Neelesh Gupta | 24c1aa8 | 2014-07-08 14:38:38 +0530 | [diff] [blame] | 1 | /* |
| 2 | * IBM PowerNV platform sensors for temperature/fan/voltage/power |
| 3 | * Copyright (C) 2014 IBM |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version 2 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program. |
| 17 | */ |
| 18 | |
| 19 | #define DRVNAME "ibmpowernv" |
| 20 | #define pr_fmt(fmt) DRVNAME ": " fmt |
| 21 | |
| 22 | #include <linux/init.h> |
| 23 | #include <linux/module.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/hwmon.h> |
| 26 | #include <linux/hwmon-sysfs.h> |
| 27 | #include <linux/of.h> |
| 28 | #include <linux/slab.h> |
| 29 | |
| 30 | #include <linux/platform_device.h> |
| 31 | #include <asm/opal.h> |
| 32 | #include <linux/err.h> |
| 33 | |
| 34 | #define MAX_ATTR_LEN 32 |
| 35 | |
| 36 | /* Sensor suffix name from DT */ |
| 37 | #define DT_FAULT_ATTR_SUFFIX "faulted" |
| 38 | #define DT_DATA_ATTR_SUFFIX "data" |
| 39 | #define DT_THRESHOLD_ATTR_SUFFIX "thrs" |
| 40 | |
| 41 | /* |
| 42 | * Enumerates all the types of sensors in the POWERNV platform and does index |
| 43 | * into 'struct sensor_group' |
| 44 | */ |
| 45 | enum sensors { |
| 46 | FAN, |
| 47 | AMBIENT_TEMP, |
| 48 | POWER_SUPPLY, |
| 49 | POWER_INPUT, |
| 50 | MAX_SENSOR_TYPE, |
| 51 | }; |
| 52 | |
| 53 | static struct sensor_group { |
| 54 | const char *name; |
| 55 | const char *compatible; |
| 56 | struct attribute_group group; |
| 57 | u32 attr_count; |
| 58 | } sensor_groups[] = { |
| 59 | {"fan", "ibm,opal-sensor-cooling-fan"}, |
| 60 | {"temp", "ibm,opal-sensor-amb-temp"}, |
| 61 | {"in", "ibm,opal-sensor-power-supply"}, |
| 62 | {"power", "ibm,opal-sensor-power"} |
| 63 | }; |
| 64 | |
| 65 | struct sensor_data { |
| 66 | u32 id; /* An opaque id of the firmware for each sensor */ |
| 67 | enum sensors type; |
| 68 | char name[MAX_ATTR_LEN]; |
| 69 | struct device_attribute dev_attr; |
| 70 | }; |
| 71 | |
| 72 | struct platform_data { |
| 73 | const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1]; |
| 74 | u32 sensors_count; /* Total count of sensors from each group */ |
| 75 | }; |
| 76 | |
| 77 | /* Platform device representing all the ibmpowernv sensors */ |
| 78 | static struct platform_device *pdevice; |
| 79 | |
| 80 | static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr, |
| 81 | char *buf) |
| 82 | { |
| 83 | struct sensor_data *sdata = container_of(devattr, struct sensor_data, |
| 84 | dev_attr); |
| 85 | ssize_t ret; |
| 86 | u32 x; |
| 87 | |
| 88 | ret = opal_get_sensor_data(sdata->id, &x); |
| 89 | if (ret) |
| 90 | return ret; |
| 91 | |
| 92 | /* Convert temperature to milli-degrees */ |
| 93 | if (sdata->type == AMBIENT_TEMP) |
| 94 | x *= 1000; |
| 95 | /* Convert power to micro-watts */ |
| 96 | else if (sdata->type == POWER_INPUT) |
| 97 | x *= 1000000; |
| 98 | |
| 99 | return sprintf(buf, "%u\n", x); |
| 100 | } |
| 101 | |
| 102 | static int __init get_sensor_index_attr(const char *name, u32 *index, |
| 103 | char *attr) |
| 104 | { |
| 105 | char *hash_pos = strchr(name, '#'); |
| 106 | char buf[8] = { 0 }; |
| 107 | char *dash_pos; |
| 108 | u32 copy_len; |
| 109 | int err; |
| 110 | |
| 111 | if (!hash_pos) |
| 112 | return -EINVAL; |
| 113 | |
| 114 | dash_pos = strchr(hash_pos, '-'); |
| 115 | if (!dash_pos) |
| 116 | return -EINVAL; |
| 117 | |
| 118 | copy_len = dash_pos - hash_pos - 1; |
| 119 | if (copy_len >= sizeof(buf)) |
| 120 | return -EINVAL; |
| 121 | |
| 122 | strncpy(buf, hash_pos + 1, copy_len); |
| 123 | |
| 124 | err = kstrtou32(buf, 10, index); |
| 125 | if (err) |
| 126 | return err; |
| 127 | |
| 128 | strncpy(attr, dash_pos + 1, MAX_ATTR_LEN); |
| 129 | |
| 130 | return 0; |
| 131 | } |
| 132 | |
| 133 | /* |
| 134 | * This function translates the DT node name into the 'hwmon' attribute name. |
| 135 | * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc. |
