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Subject: Re: [PATCH] clk: mux: let clk_mux_val_to_index return U8_MAX in the error case
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     linux-clk@vger.kernel.org
To:     Heiner Kallweit <hkallweit1@gmail.com>,
        Michael Turquette <mturquette@baylibre.com>
Date:   Thu, 13 Apr 2023 12:10:23 -0700
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Quoting Heiner Kallweit (2023-04-11 23:19:04)
> Currently this function may return a negative errno, but almost no
> user checks for the error case. Only imx_clk_gpr_mux_get_parent()
> does, but mentions in a comment that they'd prefer a dummy value.
> Other users cast the negative errno to u8 instead, what may result
> in unwanted results.
> Let's deal with this by returning u8 and U8_MAX in the error case.
> Then clk_core_get_parent_by_index() can detect that the index is
> out of range.

Is this causing problems for you?