1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for Gateworks System Controller Hardware Monitor module 4 * 5 * Copyright (C) 2020 Gateworks Corporation 6 */ 7 #include <linux/hwmon.h> 8 #include <linux/hwmon-sysfs.h> 9 #include <linux/mfd/gsc.h> 10 #include <linux/module.h> 11 #include <linux/of.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 #include <linux/slab.h> 15 16 #include <linux/platform_data/gsc_hwmon.h> 17 18 #define GSC_HWMON_MAX_TEMP_CH 16 19 #define GSC_HWMON_MAX_IN_CH 16 20 #define GSC_HWMON_MAX_FAN_CH 16 21 22 #define GSC_HWMON_RESOLUTION 12 23 #define GSC_HWMON_VREF 2500 24 25 struct gsc_hwmon_data { 26 struct gsc_dev *gsc; 27 struct gsc_hwmon_platform_data *pdata; 28 struct regmap *regmap; 29 const struct gsc_hwmon_channel *temp_ch[GSC_HWMON_MAX_TEMP_CH]; 30 const struct gsc_hwmon_channel *in_ch[GSC_HWMON_MAX_IN_CH]; 31 const struct gsc_hwmon_channel *fan_ch[GSC_HWMON_MAX_FAN_CH]; 32 u32 temp_config[GSC_HWMON_MAX_TEMP_CH + 1]; 33 u32 in_config[GSC_HWMON_MAX_IN_CH + 1]; 34 u32 fan_config[GSC_HWMON_MAX_FAN_CH + 1]; 35 struct hwmon_channel_info temp_info; 36 struct hwmon_channel_info in_info; 37 struct hwmon_channel_info fan_info; 38 const struct hwmon_channel_info *info[4]; 39 struct hwmon_chip_info chip; 40 }; 41 42 static const struct regmap_bus gsc_hwmon_regmap_bus = { 43 .reg_read = gsc_read, 44 .reg_write = gsc_write, 45 }; 46 47 static const struct regmap_config gsc_hwmon_regmap_config = { 48 .reg_bits = 8, 49 .val_bits = 8, 50 .cache_type = REGCACHE_NONE, 51 }; 52 53 static ssize_t pwm_auto_point_temp_show(struct device *dev, 54 struct device_attribute *devattr, 55 char *buf) 56 { 57 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 58 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 59 u8 reg = hwmon->pdata->fan_base + (2 * attr->index); 60 u8 regs[2]; 61 int ret; 62 63 ret = regmap_bulk_read(hwmon->regmap, reg, regs, 2); 64 if (ret) 65 return ret; 66 67 ret = regs[0] | regs[1] << 8; 68 return sprintf(buf, "%d\n", ret * 10); 69 } 70 71 static ssize_t pwm_auto_point_temp_store(struct device *dev, 72 struct device_attribute *devattr, 73 const char *buf, size_t count) 74 { 75 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 76 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 77 u8 reg = hwmon->pdata->fan_base + (2 * attr->index); 78 u8 regs[2]; 79 long temp; 80 int err; 81 82 if (kstrtol(buf, 10, &temp)) 83 return -EINVAL; 84 85 temp = clamp_val(temp, 0, 100000); 86 temp = DIV_ROUND_CLOSEST(temp, 100); 87 88 regs[0] = temp & 0xff; 89 regs[1] = (temp >> 8) & 0xff; 90 err = regmap_bulk_write(hwmon->regmap, reg, regs, 2); 91 if (err) 92 return err; 93 94 return count; 95 } 96 97 static ssize_t pwm_auto_point_pwm_show(struct device *dev, 98 struct device_attribute *devattr, 99 char *buf) 100 { 101 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 102 103 return sprintf(buf, "%d\n", 255 * (50 + (attr->index * 10))); 104 } 105 106 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm_auto_point_pwm, 0); 107 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, pwm_auto_point_temp, 0); 108 109 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point2_pwm, pwm_auto_point_pwm, 1); 110 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, pwm_auto_point_temp, 1); 111 112 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm_auto_point_pwm, 2); 113 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, pwm_auto_point_temp, 2); 114 115 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point4_pwm, pwm_auto_point_pwm, 3); 116 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, pwm_auto_point_temp, 3); 117 118 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm_auto_point_pwm, 4); 119 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point5_temp, pwm_auto_point_temp, 4); 120 121 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point6_pwm, pwm_auto_point_pwm, 5); 122 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point6_temp, pwm_auto_point_temp, 5); 123 124 static struct attribute *gsc_hwmon_attributes[] = { 125 &sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr, 