| Kernel driver amc6821 | |
| ===================== | |
| Supported chips: | |
| Texas Instruments AMC6821 | |
| Prefix: 'amc6821' | |
| Addresses scanned: 0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e, 0x4c, 0x4d, 0x4e | |
| Datasheet: http://focus.ti.com/docs/prod/folders/print/amc6821.html | |
| Authors: | |
| Tomaz Mertelj <tomaz.mertelj@guest.arnes.si> | |
| Description | |
| ----------- | |
| This driver implements support for the Texas Instruments amc6821 chip. | |
| The chip has one on-chip and one remote temperature sensor and one pwm fan | |
| regulator. | |
| The pwm can be controlled either from software or automatically. | |
| The driver provides the following sensor accesses in sysfs: | |
| temp1_input ro on-chip temperature | |
| temp1_min rw " | |
| temp1_max rw " | |
| temp1_crit rw " | |
| temp1_min_alarm ro " | |
| temp1_max_alarm ro " | |
| temp1_crit_alarm ro " | |
| temp2_input ro remote temperature | |
| temp2_min rw " | |
| temp2_max rw " | |
| temp2_crit rw " | |
| temp2_min_alarm ro " | |
| temp2_max_alarm ro " | |
| temp2_crit_alarm ro " | |
| temp2_fault ro " | |
| fan1_input ro tachometer speed | |
| fan1_min rw " | |
| fan1_max rw " | |
| fan1_fault ro " | |
| fan1_div rw Fan divisor can be either 2 or 4. | |
| pwm1 rw pwm1 | |
| pwm1_enable rw regulator mode, 1=open loop, 2=fan controlled | |
| by remote temperature, 3=fan controlled by | |
| combination of the on-chip temperature and | |
| remote-sensor temperature, | |
| pwm1_auto_channels_temp ro 1 if pwm_enable==2, 3 if pwm_enable==3 | |
| pwm1_auto_point1_pwm ro Hardwired to 0, shared for both | |
| temperature channels. | |
| pwm1_auto_point2_pwm rw This value is shared for both temperature | |
| channels. | |
| pwm1_auto_point3_pwm rw Hardwired to 255, shared for both | |
| temperature channels. | |
| temp1_auto_point1_temp ro Hardwired to temp2_auto_point1_temp | |
| which is rw. Below this temperature fan stops. | |
| temp1_auto_point2_temp rw The low-temperature limit of the proportional | |
| range. Below this temperature | |
| pwm1 = pwm1_auto_point2_pwm. It can go from | |
| 0 degree C to 124 degree C in steps of | |
| 4 degree C. Read it out after writing to get | |
| the actual value. | |
| temp1_auto_point3_temp rw Above this temperature fan runs at maximum | |
| speed. It can go from temp1_auto_point2_temp. | |
| It can only have certain discrete values | |
| which depend on temp1_auto_point2_temp and | |
| pwm1_auto_point2_pwm. Read it out after | |
| writing to get the actual value. | |
| temp2_auto_point1_temp rw Must be between 0 degree C and 63 degree C and | |
| it defines the passive cooling temperature. | |
| Below this temperature the fan stops in | |
| the closed loop mode. | |
| temp2_auto_point2_temp rw The low-temperature limit of the proportional | |
| range. Below this temperature | |
| pwm1 = pwm1_auto_point2_pwm. It can go from | |
| 0 degree C to 124 degree C in steps | |
| of 4 degree C. | |
| temp2_auto_point3_temp rw Above this temperature fan runs at maximum | |
| speed. It can only have certain discrete | |
| values which depend on temp2_auto_point2_temp | |
| and pwm1_auto_point2_pwm. Read it out after | |
| writing to get actual value. | |
| Module parameters | |
| ----------------- | |
| If your board has a BIOS that initializes the amc6821 correctly, you should | |
| load the module with: init=0. | |
| If your board BIOS doesn't initialize the chip, or you want | |
| different settings, you can set the following parameters: | |
| init=1, | |
| pwminv: 0 default pwm output, 1 inverts pwm output. | |