Re: [PATCH v2 1/5] clk: qcom: apss-ipq-pll: drop 'alpha_en_mask' from IPQ5018 PLL config

From: Dmitry Baryshkov
Date: Mon Oct 28 2024 - 17:32:00 EST


On Mon, Oct 28, 2024 at 07:48:15PM +0100, Gabor Juhos wrote:
> Since neither 'alpha' nor 'alpha_hi' is defined in the configuration,
> those will be initialized with zero values implicitly. By using zero
> alpha values, the output rate of the PLL will be the same whether
> alpha mode is enabled or not.
>
> Remove the superfluous initialization of the 'alpha_en_mask' member
> to make it clear that enabling alpha mode is not required to get the
> desired output rate.
>
> Despite that enabling alpha mode is not needed for the initial
> configuration, the set_rate() op might require that it is enabled
> already. In this particular case however, the
> clk_alpha_pll_stromer_set_rate() function will get reset the
> ALPHA_EN bit when the PLL's rate changes, so dropping 'alpha_en_mask'
> is safe.
>
> No functional changes, the initial rate of the PLL is the same both
> before and after the patch.
>
> Tested on TP-Link Archer AX55 v1 (IPQ5018).
>
> Signed-off-by: Gabor Juhos <j4g8y7@xxxxxxxxx>
> ---
> Changes in v2:
> - extend the commit message to indicate that dropping 'alpha_en_mask' is safe
> - Link to v1: https://lore.kernel.org/r/20241021-alpha-mode-cleanup-v1-1-55df8ed73645@xxxxxxxxx
> ---
> drivers/clk/qcom/apss-ipq-pll.c | 1 -
> 1 file changed, 1 deletion(-)
>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

--
With best wishes
Dmitry