1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * MEN 14F021P00 Board Management Controller (BMC) hwmon driver. 4 * 5 * This is the core hwmon driver of the MEN 14F021P00 BMC. 6 * The BMC monitors the board voltages which can be access with this 7 * driver through sysfs. 8 * 9 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH 10 */ 11 12 #include <linux/module.h> 13 #include <linux/kernel.h> 14 #include <linux/platform_device.h> 15 #include <linux/hwmon.h> 16 #include <linux/hwmon-sysfs.h> 17 #include <linux/jiffies.h> 18 #include <linux/slab.h> 19 #include <linux/i2c.h> 20 #include <linux/err.h> 21 22 #define DRV_NAME "menf21bmc_hwmon" 23 24 #define BMC_VOLT_COUNT 5 25 #define MENF21BMC_V33 0 26 #define MENF21BMC_V5 1 27 #define MENF21BMC_V12 2 28 #define MENF21BMC_V5_SB 3 29 #define MENF21BMC_VBAT 4 30 31 #define IDX_TO_VOLT_MIN_CMD(idx) (0x40 + idx) 32 #define IDX_TO_VOLT_MAX_CMD(idx) (0x50 + idx) 33 #define IDX_TO_VOLT_INP_CMD(idx) (0x60 + idx) 34 35 struct menf21bmc_hwmon { 36 bool valid; 37 struct i2c_client *i2c_client; 38 unsigned long last_update; 39 int in_val[BMC_VOLT_COUNT]; 40 int in_min[BMC_VOLT_COUNT]; 41 int in_max[BMC_VOLT_COUNT]; 42 }; 43 44 static const char *const input_names[] = { 45 [MENF21BMC_V33] = "MON_3_3V", 46 [MENF21BMC_V5] = "MON_5V", 47 [MENF21BMC_V12] = "MON_12V", 48 [MENF21BMC_V5_SB] = "5V_STANDBY", 49 [MENF21BMC_VBAT] = "VBAT" 50 }; 51 52 static struct menf21bmc_hwmon *menf21bmc_hwmon_update(struct device *dev) 53 { 54 int i; 55 int val; 56 struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev); 57 struct menf21bmc_hwmon *data_ret = drv_data; 58 59 if (time_after(jiffies, drv_data->last_update + HZ) 60 || !drv_data->valid) { 61 for (i = 0; i < BMC_VOLT_COUNT; i++) { 62 val = i2c_smbus_read_word_data(drv_data->i2c_client, 63 IDX_TO_VOLT_INP_CMD(i)); 64 if (val < 0) { 65 data_ret = ERR_PTR(val); 66 goto abort; 67 } 68 drv_data->in_val[i] = val; 69 } 70 drv_data->last_update = jiffies; 71 drv_data->valid = true; 72 } 73 abort: 74 return data_ret; 75 } 76 77 static int menf21bmc_hwmon_get_volt_limits(struct menf21bmc_hwmon *drv_data) 78 { 79 int i, val; 80 81 for (i = 0; i < BMC_VOLT_COUNT; i++) { 82 val = i2c_smbus_read_word_data(drv_data->i2c_client, 83 IDX_TO_VOLT_MIN_CMD(i)); 84 if (val < 0) 85 return val; 86 87 drv_data->in_min[i] = val; 88 89 val = i2c_smbus_read_word_data(drv_data->i2c_client, 90 IDX_TO_VOLT_MAX_CMD(i)); 91 if (val < 0) 92 return val; 93 94 drv_data->in_max[i] = val; 95 } 96 return 0; 97 } 98 99 static ssize_t 100 label_show(struct device *dev, struct device_attribute *devattr, char *buf) 101 { 102 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 103 104 return sprintf(buf, "%s\n", input_names[attr->index]); 105 } 106 107 static ssize_t 108 in_show(struct device *dev, struct device_attribute *devattr, char *buf) 109 { 110 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 111 struct menf21bmc_hwmon *drv_data = menf21bmc_hwmon_update(dev); 112 113 if (IS_ERR(drv_data)) 114 return PTR_ERR(drv_data); 115 116 return sprintf(buf, "%d\n", drv_data->in_val[attr->index]); 117 } 118 119 static ssize_t 120 min_show(struct device *dev, struct device_attribute *devattr, char *buf) 121 { 122 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 123 struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev); 124 125 return sprintf(buf, "%d\n", drv_data->in_min[attr->index]); 126 } 127 128 static ssize_t 129 max_show(struct device *dev, struct device_attribute *devattr, char *buf) 