diff mbox series

[RFC,2/3] Documentation: pwm-fan: Add description for RPM support

Message ID 1548860827-29796-3-git-send-email-stefan.wahren@i2se.com (mailing list archive)
State Changes Requested
Headers show
Series hwmon: pwm-fan: Add RPM support | expand

Commit Message

Stefan Wahren Jan. 30, 2019, 3:07 p.m. UTC
This adds a short description for the new RPM support of the pwm-fan
driver.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 Documentation/hwmon/pwm-fan | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/hwmon/pwm-fan b/Documentation/hwmon/pwm-fan
index 18529d2..a1ba34c 100644
--- a/Documentation/hwmon/pwm-fan
+++ b/Documentation/hwmon/pwm-fan
@@ -15,3 +15,7 @@  The driver implements a simple interface for driving a fan connected to
 a PWM output. It uses the generic PWM interface, thus it can be used with
 a range of SoCs. The driver exposes the fan to the user space through
 the hwmon's sysfs interface.
+
+The measured fan rotation speed returned via 'fan1_input' is derived
+from the sampled interrupts from the tachometer signal by assuming
+a 2 pulse-per-revolution fan.