126 &sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr, 127 &sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr, 128 &sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr, 129 &sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr, 130 &sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr, 131 &sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr, 132 &sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr, 133 &sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr, 134 &sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr, 135 &sensor_dev_attr_pwm1_auto_point6_pwm.dev_attr.attr, 136 &sensor_dev_attr_pwm1_auto_point6_temp.dev_attr.attr, 137 NULL 138 }; 139 140 static const struct attribute_group gsc_hwmon_group = { 141 .attrs = gsc_hwmon_attributes, 142 }; 143 __ATTRIBUTE_GROUPS(gsc_hwmon); 144 145 static int 146 gsc_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, 147 int channel, long *val) 148 { 149 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 150 const struct gsc_hwmon_channel *ch; 151 int sz, ret; 152 long tmp; 153 u8 buf[3]; 154 155 switch (type) { 156 case hwmon_in: 157 ch = hwmon->in_ch[channel]; 158 break; 159 case hwmon_temp: 160 ch = hwmon->temp_ch[channel]; 161 break; 162 case hwmon_fan: 163 ch = hwmon->fan_ch[channel]; 164 break; 165 default: 166 return -EOPNOTSUPP; 167 } 168 169 sz = (ch->mode == mode_voltage_24bit) ? 3 : 2; 170 ret = regmap_bulk_read(hwmon->regmap, ch->reg, buf, sz); 171 if (ret) 172 return ret; 173 174 tmp = 0; 175 while (sz-- > 0) 176 tmp |= (buf[sz] << (8 * sz)); 177 178 switch (ch->mode) { 179 case mode_temperature: 180 if (tmp > 0x8000) 181 tmp -= 0xffff; 182 tmp *= 100; /* convert to millidegrees celsius */ 183 break; 184 case mode_voltage_raw: 185 tmp = clamp_val(tmp, 0, BIT(GSC_HWMON_RESOLUTION)); 186 /* scale based on ref voltage and ADC resolution */ 187 tmp *= GSC_HWMON_VREF; 188 tmp >>= GSC_HWMON_RESOLUTION; 189 /* scale based on optional voltage divider */ 190 if (ch->vdiv[0] && ch->vdiv[1]) { 191 tmp *= (ch->vdiv[0] + ch->vdiv[1]); 192 tmp /= ch->vdiv[1]; 193 } 194 /* adjust by uV offset */ 195 tmp += ch->mvoffset; 196 break; 197 case mode_fan: 198 tmp *= 30; /* convert to revolutions per minute */ 199 break; 200 case mode_voltage_24bit: 201 case mode_voltage_16bit: 202 /* no adjustment needed */ 203 break; 204 } 205 206 *val = tmp; 207 208 return 0; 209 } 210 211 static int 212 gsc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, 213 u32 attr, int channel, const char **buf) 214 { 215 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 216 217 switch (type) { 218 case hwmon_in: 219 *buf = hwmon->in_ch[channel]->name; 220 break; 221 case hwmon_temp: 222 *buf = hwmon->temp_ch[channel]->name; 223 break; 224 case hwmon_fan: 225 *buf = hwmon->fan_ch[channel]->name; 226 break; 227 default: 228 return -ENOTSUPP; 229 } 230 231 return 0; 232 } 233 234 static umode_t 235 gsc_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr, 236 int ch) 237 { 238 return 0444; 239 } 240 241 static const struct hwmon_ops gsc_hwmon_ops = { 242 .is_visible = gsc_hwmon_is_visible, 243 .read = gsc_hwmon_read, 244 .read_string = gsc_hwmon_read_string, 245 }; 246 247 static struct gsc_hwmon_platform_data * 248 gsc_hwmon_get_devtree_pdata(struct device *dev) 249 { 250 struct gsc_hwmon_platform_data *pdata; 251 struct gsc_hwmon_channel *ch; 252 struct device_node *fan; 253 int nchannels; 254 255 nchannels = device_get_child_node_count(dev); 256 if (nchannels == 0) 257 return ERR_PTR(-ENODEV); 258 259 pdata = devm_kzalloc(dev, struct_size(pdata, channels, nchannels), 260 GFP_KERNEL); 261 if (!pdata) 262 return ERR_PTR(-ENOMEM); 263 pdata->nchannels = nchannels; 264 265 /* fan controller base address */ 266 of_node_get(dev->parent->of_node); 267 fan = of_find_compatible_node(dev->parent->of_node, NULL, "gw,gsc-fan"); 268 if (fan && of_property_read_u32(fan, "reg", &pdata->fan_base)) { 269 of_node_put(fan); 270 dev_err(dev, "fan node without base\n"); 271 return ERR_PTR(-EINVAL); 272 } 273 274 of_node_put(fan); 275 276 ch = pdata->channels; 277 /* allocate