On 6/2/2021 4:05 AM, Pavel Machek wrote:
Hi!
[ok] [locate] failed rebuild pfa hotspare ica ifa invalid disabled
So what does this do? Turns the LED on if driver is in "ok" or
"locate" states?
This would cause the system to somehow show the user that that this drive
(or drive slot) is the one that it wants a person to be able to physically
locate (possibly by flashing a blue LED on/near the drive), and also that
the drive is OK. It would presumably do that by lighting the LEDs on/near
the drive with certain colors and/or flashing patterns, though it could, in
theory, put "OK" in an LCD on the drive slot. How the states are displayed
to the user is beyond the scope of the specs.
(The _DSM and NPEM specs provide for a way to control status LEDs on a drive
or drive slot. Typically drives will have 2 or 3 LEDs that are illuminated
in different colors or flashing patterns to indicate various states (like
those listed in IBPI / SFF-8489), though the _DSM / NPEM specs do not
specify how the states are displayed.)
Well, LED subsystem expects to know how many LEDs are there and what
the LEDs are, and expects individual control over them.
"2 or 3 LEDs with unknown patterns", or LCD display is outside of scope
of LED subsystem, so this should be independend.
Best regards,
Pavel
Yes... I had originally submitted this without using the LED subsystem,
and Greg K-H said I had to (see
https://www.spinics.net/lists/linux-pci/msg102013.html). Here's the
relevant bit.
(Greg K-H:)
> And why isn't this code using the existing LED subsystem? Don't create
> random new driver-specific sysfs files that do things the existing class
> drivers do please.
>
(Me:)
I did consider the LED subsystem, but I don't think it is a great match.
>> In spite of the name, this _DSM doesn't directly control individual
LEDs--it
sets the state(s) of the PCI port to which an SSD may be connected, so that
it may be conveyed to the user... a processor (or at least some logic) will
decide how to show which states are active, probably by setting combinations
of LEDs to certain colors or blink patterns, or possibly on some other type
of display.
(Greg K-H:)
If you are allowing LEDs to be controlled by the user, then yes, you
have to use the LED subsystem as you should never try to create a brand
new driver-specific user/kernel API just for your tiny driver right?
Please work with the subsystems we have, they are unified for a reason.
So I'm not sure what to do.
