RE: [PATCH] Add USB_QUIRK_NO_LPM USB_QUIRK_RESET_RESUME quirks for Dell usb gen 2 device to not fail during enumeration.

From: R, Monish Kumar
Date: Fri May 06 2022 - 01:28:49 EST


Hi greg,

Are you sure you need both? How was this tested that both are actually set?

>> Yes, both NO_LPM and RESET_RESUME quirks were needed.
As the Dell usb gen2 device U1/U2 link states were failing when connected to type-C ports.
Disabling LPM helps to resolve U1/U2 link state failures. However, it leads to resetting the device multiple times. So, added with NO_LPM and RESET_RESUME usb quirks.

Tested multiple hotplug of Dell usb gen 2 device, it passed for all the cases.

Regards,
Monish Kumar R

-----Original Message-----
From: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Sent: 05 May 2022 17:47
To: R, Monish Kumar <monish.kumar.r@xxxxxxxxx>
Cc: olebowle@xxxxxxx; oneukum@xxxxxxxx; vpalatin@xxxxxxxxxxxx; wangjm221@xxxxxxxxx; chris.chiu@xxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Rao, Abhijeet <abhijeet.rao@xxxxxxxxx>
Subject: Re: [PATCH] Add USB_QUIRK_NO_LPM USB_QUIRK_RESET_RESUME quirks for Dell usb gen 2 device to not fail during enumeration.

On Thu, May 05, 2022 at 03:44:59PM +0530, monish.kumar.r@xxxxxxxxx wrote:
> From: Monish Kumar R <monish.kumar.r@xxxxxxxxx>
>
> Signed-off-by: Monish Kumar R <monish.kumar.r@xxxxxxxxx>
> ---
> drivers/usb/core/quirks.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
> index 97b44a68668a..257ac37464e8 100644
> --- a/drivers/usb/core/quirks.c
> +++ b/drivers/usb/core/quirks.c
> @@ -515,6 +515,10 @@ static const struct usb_device_id
> usb_quirk_list[] = {
>
> /* INTEL VALUE SSD */
> { USB_DEVICE(0x8086, 0xf1a5), .driver_info = USB_QUIRK_RESET_RESUME
> },
>
> + /*DELL USB GEN2 */
> + { USB_DEVICE(0x413c, 0xb062), .driver_info = USB_QUIRK_NO_LPM },
> + { USB_DEVICE(0x413c, 0xb062), .driver_info = USB_QUIRK_RESET_RESUME
> +},

Are you sure you need both? How was this tested that both are actually set?

thanks,

greg k-h