* [PATCH v2 1/1] ARM: mxc: fix card interrupt losing issue on freescale eSDHC
2011-07-28 7:15 [PATCH v2 0/1] ARM: mxc: fix card interrupt losing issue on freescale eSDHC Tony Lin
@ 2011-07-28 7:16 ` Tony Lin
2011-08-03 0:16 ` Chris Ball
0 siblings, 1 reply; 4+ messages in thread
From: Tony Lin @ 2011-07-28 7:16 UTC (permalink / raw)
To: linux-mmc; +Cc: linux-arm-kernel, cjb
apply workaround for imx eSDHC controller to avoid missing
the card interrupt so that SDIO function is workable
Signed-off-by: Tony Lin <tony.lin@freescale.com>
---
drivers/mmc/host/sdhci-esdhc-imx.c | 44 +++++++++++++++++++++++++++--------
1 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 710b706..e62d33f 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -25,6 +25,7 @@
#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
@@ -85,14 +86,35 @@ 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;
-
- if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)
- && (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)))
- /*
- * 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);
+ u32 data;
+
+ if (unlikely(reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)) {
+ if (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)
+ /*
+ * 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 D3CD bit and set D3CD bit to avoid
+ * missing the card interrupt
+ * this is a eSDHC controller problem so that
+ * 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)
@@ -162,8 +184,10 @@ 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 */
--
1.7.0.4
^ permalink raw reply related [flat|nested] 4+ messages in thread