From ee3206748952046e90cf0dcdcffdbb94839289b4 Mon Sep 17 00:00:00 2001 From: Ritesh Harjani Date: Tue, 19 Jul 2016 17:52:25 +0300 Subject: [PATCH] mmc: sdhci-msm: Add set_uhs_signaling() implementation To allow UHS mode to work properly, we need to implement a Qualcomm specific set_uhs_signaling() callback function. This function differs from the sdhci_set_uhs_signaling() in that we need check the clock rate and enable UHS timing only if the frequency is above 100MHz. This patch resolves the mmc_select_hs200 timeouts noticed after merging commit a5c1f3e55c99 ("mmc: mmc: do not use CMD13 to get status after speed mode switch") mmc0: mmc_select_hs200 failed, error -110 mmc0: error -110 whilst initialising MMC card mmc0: Reset 0x1 never completed. sdhci: =========== REGISTER DUMP (mmc0)=========== sdhci: Sys addr: 0x00000000 | Version: 0x00002e02 sdhci: Blk size: 0x00004000 | Blk cnt: 0x00000000 sdhci: Argument: 0x00000000 | Trn mode: 0x00000000 sdhci: Present: 0x01f80000 | Host ctl: 0x00000000 sdhci: Power: 0x00000000 | Blk gap: 0x00000000 sdhci: Wake-up: 0x00000000 | Clock: 0x00000003 sdhci: Timeout: 0x00000000 | Int stat: 0x00000000 sdhci: Int enab: 0x00000000 | Sig enab: 0x00000000 sdhci: AC12 err: 0x00000000 | Slot int: 0x00000000 sdhci: Caps: 0x322dc8b2 | Caps_1: 0x00008007 sdhci: Cmd: 0x00000000 | Max curr: 0x00000000 sdhci: Host ctl2: 0x00000000 sdhci: ADMA Err: 0x00000000 | ADMA Ptr: 0x0000000000000000 sdhci: =========================================== Fixes: a5c1f3e55c99 ("mmc: mmc: do not use CMD13 to get status after...") Signed-off-by: Ritesh Harjani Signed-off-by: Georgi Djakov Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-msm.c | 48 +++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c index cc4274a023fd..1f59f0008930 100644 --- a/drivers/mmc/host/sdhci-msm.c +++ b/drivers/mmc/host/sdhci-msm.c @@ -410,6 +410,52 @@ retry: return rc; } +static void sdhci_msm_set_uhs_signaling(struct sdhci_host *host, + unsigned int uhs) +{ + struct mmc_host *mmc = host->mmc; + u16 ctrl_2; + + ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2); + /* Select Bus Speed Mode for host */ + ctrl_2 &= ~SDHCI_CTRL_UHS_MASK; + switch (uhs) { + case MMC_TIMING_UHS_SDR12: + ctrl_2 |= SDHCI_CTRL_UHS_SDR12; + break; + case MMC_TIMING_UHS_SDR25: + ctrl_2 |= SDHCI_CTRL_UHS_SDR25; + break; + case MMC_TIMING_UHS_SDR50: + ctrl_2 |= SDHCI_CTRL_UHS_SDR50; + break; + case MMC_TIMING_MMC_HS200: + case MMC_TIMING_UHS_SDR104: + ctrl_2 |= SDHCI_CTRL_UHS_SDR104; + break; + case MMC_TIMING_UHS_DDR50: + case MMC_TIMING_MMC_DDR52: + ctrl_2 |= SDHCI_CTRL_UHS_DDR50; + break; + } + + /* + * When clock frequency is less than 100MHz, the feedback clock must be + * provided and DLL must not be used so that tuning can be skipped. To + * provide feedback clock, the mode selection can be any value less + * than 3'b011 in bits [2:0] of HOST CONTROL2 register. + */ + if (host->clock <= 100000000 && + (uhs == MMC_TIMING_MMC_HS400 || + uhs == MMC_TIMING_MMC_HS200 || + uhs == MMC_TIMING_UHS_SDR104)) + ctrl_2 &= ~SDHCI_CTRL_UHS_MASK; + + dev_dbg(mmc_dev(mmc), "%s: clock=%u uhs=%u ctrl_2=0x%x\n", + mmc_hostname(host->mmc), host->clock, uhs, ctrl_2); + sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2); +} + static const struct of_device_id sdhci_msm_dt_match[] = { { .compatible = "qcom,sdhci-msm-v4" }, {}, @@ -422,7 +468,7 @@ static const struct sdhci_ops sdhci_msm_ops = { .reset = sdhci_reset, .set_clock = sdhci_set_clock, .set_bus_width = sdhci_set_bus_width, - .set_uhs_signaling = sdhci_set_uhs_signaling, + .set_uhs_signaling = sdhci_msm_set_uhs_signaling, }; static const struct sdhci_pltfm_data sdhci_msm_pdata = { -- 2.20.1