|Kernel driver g760a
| * Global Mixed-mode Technology Inc. G760A
| Prefix: 'g760a'
| Datasheet: Publicly available at the GMT website
|Author: Herbert Valerio Riedel <firstname.lastname@example.org>
|The GMT G760A Fan Speed PWM Controller is connected directly to a fan
|and performs closed-loop control of the fan speed.
|The fan speed is programmed by setting the period via 'pwm1' of two
|consecutive speed pulses. The period is defined in terms of clock
|cycle counts of an assumed 32kHz clock source.
|Setting a period of 0 stops the fan; setting the period to 255 sets
|fan to maximum speed.
|The measured fan rotation speed returned via 'fan1_input' is derived
|from the measured speed pulse period by assuming again a 32kHz clock
|source and a 2 pulse-per-revolution fan.
|The 'alarms' file provides access to the two alarm bits provided by
|the G760A chip's status register: Bit 0 is set when the actual fan
|speed differs more than 20% with respect to the programmed fan speed;
|bit 1 is set when fan speed is below 1920 RPM.
|The g760a driver will not update its values more frequently than every
|other second; reading them more often will do no harm, but will return