diff options
| -rw-r--r-- | src/portable/analog/max3421/hcd_max3421.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/src/portable/analog/max3421/hcd_max3421.c b/src/portable/analog/max3421/hcd_max3421.c index 971dbd62e..621d0d86c 100644 --- a/src/portable/analog/max3421/hcd_max3421.c +++ b/src/portable/analog/max3421/hcd_max3421.c @@ -504,8 +504,15 @@ bool hcd_init(uint8_t rhport, const tusb_rhport_init_t* rh_init) { // reset reg_write(rhport, USBCTL_ADDR, USBCTL_CHIPRES, false); reg_write(rhport, USBCTL_ADDR, 0, false); + // Bound the oscillator-OK wait. On boards where the MAX3421E is only + // soft-reset (CHIPRES) rather than hardware-reset via nRST, OSCOK may never + // latch, which would otherwise hang the host forever (adafruit/circuitpython#10053). + // The oscillator is generally running regardless, so proceed after a timeout. + uint32_t oscok_retries = 200000; while( !(reg_read(rhport, USBIRQ_ADDR, false) & USBIRQ_OSCOK_IRQ) ) { - // wait for oscillator to stabilize + if (--oscok_retries == 0) { + break; + } } // Mode: Host and DP/DM pull down |