| Kernel driver max6650 | 
 | ===================== | 
 |  | 
 | Supported chips: | 
 |   * Maxim 6650 / 6651 | 
 |     Prefix: 'max6650' | 
 |     Addresses scanned: I2C 0x1b, 0x1f, 0x48, 0x4b | 
 |     Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf | 
 |  | 
 | Authors: | 
 |     Hans J. Koch <hjk@linutronix.de> | 
 |     John Morris <john.morris@spirentcom.com> | 
 |     Claus Gindhart <claus.gindhart@kontron.com> | 
 |  | 
 | Description | 
 | ----------- | 
 |  | 
 | This driver implements support for the Maxim 6650/6651 | 
 |  | 
 | The 2 devices are very similar, but the Maxim 6550 has a reduced feature | 
 | set, e.g. only one fan-input, instead of 4 for the 6651. | 
 |  | 
 | 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. | 
 |  | 
 | 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. | 
 |  |