omap: RX51: Remux to pull eMMC lines down when powering off
It has been discovered that, when eMMC is powered off, current
will flow from OMAP eMMC data pull-ups to the eMMC voltage supply.
Configuring pads for OMAP off-mode does not help because eMMC is
powered off independently of OMAP off-mode. Hence the pads are
now re-configured when eMMC is powered on or off.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/board-rx51-peripherals.c b/arch/arm/mach-omap2/board-rx51-peripherals.c
index ab07ca2..4377a4c 100644
--- a/arch/arm/mach-omap2/board-rx51-peripherals.c
+++ b/arch/arm/mach-omap2/board-rx51-peripherals.c
@@ -209,6 +209,46 @@
.irq_line = 1,
};
+/* Enable input logic and pull all lines up when eMMC is on. */
+static struct omap_board_mux rx51_mmc2_on_mux[] = {
+ OMAP3_MUX(SDMMC2_CMD, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT0, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT1, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT2, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT3, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT4, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT5, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT6, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT7, OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0),
+ { .reg_offset = OMAP_MUX_TERMINATOR },
+};
+
+/* Disable input logic and pull all lines down when eMMC is off. */
+static struct omap_board_mux rx51_mmc2_off_mux[] = {
+ OMAP3_MUX(SDMMC2_CMD, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT0, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT1, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT2, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT3, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT4, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT5, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT6, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ OMAP3_MUX(SDMMC2_DAT7, OMAP_PULL_ENA | OMAP_MUX_MODE0),
+ { .reg_offset = OMAP_MUX_TERMINATOR },
+};
+
+/*
+ * Current flows to eMMC when eMMC is off and the data lines are pulled up,
+ * so pull them down. N.B. we pull 8 lines because we are using 8 lines.
+ */
+static void rx51_mmc2_remux(struct device *dev, int slot, int power_on)
+{
+ if (power_on)
+ omap_mux_write_array(rx51_mmc2_on_mux);
+ else
+ omap_mux_write_array(rx51_mmc2_off_mux);
+}
+
static struct omap2_hsmmc_info mmc[] __initdata = {
{
.name = "external",
@@ -222,11 +262,12 @@
{
.name = "internal",
.mmc = 2,
- .wires = 8,
+ .wires = 8, /* See also rx51_mmc2_remux */
.gpio_cd = -EINVAL,
.gpio_wp = -EINVAL,
.nonremovable = true,
.power_saving = true,
+ .remux = rx51_mmc2_remux,
},
{} /* Terminator */
};
diff --git a/arch/arm/mach-omap2/hsmmc.c b/arch/arm/mach-omap2/hsmmc.c
index cc7e77f..4a05c37 100644
--- a/arch/arm/mach-omap2/hsmmc.c
+++ b/arch/arm/mach-omap2/hsmmc.c
@@ -48,6 +48,9 @@
u32 reg, prog_io;
struct omap_mmc_platform_data *mmc = dev->platform_data;
+ if (mmc->slots[0].remux)
+ mmc->slots[0].remux(dev, slot, power_on);
+
/*
* Assume we power both OMAP VMMC1 (for CMD, CLK, DAT0..3) and the
* card with Vcc regulator (from twl4030 or whatever). OMAP has both
@@ -121,6 +124,9 @@
{
struct omap_mmc_platform_data *mmc = dev->platform_data;
+ if (mmc->slots[0].remux)
+ mmc->slots[0].remux(dev, slot, power_on);
+
if (power_on) {
/* Only MMC2 supports a CLKIN */
if (mmc->slots[0].internal_clock) {
@@ -185,6 +191,8 @@
mmc->slots[0].switch_pin = c->gpio_cd;
mmc->slots[0].gpio_wp = c->gpio_wp;
+ mmc->slots[0].remux = c->remux;
+
if (c->cover_only)
mmc->slots[0].cover = 1;
diff --git a/arch/arm/mach-omap2/hsmmc.h b/arch/arm/mach-omap2/hsmmc.h
index e946b5f7..f641f59 100644
--- a/arch/arm/mach-omap2/hsmmc.h
+++ b/arch/arm/mach-omap2/hsmmc.h
@@ -19,6 +19,8 @@
char *name; /* or NULL for default */
struct device *dev; /* returned: pointer to mmc adapter */
int ocr_mask; /* temporary HACK */
+ /* Remux (pad configuation) when powering on/off */
+ void (*remux)(struct device *dev, int slot, int power_on);
};
#if defined(CONFIG_MMC_OMAP_HS) || defined(CONFIG_MMC_OMAP_HS_MODULE)