1Kernel driver it87 2================== 3 4Supported chips: 5 6 * IT8603E/IT8623E 7 8 Prefix: 'it8603' 9 10 Addresses scanned: from Super I/O config space (8 I/O ports) 11 12 Datasheet: Not publicly available 13 14 * IT8620E 15 16 Prefix: 'it8620' 17 18 Addresses scanned: from Super I/O config space (8 I/O ports) 19 20 * IT8628E 21 22 Prefix: 'it8628' 23 24 Addresses scanned: from Super I/O config space (8 I/O ports) 25 26 Datasheet: Not publicly available 27 28 * IT8705F 29 30 Prefix: 'it87' 31 32 Addresses scanned: from Super I/O config space (8 I/O ports) 33 34 Datasheet: Once publicly available at the ITE website, but no longer 35 36 * IT8712F 37 38 Prefix: 'it8712' 39 40 Addresses scanned: from Super I/O config space (8 I/O ports) 41 42 Datasheet: Once publicly available at the ITE website, but no longer 43 44 * IT8716F/IT8726F 45 46 Prefix: 'it8716' 47 48 Addresses scanned: from Super I/O config space (8 I/O ports) 49 50 Datasheet: Once publicly available at the ITE website, but no longer 51 52 * IT8718F 53 54 Prefix: 'it8718' 55 56 Addresses scanned: from Super I/O config space (8 I/O ports) 57 58 Datasheet: Once publicly available at the ITE website, but no longer 59 60 * IT8720F 61 62 Prefix: 'it8720' 63 64 Addresses scanned: from Super I/O config space (8 I/O ports) 65 66 Datasheet: Not publicly available 67 68 * IT8721F/IT8758E 69 70 Prefix: 'it8721' 71 72 Addresses scanned: from Super I/O config space (8 I/O ports) 73 74 Datasheet: Not publicly available 75 76 * IT8728F 77 78 Prefix: 'it8728' 79 80 Addresses scanned: from Super I/O config space (8 I/O ports) 81 82 Datasheet: Not publicly available 83 84 * IT8732F 85 86 Prefix: 'it8732' 87 88 Addresses scanned: from Super I/O config space (8 I/O ports) 89 90 Datasheet: Not publicly available 91 92 * IT8771E 93 94 Prefix: 'it8771' 95 96 Addresses scanned: from Super I/O config space (8 I/O ports) 97 98 Datasheet: Not publicly available 99 100 * IT8772E 101 102 Prefix: 'it8772' 103 104 Addresses scanned: from Super I/O config space (8 I/O ports) 105 106 Datasheet: Not publicly available 107 108 * IT8781F 109 110 Prefix: 'it8781' 111 112 Addresses scanned: from Super I/O config space (8 I/O ports) 113 114 Datasheet: Not publicly available 115 116 * IT8782F 117 118 Prefix: 'it8782' 119 120 Addresses scanned: from Super I/O config space (8 I/O ports) 121 122 Datasheet: Not publicly available 123 124 * IT8783E/F 125 126 Prefix: 'it8783' 127 128 Addresses scanned: from Super I/O config space (8 I/O ports) 129 130 Datasheet: Not publicly available 131 132 * IT8786E 133 134 Prefix: 'it8786' 135 136 Addresses scanned: from Super I/O config space (8 I/O ports) 137 138 Datasheet: Not publicly available 139 140 * IT8790E 141 142 Prefix: 'it8790' 143 144 Addresses scanned: from Super I/O config space (8 I/O ports) 145 146 Datasheet: Not publicly available 147 148 * IT8792E/IT8795E 149 150 Prefix: 'it8792' 151 152 Addresses scanned: from Super I/O config space (8 I/O ports) 153 154 Datasheet: Not publicly available 155 156 * IT87952E 157 158 Prefix: 'it87952' 159 160 Addresses scanned: from Super I/O config space (8 I/O ports) 161 162 Datasheet: Not publicly available 163 164 * SiS950 [clone of IT8705F] 165 166 Prefix: 'it87' 167 168 Addresses scanned: from Super I/O config space (8 I/O ports) 169 170 Datasheet: No longer be available 171 172 173Authors: 174 - Christophe Gauthron 175 - Jean Delvare <jdelvare@suse.de> 176 177 178Module Parameters 179----------------- 180 181* update_vbat bool 182 0 if vbat should report power on value, 1 if vbat should be updated after 183 each read. Default is 0. On some boards the battery voltage is provided 184 by either the battery or the onboard power supply. Only the first reading 185 at power on will be the actual battery voltage (which the chip does 186 automatically). On other boards the battery voltage is always fed to 187 the chip so can be read at any time. Excessive reading may decrease 188 battery life but no information is given in the datasheet. 189 190* fix_pwm_polarity bool 191 Force PWM polarity to active high (DANGEROUS). Some chips are 192 misconfigured by BIOS - PWM values would be inverted. This option tries 193 to fix this. Please contact your BIOS manufacturer and ask him for fix. 194 195* force_id short, short 196 197 Force multiple chip ID to specified value, separated by ','. 198 For example "force_id=0x8689,0x8633". A value of 0 is ignored 199 for that chip. 200 Note: A single force_id value (e.g. "force_id=0x8689") is used for 201 all chips, to only set the first chip use "force_id=0x8689,0". 