Return-Path: <0100016308bf007d-2db8a482-febb-4244-81de-e57ac8ba90fe-000000@amazonses.com> Subject: Re: [PATCH] Bluetooth: btusb: Only check needs_reset_resume DMI table for QCA rome chipsets To: Hans de Goede , Marcel Holtmann , Gustavo Padovan , Johan Hedberg Cc: linux-bluetooth@vger.kernel.org, stable@vger.kernel.org, Jeremy Cline References: <20180427092643.27140-1-hdegoede@redhat.com> <0100016307676ed2-fd5830a5-1933-4fc2-b356-a5112a65579f-000000@email.amazonses.com> <55a828e6-01b3-891b-acaa-1bb12aa73a8c@redhat.com> From: Jeremy Cline Message-ID: <0100016308bf007d-2db8a482-febb-4244-81de-e57ac8ba90fe-000000@email.amazonses.com> Date: Fri, 27 Apr 2018 20:15:25 +0000 MIME-Version: 1.0 In-Reply-To: <55a828e6-01b3-891b-acaa-1bb12aa73a8c@redhat.com> Content-Type: text/plain; charset=utf-8 List-ID: On 04/27/2018 02:43 PM, Hans de Goede wrote: > Hi, > > On 04/27/2018 04:00 PM, Jeremy Cline wrote: >> On 04/27/2018 05:26 AM, Hans de Goede wrote: >>> Jeremy Cline correctly points out in rhbz#1514836 that a device where >>> the >>> QCA rome chipset needs the USB_QUIRK_RESET_RESUME quirk, may also ship >>> with a different wifi/bt chipset in some configurations. >>> >>> If that is the case then we are needlessly penalizing those other >>> chipsets >>> with a reset-resume quirk, typically causing 0.4W extra power use >>> because >>> this disables runtime-pm. >>> >>> This commit moves the DMI table check to a >>> btusb_check_needs_reset_resume() >>> helper (so that we can easily also call it for other chipsets) and calls >>> this new helper only for QCA_ROME chipsets for now. >>> >>> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1514836 >>> Cc: stable@vger.kernel.org >>> Cc: Jeremy Cline >>> Suggested-by: Jeremy Cline >>> Signed-off-by: Hans de Goede >>> --- >>>   drivers/bluetooth/btusb.c | 10 +++++++--- >>>   1 file changed, 7 insertions(+), 3 deletions(-) >>> >>> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c >>> index f064984c9ec0..15e7cdca6eb5 100644 >>> --- a/drivers/bluetooth/btusb.c >>> +++ b/drivers/bluetooth/btusb.c >>> @@ -2863,6 +2863,12 @@ static int btusb_config_oob_wake(struct >>> hci_dev *hdev) >>>   } >>>   #endif >>>   +static void btusb_check_needs_reset_resume(struct usb_interface >>> *intf) >>> +{ >>> +    if (dmi_check_system(btusb_needs_reset_resume_table)) >>> +        interface_to_usbdev(intf)->quirks |= USB_QUIRK_RESET_RESUME; >>> +} >>> + >>>   static int btusb_probe(struct usb_interface *intf, >>>                  const struct usb_device_id *id) >>>   { >>> @@ -2985,9 +2991,6 @@ static int btusb_probe(struct usb_interface *intf, >>>       hdev->send   = btusb_send_frame; >>>       hdev->notify = btusb_notify; >>>   -    if (dmi_check_system(btusb_needs_reset_resume_table)) >>> -        interface_to_usbdev(intf)->quirks |= USB_QUIRK_RESET_RESUME; >>> - >>>   #ifdef CONFIG_PM >>>       err = btusb_config_oob_wake(hdev); >>>       if (err) >>> @@ -3076,6 +3079,7 @@ static int btusb_probe(struct usb_interface *intf, >>>           data->setup_on_usb = btusb_setup_qca; >>>           hdev->set_bdaddr = btusb_set_bdaddr_ath3012; >>>           set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks); >>> +        btusb_check_needs_reset_resume(intf); >> >> If we later need the quirk applied to an Intel chipset for a particular >> DMI, this call would get added to the Intel block and then the quirk >> would start getting applied to the Intel variety of the XPS 13 9360 >> again, right? >> >> I have a feeling that's a rather large "if" and I don't have any idea >> how likely it is. Is it even something worth worrying about? > > ATM that seems rather unlikely, but we are tracking the USB-ids to > which the DMI quirks belong (as comments) so we can later switch from > a dmi-id only check to a combined dmi + usb-id check if necessary. Makes sense, thanks. Regards, Jeremy