From ffdb1e369a73b380fce95b05f8498d92c43842b4 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Wed, 6 Jan 2016 15:10:04 +0800 Subject: [PATCH] usb: cdc-acm: send zero packet for intel 7260 modem 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 Signed-off-by: Lu Baolu Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.c | 6 ++++++ drivers/usb/class/cdc-acm.h | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 8cd193bbd044..e4c70dce3e7c 100644 --- 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_ids[] = { { 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, + }, + { } }; diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h index dd9af38e7cda..ccfaba9ab4e4 100644 --- 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) -- 2.20.1