Add extra hub_port_reset for MTK USB virtual hub
MTK's USB virtual hub is at a wrong state after a software reset. Thus
hub_port_init times out while waiting for the descriptor, causing a >4s
delay per TPU engine initialization. Adding an extra hub_port_reset seems
to put the hub back to the correct state, and cuts the response time to
<1s to get the descriptor after the reset.
Change-Id: If1e17fe2a71f49784ee0b9e8fc0b16f7d06753ec
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index fa28f23..2c31a47 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4645,6 +4645,16 @@
continue;
}
+ // Extra reset is required for musbfsh-hdrc on software reset.
+ if (udev->config &&
+ strncmp(driver_name, "musbfsh-hdrc", strlen(driver_name)) == 0) {
+ dev_info(&udev->dev, "%s %d: extra reset for musbfsh-hdrc\n",
+ __func__, __LINE__);
+ retval = hub_port_reset(hub, port1, udev, delay, false);
+ if (retval < 0) /* error or disconnect */
+ goto fail;
+ }
+
/* Retry on all errors; some devices are flakey.
* 255 is for WUSB devices, we actually need to use
* 512 (WUSB1.0[4.8.1]).
