On 7/03/25 19:46, Erick Shepherd wrote: >>> The SD spec version 6.0 section 6.4.1.5 requires that Vdd must be >>> lowered to less than 0.5V for a minimum of 1 ms when powering off a >>> card. Increase our wait to 15 ms so that voltage has time to drain down >>> to 0.5V. > >> mmc_power_off() has a delay. So does mmc_power_cycle() > >> Why does this need to be in sdhci? Are you experiencing an >> issue? > > Thank you for taking a look at this. The initial change was made in > mmc_power_off() due to an issue we had with some of our devices > requiring more time for the Vdd to drain below 0.5V. Ulf gave us this > feedback on that change: > >> No, this isn't the proper place of adding more "magic" delays. > >> Instead, make sure the related ->set_ios() callback in the mmc host >> driver deals with this instead. In case it uses an external regulator, >> via the regulator API, then this is something that should be >> controlled with the definition of the regulator. > > Should we take a different approach here? It probably should be dealt with in the ->set_power() callback. Is it one of the PCI devices in sdhci-pci-core.c?
