[RFC PATCH 1/4] mmc: core: add cap-enhanced-strobe support
From: Shawn Lin
Date: Wed Mar 02 2016 - 21:44:07 EST
This patch introduce cap-enhanced-strobe for platforms which
want to enable enhanced strobe function from DT if the mmc host
controller claims to support enhanced strobe.
Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/mmc/mmc.txt | 1 +
drivers/mmc/core/host.c | 2 ++
include/linux/mmc/host.h | 6 ++++++
3 files changed, 9 insertions(+)
diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index ed23b9b..51ec979 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -39,6 +39,7 @@ Optional properties:
- cap-power-off-card: powering off the card is safe
- cap-mmc-hw-reset: eMMC hardware reset is supported
- cap-sdio-irq: enable SDIO IRQ signalling on this interface
+- cap-enhanced-strobe: enable enhanced strobe function for emmc v5.1+
- full-pwr-cycle: full power cycle of the card is supported
- mmc-ddr-1_8v: eMMC high-speed DDR mode(1.8V I/O) is supported
- mmc-ddr-1_2v: eMMC high-speed DDR mode(1.2V I/O) is supported
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 1d94607..b49d786 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -270,6 +270,8 @@ int mmc_of_parse(struct mmc_host *host)
host->caps |= MMC_CAP_HW_RESET;
if (of_property_read_bool(np, "cap-sdio-irq"))
host->caps |= MMC_CAP_SDIO_IRQ;
+ if (of_property_read_bool(np, "cap-enhanced-strobe"))
+ host->caps |= MMC_CAP_ENHANCED_STROBE;
if (of_property_read_bool(np, "full-pwr-cycle"))
host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
if (of_property_read_bool(np, "keep-power-in-suspend"))
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 8dd4d29..2a292b3 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -264,6 +264,7 @@ struct mmc_host {
#define MMC_CAP_DRIVER_TYPE_A (1 << 23) /* Host supports Driver Type A */
#define MMC_CAP_DRIVER_TYPE_C (1 << 24) /* Host supports Driver Type C */
#define MMC_CAP_DRIVER_TYPE_D (1 << 25) /* Host supports Driver Type D */
+#define MMC_CAP_ENHANCED_STROBE (1 << 20) /* Host supports enhanced strobe */
#define MMC_CAP_CMD23 (1 << 30) /* CMD23 supported. */
#define MMC_CAP_HW_RESET (1 << 31) /* Hardware reset */
@@ -469,6 +470,11 @@ static inline int mmc_host_uhs(struct mmc_host *host)
MMC_CAP_UHS_DDR50);
}
+static inline int mmc_host_enhanced_strobe(struct mmc_host *host)
+{
+ return host->caps & MMC_CAP_ENHANCED_STROBE;
+}
+
static inline int mmc_host_packed_wr(struct mmc_host *host)
{
return host->caps2 & MMC_CAP2_PACKED_WR;
--
2.3.7