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usb: Add 1ms delay after first Get Descriptor request

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Logitech Unifying Receiver 046d:c52b bcdDevice 12.10 seems
sensitive about the first Get Descriptor request. If there
are any other requests in the same microframe, the device
reports bogus data, first of the descriptor parts is not
sent to the host. Wait over one microframe duration before
issuing subsequent requests to avoid probe failure with
this device, since it can be used to connect USB keyboards.

Signed-off-by: Marek Vasut <marex@denx.de>
Tested-by: Janne Grunau <j@jannau.net>
This commit is contained in:
Marek Vasut 2022-10-30 23:38:35 +01:00
parent f4917b4933
commit 3406e9d8af
1 changed files with 11 additions and 0 deletions
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11
common/usb.c
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@ -999,6 +999,17 @@ static int usb_setup_descriptor(struct usb_device *dev, bool do_read)
err = get_descriptor_len(dev, 64, 8);
if (err)
return err;
/*
* Logitech Unifying Receiver 046d:c52b bcdDevice 12.10 seems
* sensitive about the first Get Descriptor request. If there
* are any other requests in the same microframe, the device
* reports bogus data, first of the descriptor parts is not
* sent to the host. Wait over one microframe duration here
* (1mS for USB 1.x , 125uS for USB 2.0) to avoid triggering
* the issue.
*/
mdelay(1);
}
dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;