[RESEND][PATCH 3/3] usb.c: Add a retry in the usb_prepare_device()
Jason Wessel
jason.wessel at windriver.com
Tue Aug 18 16:34:19 CEST 2020
I have found through testing some USB 2 composite mouse/keyboard
devices do not response to the usb_set_address call immediately
following the port reset. It can take anywhere from 2ms to 20ms.
This patch adds a retry and delay for usb_prepare_device() and allows
all the USB keyboards I tried to function properly.
Signed-off-by: Jason Wessel <jason.wessel at windriver.com>
---
common/usb.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/common/usb.c b/common/usb.c
index 0eb5d40a2d..39bae86a11 100644
--- a/common/usb.c
+++ b/common/usb.c
@@ -1032,6 +1032,7 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read,
struct usb_device *parent)
{
int err;
+ int retry_msec = 0;
/*
* Allocate usb 3.0 device context.
@@ -1054,6 +1055,14 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read,
dev->devnum = addr;
err = usb_set_address(dev); /* set address */
+ /* Retry for old composite keyboard/mouse usb2 hardware */
+ while (err < 0 && retry_msec <= 40) {
+ retry_msec += 20;
+ mdelay(20);
+ err = usb_set_address(dev); /* set address */
+ }
+ if (retry_msec > 0)
+ debug("usb_set_address delay: %i\n", retry_msec);
if (err < 0)
debug("\n usb_set_address return < 0\n");
if (err < 0 && dev->status != 0) {
--
2.17.1
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