130 { 131 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 132 struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev); 133 134 return sprintf(buf, "%d\n", drv_data->in_max[attr->index]); 135 } 136 137 static SENSOR_DEVICE_ATTR_RO(in0_input, in, 0); 138 static SENSOR_DEVICE_ATTR_RO(in0_min, min, 0); 139 static SENSOR_DEVICE_ATTR_RO(in0_max, max, 0); 140 static SENSOR_DEVICE_ATTR_RO(in0_label, label, 0); 141 static SENSOR_DEVICE_ATTR_RO(in1_input, in, 1); 142 static SENSOR_DEVICE_ATTR_RO(in1_min, min, 1); 143 static SENSOR_DEVICE_ATTR_RO(in1_max, max, 1); 144 static SENSOR_DEVICE_ATTR_RO(in1_label, label, 1); 145 static SENSOR_DEVICE_ATTR_RO(in2_input, in, 2); 146 static SENSOR_DEVICE_ATTR_RO(in2_min, min, 2); 147 static SENSOR_DEVICE_ATTR_RO(in2_max, max, 2); 148 static SENSOR_DEVICE_ATTR_RO(in2_label, label, 2); 149 static SENSOR_DEVICE_ATTR_RO(in3_input, in, 3); 150 static SENSOR_DEVICE_ATTR_RO(in3_min, min, 3); 151 static SENSOR_DEVICE_ATTR_RO(in3_max, max, 3); 152 static SENSOR_DEVICE_ATTR_RO(in3_label, label, 3); 153 static SENSOR_DEVICE_ATTR_RO(in4_input, in, 4); 154 static SENSOR_DEVICE_ATTR_RO(in4_min, min, 4); 155 static SENSOR_DEVICE_ATTR_RO(in4_max, max, 4); 156 static SENSOR_DEVICE_ATTR_RO(in4_label, label, 4); 157 158 static struct attribute *menf21bmc_hwmon_attrs[] = { 159 &sensor_dev_attr_in0_input.dev_attr.attr, 160 &sensor_dev_attr_in0_min.dev_attr.attr, 161 &sensor_dev_attr_in0_max.dev_attr.attr, 162 &sensor_dev_attr_in0_label.dev_attr.attr, 163 164 &sensor_dev_attr_in1_input.dev_attr.attr, 165 &sensor_dev_attr_in1_min.dev_attr.attr, 166 &sensor_dev_attr_in1_max.dev_attr.attr, 167 &sensor_dev_attr_in1_label.dev_attr.attr, 168 169 &sensor_dev_attr_in2_input.dev_attr.attr, 170 &sensor_dev_attr_in2_min.dev_attr.attr, 171 &sensor_dev_attr_in2_max.dev_attr.attr, 172 &sensor_dev_attr_in2_label.dev_attr.attr, 173 174 &sensor_dev_attr_in3_input.dev_attr.attr, 175 &sensor_dev_attr_in3_min.dev_attr.attr, 176 &sensor_dev_attr_in3_max.dev_attr.attr, 177 &sensor_dev_attr_in3_label.dev_attr.attr, 178 179 &sensor_dev_attr_in4_input.dev_attr.attr, 180 &sensor_dev_attr_in4_min.dev_attr.attr, 181 &sensor_dev_attr_in4_max.dev_attr.attr, 182 &sensor_dev_attr_in4_label.dev_attr.attr, 183 NULL 184 }; 185 186 ATTRIBUTE_GROUPS(menf21bmc_hwmon); 187 188 static int menf21bmc_hwmon_probe(struct platform_device *pdev) 189 { 190 int ret; 191 struct menf21bmc_hwmon *drv_data; 192 struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent); 193 struct device *hwmon_dev; 194 195 drv_data = devm_kzalloc(&pdev->dev, sizeof(struct menf21bmc_hwmon), 196 GFP_KERNEL); 197 if (!drv_data) 198 return -ENOMEM; 199 200 drv_data->i2c_client = i2c_client; 201 202 ret = menf21bmc_hwmon_get_volt_limits(drv_data); 203 if (ret) { 204 dev_err(&pdev->dev, "failed to read sensor limits"); 205 return ret; 206 } 207 208 hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, 209 "menf21bmc", drv_data, 210 menf21bmc_hwmon_groups); 211 if (IS_ERR(hwmon_dev)) 212 return PTR_ERR(hwmon_dev); 213 214 dev_info(&pdev->dev, "MEN 14F021P00 BMC hwmon device enabled"); 215 216 return 0; 217 } 218 219 static struct platform_driver menf21bmc_hwmon = { 220 .probe = menf21bmc_hwmon_probe, 221 .driver = { 222 .name = DRV_NAME, 223 }, 224 }; 225 226 module_platform_driver(menf21bmc_hwmon); 227 228 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>"); 229 MODULE_DESCRIPTION("MEN 14F021P00 BMC hwmon"); 230 MODULE_LICENSE("GPL v2"); 231 MODULE_ALIAS("platform:menf21bmc_hwmon"); 232