Commits
Ziyuan Xu committed 649c6059d23
mmc: mmc: Fix HS switch failure in mmc_select_hs400() To slove the issue which was found on gru board for hs400. [ 4.616946] sdhci: Secure Digital Host Controller Interface driver [ 4.623135] sdhci: Copyright(c) Pierre Ossman [ 4.722575] sdhci-pltfm: SDHCI platform and OF driver helper [ 4.730962] sdhci-arasan fe330000.sdhci: No vmmc regulator found [ 4.737444] sdhci-arasan fe330000.sdhci: No vqmmc regulator found [ 4.774930] mmc0: SDHCI controller on fe330000.sdhci [fe330000.sdhci] using ADMA [ 4.980295] mmc0: switch to high-speed from hs200 failed, err:-84 [ 4.986487] mmc0: error -84 whilst initialising MMC card We should change HS400 mode selection timing to meet JEDEC specification. The JEDEC 5.1 said that change the frequency to <= 52MHZ after HS_TIMING switch. Refer to section 6.6.2.3 "HS400" timing mode selection: Set the "Timing Interface" parameter in the HS_TIMING[185] field of the Extended CSD register to 0x1 to switch to High Speed mode and then set the clock frequency to a value not greater than 52MHZ. Signed-off-by: Ziyuan Xu <xzy.xu@rock-chips.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>