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 21 #define GSC_HWMON_RESOLUTION 12 22 #define GSC_HWMON_VREF 2500 23 24 struct gsc_hwmon_data { 25 struct gsc_dev *gsc; 26 struct gsc_hwmon_platform_data *pdata; 27 struct regmap *regmap; 28 const struct gsc_hwmon_channel *temp_ch[GSC_HWMON_MAX_TEMP_CH]; 29 const struct gsc_hwmon_channel *in_ch[GSC_HWMON_MAX_IN_CH]; 30 u32 temp_config[GSC_HWMON_MAX_TEMP_CH + 1]; 31 u32 in_config[GSC_HWMON_MAX_IN_CH + 1]; 32 struct hwmon_channel_info temp_info; 33 struct hwmon_channel_info in_info; 34 const struct hwmon_channel_info *info[3]; 35 struct hwmon_chip_info chip; 36 }; 37 38 static struct regmap_bus gsc_hwmon_regmap_bus = { 39 .reg_read = gsc_read, 40 .reg_write = gsc_write, 41 }; 42 43 static const struct regmap_config gsc_hwmon_regmap_config = { 44 .reg_bits = 8, 45 .val_bits = 8, 46 .cache_type = REGCACHE_NONE, 47 }; 48 49 static ssize_t pwm_auto_point_temp_show(struct device *dev, 50 struct device_attribute *devattr, 51 char *buf) 52 { 53 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 54 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 55 u8 reg = hwmon->pdata->fan_base + (2 * attr->index); 56 u8 regs[2]; 57 int ret; 58 59 ret = regmap_bulk_read(hwmon->regmap, reg, regs, 2); 60 if (ret) 61 return ret; 62 63 ret = regs[0] | regs[1] << 8; 64 return sprintf(buf, "%d\n", ret * 10); 65 } 66 67 static ssize_t pwm_auto_point_temp_store(struct device *dev, 68 struct device_attribute *devattr, 69 const char *buf, size_t count) 70 { 71 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 72 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 73 u8 reg = hwmon->pdata->fan_base + (2 * attr->index); 74 u8 regs[2]; 75 long temp; 76 int err; 77 78 if (kstrtol(buf, 10, &temp)) 79 return -EINVAL; 80 81 temp = clamp_val(temp, 0, 10000); 82 temp = DIV_ROUND_CLOSEST(temp, 10); 83 84 regs[0] = temp & 0xff; 85 regs[1] = (temp >> 8) & 0xff; 86 err = regmap_bulk_write(hwmon->regmap, reg, regs, 2); 87 if (err) 88 return err; 89 90 return count; 91 } 92 93 static ssize_t pwm_auto_point_pwm_show(struct device *dev, 94 struct device_attribute *devattr, 95 char *buf) 96 { 97 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 98 99 return sprintf(buf, "%d\n", 255 * (50 + (attr->index * 10)) / 100); 100 } 101 102 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm_auto_point_pwm, 0); 103 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, pwm_auto_point_temp, 0); 104 105 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point2_pwm, pwm_auto_point_pwm, 1); 106 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, pwm_auto_point_temp, 1); 107 108 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm_auto_point_pwm, 2); 109 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, pwm_auto_point_temp, 2); 110 111 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point4_pwm, pwm_auto_point_pwm, 3); 112 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, pwm_auto_point_temp, 3); 113 114 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm_auto_point_pwm, 4); 115 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point5_temp, pwm_auto_point_temp, 4); 116 117 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point6_pwm, pwm_auto_point_pwm, 5); 118 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point6_temp, pwm_auto_point_temp, 5); 119 120 static struct attribute *gsc_hwmon_attributes[] = { 121 &sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr, 122 &sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr, 123 &sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr, 124 &sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr, 125 &sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr, 126 &sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr, 127 &sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr, 128 &sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr, 129 &sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr, 130 &sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr, 131 &sensor_dev_attr_pwm1_auto_point6_pwm.dev_attr.attr, 132 &sensor_dev_attr_pwm1_auto_point6_temp.dev_attr.attr, 133 NULL 134 }; 135 136 static const struct attribute_group gsc_hwmon_group = { 137 .attrs = gsc_hwmon_attributes, 138 }; 139 __ATTRIBUTE_GROUPS(gsc_hwmon); 140 141 static int 142 gsc_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, 143 int channel, long *val) 144 { 145 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 146 const struct gsc_hwmon_channel *ch; 147 int sz, ret; 148 long tmp; 149 u8 buf[3]; 150 151 switch (type) { 152 case hwmon_in: 153 ch = hwmon->in_ch[channel]; 154 break; 155 case hwmon_temp: 156 ch = hwmon->temp_ch[channel]; 157 break; 158 default: 159 return -EOPNOTSUPP; 160 } 161 162 sz = (ch->mode == mode_voltage) ? 3 : 2; 163 ret = regmap_bulk_read(hwmon->regmap, ch->reg, buf, sz); 164 if (ret) 165 return ret; 166 167 tmp = 0; 168 while (sz-- > 0) 169 tmp |= (buf[sz] << (8 * sz)); 170 171 switch (ch->mode) { 172 case mode_temperature: 173 if (tmp > 0x8000) 174 tmp -= 0xffff; 175 break; 176 case mode_voltage_raw: 177 tmp = clamp_val(tmp, 0, BIT(GSC_HWMON_RESOLUTION)); 178 /* scale based on ref voltage and ADC resolution */ 179 tmp *= GSC_HWMON_VREF; 180 tmp >>= GSC_HWMON_RESOLUTION; 181 /* scale based on optional voltage divider */ 182 if (ch->vdiv[0] && ch->vdiv[1]) { 183 tmp *= (ch->vdiv[0] + ch->vdiv[1]); 184 tmp /= ch->vdiv[1]; 185 } 186 /* adjust by uV offset */ 187 tmp += ch->mvoffset; 188 break; 189 case mode_voltage: 190 /* no adjustment needed */ 191 break; 192 } 193 194 *val = tmp; 195 196 return 0; 197 } 198 199 static int 200 gsc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type, 201 u32 attr, int channel, const char **buf) 202 { 203 struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev); 204 205 switch (type) { 206 case hwmon_in: 207 *buf = hwmon->in_ch[channel]->name; 208 break; 209 case hwmon_temp: 210 *buf = hwmon->temp_ch[channel]->name; 211 break; 212 default: 213 return -ENOTSUPP; 214 } 215 216 return 0; 217 } 218 219 static umode_t 220 gsc_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr, 221 int ch) 222 { 223 return 0444; 224 } 225 226 static const struct hwmon_ops gsc_hwmon_ops = { 227 .is_visible = gsc_hwmon_is_visible, 228 .read = gsc_hwmon_read, 229 .read_string = gsc_hwmon_read_string, 230 }; 231 232 static struct gsc_hwmon_platform_data * 233 gsc_hwmon_get_devtree_pdata(struct device *dev) 234 { 235 struct gsc_hwmon_platform_data *pdata; 236 struct gsc_hwmon_channel *ch; 237 struct fwnode_handle *child; 238 struct device_node *fan; 239 int nchannels; 240 241 nchannels = device_get_child_node_count(dev); 242 if (nchannels == 0) 243 return ERR_PTR(-ENODEV); 244 245 pdata = devm_kzalloc(dev, 246 sizeof(*pdata) + nchannels * sizeof(*ch), 247 GFP_KERNEL); 248 if (!pdata) 249 return ERR_PTR(-ENOMEM); 250 ch = (struct gsc_hwmon_channel *)(pdata + 1); 251 pdata->channels = ch; 252 pdata->nchannels = nchannels; 253 254 /* fan controller base address */ 255 fan = of_find_compatible_node(dev->parent->of_node, NULL, "gw,gsc-fan"); 256 if (fan && of_property_read_u32(fan, "reg", &pdata->fan_base)) { 257 dev_err(dev, "fan node without base\n"); 258 return ERR_PTR(-EINVAL); 259 } 260 261 /* allocate structures for channels and count instances of each type */ 262 device_for_each_child_node(dev, child) { 