From 341fa49fa04aa8afb464c3c102755a56c4d6c2e8 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 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 Signed-off-by: Lu Baolu Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- 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 660c3349ea73..50a38e90e89b 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1237,6 +1237,8 @@ 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; } @@ -1689,6 +1691,10 @@ 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 9af5ad24c7b9..dfd66bb5977a 100644 --- a/drivers/usb/class/cdc-acm.h +++ b/drivers/usb/class/cdc-acm.h @@ -129,3 +129,4 @@ struct acm { #define NO_DATA_INTERFACE 16 #define IGNORE_DEVICE 32 #define CLEAR_HALT_CONDITIONS BIT(7) +#define SEND_ZERO_PACKET BIT(8) -- 2.39.2