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An invalid >device tree can hand providers a zero modulation frequency or a spread >ratio above 100%, and each provider would have to add the same checks >to protect e.g. divisions in its rate computations. > >Fixes: c86814e70390 ("clk: Introduce clk_hw_set_spread_spectrum") >Signed-off-by: Dario Binacchi >--- > >(no changes since v1) > > drivers/clk/clk.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > >diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c >index fef87167a60b..208caf60eeb5 100644 >--- a/drivers/clk/clk.c >+++ b/drivers/clk/clk.c >@@ -2851,6 +2851,20 @@ int clk_hw_set_spread_spectrum(struct clk_hw *hw, const struct clk_spread_spectr > if (!hw) > return 0; > >+ switch (ss_conf->method) { >+ case CLK_SPREAD_NO: >+ break; >+ case CLK_SPREAD_CENTER: >+ case CLK_SPREAD_UP: >+ case CLK_SPREAD_DOWN: >+ if (!ss_conf->modfreq_hz || !ss_conf->spread_bp || >+ ss_conf->spread_bp > 10000) >+ return -EINVAL; I think sashiko comment is wrong. In [1], we reached an agreement that spread "in permyriad, i.e. 0.01%". So the input value must be the real value * 10000, saying 0.01% * 10000 [1] https://github.com/devicetree-org/dt-schema/pull/154 Regards Peng >+ break; >+ default: >+ return -EINVAL; >+ } >+ > core = hw->core; > > clk_prepare_lock(); >-- >2.43.0 > >