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| author | Tony Lin <tony.lin@freescale.com> | 2011-08-11 16:45:59 -0400 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2011-08-13 14:50:26 -0400 |
| commit | 0d58864bf3472f8390e0c0a33bd875c7eec868bd (patch) | |
| tree | f186f7e8d753841264497115b6ca599e24079f48 | |
| parent | 55156d240a4d41d47310278c5139e24517f1c65b (diff) | |
| download | op-kernel-dev-0d58864bf3472f8390e0c0a33bd875c7eec868bd.zip op-kernel-dev-0d58864bf3472f8390e0c0a33bd875c7eec868bd.tar.gz | |
mmc: esdhc-imx: fix card interrupt loss on freescale eSDHC
Apply a workaround for the imx eSDHC controller to avoid missing
card interrupts. This makes SDIO work.
Signed-off-by: Tony Lin <tony.lin@freescale.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
| -rw-r--r-- | drivers/mmc/host/sdhci-esdhc-imx.c | 40 |
1 files changed, 31 insertions, 9 deletions
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 9ebfb4b..0e9780f 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -27,6 +27,7 @@ #include "sdhci-pltfm.h" #include "sdhci-esdhc.h" +#define SDHCI_CTRL_D3CD 0x08 /* VENDOR SPEC register */ #define SDHCI_VENDOR_SPEC 0xC0 #define SDHCI_VENDOR_SPEC_SDIO_QUIRK 0x00000002 @@ -141,13 +142,32 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg) struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct pltfm_imx_data *imx_data = pltfm_host->priv; struct esdhc_platform_data *boarddata = &imx_data->boarddata; - - if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE) - && (boarddata->cd_type == ESDHC_CD_GPIO))) - /* - * these interrupts won't work with a custom card_detect gpio - */ - val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT); + u32 data; + + if (unlikely(reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)) { + if (boarddata->cd_type == ESDHC_CD_GPIO) + /* + * These interrupts won't work with a custom + * card_detect gpio (only applied to mx25/35) + */ + val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT); + + if (val & SDHCI_INT_CARD_INT) { + /* + * Clear and then set D3CD bit to avoid missing the + * card interrupt. This is a eSDHC controller problem + * so we need to apply the following workaround: clear + * and set D3CD bit will make eSDHC re-sample the card + * interrupt. In case a card interrupt was lost, + * re-sample it by the following steps. + */ + data = readl(host->ioaddr + SDHCI_HOST_CONTROL); + data &= ~SDHCI_CTRL_D3CD; + writel(data, host->ioaddr + SDHCI_HOST_CONTROL); + data |= SDHCI_CTRL_D3CD; + writel(data, host->ioaddr + SDHCI_HOST_CONTROL); + } + } if (unlikely((imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT) && (reg == SDHCI_INT_STATUS) @@ -217,8 +237,10 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg) */ return; case SDHCI_HOST_CONTROL: - /* FSL messed up here, so we can just keep those two */ - new_val = val & (SDHCI_CTRL_LED | SDHCI_CTRL_4BITBUS); + /* FSL messed up here, so we can just keep those three */ + new_val = val & (SDHCI_CTRL_LED | \ + SDHCI_CTRL_4BITBUS | \ + SDHCI_CTRL_D3CD); /* ensure the endianess */ new_val |= ESDHC_HOST_CONTROL_LE; /* DMA mode bits are shifted */ |
