[added to the 4.1 stable tree] usb: cdc-acm: send zero packet for intel 7260 modem

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

This patch has been added to the 4.1 stable tree. If you have any
objections, please let us know.

===============

[ Upstream commit ffdb1e369a73b380fce95b05f8498d92c43842b4 ]

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>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx>
---
 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 2bf51b2..8bfcf20 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1415,6 +1415,8 @@ 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;
 	}
 
@@ -1872,6 +1874,10 @@ 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 b3b6c9d..ac830e0 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)
-- 
2.5.0

--
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



[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]