- snps,dis_u2_freeclk_exists_quirk: when set, clear the u2_freeclk_exists
in GUSB2PHYCFG, specify that USB2 PHY doesn't provide
a free-running PHY clock.
- - snps,dis_del_phy_power_chg_quirk: when set core will change PHY power
- from P0 to P1/P2/P3 without delay.
- snps,is-utmi-l1-suspend: true when DWC3 asserts output signal
utmi_l1_suspend_n, false when asserts utmi_sleep_n
- snps,hird-threshold: HIRD threshold