From: Roger Quadros rogerq@ti.com
commit b8c9c6fa2002b8fd4a9710f76f80f99c6046d48c upstream.
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: Roger Quadros rogerq@ti.com Acked-by: Felipe Balbi <felipe.balbi@linux/intel.com> Signed-off-by: Tony Lindgren tony@atomide.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm/boot/dts/dra7.dtsi | 1 + 1 file changed, 1 insertion(+)
--- a/arch/arm/boot/dts/dra7.dtsi +++ b/arch/arm/boot/dts/dra7.dtsi @@ -1540,6 +1540,7 @@ dr_mode = "otg"; snps,dis_u3_susphy_quirk; snps,dis_u2_susphy_quirk; + snps,dis_metastability_quirk; }; };