On qcom SD host controllers voltage switching be done after the HW is ready for it. The HW informs its readiness through power irq. The voltage switching should happen only then. So added support to register voltage regulators from the msm driver and use them. This patchset was posted long back but not actively pursued https://lore.kernel.org/linux-arm-msm/1539004739-32060-1-git-send-email-vbadigan@xxxxxxxxxxxxxx/ So posting it as fresh patchset. Changes since V4: - Added clear comments on condtion which allows either to tunf off/on Vqmmc or to set load. - Added mmc_card_removable() to the condtion whcih checks if the card is eMMC or other card. - Rerturning error for unsupported voltagtes in sdhci_msm_start_signal_voltage_switch() - Moved setting ios.power_mode to mmc_alloc_host(). Changes since V3: - Dropped reading of regulator load values from device tree. - Dropped documentaiton chagne. - Since only Vqmmc supply of eMMC would be kept On during suspend, setting load only for this regulator so that it can go to LPM. And since this Load reamins same, load value is hard-coded in the driver. Changes since V2: - Removed redundant log from sdhci_msm_set_vmmc. - Added the condition for skiping disabling of vqmmc for eMMC. - Updated logic such that, setting load for vqmmc only if it is kept ON. - Retained ack by Adrian for second patch. - Updated dt properties names as per Robs comments. Changes since V1: - Removed setting load for Vmmc regulator while turning it on/off. Instead setting the active load once during probe. - Simplified handlng of supplies for BUS_ON/OFF cases in shci_msm_handle_pwr_irq(). - Moved common code out of switch case in sdhci_msm_start_signal_voltage_switch(). - Updated variable name to sdhci_core_to_disable_vqmmc. - Updated pr_err logs to dev_err logs. Veerabhadrarao Badiganti (2): mmc: core: Set default power mode in mmc_alloc_host mmc: sdhci-msm: Use internal voltage control Vijay Viswanath (1): mmc: sdhci: Allow platform controlled voltage switching drivers/mmc/core/host.c | 1 + drivers/mmc/host/sdhci-msm.c | 206 +++++++++++++++++++++++++++++++++++++++++-- drivers/mmc/host/sdhci.c | 32 ++++--- drivers/mmc/host/sdhci.h | 1 + 4 files changed, 218 insertions(+), 22 deletions(-) -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc., is a member of Code Aurora Forum, a Linux Foundation Collaborative Project