1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Hardware monitoring driver for Analog Devices LT7182S |
4 | * |
5 | * Copyright (c) 2022 Guenter Roeck |
6 | * |
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 | |
18 | #define LT7182S_NUM_PAGES 2 |
19 | |
20 | #define MFR_READ_EXTVCC 0xcd |
21 | #define MFR_READ_ITH 0xce |
22 | #define MFR_CONFIG_ALL_LT7182S 0xd1 |
23 | #define MFR_IOUT_PEAK 0xd7 |
24 | #define MFR_ADC_CONTROL_LT7182S 0xd8 |
25 | |
26 | #define MFR_DEBUG_TELEMETRY BIT(0) |
27 | |
28 | #define MFR_VOUT_PEAK 0xdd |
29 | #define MFR_VIN_PEAK 0xde |
30 | #define MFR_TEMPERATURE_1_PEAK 0xdf |
31 | #define MFR_CLEAR_PEAKS 0xe3 |
32 | |
33 | #define MFR_CONFIG_IEEE BIT(8) |
34 | |
35 | static int lt7182s_read_word_data(struct i2c_client *client, int page, int phase, int reg) |
36 | { |
37 | int ret; |
38 | |
39 | switch (reg) { |
40 | case PMBUS_VIRT_READ_VMON: |
41 | if (page == 0 || page == 1) |
42 | ret = pmbus_read_word_data(client, page, phase, MFR_READ_ITH); |
43 | else |
44 | ret = pmbus_read_word_data(client, page: 0, phase, MFR_READ_EXTVCC); |
45 | break; |
46 | case PMBUS_VIRT_READ_IOUT_MAX: |
47 | ret = pmbus_read_word_data(client, page, phase, MFR_IOUT_PEAK); |
48 | break; |
49 | case PMBUS_VIRT_READ_VOUT_MAX: |
50 | ret = pmbus_read_word_data(client, page, phase, MFR_VOUT_PEAK); |
51 | break; |
52 | case PMBUS_VIRT_READ_VIN_MAX: |
53 | ret = pmbus_read_word_data(client, page, phase, MFR_VIN_PEAK); |
54 | break; |
55 | case PMBUS_VIRT_READ_TEMP_MAX: |
56 | ret = pmbus_read_word_data(client, page, phase, MFR_TEMPERATURE_1_PEAK); |
57 | break; |
58 | case PMBUS_VIRT_RESET_VIN_HISTORY: |
59 | ret = (page == 0) ? 0 : -ENODATA; |
60 | break; |
61 | default: |
62 | ret = -ENODATA; |
63 | break; |
64 | } |
65 | return ret; |
66 | } |
67 | |
68 | static int lt7182s_write_word_data(struct i2c_client *client, int page, int reg, u16 word) |
69 | { |
70 | int ret; |
71 | |
72 | switch (reg) { |
73 | case PMBUS_VIRT_RESET_VIN_HISTORY: |
74 | ret = pmbus_write_byte(client, page: 0, MFR_CLEAR_PEAKS); |
75 | break; |
76 | default: |
77 | ret = -ENODATA; |
78 | break; |
79 | } |
80 | return ret; |
81 | } |
82 | |
83 | static struct pmbus_driver_info lt7182s_info = { |
84 | .pages = LT7182S_NUM_PAGES, |
85 | .format[PSC_VOLTAGE_IN] = linear, |
86 | .format[PSC_VOLTAGE_OUT] = linear, |
87 | .format[PSC_CURRENT_IN] = linear, |
88 | .format[PSC_CURRENT_OUT] = linear, |
89 | .format[PSC_TEMPERATURE] = linear, |
90 | .format[PSC_POWER] = linear, |
91 | .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | |
92 | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | |
93 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | |
94 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP, |
95 | .func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | |
96 | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | |
97 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | |
98 | PMBUS_HAVE_STATUS_INPUT, |
99 | .read_word_data = lt7182s_read_word_data, |
100 | .write_word_data = lt7182s_write_word_data, |
101 | }; |
102 | |
103 | static int lt7182s_probe(struct i2c_client *client) |
