[PATCH 06/14] mmc: mmci: Provide option to configure bus signal direction
Ulf Hansson
ulf.hansson at stericsson.com
Mon Dec 5 12:35:52 EST 2011
The ST Micro variant supports bus signal direction indication. A new
member in the variant struct is added for this.
Moreover the actual signal direction configuration is board specific,
thus the amba mmci platform data is extended with a new member to be
able provide mmci with these specific board configurations.
This patch is based upon a patch from Sebastian Rasmussen.
Signed-off-by: Ulf Hansson <ulf.hansson at stericsson.com>
Signed-off-by: Sebastian Rasmussen <sebastian.rasmussen at stericsson.com>
Acked-by: Linus Walleij <linus.walleij at linaro.org>
---
drivers/mmc/host/mmci.c | 21 +++++++++++++++++++++
drivers/mmc/host/mmci.h | 10 ----------
include/linux/amba/mmci.h | 16 ++++++++++++++++
3 files changed, 37 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index a3912cc..d95555e 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -54,6 +54,7 @@ static unsigned int fmax = 515633;
* @st_clkdiv: true if using a ST-specific clock divider algorithm
* @blksz_datactrl16: true if Block size is at b16..b30 position in datactrl register
* @pwrreg_powerup: power up value for MMCIPOWER register
+ * @signal_direction: input/out direction of bus signals can be indicated
*/
struct variant_data {
unsigned int clkreg;
@@ -65,6 +66,7 @@ struct variant_data {
bool st_clkdiv;
bool blksz_datactrl16;
u32 pwrreg_powerup;
+ bool signal_direction;
};
static struct variant_data variant_arm = {
@@ -88,6 +90,7 @@ static struct variant_data variant_u300 = {
.datalength_bits = 16,
.sdio = true,
.pwrreg_powerup = MCI_PWR_ON,
+ .signal_direction = true,
};
static struct variant_data variant_ux500 = {
@@ -99,6 +102,7 @@ static struct variant_data variant_ux500 = {
.sdio = true,
.st_clkdiv = true,
.pwrreg_powerup = MCI_PWR_ON,
+ .signal_direction = true,
};
static struct variant_data variant_ux500v2 = {
@@ -111,6 +115,7 @@ static struct variant_data variant_ux500v2 = {
.st_clkdiv = true,
.blksz_datactrl16 = true,
.pwrreg_powerup = MCI_PWR_ON,
+ .signal_direction = true,
};
/*
@@ -1050,6 +1055,22 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
break;
}
+ if (variant->signal_direction && ios->power_mode != MMC_POWER_OFF) {
+ /*
+ * The ST Micro variant has some additional bits
+ * indicating signal direction for the signals in
+ * the SD/MMC bus and feedback-clock usage.
+ */
+ pwr |= host->plat->sigdir;
+
+ if (ios->bus_width == MMC_BUS_WIDTH_4)
+ pwr &= ~MCI_ST_DATA74DIREN;
+ else if (ios->bus_width == MMC_BUS_WIDTH_1)
+ pwr &= (~MCI_ST_DATA74DIREN &
+ ~MCI_ST_DATA31DIREN &
+ ~MCI_ST_DATA2DIREN);
+ }
+
if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
if (host->hw_designer != AMBA_VENDOR_ST)
pwr |= MCI_ROD;
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index 49f153e..89eb2e3 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -13,16 +13,6 @@
#define MCI_PWR_ON 0x03
#define MCI_OD (1 << 6)
#define MCI_ROD (1 << 7)
-/*
- * The ST Micro version does not have ROD and reuse the voltage registers
- * for direction settings
- */
-#define MCI_ST_DATA2DIREN (1 << 2)
-#define MCI_ST_CMDDIREN (1 << 3)
-#define MCI_ST_DATA0DIREN (1 << 4)
-#define MCI_ST_DATA31DIREN (1 << 5)
-#define MCI_ST_FBCLKEN (1 << 7)
-#define MCI_ST_DATA74DIREN (1 << 8)
#define MMCICLOCK 0x004
#define MCI_CLK_ENABLE (1 << 8)
diff --git a/include/linux/amba/mmci.h b/include/linux/amba/mmci.h
index 2111481..8ce34e8 100644
--- a/include/linux/amba/mmci.h
+++ b/include/linux/amba/mmci.h
@@ -6,6 +6,19 @@
#include <linux/mmc/host.h>
+
+/*
+ * These defines is places here due to access is needed from machine
+ * configuration files. The ST Micro version does not have ROD and
+ * reuse the voltage registers for direction settings.
+ */
+#define MCI_ST_DATA2DIREN (1 << 2)
+#define MCI_ST_CMDDIREN (1 << 3)
+#define MCI_ST_DATA0DIREN (1 << 4)
+#define MCI_ST_DATA31DIREN (1 << 5)
+#define MCI_ST_FBCLKEN (1 << 7)
+#define MCI_ST_DATA74DIREN (1 << 8)
+
/* Just some dummy forwarding */
struct dma_chan;
@@ -30,6 +43,8 @@ struct dma_chan;
* @cd_invert: true if the gpio_cd pin value is active low
* @capabilities: the capabilities of the block as implemented in
* this platform, signify anything MMC_CAP_* from mmc/host.h
+ * @sigdir: a bit field indicating for what bits in the MMC bus the host
+ * should enable signal direction indication.
* @dma_filter: function used to select an appropriate RX and TX
* DMA channel to be used for DMA, if and only if you're deploying the
* generic DMA engine
@@ -52,6 +67,7 @@ struct mmci_platform_data {
int gpio_cd;
bool cd_invert;
unsigned long capabilities;
+ u32 sigdir;
bool (*dma_filter)(struct dma_chan *chan, void *filter_param);
void *dma_rx_param;
void *dma_tx_param;
--
1.7.5.4
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