2020. december 28., hétfő 23:02 keltezéssel, Roderick Colenbrander írta:

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quoted

Furthermore, I don't quite see the purpose of this function. The LED core
can handle if no brightness_get() callback is provided. And since this
function returns just a cached value, I fail to see how it is different from
the default behaviour of the LED core, which is returning the last brightness
value. Am I missing something?

Not all values may get set through sysfs. For example in the next
patch (12/13) the driver sets a default player LED mask value directly
and may set e.g. 0x1f or so. This could use the LED APIs, but the LED
framework doesn't have any group LED support (besides the new
multicolor class) and as such would get scheduled across multiple
output reports.
[...]

You're right, I've missed that.