powerpc/85xx: Specify hwconfig usage for USB controller

Specify hwconfig usage for USB mode and phy change

Signed-off-by: Ramneek Mehresh <ramneek.mehresh@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

diff --git a/doc/README.fsl-hwconfig b/doc/README.fsl-hwconfig
index 03fea74..e752505 100644 (file)
--- a/doc/README.fsl-hwconfig
+++ b/doc/README.fsl-hwconfig
@@ -19,3 +19,28 @@ audclk
 
        'audclk:12'
                Select the 12.288MHz clock
+
+usb
+       Specific to boards have USB controller
+
+       This option specifies the following for a USB controller:
+
+               - which controller mode to use
+               - which USB PHY to use
+
+       This is used by generic USB device-tree fixup function to update
+       modified values of phy type and controller mode.
+
+       Also used for configuring multiple USB controllers such that
+       'usbN' (where N is 1, 2, etc. refers to controller no.)
+
+       'phy_type'
+               Select USB phy type: 'utmi' OR 'ulpi'
+
+       'dr_mode'
+               Select USB controller mode: 'host', 'peripheral' OR 'otg'
+
+       Examples:
+               usb1:dr_mode=host;usb2:dr_mode=peripheral'
+
+               usb1:dr_mode=host,phy_type=utmi;usb2:dr_mode=host'