[PATCH 5/9] mmc: dw_mmc: return error for invalid voltage setting

[Peng Fan]

On Fri, Oct 17, 2025 at 08:54:10PM +0530, Kaustabh Chakraborty wrote:
>In certain cases, the VQMMC regulator may not support certain voltages.
>For instance, a VQMMC regulator which supports only up to 2.7V will not
>accept 3.3V as an argument. This is unaccounted for, and thus the driver
>incorrectly assumes that the voltage is set successfully.
>
>Fetch the return value in a variable and return if it's non-zero.
>(-ENOSYS is exempted as it implies that the voltage adjustment
>functionality as a whole isn't supported).
>
>Signed-off-by: Kaustabh Chakraborty <kauschluss at disroot.org>

Reviewed-by: Peng Fan <peng.fan at nxp.com>