| 136 | * which need to be mapped as fan2_input, temp1_max respectively before |
| 137 | * populating them inside hwmon device class. |
| 138 | */ |
| 139 | static int __init create_hwmon_attr_name(struct device *dev, enum sensors type, |
| 140 | const char *node_name, |
| 141 | char *hwmon_attr_name) |
| 142 | { |
| 143 | char attr_suffix[MAX_ATTR_LEN]; |
| 144 | char *attr_name; |
| 145 | u32 index; |
| 146 | int err; |
| 147 | |
| 148 | err = get_sensor_index_attr(node_name, &index, attr_suffix); |
| 149 | if (err) { |
| 150 | dev_err(dev, "Sensor device node name '%s' is invalid\n", |
| 151 | node_name); |
| 152 | return err; |
| 153 | } |
| 154 | |
| 155 | if (!strcmp(attr_suffix, DT_FAULT_ATTR_SUFFIX)) { |
| 156 | attr_name = "fault"; |
| 157 | } else if (!strcmp(attr_suffix, DT_DATA_ATTR_SUFFIX)) { |
| 158 | attr_name = "input"; |
| 159 | } else if (!strcmp(attr_suffix, DT_THRESHOLD_ATTR_SUFFIX)) { |
| 160 | if (type == AMBIENT_TEMP) |
| 161 | attr_name = "max"; |
| 162 | else if (type == FAN) |
| 163 | attr_name = "min"; |
| 164 | else |
| 165 | return -ENOENT; |
| 166 | } else { |
| 167 | return -ENOENT; |
| 168 | } |
| 169 | |
| 170 | snprintf(hwmon_attr_name, MAX_ATTR_LEN, "%s%d_%s", |
| 171 | sensor_groups[type].name, index, attr_name); |
| 172 | return 0; |
| 173 | } |
| 174 | |
| 175 | static int __init populate_attr_groups(struct platform_device *pdev) |
| 176 | { |
| 177 | struct platform_data *pdata = platform_get_drvdata(pdev); |
| 178 | const struct attribute_group **pgroups = pdata->attr_groups; |
| 179 | struct device_node *opal, *np; |
| 180 | enum sensors type; |
| 181 | |
| 182 | opal = of_find_node_by_path("/ibm,opal/sensors"); |
| 183 | if (!opal) { |
| 184 | dev_err(&pdev->dev, "Opal node 'sensors' not found\n"); |
| 185 | return -ENODEV; |
| 186 | } |
| 187 | |
| 188 | for_each_child_of_node(opal, np) { |
| 189 | if (np->name == NULL) |
| 190 | continue; |
| 191 | |
| 192 | for (type = 0; type < MAX_SENSOR_TYPE; type++) |
| 193 | if (of_device_is_compatible(np, |
| 194 | sensor_groups[type].compatible)) { |
| 195 | sensor_groups[type].attr_count++; |
| 196 | break; |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | of_node_put(opal); |
| 201 | |
| 202 | for (type = 0; type < MAX_SENSOR_TYPE; type++) { |
| 203 | sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev, |
| 204 | sizeof(struct attribute *) * |
| 205 | (sensor_groups[type].attr_count + 1), |
| 206 | GFP_KERNEL); |
| 207 | if (!sensor_groups[type].group.attrs) |
| 208 | return -ENOMEM; |
| 209 | |
| 210 | pgroups[type] = &sensor_groups[type].group; |
| 211 | pdata->sensors_count += sensor_groups[type].attr_count; |
| 212 | sensor_groups[type].attr_count = 0; |
| 213 | } |
| 214 | |
| 215 | return 0; |
| 216 | } |
| 217 | |
| 218 | /* |
| 219 | * Iterate through the device tree for each child of 'sensors' node, create |
| 220 | * a sysfs attribute file, the file is named by translating the DT node name |
| 221 | * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max |
| 222 | * etc.. |
| 223 | */ |
| 224 | static int __init create_device_attrs(struct platform_device *pdev) |
| 225 | { |
| 226 | struct platform_data *pdata = platform_get_drvdata(pdev); |
| 227 | const struct attribute_group **pgroups = pdata->attr_groups; |
| 228 | struct device_node *opal, *np; |
| 229 | struct sensor_data *sdata; |
Axel Lin | 18d03f3 | 2014-08-01 12:38:47 +0800 | [diff] [blame] | 230 | u32 sensor_id; |
Neelesh Gupta | 24c1aa8 | 2014-07-08 14:38:38 +0530 | [diff] [blame] | 231 | enum sensors type; |
| 232 | u32 count = 0; |
| 233 | int err = 0; |
| 234 | |
| 235 | opal = of_find_node_by_path("/ibm,opal/sensors"); |
| 236 | sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata), |
| 237 | GFP_KERNEL); |
| 238 | if (!sdata) { |
| 239 | err = -ENOMEM; |
| 240 | goto exit_put_node; |
| 241 | } |
| 242 | |
| 243 | for_each_child_of_node(opal, np) { |
