clk: composite: Also consider .determine_rate for rate + mux composites
Commit 69a00fb3 ("clk: divider: Implement and wire up .determine_rate by default") switches clk_divider_ops to implement .determine_rate by default. This breaks composite clocks with multiple parents because clk-composite.c does not use the special handling for mux + divider combinations anymore (that was restricted to rate clocks which only implement .round_rate, but not .determine_rate). Alex reports: This breaks lot of clocks for Rockchip which intensively uses composites, i.e. those clocks will always stay at the initial parent, which in some cases is the XTAL clock and I strongly guess it is the same for other platforms, which use composite clocks having more than one parent (e.g. mediatek, ti ...) Example (RK3399) clk_sdio is set (initialized) with XTAL (24 MHz) as parent in u-boot. It will always stay at this parent, even if the mmc driver sets a rate of 200 MHz (fails, as the nature of things), which should switch it to any of its possible parent PLLs defined in mux_pll_src_cpll_gpll_npll_ppll_upll_24m_p (see clk-rk3399.c) - which never happens. Restore the original behavior by changing the priority of the conditions inside clk-composite.c. Now the special rate + mux case (with rate_ops having a .round_rate - which is still the case for the default clk_divider_ops) is preferred over rate_ops which have .determine_rate defined (and not further considering the mux). Fixes: 69a00fb3 ("clk: divider: Implement and wire up .determine_rate by default") Reported-by: Alex Bee <knaerzche@gmail.com> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Link: https://lore.kernel.org/r/20211016105022.303413-2-martin.blumenstingl@googlemail.com Tested-by: Alex Bee <knaerzche@gmail.com> Tested-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
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