diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt index dd0eba0c342b..95e516c1a4b7 100644 --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt @@ -38,6 +38,22 @@ Optional properties: be specified. - phy-clkgate-delay-us: the delay time (us) between putting the PHY into low power mode and gating the PHY clock. +- non-zero-ttctrl-ttha: after setting this property, the value of register + ttctrl.ttha will be 0x7f; if not, the value will be 0x0, this is the default + value. It needs to be very carefully for setting this property, it is + recommended that consult with your IC engineer before setting this value. + On the most of chipidea platforms, the "usage_tt" flag at RTL is 0, so this + property only affects siTD. + If this property is not set, the max packet size is 1023 bytes, and if + the total of packet size for pervious transactions are more than 256 bytes, + it can't accept any transactions within this frame. The use case is single + transaction, but higher frame rate. + If this property is set, the max packet size is 188 bytes, it can handle + more transactions than above case, it can accept transactions until it + considers the left room size within frame is less than 188 bytes, software + needs to make sure it does not send more than 90% + maximum_periodic_data_per_frame. The use case is multiple transactions, but + less frame rate. i.mx specific properties - fsl,usbmisc: phandler of non-core register device, with one |