pinctrl in phosphor-hwmon

[Matt Spinler]

On 12/11/2019 12:40 AM, Deng Tyler wrote:
> I added gpio control in my fan driver but I still met some problem. 
> While phosphor-hwmon reading fan0_input, the fan tach driver change 2 
> gpio pin and sleep 2 seconds to return rpm value for stable. There are 
> 12 fan sensors in my platform so the phosphor-hwmon need wait 24 
> senconds at least to get rpm. The waiting time cause dbus hang while 
> issuing ipmi sensor command. Do you have any suggestions?

I vaguely remember someone else had this problem before, and it turned 
out to be a device driver
problem as the reason it was so slow.

Otherwise, the reads could probably be changed to be asynchronous, but 
that could be a pretty big
change to the application.

>
> Tyler
>
> Matt Spinler <mspinler at linux.ibm.com <mailto:mspinler at linux.ibm.com>> 
> 於 2019年12月11日 週三 上午12:29寫道：
>
>
>
>     On 12/9/2019 11:08 PM, Deng Tyler wrote:
>     > Hi Matt:
>     >     Thank for your response that's really helpful. I check the link
>     > and it seems allow a gpio set to high before/after reading a
>     > correspond sensor. Is it possible change 2 gpio to high/low for
>     > reading a correspond sensor?
>
>     That isn't possible in the current code, but I don't see why someone
>     couldn't add that feature.
>
>     >
>     > Regards,
>     > Tyler
>     >
>     > Matt Spinler <mspinler at linux.ibm.com
>     <mailto:mspinler at linux.ibm.com> <mailto:mspinler at linux.ibm.com
>     <mailto:mspinler at linux.ibm.com>>>
>     > 於 2019年12月9日 週一 下午10:58寫道：
>     >
>     >
>     >
>     >     On 12/9/2019 6:15 AM, Deng Tyler wrote:
>     >     > Hi all:
>     >     >     Does phosphor-hwmon support changing gpio pin before read
>     >     > /sys/class/hwmon/hwmon0/fan*_input while monitoring fan
>     sensor?
>     >     In my
>     >     > platform, fans gpio are connect to pin-mux and I need
>     control gpio
>     >     > before get fan tach rpm.
>     >
>     >     It does have the ability to modify a GPIO before/after a
>     reading:
>     >
>     https://github.com/openbmc/phosphor-hwmon/blob/master/mainloop.cpp#L447
>     >
>     >     configured by some lines in the conf file, like:
>     >
>     https://github.com/openbmc/meta-ibm/blob/master/meta-romulus/recipes-phosphor/sensors/phosphor-hwmon/obmc/hwmon/iio-hwmon-battery.conf#L4
>     >
>     >     >
>     >     > Regards,
>     >     > Tyler
>     >
>