clk: qcom: gdsc: propagate gdsc_enable() failure for ALWAYS_ON domains

GENPD_FLAG_ALWAYS_ON requires the underlying domain to be on at
genpd_init() time -- the framework will refuse to register the domain
otherwise. When the cold readback in gdsc_init() finds an ALWAYS_ON
GDSC powered down, the driver tries to bring it back up:

	} else if (sc->flags & ALWAYS_ON) {
		/* If ALWAYS_ON GDSCs are not ON, turn them ON */
		gdsc_enable(&sc->pd);
		on = true;
	}

but discards the return value: if gdsc_enable() fails (regmap write
error, the long-form sequence's status poll times out, or the
HW_CTRL hand-off errors) the code still sets on=true and falls
through to pm_genpd_init(..., !on) -- which then registers the
domain in the ON state and sets GENPD_FLAG_ALWAYS_ON, even though
the silicon is actually off. Subsequent consumer probes will see
genpd report "on" while accessing dead registers and hang or read
garbage.

Catch the failure and surface it: returning the error from
gdsc_init() makes the provider probe fail with the underlying errno,
which propagates to consumers as -EPROBE_DEFER (or fatal if the
hardware really is broken) rather than silently lying about the
rail state.

Signed-off-by: Herman van Hazendonk <github.com@herrie.org>
Fixes: fb55bea1fe ("clk: qcom: gdsc: Add support for ALWAYS_ON gdscs")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260602140934.796697-3-github.com@herrie.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
This commit is contained in:
Herman van Hazendonk 2026-06-02 16:09:33 +02:00 • committed by Bjorn Andersson
commit eea55fc694