• Roger Quadros's avatar
    ARM: dts: dra7: Disable USB metastability workaround for USB2 · b8c9c6fa
    Roger Quadros authored
    The metastability workaround causes Erratic errors [1]
    on the HighSpeed USB PHY which can cause upto 2 seconds
    delay in enumerating to a USB host while in Gadget mode.
    
    Disable the Run/Stop metastability workaround to avoid this
    ill effect. We are aware that this opens up the opportunity
    for Run/Stop metastability, however this issue has never been
    observed in TI releases so we think that Run/Stop metastability
    is a lesser evil than the PHY Erratic errors. So disable it.
    
    [1] USB controller trace during gadget enumeration
        irq/90-dwc3-969   [000] d...    52.323145: dwc3_event: event
        (00000901): Erratic Error [U0]
        irq/90-dwc3-969   [000] d...    52.560646: dwc3_event: event
        (00000901): Erratic Error [U0]
        irq/90-dwc3-969   [000] d...    52.798144: dwc3_event: event
        (00000901): Erratic Error [U0]
    Signed-off-by: default avatarRoger Quadros <rogerq@ti.com>
    Acked-by: default avatarFelipe Balbi <felipe.balbi@linux/intel.com>
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
    b8c9c6fa
dra7.dtsi 54.4 KB