dt-bindings: mmc: describe new eMMC binding for fixed driver type

Some boards may have to use a certain driver type (or drive strength) to
achieve stable eMMC communication. Describe a binding to set this up via
DT.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Wolfram Sang 2017-10-15 14:46:13 +02:00 committed by Ulf Hansson
parent 2d87ddd7b6
commit f7834cbd90

View File

@ -53,6 +53,9 @@ Optional properties:
- no-sdio: controller is limited to send sdio cmd during initialization - no-sdio: controller is limited to send sdio cmd during initialization
- no-sd: controller is limited to send sd cmd during initialization - no-sd: controller is limited to send sd cmd during initialization
- no-mmc: controller is limited to send mmc cmd during initialization - no-mmc: controller is limited to send mmc cmd during initialization
- fixed-emmc-driver-type: for non-removable eMMC, enforce this driver type.
The value <n> is the driver type as specified in the eMMC specification
(table 206 in spec version 5.1).
*NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line
polarity properties, we have to fix the meaning of the "normal" and "inverted" polarity properties, we have to fix the meaning of the "normal" and "inverted"