Register writes which change voltage of IO lines or turn the IO bus on/off require sdhc controller to be ready before progressing further. Once a register write which affects IO lines is done, the driver should wait for power irq from controller. Once the irq comes, the driver should acknowledge the irq by writing to power control register. If the acknowledgement is not given to controller, the controller may not complete the corresponding register write action and this can mess up the controller if drivers proceeds without power irq completing. Changes since RFC: wait_for_completion_timeout replaced with wait_event_timeout when waiting for power irq. Removed the spinlock within power irq handler and API which waits for power irq. Added comments to sdhci msm register write functions, warning that they can sleep. Sdhci msm register write functions will do a memory barrier before writing to the register if the particular register can trigger power irq. Instead of enabling SDHCI IO ACCESSORS config in arm64/defconfig, it will be selected in mmc/host/Kconfig if the platform is MMC_SDHCI_MSM. Sahitya Tummala (2): mmc: sdhci-msm: Fix HW issue with power IRQ handling during reset mmc: sdhci-msm: Add support to wait for power irq Subhash Jadavani (1): mmc: sdhci-msm: fix issue with power irq Vijay Viswanath (2): mmc: sdhci-msm: Add ops to do sdhc register write mmc: Kconfig: Enable CONFIG_MMC_SDHCI_IO_ACCESSORS drivers/mmc/host/Kconfig | 1 + drivers/mmc/host/sdhci-msm.c | 253 ++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 249 insertions(+), 5 deletions(-) -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
