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dt-bindings: usb: dwc3: Add snps,host-vbus-glitches-quirk avoid vbus glitch
When DWC3 is set to host mode by programming register DWC3_GCTL, VBUS (or its control signal) will turn on immediately on related Root Hub ports. Then the VBUS will be de-asserted for a little while during xhci reset (conducted by xhci driver) for a little while and back to normal. This VBUS glitch might cause some USB devices emuration fail if kernel boot with them connected. One SW workaround which can fix this is to program all PORTSC[PP] to 0 to turn off VBUS immediately after setting host mode in DWC3 driver(per signal measurement result, it will be too late to do it in xhci-plat.c or xhci.c). Signed-off-by: Ran Wang <ran.wang_1@nxp.com> Reviewed-by: Peter Chen <peter.chen@nxp.com> Signed-off-by: Frank Li <Frank.Li@nxp.com> Link: https://lore.kernel.org/r/20240124152525.3910311-3-Frank.Li@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Documentation/devicetree/bindings/usb/snps,dwc3.yaml

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with an external supply.
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type: boolean
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snps,host-vbus-glitches-quirk:
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description:
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When set, power off all Root Hub ports immediately after
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setting host mode to avoid vbus (negative) glitch happen in later
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xhci reset. And the vbus will back to 5V automatically when reset done.
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type: boolean
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snps,is-utmi-l1-suspend:
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description:
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True when DWC3 asserts output signal utmi_l1_suspend_n, false when

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