My thought was to fix the usbcore rebind issue (with pm_runtime) to let the core unbind and rebind the device's interfaces for drivers with no reset_resume callback (not only btusb). Implementing the btusb reset_resume seems risky, a patch implementing this callback has been previously reverted due to HID dual mode device regression. (cf https://lkml.org/lkml/2013/11/26/347) Regards, Loic Poulain ________________________________________ From: Oliver Neukum [oneukum@xxxxxxx] Sent: Wednesday, March 12, 2014 12:03 PM To: Poulain, Loic Cc: linux-usb@xxxxxxxxxxxxxxx Subject: reset_resume() for btusb Hi, I still think it makes little sense to support reset_resume() in btusb, but if you really want to, you can try this patch. HTH Oliver >From 3776765dbd08701c30f45c1849691a16c1077cc3 Mon Sep 17 00:00:00 2001 From: Oliver Neukum <oneukum@xxxxxxx> Date: Wed, 12 Mar 2014 12:01:13 +0100 Subject: [PATCH] btusb: implement reset_resume() This implements reset_resume() to the extent that this is possible for btusb. It can be done if the HCI is down. In the other cases the host would be thrown out of the network. Signed-off-by: Oliver Neukum <oneukum@xxxxxxx> --- drivers/bluetooth/btusb.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index baeaaed..e56fa2a 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -1670,6 +1670,25 @@ done: return err; } + +static int btusb_reset_resume(struct usb_interface *intf) +{ + struct btusb_data *data = usb_get_intfdata(intf); + struct hci_dev *hdev = data->hdev; + + /* + * the interface can be recovered only if the HCI + * is not part of a network because the synchronization + * is lost as the device is reset + */ + if (test_bit(HCI_RUNNING, &hdev->flags)) + return -EIO; + + if (hdev->setup) + return (hdev->setup)(hdev); + else + return 0; +} #endif static struct usb_driver btusb_driver = { @@ -1679,6 +1698,7 @@ static struct usb_driver btusb_driver = { #ifdef CONFIG_PM .suspend = btusb_suspend, .resume = btusb_resume, + .reset_resume = btusb_reset_resume, #endif .id_table = btusb_table, .supports_autosuspend = 1, -- 1.8.4.5 --------------------------------------------------------------------- Intel Corporation SAS (French simplified joint stock company) Registered headquarters: "Les Montalets"- 2, rue de Paris, 92196 Meudon Cedex, France Registration Number: 302 456 199 R.C.S. NANTERRE Capital: 4,572,000 Euros This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