structures for channels and count instances of each type */ 278 device_for_each_child_node_scoped(dev, child) { 279 if (fwnode_property_read_string(child, "label", &ch->name)) { 280 dev_err(dev, "channel without label\n"); 281 return ERR_PTR(-EINVAL); 282 } 283 if (fwnode_property_read_u32(child, "reg", &ch->reg)) { 284 dev_err(dev, "channel without reg\n"); 285 return ERR_PTR(-EINVAL); 286 } 287 if (fwnode_property_read_u32(child, "gw,mode", &ch->mode)) { 288 dev_err(dev, "channel without mode\n"); 289 return ERR_PTR(-EINVAL); 290 } 291 if (ch->mode > mode_max) { 292 dev_err(dev, "invalid channel mode\n"); 293 return ERR_PTR(-EINVAL); 294 } 295 296 if (!fwnode_property_read_u32(child, 297 "gw,voltage-offset-microvolt", 298 &ch->mvoffset)) 299 ch->mvoffset /= 1000; 300 fwnode_property_read_u32_array(child, 301 "gw,voltage-divider-ohms", 302 ch->vdiv, ARRAY_SIZE(ch->vdiv)); 303 ch++; 304 } 305 306 return pdata; 307 } 308 309 static int gsc_hwmon_probe(struct platform_device *pdev) 310 { 311 struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent); 312 struct device *dev = &pdev->dev; 313 struct device *hwmon_dev; 314 struct gsc_hwmon_platform_data *pdata = dev_get_platdata(dev); 315 struct gsc_hwmon_data *hwmon; 316 const struct attribute_group **groups; 317 int i, i_in, i_temp, i_fan; 318 319 if (!pdata) { 320 pdata = gsc_hwmon_get_devtree_pdata(dev); 321 if (IS_ERR(pdata)) 322 return PTR_ERR(pdata); 323 } 324 325 hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL); 326 if (!hwmon) 327 return -ENOMEM; 328 hwmon->gsc = gsc; 329 hwmon->pdata = pdata; 330 331 hwmon->regmap = devm_regmap_init(dev, &gsc_hwmon_regmap_bus, 332 gsc->i2c_hwmon, 333 &gsc_hwmon_regmap_config); 334 if (IS_ERR(hwmon->regmap)) 335 return PTR_ERR(hwmon->regmap); 336 337 for (i = 0, i_in = 0, i_temp = 0, i_fan = 0; i < hwmon->pdata->nchannels; i++) { 338 const struct gsc_hwmon_channel *ch = &pdata->channels[i]; 339 340 switch (ch->mode) { 341 case mode_temperature: 342 if (i_temp == GSC_HWMON_MAX_TEMP_CH) { 343 dev_err(gsc->dev, "too many temp channels\n"); 344 return -EINVAL; 345 } 346 hwmon->temp_ch[i_temp] = ch; 347 hwmon->temp_config[i_temp] = HWMON_T_INPUT | 348 HWMON_T_LABEL; 349 i_temp++; 350 break; 351 case mode_fan: 352 if (i_fan == GSC_HWMON_MAX_FAN_CH) { 353 dev_err(gsc->dev, "too many fan channels\n"); 354 return -EINVAL; 355 } 356 hwmon->fan_ch[i_fan] = ch; 357 hwmon->fan_config[i_fan] = HWMON_F_INPUT | 358 HWMON_F_LABEL; 359 i_fan++; 360 break; 361 case mode_voltage_24bit: 362 case mode_voltage_16bit: 363 case mode_voltage_raw: 364 if (i_in == GSC_HWMON_MAX_IN_CH) { 365 dev_err(gsc->dev, "too many input channels\n"); 366 return -EINVAL; 367 } 368 hwmon->in_ch[i_in] = ch; 369 hwmon->in_config[i_in] = 370 HWMON_I_INPUT | HWMON_I_LABEL; 371 i_in++; 372 break; 373 default: 374 dev_err(gsc->dev, "invalid mode: %d\n", ch->mode); 375 return -EINVAL; 376 } 377 } 378 379 /* setup config structures */ 380 hwmon->chip.ops = &gsc_hwmon_ops; 381 hwmon->chip.info = hwmon->info; 382 hwmon->info[0] = &hwmon->temp_info; 383 hwmon->info[1] = &hwmon->in_info; 384 hwmon->info[2] = &hwmon->fan_info; 385 hwmon->temp_info.type = hwmon_temp; 386 hwmon->temp_info.config = hwmon->temp_config; 387 hwmon->in_info.type = hwmon_in; 388 hwmon->in_info.config = hwmon->in_config; 389 hwmon->fan_info.type = hwmon_fan; 390 hwmon->fan_info.config = hwmon->fan_config; 391 392 groups = pdata->fan_base ? gsc_hwmon_groups : NULL; 393 hwmon_dev = devm_hwmon_device_register_with_info(dev, 394 KBUILD_MODNAME, hwmon, 395 &hwmon->chip, groups); 396 return PTR_ERR_OR_ZERO(hwmon_dev); 397 } 398 399 static const struct of_device_id gsc_hwmon_of_match[] = { 400 { .compatible = "gw,gsc-adc", }, 401 {} 402 }; 403 404 static struct platform_driver gsc_hwmon_driver = { 405 .driver = { 406 .name = "gsc-hwmon", 407 .of_match_table = gsc_hwmon_of_match, 408 }, 409 .probe = gsc_hwmon_probe, 410 }; 411 412 module_platform_driver(gsc_hwmon_driver); 413 414 MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>"); 415 MODULE_DESCRIPTION("GSC hardware monitor driver"); 416 MODULE_LICENSE("GPL v2"); 417