[PATCH 2/3] mmc: Add OF bindings support for mmc host controller capabilities

[thomas.abraham@linaro.org (Thomas Abraham)]

Device nodes representing sd/mmc controllers in a device tree would include
mmc host controller capabilities. Add support for parsing of mmc host
controller capabilities included in device nodes.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
---
 .../devicetree/bindings/mmc/linux-mmc-host.txt     |   11 +++++++
 drivers/mmc/core/host.c                            |   31 ++++++++++++++++++++
 include/linux/mmc/host.h                           |    3 ++
 3 files changed, 45 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/mmc/linux-mmc-host.txt

diff --git a/Documentation/devicetree/bindings/mmc/linux-mmc-host.txt b/Documentation/devicetree/bindings/mmc/linux-mmc-host.txt
new file mode 100644
index 0000000..cb43905
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/linux-mmc-host.txt
@@ -0,0 +1,11 @@
+* Linux mmc host capabilities
+
+MMC Host Controller capabilities used in linux:
+- linux,mmc_cap_4_bit_data - host can do 4 bit transfers
+- linux,mmc_cap_mmc_highspeed - host can do MMC high-speed timing
+- linux,mmc_cap_sd_highspeed - host can do SD high-speed timing
+- linux,mmc_cap_needs_poll - host needs polling for card detection
+- linux,mmc_cap_8_bit_data - host can do 8 bit transfer
+- linux,mmc_cap_disable - host can be disabled
+- linux,mmc_cap_nonremovable - host is connected to nonremovable media
+- linux,mmc_cap_erase - host allows erase/trim commands
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 793d0a0..4ee2e43 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -19,6 +19,7 @@
 #include <linux/leds.h>
 #include <linux/slab.h>
 #include <linux/suspend.h>
+#include <linux/of.h>
 
 #include <linux/mmc/host.h>
 #include <linux/mmc/card.h>
@@ -385,3 +386,33 @@ void mmc_free_host(struct mmc_host *host)
 }
 
 EXPORT_SYMBOL(mmc_free_host);
+
+#ifdef CONFIG_OF
+/**
+ *	mmc_of_parse_host_caps - parse mmc host capabilities from device node
+ *	@np: pointer to device node in device tree
+ *	@caps: pointer to host caps value to be returned
+ *
+ *	Search the device node in device tree for mmc host capabilities.
+ */
+void mmc_of_parse_host_caps(struct device_node *np, unsigned long *caps)
+{
+	if (of_find_property(np, "linux,mmc_cap_4_bit_data", NULL))
+		*caps |= MMC_CAP_4_BIT_DATA;
+	if (of_find_property(np, "linux,mmc_cap_mmc_highspeed", NULL))
+		*caps |= MMC_CAP_MMC_HIGHSPEED;
+	if (of_find_property(np, "linux,mmc_cap_sd_highspeed", NULL))
+		*caps |= MMC_CAP_SD_HIGHSPEED;
+	if (of_find_property(np, "linux,mmc_cap_needs_poll", NULL))
+		*caps |= MMC_CAP_NEEDS_POLL;
+	if (of_find_property(np, "linux,mmc_cap_8_bit_data", NULL))
+		*caps |= MMC_CAP_8_BIT_DATA;
+	if (of_find_property(np, "linux,mmc_cap_disable", NULL))
+		*caps |= MMC_CAP_DISABLE;
+	if (of_find_property(np, "linux,mmc_cap_nonremovable", NULL))
+		*caps |= MMC_CAP_NONREMOVABLE;
+	if (of_find_property(np, "linux,mmc_cap_erase", NULL))
+		*caps |= MMC_CAP_ERASE;
+}
+EXPORT_SYMBOL(mmc_of_parse_host_caps);
+#endif /* CONFIG_OF */
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 1d09562..72b5df2 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -309,6 +309,9 @@ extern struct mmc_host *mmc_alloc_host(int extra, struct device *);
 extern int mmc_add_host(struct mmc_host *);
 extern void mmc_remove_host(struct mmc_host *);
 extern void mmc_free_host(struct mmc_host *);
+#ifdef CONFIG_OF
+extern void mmc_of_parse_host_caps(struct device_node *np, unsigned long *caps);
+#endif
 
 static inline void *mmc_priv(struct mmc_host *host)
 {
-- 
1.6.6.rc2