[PATCH v3 21/31] clk: mediatek: cpumux: Implement error handling in register API

[Chun-Jie Chen]

On Tue, 2022-02-08 at 20:40 +0800, Chen-Yu Tsai wrote:
> The cpumux 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 at chromium.org>
> Reviewed-by: Miles Chen <miles.chen at mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno at collabora.com>

Reviewed-by: Chun-Jie Chen <chun-jie.chen at mediatek.com>
> ---
>  drivers/clk/mediatek/clk-cpumux.c | 15 ++++++++++++++-
>  1 file changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/mediatek/clk-cpumux.c
> b/drivers/clk/mediatek/clk-cpumux.c
> index 658aee789f44..499c60432280 100644
> --- a/drivers/clk/mediatek/clk-cpumux.c
> +++ b/drivers/clk/mediatek/clk-cpumux.c
> @@ -123,13 +123,26 @@ int mtk_clk_register_cpumuxes(struct
> device_node *node,
>  		clk = mtk_clk_register_cpumux(mux, regmap);
>  		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_composite *mux = &clks[i];
> +
> +		if (IS_ERR_OR_NULL(clk_data->clks[mux->id]))
> +			continue;
> +
> +		mtk_clk_unregister_cpumux(clk_data->clks[mux->id]);
> +		clk_data->clks[mux->id] = ERR_PTR(-ENOENT);
> +	}
> +
> +	return PTR_ERR(clk);
>  }
>  
>  void mtk_clk_unregister_cpumuxes(const struct mtk_composite *clks,
> int num,