[PATCH 1/3] usb: dwc3: Add reference clock properties
From: Thinh Nguyen <thinh.nguyen@synopsys.com>
Date: 2018-11-03 01:35:45
Also in:
linux-usb
Subsystem:
open firmware and flattened device tree bindings, the rest, usb subsystem · Maintainers:
Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds, Greg Kroah-Hartman
Add two new device properties to program the reference clock period and to enable low power management using the reference clock. This allows a higher demand to go in low power for Audio Device Class devices. This feature is currently only valid for DWC_usb31 peripheral controller v1.80a and higher. Set "snps,refclk-period-ns" to program the reference clock period. The valid input periods are as follow: +-------------+-----------------+ | Period (ns) | Freq (MHz) | +-------------+-----------------+ | 25 | 39.7/40 | | 41 | 24.4 | | 50 | 20 | | 52 | 19.2 | | 58 | 17.2 | | 62 | 16.1 | +-------------+-----------------+ Set "snps,refclk-lpm" to enable low power scheduling of isochronous transfers by running SOF/ITP counters using the reference clock. Both "snps,dis_u2_susphy_quirk" and "snps,dis_enblslpm_quirk" must not be set for this feature to be enabled. Signed-off-by: Thinh Nguyen <redacted> --- Documentation/devicetree/bindings/usb/dwc3.txt | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)
diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
index 636630fb92d7..712b344c3a31 100644
--- a/Documentation/devicetree/bindings/usb/dwc3.txt
+++ b/Documentation/devicetree/bindings/usb/dwc3.txt@@ -95,6 +95,24 @@ Optional properties: this and tx-thr-num-pkt-prd to a valid, non-zero value 1-16 (DWC_usb31 programming guide section 1.2.3) to enable periodic ESS TX threshold. + - snps,refclk-period-ns: set to program the reference clock period. The valid + input periods are as follow: + +-------------+-----------------+ + | Period (ns) | Freq (MHz) | + +-------------+-----------------+ + | 25 | 39.7/40 | + | 41 | 24.4 | + | 50 | 20 | + | 52 | 19.2 | + | 58 | 17.2 | + | 62 | 16.1 | + +-------------+-----------------+ + - snps,enable-refclk-lpm: set to enable low power scheduling of isochronous + transfers by running SOF/ITP counters using the + reference clock. Only valid for DWC_usb31 peripheral + controller v1.80a and higher. Both + "snps,dis_u2_susphy_quirk" and + "snps,dis_enblslpm_quirk" must not be set. - <DEPRECATED> tx-fifo-resize: determines if the FIFO *has* to be reallocated. - snps,incr-burst-type-adjustment: Value for INCR burst type of GSBUSCFG0
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2.11.0