ARM: dts: bcm283x: Add dtsi for OTG mode

The Raspberry Pi Zero also supports OTG mode. So provide a dtsi file
to configure the USB interface accordingly. The fifo sizes are optimized
for device endpoint 6 and 7 with the maximum of 768.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

diff --git a/arch/arm/boot/dts/bcm283x-rpi-usb-otg.dtsi b/arch/arm/boot/dts/bcm283x-rpi-usb-otg.dtsi
new file mode 100644 (file)
index 0000000..e7d217c
--- /dev/null
+++ b/arch/arm/boot/dts/bcm283x-rpi-usb-otg.dtsi
@@ -0,0 +1,10 @@
+&usb {
+       dr_mode = "otg";
+       g-rx-fifo-size = <256>;
+       g-np-tx-fifo-size = <32>;
+       /*
+        * According to dwc2 the sum of all device EP
+        * fifo sizes shouldn't exceed 3776 bytes.
+        */
+       g-tx-fifo-size = <256 256 512 512 512 768 768>;
+};