diff options
| author | Ritesh Harjani <riteshh@codeaurora.org> | 2016-07-19 17:52:25 +0300 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2016-07-25 10:35:02 +0200 |
| commit | ee3206748952046e90cf0dcdcffdbb94839289b4 (patch) | |
| tree | aa0cf00151eedd4c9dc6fc194d11a68fa618d106 /drivers/mmc | |
| parent | 9718f84b85396e090ca42fafa730410d286d61e3 (diff) | |
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 <riteshh@codeaurora.org>
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/sdhci-msm.c | 48 |
1 files changed, 47 insertions, 1 deletions
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 = { |