X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Fhwmon%2Fw83627ehf;h=030fac6cec7a21b047780120bef166ff5975734a;hb=e30fab3ad34aa8bfb55c9f0337d4a92a0595f41f;hp=fae3b781d82d48f6f91a5b261601499ee450e127;hpb=82965addad66fce61a92c5f03104ea90b0b87124;p=linux-2.6-omap-h63xx.git diff --git a/Documentation/hwmon/w83627ehf b/Documentation/hwmon/w83627ehf index fae3b781d82..030fac6cec7 100644 --- a/Documentation/hwmon/w83627ehf +++ b/Documentation/hwmon/w83627ehf @@ -2,31 +2,34 @@ Kernel driver w83627ehf ======================= Supported chips: - * Winbond W83627EHF/EHG (ISA access ONLY) + * Winbond W83627EHF/EHG/DHG (ISA access ONLY) Prefix: 'w83627ehf' Addresses scanned: ISA address retrieved from Super I/O registers - Datasheet: http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83627EHF_%20W83627EHGb.pdf + Datasheet: + http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83627EHF_%20W83627EHGb.pdf + DHG datasheet confidential. Authors: Jean Delvare Yuan Mu (Winbond) - Rudolf Marek + Rudolf Marek + David Hubbard Description ----------- -This driver implements support for the Winbond W83627EHF and W83627EHG -super I/O chips. We will refer to them collectively as Winbond chips. +This driver implements support for the Winbond W83627EHF, W83627EHG, and +W83627DHG super I/O chips. We will refer to them collectively as Winbond chips. The chips implement three temperature sensors, five fan rotation -speed sensors, ten analog voltage sensors, alarms with beep warnings (control -unimplemented), and some automatic fan regulation strategies (plus manual -fan control mode). +speed sensors, ten analog voltage sensors (only nine for the 627DHG), alarms +with beep warnings (control unimplemented), and some automatic fan regulation +strategies (plus manual fan control mode). Temperatures are measured in degrees Celsius and measurement resolution is 1 degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when the temperature gets higher than high limit; it stays on until the temperature -falls below the Hysteresis value. +falls below the hysteresis value. Fan rotation speeds are reported in RPM (rotations per minute). An alarm is triggered if the rotation speed has dropped below a programmable limit. Fan @@ -55,6 +58,9 @@ prog -> pwm4 (the programmable setting is not supported by the driver) /sys files ---------- +name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG, + it is set to "w83627ehf" and for the W83627DHG it is set to "w83627dhg" + pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range: 0 (stop) to 255 (full) @@ -67,9 +73,9 @@ Thermal Cruise mode If the temperature is in the range defined by: -pwm[1-4]_target - set target temperature, unit millidegree Celcius +pwm[1-4]_target - set target temperature, unit millidegree Celsius (range 0 - 127000) -pwm[1-4]_tolerance - tolerance, unit millidegree Celcius (range 0 - 15000) +pwm[1-4]_tolerance - tolerance, unit millidegree Celsius (range 0 - 15000) there are no changes to fan speed. Once the temperature leaves the interval, fan speed increases (temp is higher) or decreases if lower than desired. @@ -83,3 +89,37 @@ pwm[1-4]_stop_time - how many milliseconds [ms] must elapse to switch Note: last two functions are influenced by other control bits, not yet exported by the driver, so a change might not have any effect. + +Implementation Details +---------------------- + +Future driver development should bear in mind that the following registers have +different functions on the 627EHF and the 627DHG. Some registers also have +different power-on default values, but BIOS should already be loading +appropriate defaults. Note that bank selection must be performed as is currently +done in the driver for all register addresses. + +0x49: only on DHG, selects temperature source for AUX fan, CPU fan0 +0x4a: not completely documented for the EHF and the DHG documentation assigns + different behavior to bits 7 and 6, including extending the temperature + input selection to SmartFan I, not just SmartFan III. Testing on the EHF + will reveal whether they are compatible or not. + +0x58: Chip ID: 0xa1=EHF 0xc1=DHG +0x5e: only on DHG, has bits to enable "current mode" temperature detection and + critical temperature protection +0x45b: only on EHF, bit 3, vin4 alarm (EHF supports 10 inputs, only 9 on DHG) +0x552: only on EHF, vin4 +0x558: only on EHF, vin4 high limit +0x559: only on EHF, vin4 low limit +0x6b: only on DHG, SYS fan critical temperature +0x6c: only on DHG, CPU fan0 critical temperature +0x6d: only on DHG, AUX fan critical temperature +0x6e: only on DHG, CPU fan1 critical temperature + +0x50-0x55 and 0x650-0x657 are marked "Test Register" for the EHF, but "Reserved + Register" for the DHG + +The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and +the ICH8 southbridge gets that data via PECI from the DHG, so that the +southbridge drives the fans. And the DHG supports SST, a one-wire serial bus.