = to_mp5990_data(info);
60 	int ret;
61 	s32 mantissa;
62 
63 	switch (reg) {
64 	case PMBUS_READ_VOUT:
65 		ret = pmbus_read_word_data(client, page, phase, reg);
66 		if (ret < 0)
67 			return ret;
68 		/*
69 		 * Because the VOUT format used by the chip is linear11 and not
70 		 * linear16, we disregard bits[15:11]. The exponent is reported
71 		 * as part of the VOUT_MODE command.
72 		 */
73 		if (data->vout_mode == linear) {
74 			mantissa = ((s16)((ret & 0x7ff) << 5)) >> 5;
75 			ret = mantissa;
76 		}
77 		break;
78 	default:
79 		return -ENODATA;
80 	}
81 
82 	return ret;
83 }
84 
85 static struct pmbus_driver_info mp5990_info = {
86 	.pages = 1,
87 	.format[PSC_VOLTAGE_IN] = direct,
88 	.format[PSC_VOLTAGE_OUT] = direct,
89 	.format[PSC_CURRENT_OUT] = direct,
90 	.format[PSC_POWER] = direct,
91 	.format[PSC_TEMPERATURE] = direct,
92 	.m[PSC_VOLTAGE_IN] = 32,
93 	.b[PSC_VOLTAGE_IN] = 0,
94 	.R[PSC_VOLTAGE_IN] = 0,
95 	.m[PSC_VOLTAGE_OUT] = 32,
96 	.b[PSC_VOLTAGE_OUT] = 0,
97 	.R[PSC_VOLTAGE_OUT] = 0,
98 	.m[PSC_CURRENT_OUT] = 16,
99 	.b[PSC_CURRENT_OUT] = 0,
100 	.R[PSC_CURRENT_OUT] = 0,
101 	.m[PSC_POWER] = 1,
102 	.b[PSC_POWER] = 0,
103 	.R[PSC_POWER] = 0,
104 	.m[PSC_TEMPERATURE] = 1,
105 	.b[PSC_TEMPERATURE] = 0,
106 	.R[PSC_TEMPERATURE] = 0,
107 	.func[0] =
108 		PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_PIN |
109 		PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT |
110 		PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
111 	.read_byte_data = mp5990_read_byte_data,
112 	.read_word_data = mp5990_read_word_data,
113 };
114 
115 static struct pmbus_driver_info mp5998_info = {
116 	.pages = 1,
117 	.format[PSC_VOLTAGE_IN] = direct,
118 	.format[PSC_VOLTAGE_OUT] = direct,
119 	.format[PSC_CURRENT_IN] = direct,
120 	.format[PSC_CURRENT_OUT] = direct,
121 	.format[PSC_POWER] = direct,
122 	.format[PSC_TEMPERATURE] = direct,
123 	.m[PSC_VOLTAGE_IN] = 64,
124 	.b[PSC_VOLTAGE_IN] = 0,
125 	.R[PSC_VOLTAGE_IN] = 0,
126 	.m[PSC_VOLTAGE_OUT] = 64,
127 	.b[PSC_VOLTAGE_OUT] = 0,
128 	.R[PSC_VOLTAGE_OUT] = 0,
129 	.m[PSC_CURRENT_IN] = 16,
130 	.b[PSC_CURRENT_IN] = 0,
131 	.R[PSC_CURRENT_IN] = 0,
132 	.m[PSC_CURRENT_OUT] = 16,
133 	.b[PSC_CURRENT_OUT] = 0,
134 	.R[PSC_CURRENT_OUT] = 0,
135 	.m[PSC_POWER] = 2,
136 	.b[PSC_POWER] = 0,
137 	.R[PSC_POWER] = 0,
138 	.m[PSC_TEMPERATURE] = 1,
139 	.b[PSC_TEMPERATURE] = 0,
140 	.R[PSC_TEMPERATURE] = 0,
141 	.func[0] =
142 		PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
143 		PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT |
144 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_IOUT |
145 		PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
146 	.read_byte_data = mp5990_read_byte_data,
147 	.read_word_data = mp5990_read_word_data,
148 };
149 
150 static const struct i2c_device_id mp5990_id[] = {
151 	{"mp5990", mp5990},
152 	{"mp5998", mp5998},
153 	{ }
154 };
155 MODULE_DEVICE_TABLE(i2c, mp5990_id);
156 
157 static int mp5990_probe(struct i2c_client *client)
158 {
159 	struct pmbus_driver_info *info;
160 	struct mp5990_data *data;
161 	enum chips chip;
162 	int ret;
163 
164 	data = devm_kzalloc(&client->dev, sizeof(struct mp5990_data),
165 			    GFP_KERNEL);
166 	if (!data)
167 		return -ENOMEM;
168 
169 	if (client->dev.of_node)
170 		chip = (uintptr_t)of_device_get_match_data(&client->dev);
171 	else
172 		chip = i2c_match_id(mp5990_id, client)->driver_data;
173 
174 	if (chip == mp5990)
175 		memcpy(&data->info, &mp5990_info, sizeof(*info));
176 	else
177 		memcpy(&data->info, &mp5998_info, sizeof(*info));
178 	info = &data->info;
179 
180 	/* Read Vout Config */
181 	ret = i2c_smbus_read_word_data(client, MP5990_EFUSE_CFG);
182 	if (ret < 0) {
183 		dev_err(&client->dev, "Can't get vout mode.");
184 		return ret;
185 	}
186 
187 	/*
188 	 * EFUSE_CFG (0xC4) bit9=1 is linear mode, bit=0 is direct mode.
189 	 */
190 	if (ret & MP5990_VOUT_FORMAT) {
191 		data->vout_mode = linear;
192 		data->info.format[PSC_VOLTAGE_IN] = linear;
193 		data->info.format[PSC_VOLTAGE_OUT] = linear;
194 		data->info.format[PSC_CURRENT_OUT] = linear;
195 		data->info.format[PSC_POWER] = linear;
196 		if (chip == mp5998)
197 			data->info.format[PSC_CURRENT_IN] = linear;
198 
199 		ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
200 		if (ret < 0) {
201 			dev_err(&client->dev, "Can't get vout exponent.");
202 			return ret;
203 		}
204 		data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
205 	} else {
206 		data->vout_mode = direct;
207 	}
208 	return pmbus_do_probe(client, info);
209 }
210 
211 static const struct of_device_id mp5990_of_match[] = {
212 	{ .compatible = "mps,mp5990", .data = (void *)mp5990 },
213 	{ .compatible = "mps,mp5998", .data = (void *)mp5998 },
214 	{}
215 };
216 
217 static struct i2c_driver mp5990_driver = {
218 	.driver = {
219 		   .name = "mp5990",
220 		   .of_match_table = mp5990_of_match,
221 	},
222 	.probe = mp5990_probe,
223 	.id_table = mp5990_id,
224 };
225 module_i2c_driver(mp5990_driver);
226 
227 MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");
228 MODULE_DESCRIPTION("PMBus driver for MP5990 HSC");
229 MODULE_LICENSE("GPL");
230 MODULE_IMPORT_NS("PMBUS");
231