202 Should only be used for testing. 203 204* ignore_resource_conflict bool 205 206 Similar to acpi_enforce_resources=lax, but only affects this driver. 207 ACPI resource conflicts are ignored if this parameter is provided and 208 set to 1. 209 Provided since there are reports that system-wide acpi_enfore_resources=lax 210 can result in boot failures on some systems. 211 Note: This is inherently risky since it means that both ACPI and this driver 212 may access the chip at the same time. This can result in race conditions and, 213 worst case, result in unexpected system reboots. 214 215 216Hardware Interfaces 217------------------- 218 219All the chips supported by this driver are LPC Super-I/O chips, accessed 220through the LPC bus (ISA-like I/O ports). The IT8712F additionally has an 221SMBus interface to the hardware monitoring functions. This driver no 222longer supports this interface though, as it is slower and less reliable 223than the ISA access, and was only available on a small number of 224motherboard models. 225 226 227Description 228----------- 229 230This driver implements support for the IT8603E, IT8620E, IT8623E, IT8628E, 231IT8705F, IT8712F, IT8716F, IT8718F, IT8720F, IT8721F, IT8726F, IT8728F, IT8732F, 232IT8758E, IT8771E, IT8772E, IT8781F, IT8782F, IT8783E/F, IT8786E, IT8790E, 233IT8792E/IT8795E, IT87952E and SiS950 chips. 234 235These chips are 'Super I/O chips', supporting floppy disks, infrared ports, 236joysticks and other miscellaneous stuff. For hardware monitoring, they 237include an 'environment controller' with 3 temperature sensors, 3 fan 238rotation speed sensors, 8 voltage sensors, associated alarms, and chassis 239intrusion detection. 240 241The IT8712F and IT8716F additionally feature VID inputs, used to report 242the Vcore voltage of the processor. The early IT8712F have 5 VID pins, 243the IT8716F and late IT8712F have 6. They are shared with other functions 244though, so the functionality may not be available on a given system. 245 246The IT8718F and IT8720F also features VID inputs (up to 8 pins) but the value 247is stored in the Super-I/O configuration space. Due to technical limitations, 248this value can currently only be read once at initialization time, so 249the driver won't notice and report changes in the VID value. The two 250upper VID bits share their pins with voltage inputs (in5 and in6) so you 251can't have both on a given board. 252 253The IT8716F, IT8718F, IT8720F, IT8721F/IT8758E and later IT8712F revisions 254have support for 2 additional fans. The additional fans are supported by the 255driver. 256 257The IT8716F, IT8718F, IT8720F, IT8721F/IT8758E, IT8732F, IT8781F, IT8782F, 258IT8783E/F, and late IT8712F and IT8705F also have optional 16-bit tachometer 259counters for fans 1 to 3. This is better (no more fan clock divider mess) but 260not compatible with the older chips and revisions. The 16-bit tachometer mode 261is enabled by the driver when one of the above chips is detected. 262 263The IT8726F is just bit enhanced IT8716F with additional hardware 264for AMD power sequencing. Therefore the chip will appear as IT8716F 265to userspace applications. 266 267The IT8728F, IT8771E, and IT8772E are considered compatible with the IT8721F, 268until a datasheet becomes available (hopefully.) 269 270The IT8603E/IT8623E is a custom design, hardware monitoring part is similar to 271IT8728F. It only supports 3 fans, 16-bit fan mode, and the full speed mode 272of the fan is not supported (value 0 of pwmX_enable). 273 274The IT8620E and IT8628E are custom designs, hardware monitoring part is similar 275to IT8728F. It only supports 16-bit fan mode. Both chips support up to 6 fans. 276 277The IT8790E, IT8792E/IT8795E and IT87952E support up to 3 fans. 16-bit fan 278mode is always enabled. 279 280The IT8732F supports a closed-loop mode for fan control, but this is not 281currently implemented by the driver. 282 283Temperatures are measured in degrees Celsius. An alarm is triggered once 284when the Overtemperature Shutdown limit is crossed. 