drivers/hwmon/pmbus/pxe1610.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Hardware monitoring driver for Infineon PXE1610
   4  *
   5  * Copyright (c) 2019 Facebook Inc
   6  *
   7  */
   8
   9 #include <linux/err.h>
  10 #include <linux/i2c.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include "pmbus.h"
  15
  16 #define PXE1610_NUM_PAGES 3
  17
  18 /* Identify chip parameters. */
  19 static int pxe1610_identify(struct i2c_client *client,
  20                              struct pmbus_driver_info *info)
  21 {
  22         int i;
  23
  24         for (i = 0; i < PXE1610_NUM_PAGES; i++) {
  25                 if (pmbus_check_byte_register(client, i, PMBUS_VOUT_MODE)) {
  26                         u8 vout_mode;
  27                         int ret;
  28
  29                         /* Read the register with VOUT scaling value.*/
  30                         ret = pmbus_read_byte_data(client, i, PMBUS_VOUT_MODE);
  31                         if (ret < 0)
  32                                 return ret;
  33
  34                         vout_mode = ret & GENMASK(4, 0);
  35
  36                         switch (vout_mode) {
  37                         case 1:
  38                                 info->vrm_version[i] = vr12;
  39                                 break;
  40                         case 2:
  41                                 info->vrm_version[i] = vr13;
  42                                 break;
  43                         default:
  44                                 /*
  45                                  * If prior pages are available limit operation
  46                                  * to them
  47                                  */
  48                                 if (i != 0) {
  49                                         info->pages = i;
  50                                         return 0;
  51                                 }
  52
  53                                 return -ENODEV;
  54                         }
  55                 }
  56         }
  57
  58         return 0;
  59 }
  60
  61 static struct pmbus_driver_info pxe1610_info = {
  62         .pages = PXE1610_NUM_PAGES,
  63         .format[PSC_VOLTAGE_IN] = linear,
  64         .format[PSC_VOLTAGE_OUT] = vid,
  65         .format[PSC_CURRENT_IN] = linear,
  66         .format[PSC_CURRENT_OUT] = linear,
  67         .format[PSC_TEMPERATURE] = linear,
  68         .format[PSC_POWER] = linear,
  69         .func[0] = PMBUS_HAVE_VIN
  70                 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
  71                 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
  72                 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
  73                 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
  74                 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
  75         .func[1] = PMBUS_HAVE_VIN
  76                 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
  77                 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
  78                 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
  79                 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
  80                 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
  81         .func[2] = PMBUS_HAVE_VIN
  82                 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
  83                 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
  84                 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
  85                 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
  86                 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
  87         .identify = pxe1610_identify,
  88 };
  89
  90 static int pxe1610_probe(struct i2c_client *client)
  91 {
  92         struct pmbus_driver_info *info;
  93         u8 buf[I2C_SMBUS_BLOCK_MAX];
  94         int ret;
  95
  96         if (!i2c_check_functionality(
  97                         client->adapter,
  98                         I2C_FUNC_SMBUS_READ_BYTE_DATA
  99                         | I2C_FUNC_SMBUS_READ_WORD_DATA
 100                         | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
 101                 return -ENODEV;
 102
 103         /*
 104          * By default this device doesn't boot to page 0, so set page 0
 105          * to access all pmbus registers.
 106          */
 107         i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
 108
 109         /* Read Manufacturer id */
 110         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
 111         if (ret < 0) {
 112                 dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
 113                 return ret;
 114         }
 115         if (ret != 2 || strncmp(buf, "XP", 2)) {
 116                 dev_err(&client->dev, "MFR_ID unrecognized\n");
 117                 return -ENODEV;
 118         }
 119
 120         info = devm_kmemdup(&client->dev, &pxe1610_info,
 121                             sizeof(struct pmbus_driver_info),
 122                             GFP_KERNEL);
 123         if (!info)
 124                 return -ENOMEM;
 125
 126         return pmbus_do_probe(client, info);
 127 }
 128
 129 static const struct i2c_device_id pxe1610_id[] = {
 130         {"pxe1610"},
 131         {"pxe1110"},
 132         {"pxm1310"},
 133         {}
 134 };
 135
 136 MODULE_DEVICE_TABLE(i2c, pxe1610_id);
 137
 138 static struct i2c_driver pxe1610_driver = {
 139         .driver = {
 140                         .name = "pxe1610",
 141                         },
 142         .probe = pxe1610_probe,
 143         .id_table = pxe1610_id,
 144 };
 145
 146 module_i2c_driver(pxe1610_driver);
 147
 148 MODULE_AUTHOR("Vijay Khemka <vijaykhemka@fb.com>");
 149 MODULE_DESCRIPTION("PMBus driver for Infineon PXE1610, PXE1110 and PXM1310");
 150 MODULE_LICENSE("GPL");
 151 MODULE_IMPORT_NS("PMBUS");