263 if (fwnode_property_read_string(child, "label", &ch->name)) { 264 dev_err(dev, "channel without label\n"); 265 fwnode_handle_put(child); 266 return ERR_PTR(-EINVAL); 267 } 268 if (fwnode_property_read_u32(child, "reg", &ch->reg)) { 269 dev_err(dev, "channel without reg\n"); 270 fwnode_handle_put(child); 271 return ERR_PTR(-EINVAL); 272 } 273 if (fwnode_property_read_u32(child, "gw,mode", &ch->mode)) { 274 dev_err(dev, "channel without mode\n"); 275 fwnode_handle_put(child); 276 return ERR_PTR(-EINVAL); 277 } 278 if (ch->mode > mode_max) { 279 dev_err(dev, "invalid channel mode\n"); 280 fwnode_handle_put(child); 281 return ERR_PTR(-EINVAL); 282 } 283 284 if (!fwnode_property_read_u32(child, 285 "gw,voltage-offset-microvolt", 286 &ch->mvoffset)) 287 ch->mvoffset /= 1000; 288 fwnode_property_read_u32_array(child, 289 "gw,voltage-divider-ohms", 290 ch->vdiv, ARRAY_SIZE(ch->vdiv)); 291 ch++; 292 } 293 294 return pdata; 295 } 296 297 static int gsc_hwmon_probe(struct platform_device *pdev) 298 { 299 struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent); 300 struct device *dev = &pdev->dev; 301 struct device *hwmon_dev; 302 struct gsc_hwmon_platform_data *pdata = dev_get_platdata(dev); 303 struct gsc_hwmon_data *hwmon; 304 const struct attribute_group **groups; 305 int i, i_in, i_temp; 306 307 if (!pdata) { 308 pdata = gsc_hwmon_get_devtree_pdata(dev); 309 if (IS_ERR(pdata)) 310 return PTR_ERR(pdata); 311 } 312 313 hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL); 314 if (!hwmon) 315 return -ENOMEM; 316 hwmon->gsc = gsc; 317 hwmon->pdata = pdata; 318 319 hwmon->regmap = devm_regmap_init(dev, &gsc_hwmon_regmap_bus, 320 gsc->i2c_hwmon, 321 &gsc_hwmon_regmap_config); 322 if (IS_ERR(hwmon->regmap)) 323 return PTR_ERR(hwmon->regmap); 324 325 for (i = 0, i_in = 0, i_temp = 0; i < hwmon->pdata->nchannels; i++) { 326 const struct gsc_hwmon_channel *ch = &pdata->channels[i]; 327 328 switch (ch->mode) { 329 case mode_temperature: 330 if (i_temp == GSC_HWMON_MAX_TEMP_CH) { 331 dev_err(gsc->dev, "too many temp channels\n"); 332 return -EINVAL; 333 } 334 hwmon->temp_ch[i_temp] = ch; 335 hwmon->temp_config[i_temp] = HWMON_T_INPUT | 336 HWMON_T_LABEL; 337 i_temp++; 338 break; 339 case mode_voltage: 340 case mode_voltage_raw: 341 if (i_in == GSC_HWMON_MAX_IN_CH) { 342 dev_err(gsc->dev, "too many input channels\n"); 343 return -EINVAL; 344 } 345 hwmon->in_ch[i_in] = ch; 346 hwmon->in_config[i_in] = 347 HWMON_I_INPUT | HWMON_I_LABEL; 348 i_in++; 349 break; 350 default: 351 dev_err(gsc->dev, "invalid mode: %d\n", ch->mode); 352 return -EINVAL; 353 } 354 } 355 356 /* setup config structures */ 357 hwmon->chip.ops = &gsc_hwmon_ops; 358 hwmon->chip.info = hwmon->info; 359 hwmon->info[0] = &hwmon->temp_info; 360 hwmon->info[1] = &hwmon->in_info; 361 hwmon->temp_info.type = hwmon_temp; 362 hwmon->temp_info.config = hwmon->temp_config; 363 hwmon->in_info.type = hwmon_in; 364 hwmon->in_info.config = hwmon->in_config; 365 366 groups = pdata->fan_base ? gsc_hwmon_groups : NULL; 367 hwmon_dev = devm_hwmon_device_register_with_info(dev, 368 KBUILD_MODNAME, hwmon, 369 &hwmon->chip, groups); 370 return PTR_ERR_OR_ZERO(hwmon_dev); 371 } 372 373 static const struct of_device_id gsc_hwmon_of_match[] = { 374 { .compatible = "gw,gsc-adc", }, 375 {} 376 }; 377 378 static struct platform_driver gsc_hwmon_driver = { 379 .driver = { 380 .name = "gsc-hwmon", 381 .of_match_table = gsc_hwmon_of_match, 382 }, 383 .probe = gsc_hwmon_probe, 384 }; 385 386 module_platform_driver(gsc_hwmon_driver); 387 388 MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>"); 389 MODULE_DESCRIPTION("GSC hardware monitor driver"); 390 MODULE_LICENSE("GPL v2"); 391