285 286Fan rotation speeds are reported in RPM (rotations per minute). An alarm is 287triggered if the rotation speed has dropped below a programmable limit. When 28816-bit tachometer counters aren't used, fan readings can be divided by 289a programmable divider (1, 2, 4 or 8) to give the readings more range or 290accuracy. With a divider of 2, the lowest representable value is around 2912600 RPM. Not all RPM values can accurately be represented, so some rounding 292is done. 293 294Voltage sensors (also known as IN sensors) report their values in volts. An 295alarm is triggered if the voltage has crossed a programmable minimum or 296maximum limit. Note that minimum in this case always means 'closest to 297zero'; this is important for negative voltage measurements. On most chips, all 298voltage inputs can measure voltages between 0 and 4.08 volts, with a resolution 299of 0.016 volt. IT8603E, IT8721F/IT8758E and IT8728F can measure between 0 and 3003.06 volts, with a resolution of 0.012 volt. IT8732F can measure between 0 and 3012.8 volts with a resolution of 0.0109 volt. The battery voltage in8 does not 302have limit registers. 303 304On the IT8603E, IT8620E, IT8628E, IT8721F/IT8758E, IT8732F, IT8781F, IT8782F, 305and IT8783E/F, some voltage inputs are internal and scaled inside the chip: 306* in3 (optional) 307* in7 (optional for IT8781F, IT8782F, and IT8783E/F) 308* in8 (always) 309* in9 (relevant for IT8603E only) 310The driver handles this transparently so user-space doesn't have to care. 311 312The VID lines (IT8712F/IT8716F/IT8718F/IT8720F) encode the core voltage value: 313the voltage level your processor should work with. This is hardcoded by 314the mainboard and/or processor itself. It is a value in volts. 315 316If an alarm triggers, it will remain triggered until the hardware register 317is read at least once. This means that the cause for the alarm may already 318have disappeared! Note that in the current implementation, all hardware 319registers are read whenever any data is read (unless it is less than 1.5 320seconds since the last update). This means that you can easily miss 321once-only alarms. 322 323Out-of-limit readings can also result in beeping, if the chip is properly 324wired and configured. Beeping can be enabled or disabled per sensor type 325(temperatures, voltages and fans.) 326 327The IT87xx only updates its values each 1.5 seconds; reading it more often 328will do no harm, but will return 'old' values. 329 330To change sensor N to a thermistor, 'echo 4 > tempN_type' where N is 1, 2, 331or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'. 332Give 0 for unused sensor. Any other value is invalid. To configure this at 333startup, consult lm_sensors's /etc/sensors.conf. (4 = thermistor; 3343 = thermal diode) 335 336 337Fan speed control 338----------------- 339 340The fan speed control features are limited to manual PWM mode. Automatic 341"Smart Guardian" mode control handling is only implemented for older chips 342(see below.) However if you want to go for "manual mode" just write 1 to 343pwmN_enable. 344 345If you are only able to control the fan speed with very small PWM values, 346try lowering the PWM base frequency (pwm1_freq). Depending on the fan, 347it may give you a somewhat greater control range. The same frequency is 348used to drive all fan outputs, which is why pwm2_freq and pwm3_freq are 349read-only. 350 351 352Automatic fan speed control (old interface) 353------------------------------------------- 354 355The driver supports the old interface to automatic fan speed control 356which is implemented by IT8705F chips up to revision F and IT8712F 357chips up to revision G. 358 359This interface implements 4 temperature vs. PWM output trip points. 360The PWM output of trip point 4 is always the maximum value (fan running 361at full speed) while the PWM output of the other 3 trip points can be 362freely chosen. The temperature of all 4 trip points can be freely chosen. 363Additionally, trip point 1 has an hysteresis temperature attached, to 364prevent fast switching between fan on and off. 365 366The chip automatically computes the PWM output value based on the input 367temperature, based on this simple rule: if the temperature value is 368between trip point N and trip point N+1 then the PWM output value is 369the one of trip point N. The automatic control mode is less flexible 370than the manual control mode, but it reacts faster, is more robust and 371doesn't use CPU cycles. 372 373Trip points must be set properly before switching to automatic fan speed 374control mode. The driver will perform basic integrity checks before 375actually switching to automatic control mode. 376 377 378Temperature offset attributes 379----------------------------- 380 381The driver supports temp[1-3]_offset sysfs attributes to adjust the reported 382temperature for thermal diodes or diode-connected thermal transistors. 383If a temperature sensor is configured for thermistors, the attribute values 384are ignored. If the thermal sensor type is Intel PECI, the temperature offset 385must be programmed to the critical CPU temperature. 386