Re: [PATCH 4/4] clk: Warn if we register a mux without determine_rate

From: AngeloGioacchino Del Regno
Date: Tue Oct 18 2022 - 10:35:18 EST


Il 18/10/22 15:52, Maxime Ripard ha scritto:
The determine_rate hook allows to select the proper parent and its rate
for a given clock configuration. On another hand, set_parent is there to
change the parent of a mux.

Some clocks provide a set_parent hook but don't implement
determine_rate. In such a case, set_parent is pretty much useless since
the clock framework will always assume the current parent is to be used,
and we will thus never change it.

This situation can be solved in two ways:
- either we don't need to change the parent, and we thus shouldn't
implement set_parent;
- or we don't want to change the parent, in this case we should set
CLK_SET_RATE_NO_REPARENT;
- or we're missing a determine_rate implementation.

The latter is probably just an oversight from the driver's author, and
we should thus raise their awareness about the fact that the current
state of the driver is confusing.

It's not clear at this point how many drivers are affected though, so
let's make it a warning instead of an error for now.

Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>

That solves my concerns :-) :-)

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>