1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Driver for Delta DPS920AB PSU 4 * 5 * Copyright (C) 2021 Delta Networks, Inc. 6 * Copyright (C) 2021 Sartura Ltd. 7 */ 8 9 #include <linux/debugfs.h> 10 #include <linux/i2c.h> 11 #include <linux/module.h> 12 #include <linux/of_device.h> 13 #include "pmbus.h" 14 15 struct dps920ab_data { 16 char *mfr_model; 17 char *mfr_id; 18 }; 19 20 static int dps920ab_read_word_data(struct i2c_client *client, int page, int phase, int reg) 21 { 22 /* 23 * This masks commands which are not supported. 24 * PSU advertises that all features are supported, 25 * in reality that unfortunately is not true. 26 * So enable only those that the datasheet confirms. 27 */ 28 switch (reg) { 29 case PMBUS_FAN_COMMAND_1: 30 case PMBUS_IOUT_OC_WARN_LIMIT: 31 case PMBUS_STATUS_WORD: 32 case PMBUS_READ_VIN: 33 case PMBUS_READ_IIN: 34 case PMBUS_READ_VOUT: 35 case PMBUS_READ_IOUT: 36 case PMBUS_READ_TEMPERATURE_1: 37 case PMBUS_READ_TEMPERATURE_2: 38 case PMBUS_READ_TEMPERATURE_3: 39 case PMBUS_READ_FAN_SPEED_1: 40 case PMBUS_READ_POUT: 41 case PMBUS_READ_PIN: 42 case PMBUS_MFR_VOUT_MIN: 43 case PMBUS_MFR_VOUT_MAX: 44 case PMBUS_MFR_IOUT_MAX: 45 case PMBUS_MFR_POUT_MAX: 46 return pmbus_read_word_data(client, page, phase, reg); 47 default: 48 return -ENXIO; 49 } 50 } 51 52 static int dps920ab_write_word_data(struct i2c_client *client, int page, int reg, 53 u16 word) 54 { 55 /* 56 * This masks commands which are not supported. 57 * PSU only has one R/W register and that is 58 * for the fan. 59 */ 60 switch (reg) { 61 case PMBUS_FAN_COMMAND_1: 62 return pmbus_write_word_data(client, page, reg, word); 63 default: 64 return -EACCES; 65 } 66 } 67 68 static struct pmbus_driver_info dps920ab_info = { 69 .pages = 1, 70 71 .format[PSC_VOLTAGE_IN] = linear, 72 .format[PSC_VOLTAGE_OUT] = linear, 73 .format[PSC_CURRENT_IN] = linear, 74 .format[PSC_CURRENT_OUT] = linear, 75 .format[PSC_POWER] = linear, 76 .format[PSC_FAN] = linear, 77 .format[PSC_TEMPERATURE] = linear, 78 79 .func[0] = 80 PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | 81 PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | 82 PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 | 83 PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 | 84 PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | 85 PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP, 86 .read_word_data = dps920ab_read_word_data, 87 .write_word_data = dps920ab_write_word_data, 88 }; 89 90 static int dps920ab_mfr_id_show(struct seq_file *s, void *data) 91 { 92 struct dps920ab_data *priv = s->private; 93 94 seq_printf(s, "%s\n", priv->mfr_id); 95 96 return 0; 97 } 98 99 DEFINE_SHOW_ATTRIBUTE(dps920ab_mfr_id); 100 101 static int dps920ab_mfr_model_show(struct seq_file *s, void *data) 102 { 103 struct dps920ab_data *priv = s->private; 104 105 seq_printf(s, "%s\n", priv->mfr_model); 106 107 return 0; 108 } 109 110 DEFINE_SHOW_ATTRIBUTE(dps920ab_mfr_model); 111 112 static void dps920ab_init_debugfs(struct dps920ab_data *data, struct i2c_client *client) 113 { 114 struct dentry *debugfs_dir; 115 struct dentry *root; 116 117 root = pmbus_get_debugfs_dir(client); 118 if (!root) 119 return; 120 121 debugfs_dir = debugfs_create_dir(client->name, root); 122 123 debugfs_create_file("mfr_id", 124 0400, 125 debugfs_dir, 126 data, 127 &dps920ab_mfr_id_fops); 128 129 debugfs_create_file("mfr_model", 130 0400, 131 debugfs_dir, 132 data, 133 &dps920ab_mfr_model_fops); 134 } 135 136 static int dps920ab_probe(struct i2c_client *client) 137 { 138 u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; 139 struct dps920ab_data *data; 140 int ret; 141 142 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL); 143 if (!data) 144 return -ENOMEM; 145 146 ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf); 147 if (ret < 0) { 148 dev_err(&client->dev, "Failed to read Manufacturer ID\n"); 149 return ret; 150 } 151 152 buf[ret] = '\0'; 153 if (ret != 5 || strncmp(buf, "DELTA", 5)) { 154 buf[ret] = '\0'; 155 dev_err(&client->dev, "Unsupported Manufacturer ID '%s'\n", buf); 156 return -ENODEV; 157 } 158 data->mfr_id = devm_kstrdup(&client->dev, buf, GFP_KERNEL); 159 if (!data->mfr_id) 160 return -ENOMEM; 161 162 ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); 163 if (ret < 0) { 164 dev_err(&client->dev, "Failed to read Manufacturer Model\n"); 165 return ret; 166 } 167 168 buf[ret] = '\0'; 169 if (ret != 11 || strncmp(buf, "DPS-920AB", 9)) { 170 dev_err(&client->dev, "Unsupported Manufacturer Model '%s'\n", buf); 171 return -ENODEV; 172 } 173 data->mfr_model = devm_kstrdup(&client->dev, buf, GFP_KERNEL); 174 if (!data->mfr_model) 175 return -ENOMEM; 176 177 ret = pmbus_do_probe(client, &dps920ab_info); 178 if (ret) 179 return ret; 180 181 dps920ab_init_debugfs(data, client); 182 183 return 0; 184 } 185 186 static const struct of_device_id __maybe_unused dps920ab_of_match[] = { 187 { .compatible = "delta,dps920ab", }, 188 {} 189 }; 190 191 MODULE_DEVICE_TABLE(of, dps920ab_of_match); 192 193 static struct i2c_driver dps920ab_driver = { 194 .driver = { 195 .name = "dps920ab", 196 .of_match_table = of_match_ptr(dps920ab_of_match), 197 }, 198 .probe = dps920ab_probe, 199 }; 200 201 module_i2c_driver(dps920ab_driver); 202 203 MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>"); 204 MODULE_DESCRIPTION("PMBus driver for Delta DPS920AB PSU"); 205 MODULE_LICENSE("GPL"); 206 MODULE_IMPORT_NS(PMBUS); 207