| Kernel driver max6650 |
| ===================== |
| |
| Supported chips: |
| * Maxim MAX6650 |
| Prefix: 'max6650' |
| Addresses scanned: none |
| Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf |
| * Maxim MAX6651 |
| Prefix: 'max6651' |
| Addresses scanned: none |
| Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf |
| |
| Authors: |
| Hans J. Koch <hjk@hansjkoch.de> |
| John Morris <john.morris@spirentcom.com> |
| Claus Gindhart <claus.gindhart@kontron.com> |
| |
| Description |
| ----------- |
| |
| This driver implements support for the Maxim MAX6650 and MAX6651. |
| |
| The 2 devices are very similar, but the MAX6550 has a reduced feature |
| set, e.g. only one fan-input, instead of 4 for the MAX6651. |
| |
| The driver is not able to distinguish between the 2 devices. |
| |
| The driver provides the following sensor accesses in sysfs: |
| |
| fan1_input ro fan tachometer speed in RPM |
| fan2_input ro " |
| fan3_input ro " |
| fan4_input ro " |
| fan1_target rw desired fan speed in RPM (closed loop mode only) |
| pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop |
| pwm1 rw relative speed (0-255), 255=max. speed. |
| Used in open loop mode only. |
| fan1_div rw sets the speed range the inputs can handle. Legal |
| values are 1, 2, 4, and 8. Use lower values for |
| faster fans. |
| |
| Usage notes |
| ----------- |
| |
| This driver does not auto-detect devices. You will have to instantiate the |
| devices explicitly. Please see Documentation/i2c/instantiating-devices for |
| details. |
| |
| Module parameters |
| ----------------- |
| |
| If your board has a BIOS that initializes the MAX6650/6651 correctly, you can |
| simply load your module without parameters. It won't touch the configuration |
| registers then. If your board BIOS doesn't initialize the chip, or you want |
| different settings, you can set the following parameters: |
| |
| voltage_12V: 5=5V fan, 12=12V fan, 0=don't change |
| prescaler: Possible values are 1,2,4,8,16, or 0 for don't change |
| clock: The clock frequency in Hz of the chip the driver should assume [254000] |
| |
| Please have a look at the MAX6650/6651 data sheet and make sure that you fully |
| understand the meaning of these parameters before you attempt to change them. |
| |
