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authorTony Lin <tony.lin@freescale.com>2011-08-11 16:45:59 -0400
committerChris Ball <cjb@laptop.org>2011-08-13 14:50:26 -0400
commit0d58864bf3472f8390e0c0a33bd875c7eec868bd (patch)
treef186f7e8d753841264497115b6ca599e24079f48
parent55156d240a4d41d47310278c5139e24517f1c65b (diff)
downloadlinux-stericsson-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.c40
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 9ebfb4b482f5..0e9780f5a4a9 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 */