This is a note to let you know that I've just added the patch titled usb: cdc-acm: send zero packet for intel 7260 modem to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-cdc-acm-send-zero-packet-for-intel-7260-modem.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ffdb1e369a73b380fce95b05f8498d92c43842b4 Mon Sep 17 00:00:00 2001 From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Date: Wed, 6 Jan 2016 15:10:04 +0800 Subject: usb: cdc-acm: send zero packet for intel 7260 modem From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> commit ffdb1e369a73b380fce95b05f8498d92c43842b4 upstream. For Intel 7260 modem, it is needed for host side to send zero packet if the BULK OUT size is equal to USB endpoint max packet length. Otherwise, modem side may still wait for more data and cannot give response to host side. Signed-off-by: Konrad Leszczynski <konrad.leszczynski@xxxxxxxxx> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 6 ++++++ drivers/usb/class/cdc-acm.h | 1 + 2 files changed, 7 insertions(+) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1405,6 +1405,8 @@ made_compressed_probe: usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress), NULL, acm->writesize, acm_write_bulk, snd); snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + if (quirks & SEND_ZERO_PACKET) + snd->urb->transfer_flags |= URB_ZERO_PACKET; snd->instance = acm; } @@ -1862,6 +1864,10 @@ static const struct usb_device_id acm_id { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_ACM_PROTO_AT_CDMA) }, + { USB_DEVICE(0x1519, 0x0452), /* Intel 7260 modem */ + .driver_info = SEND_ZERO_PACKET, + }, + { } }; --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -134,3 +134,4 @@ struct acm { #define IGNORE_DEVICE BIT(5) #define QUIRK_CONTROL_LINE_STATE BIT(6) #define CLEAR_HALT_CONDITIONS BIT(7) +#define SEND_ZERO_PACKET BIT(8) Patches currently in stable-queue which might be from baolu.lu@xxxxxxxxxxxxxxx are queue-4.4/usb-xhci-handle-both-ssic-ports-in-pme-stuck-quirk.patch queue-4.4/usb-cdc-acm-send-zero-packet-for-intel-7260-modem.patch queue-4.4/usb-xhci-apply-xhci_pme_stuck_quirk-to-intel-broxton-m-platforms.patch queue-4.4/usb-cdc-acm-handle-unlinked-urb-in-acm-read-callback.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html