104 | { |
105 | struct device *dev = &client->dev; |
106 | struct pmbus_driver_info *info; |
107 | u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; |
108 | int ret; |
109 | |
110 | if (!i2c_check_functionality(adap: client->adapter, |
111 | I2C_FUNC_SMBUS_READ_BYTE_DATA | |
112 | I2C_FUNC_SMBUS_READ_WORD_DATA | |
113 | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) |
114 | return -ENODEV; |
115 | |
116 | ret = i2c_smbus_read_block_data(client, command: PMBUS_MFR_ID, values: buf); |
117 | if (ret < 0) { |
118 | dev_err(dev, "Failed to read PMBUS_MFR_ID\n" ); |
119 | return ret; |
120 | } |
121 | if (ret != 3 || strncmp(buf, "ADI" , 3)) { |
122 | buf[ret] = '\0'; |
123 | dev_err(dev, "Manufacturer '%s' not supported\n" , buf); |
124 | return -ENODEV; |
125 | } |
126 | |
127 | ret = i2c_smbus_read_block_data(client, command: PMBUS_MFR_MODEL, values: buf); |
128 | if (ret < 0) { |
129 | dev_err(dev, "Failed to read PMBUS_MFR_MODEL\n" ); |
130 | return ret; |
131 | } |
132 | if (ret != 7 || strncmp(buf, "LT7182S" , 7)) { |
133 | buf[ret] = '\0'; |
134 | dev_err(dev, "Model '%s' not supported\n" , buf); |
135 | return -ENODEV; |
136 | } |
137 | |
138 | info = devm_kmemdup(dev, src: <7182s_info, |
139 | len: sizeof(struct pmbus_driver_info), GFP_KERNEL); |
140 | if (!info) |
141 | return -ENOMEM; |
142 | |
143 | /* Set data format to IEEE754 if configured */ |
144 | ret = i2c_smbus_read_word_data(client, MFR_CONFIG_ALL_LT7182S); |
145 | if (ret < 0) |
146 | return ret; |
147 | if (ret & MFR_CONFIG_IEEE) { |
148 | info->format[PSC_VOLTAGE_IN] = ieee754; |
149 | info->format[PSC_VOLTAGE_OUT] = ieee754; |
150 | info->format[PSC_CURRENT_IN] = ieee754; |
151 | info->format[PSC_CURRENT_OUT] = ieee754; |
152 | info->format[PSC_TEMPERATURE] = ieee754; |
153 | info->format[PSC_POWER] = ieee754; |
154 | } |
155 | |
156 | /* Enable VMON output if configured */ |
157 | ret = i2c_smbus_read_byte_data(client, MFR_ADC_CONTROL_LT7182S); |
158 | if (ret < 0) |
159 | return ret; |
160 | if (ret & MFR_DEBUG_TELEMETRY) { |
161 | info->pages = 3; |
162 | info->func[0] |= PMBUS_HAVE_VMON; |
163 | info->func[1] |= PMBUS_HAVE_VMON; |
164 | info->func[2] = PMBUS_HAVE_VMON; |
165 | } |
166 | |
167 | return pmbus_do_probe(client, info); |
168 | } |
169 | |
170 | static const struct i2c_device_id lt7182s_id[] = { |
171 | { "lt7182s" , 0 }, |
172 | {} |
173 | }; |
174 | MODULE_DEVICE_TABLE(i2c, lt7182s_id); |
175 | |
176 | static const struct of_device_id __maybe_unused lt7182s_of_match[] = { |
177 | { .compatible = "adi,lt7182s" }, |
178 | {} |
179 | }; |
180 | |
181 | static struct i2c_driver lt7182s_driver = { |
182 | .driver = { |
183 | .name = "lt7182s" , |
184 | .of_match_table = of_match_ptr(lt7182s_of_match), |
185 | }, |
186 | .probe = lt7182s_probe, |
187 | .id_table = lt7182s_id, |
188 | }; |
189 | |
190 | module_i2c_driver(lt7182s_driver); |
191 | |
192 | MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>" ); |
193 | MODULE_DESCRIPTION("PMBus driver for Analog Devices LT7182S" ); |
194 | MODULE_LICENSE("GPL" ); |
195 | MODULE_IMPORT_NS(PMBUS); |
196 | |