Re: [PATCH v3 24/31] clk: mediatek: mux: Implement error handling in register API

From: Chun-Jie Chen
Date: Tue Feb 15 2022 - 02:05:29 EST


On Tue, 2022-02-08 at 20:40 +0800, Chen-Yu Tsai wrote:
> The mux clk type registration function does not stop or return errors
> if any clk failed to be registered, nor does it implement an error
> handling path. This may result in a partially working device if any
> step failed.
>
> Make the register function return proper error codes, and bail out if
> errors occur. Proper cleanup, i.e. unregister any clks that were
> successfully registered, is done in the new error path.
>
> Signed-off-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
> Reviewed-by: Miles Chen <miles.chen@xxxxxxxxxxxx>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@xxxxxxxxxxxxx>

Reviewed-by: Chun-Jie Chen <chun-jie.chen@xxxxxxxxxxxx>
> ---
> drivers/clk/mediatek/clk-mux.c | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/mediatek/clk-mux.c
> b/drivers/clk/mediatek/clk-mux.c
> index 70aa42144632..f51e67650f03 100644
> --- a/drivers/clk/mediatek/clk-mux.c
> +++ b/drivers/clk/mediatek/clk-mux.c
> @@ -215,13 +215,26 @@ int mtk_clk_register_muxes(const struct mtk_mux
> *muxes,
>
> if (IS_ERR(clk)) {
> pr_err("Failed to register clk %s: %pe\n", mux-
> >name, clk);
> - continue;
> + goto err;
> }
>
> clk_data->clks[mux->id] = clk;
> }
>
> return 0;
> +
> +err:
> + while (--i >= 0) {
> + const struct mtk_mux *mux = &muxes[i];
> +
> + if (IS_ERR_OR_NULL(clk_data->clks[mux->id]))
> + continue;
> +
> + mtk_clk_unregister_mux(clk_data->clks[mux->id]);
> + clk_data->clks[mux->id] = ERR_PTR(-ENOENT);
> + }
> +
> + return PTR_ERR(clk);
> }
> EXPORT_SYMBOL_GPL(mtk_clk_register_muxes);
>