README: add documentation for CONFIG_USB_ULPI*
Add documentation for CONFIG_USB_ULPI and CONFIG_USB_ULPI_VIEWPORT
configuration options.
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
diff --git a/README b/README
index ff72e47..6fe1e0f 100644
--- a/README
+++ b/README
@@ -1185,6 +1185,14 @@
for your device
- CONFIG_USBD_PRODUCTID 0xFFFF
+- ULPI Layer Support:
+ The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
+ the generic ULPI layer. The generic layer accesses the ULPI PHY
+ via the platform viewport, so you need both the genric layer and
+ the viewport enabled. Currently only Chipidea/ARC based
+ viewport is supported.
+ To enable the ULPI layer support, define CONFIG_USB_ULPI and
+ CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
- MMC Support:
The MMC controller on the Intel PXA is supported. To