| 244 | if (np->name == NULL) |
| 245 | continue; |
| 246 | |
| 247 | for (type = 0; type < MAX_SENSOR_TYPE; type++) |
| 248 | if (of_device_is_compatible(np, |
| 249 | sensor_groups[type].compatible)) |
| 250 | break; |
| 251 | |
| 252 | if (type == MAX_SENSOR_TYPE) |
| 253 | continue; |
| 254 | |
Axel Lin | 18d03f3 | 2014-08-01 12:38:47 +0800 | [diff] [blame] | 255 | if (of_property_read_u32(np, "sensor-id", &sensor_id)) { |
Neelesh Gupta | 24c1aa8 | 2014-07-08 14:38:38 +0530 | [diff] [blame] | 256 | dev_info(&pdev->dev, |
| 257 | "'sensor-id' missing in the node '%s'\n", |
| 258 | np->name); |
| 259 | continue; |
| 260 | } |
| 261 | |
Axel Lin | 18d03f3 | 2014-08-01 12:38:47 +0800 | [diff] [blame] | 262 | sdata[count].id = sensor_id; |
Neelesh Gupta | 24c1aa8 | 2014-07-08 14:38:38 +0530 | [diff] [blame] | 263 | sdata[count].type = type; |
| 264 | err = create_hwmon_attr_name(&pdev->dev, type, np->name, |
| 265 | sdata[count].name); |
| 266 | if (err) |
| 267 | goto exit_put_node; |
| 268 | |
| 269 | sysfs_attr_init(&sdata[count].dev_attr.attr); |
| 270 | sdata[count].dev_attr.attr.name = sdata[count].name; |
| 271 | sdata[count].dev_attr.attr.mode = S_IRUGO; |
| 272 | sdata[count].dev_attr.show = show_sensor; |
| 273 | |
| 274 | pgroups[type]->attrs[sensor_groups[type].attr_count++] = |
| 275 | &sdata[count++].dev_attr.attr; |
| 276 | } |
| 277 | |
| 278 | exit_put_node: |
| 279 | of_node_put(opal); |
| 280 | return err; |
| 281 | } |
| 282 | |
| 283 | static int __init ibmpowernv_probe(struct platform_device *pdev) |
| 284 | { |
| 285 | struct platform_data *pdata; |
| 286 | struct device *hwmon_dev; |
| 287 | int err; |
| 288 | |
| 289 | pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); |
| 290 | if (!pdata) |
| 291 | return -ENOMEM; |
| 292 | |
| 293 | platform_set_drvdata(pdev, pdata); |
| 294 | pdata->sensors_count = 0; |
| 295 | err = populate_attr_groups(pdev); |
| 296 | if (err) |
| 297 | return err; |
| 298 | |
| 299 | /* Create sysfs attribute data for each sensor found in the DT */ |
| 300 | err = create_device_attrs(pdev); |
| 301 | if (err) |
| 302 | return err; |
| 303 | |
| 304 | /* Finally, register with hwmon */ |
| 305 | hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME, |
| 306 | pdata, |
| 307 | pdata->attr_groups); |
| 308 | |
| 309 | return PTR_ERR_OR_ZERO(hwmon_dev); |
| 310 | } |
| 311 | |
| 312 | static struct platform_driver ibmpowernv_driver = { |
| 313 | .driver = { |
| 314 | .owner = THIS_MODULE, |
| 315 | .name = DRVNAME, |
| 316 | }, |
| 317 | }; |
| 318 | |
| 319 | static int __init ibmpowernv_init(void) |
| 320 | { |
| 321 | int err; |
| 322 | |
| 323 | pdevice = platform_device_alloc(DRVNAME, 0); |
| 324 | if (!pdevice) { |
| 325 | pr_err("Device allocation failed\n"); |
| 326 | err = -ENOMEM; |
| 327 | goto exit; |
| 328 | } |
| 329 | |
| 330 | err = platform_device_add(pdevice); |
| 331 | if (err) { |
| 332 | pr_err("Device addition failed (%d)\n", err); |
| 333 | goto exit_device_put; |
| 334 | } |
| 335 | |
| 336 | err = platform_driver_probe(&ibmpowernv_driver, ibmpowernv_probe); |
| 337 | if (err) { |
| 338 | pr_err("Platfrom driver probe failed\n"); |
| 339 | goto exit_device_del; |
| 340 | } |
| 341 | |
| 342 | return 0; |
| 343 | |
| 344 | exit_device_del: |
| 345 | platform_device_del(pdevice); |
| 346 | exit_device_put: |
| 347 | platform_device_put(pdevice); |
| 348 | exit: |
| 349 | return err; |
| 350 | } |
| 351 | |
| 352 | static void __exit ibmpowernv_exit(void) |
| 353 | { |
| 354 | platform_driver_unregister(&ibmpowernv_driver); |
| 355 | platform_device_unregister(pdevice); |
| 356 | } |
| 357 | |
| 358 | MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>"); |
| 359 | MODULE_DESCRIPTION("IBM POWERNV platform sensors"); |
| 360 | MODULE_LICENSE("GPL"); |
| 361 | |
| 362 | module_init(ibmpowernv_init); |
| 363 | module_exit(ibmpowernv_exit); |