1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Hardware monitoring driver for Sony APS-379 Power Supplies 4 * 5 * Copyright 2026 Allied Telesis Labs 6 */ 7 8 #include <linux/i2c.h> 9 #include <linux/init.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/pmbus.h> 13 #include "pmbus.h" 14 15 /* 16 * The VOUT format used by the chip is linear11, not linear16. Provide a hard 17 * coded VOUT_MODE that says VOUT is in linear mode with a fixed exponent of 18 * 2^-4. 19 */ 20 #define APS_379_VOUT_MODE ((u8)(-4 & 0x1f)) 21 22 static int aps_379_read_byte_data(struct i2c_client *client, int page, int reg) 23 { 24 switch (reg) { 25 case PMBUS_VOUT_MODE: 26 return APS_379_VOUT_MODE; 27 default: 28 return -ENODATA; 29 } 30 } 31 32 /* 33 * The APS-379 uses linear11 format instead of linear16. We've reported the exponent 34 * via the PMBUS_VOUT_MODE so we just return the mantissa here. 35 */ 36 static int aps_379_read_vout(struct i2c_client *client) 37 { 38 int ret; 39 40 ret = pmbus_read_word_data(client, 0, 0xff, PMBUS_READ_VOUT); 41 if (ret < 0) 42 return ret; 43 44 return clamp_val(sign_extend32(ret & 0x7ff, 10), 0, 0x3ff); 45 } 46 47 static int aps_379_read_word_data(struct i2c_client *client, int page, int phase, int reg) 48 { 49 switch (reg) { 50 case PMBUS_VOUT_UV_WARN_LIMIT: 51 case PMBUS_VOUT_OV_WARN_LIMIT: 52 case PMBUS_VOUT_UV_FAULT_LIMIT: 53 case PMBUS_VOUT_OV_FAULT_LIMIT: 54 case PMBUS_IOUT_OC_WARN_LIMIT: 55 case PMBUS_IOUT_UC_FAULT_LIMIT: 56 case PMBUS_UT_WARN_LIMIT: 57 case PMBUS_UT_FAULT_LIMIT: 58 case PMBUS_OT_WARN_LIMIT: 59 case PMBUS_OT_FAULT_LIMIT: 60 case PMBUS_PIN_OP_WARN_LIMIT: 61 case PMBUS_POUT_OP_WARN_LIMIT: 62 case PMBUS_MFR_IIN_MAX: 63 case PMBUS_MFR_PIN_MAX: 64 case PMBUS_MFR_VOUT_MIN: 65 case PMBUS_MFR_VOUT_MAX: 66 case PMBUS_MFR_IOUT_MAX: 67 case PMBUS_MFR_POUT_MAX: 68 case PMBUS_MFR_MAX_TEMP_1: 69 /* These commands return data but it is invalid/un-documented */ 70 return -ENXIO; 71 case PMBUS_IOUT_OC_FAULT_LIMIT: 72 /* 73 * The standard requires this to be a value in Amps but it's 74 * actually a percentage of the rated output (123A for 75 * 110-240Vac, 110A for 90-100Vac) which we don't know. Ignore 76 * it rather than guessing. 77 */ 78 return -ENXIO; 79 case PMBUS_READ_VOUT: 80 return aps_379_read_vout(client); 81 default: 82 return -ENODATA; 83 } 84 } 85 86 static struct pmbus_driver_info aps_379_info = { 87 .pages = 1, 88 .format[PSC_VOLTAGE_OUT] = linear, 89 .format[PSC_CURRENT_OUT] = linear, 90 .format[PSC_POWER] = linear, 91 .format[PSC_TEMPERATURE] = linear, 92 .format[PSC_FAN] = linear, 93 .func[0] = PMBUS_HAVE_VOUT | 94 PMBUS_HAVE_IOUT | 95 PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | 96 PMBUS_HAVE_TEMP | 97 PMBUS_HAVE_FAN12, 98 .read_byte_data = aps_379_read_byte_data, 99 .read_word_data = aps_379_read_word_data, 100 }; 101 102 static const struct i2c_device_id aps_379_id[] = { 103 { "aps-379", 0 }, 104 {}, 105 }; 106 MODULE_DEVICE_TABLE(i2c, aps_379_id); 107 108 static int aps_379_probe(struct i2c_client *client) 109 { 110 struct device *dev = &client->dev; 111 u8 buf[I2C_SMBUS_BLOCK_MAX + 1] = { 0 }; 112 int ret; 113 114 if (!i2c_check_functionality(client->adapter, 115 I2C_FUNC_SMBUS_READ_BYTE_DATA 116 | I2C_FUNC_SMBUS_READ_WORD_DATA 117 | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) 118 return -ENODEV; 119 120 ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); 121 if (ret < 0) { 122 dev_err(dev, "Failed to read Manufacturer Model\n"); 123 return ret; 124 } 125 126 if (strncasecmp(buf, aps_379_id[0].name, strlen(aps_379_id[0].name)) != 0) { 127 buf[ret] = '\0'; 128 dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf); 129 return -ENODEV; 130 } 131 132 return pmbus_do_probe(client, &aps_379_info); 133 } 134 135 static const struct of_device_id __maybe_unused aps_379_of_match[] = { 136 { .compatible = "sony,aps-379" }, 137 {}, 138 }; 139 MODULE_DEVICE_TABLE(of, aps_379_of_match); 140 141 static struct i2c_driver aps_379_driver = { 142 .driver = { 143 .name = "aps-379", 144 .of_match_table = of_match_ptr(aps_379_of_match), 145 }, 146 .probe = aps_379_probe, 147 .id_table = aps_379_id, 148 }; 149 150 module_i2c_driver(aps_379_driver); 151 152 MODULE_AUTHOR("Chris Packham"); 153 MODULE_DESCRIPTION("PMBus driver for Sony APS-379"); 154 MODULE_LICENSE("GPL"); 155 MODULE_IMPORT_NS("PMBUS"); 156