diff options
| author | Haibo Chen <haibo.chen@nxp.com> | 2017-04-18 18:05:31 +0800 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2017-04-24 21:42:28 +0200 |
| commit | d9370424c9482d0ca2722627309c6f6bae131d97 (patch) | |
| tree | 2f6a8887e53b4bc83158753d04a42f0d11fdf52c /drivers/mmc | |
| parent | a82d12b8d5a626e30d2f15627079abdaa2e77c05 (diff) | |
mmc: sdhci-esdhc-imx: reset tuning circuit when power on mmc card
USDHC tuning circuit should be reset before every time card enumeration
or re-enumeration.
SD3.0 card need tuning. For SDR104 card, when system suspend in standby
mode, and then resume back, the IO timing is still SDR104(tuned) which
may result in card re-enumeration fail in low card speed(400khz) for some
cards. And we did meet the issue that in certain probability, SDR104
card meet mmc command CRC/Timeout error when send CMD2 during mmc bus
resume.
This patch reset the tuning circuit when the ios timing is
MMC_TIMING_LEGACY/MMC_TIMING_MMC_HS/MMC_TIMING_SD_HS, which means both
mmc_power_up() and mmc_power_off() will reset the tuning circuit.
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Acked-by: Dong Aisheng <aisheng.dong@nxp.com>
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-esdhc-imx.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index abad67aeabdd..23d8b8a73ae9 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -889,6 +889,28 @@ static void esdhc_set_strobe_dll(struct sdhci_host *host) } } +static void esdhc_reset_tuning(struct sdhci_host *host) +{ + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host); + u32 ctrl; + + /* Rest the tuning circurt */ + if (esdhc_is_usdhc(imx_data)) { + if (imx_data->socdata->flags & ESDHC_FLAG_MAN_TUNING) { + ctrl = readl(host->ioaddr + ESDHC_MIX_CTRL); + ctrl &= ~ESDHC_MIX_CTRL_SMPCLK_SEL; + ctrl &= ~ESDHC_MIX_CTRL_FBCLK_SEL; + writel(ctrl, host->ioaddr + ESDHC_MIX_CTRL); + writel(0, host->ioaddr + ESDHC_TUNE_CTRL_STATUS); + } else if (imx_data->socdata->flags & ESDHC_FLAG_STD_TUNING) { + ctrl = readl(host->ioaddr + SDHCI_ACMD12_ERR); + ctrl &= ~ESDHC_MIX_CTRL_SMPCLK_SEL; + writel(ctrl, host->ioaddr + SDHCI_ACMD12_ERR); + } + } +} + static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing) { u32 m; @@ -932,6 +954,10 @@ static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing) host->ops->set_clock(host, host->clock); esdhc_set_strobe_dll(host); break; + case MMC_TIMING_LEGACY: + default: + esdhc_reset_tuning(host); + break; } esdhc_change_pinstate(host, timing); |