[PATCH 1/3] Documentation: mmc: Document mmc aliases

From: Douglas Anderson
Date: Thu Apr 28 2016 - 19:08:23 EST


From: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>

Now, index of mmc/mmcblk devices is allocated in accordance with probing
time. If want to use the mmcblk1 for some device, it can use alias.

aliases {
mmc0 = &mmc0; /* mmc0/mmcblk0 for eMMC */
mmc1 = &mmc2; /* mmc1/mmcblk1 for SD */
mmc2 = &mmc1; /* mmc2/mmcblk2 for SDIO*/
};

If there are no corresponding values, it might be allocated with
existing scheme.

Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
[dianders: just bindings now; mention mmc not just mmcblk]
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
Documentation/devicetree/bindings/mmc/mmc.txt | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt
index a1ed9c4e7235..d225a7fb3849 100644
--- a/Documentation/devicetree/bindings/mmc/mmc.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc.txt
@@ -72,6 +72,10 @@ Optional SDIO properties:
- wakeup-source: Enables wake up of host system on SDIO IRQ assertion
(Legacy property supported: "enable-sdio-wakeup")

+Aliases (Optional):
+- If you want to use the fixed index for devices like mmcX / mmcblkX, should
+be represented in the aliases node using following format "mmc(X)".
+(X is an unique number for the alias.)

MMC power sequences:
--------------------
@@ -146,3 +150,10 @@ mmc3: mmc@01c12000 {
interrupt-names = "host-wake";
};
};
+
+Example with aliases nodes:
+
+aliases {
+ mmc0 = &mmc0; /* Fixed to mmc0/mmcblk0 for &mmc0 */
+ mmc1 = &mmc2; /* Fixed to mmc1/mmcblk1 for &mmc2 */
+};
--
2.8.0.rc3.226.g39d4020