UPSTREAM: net: qmi_wwan: increase max QMI message size to 4096

QMI requests exceeding 1500 bytes are possible and
device firmware does not handle fragmented messages
very well.  It is therefore necessary to increase
the maximum message size from the current 512 bytes.

The protocol message size limit is not documented
in any publicly known source, but the out of tree
driver from CodeAurora use 4 kB.  This is therefore
chosen as the new arbitrary default until the real
limit is known.

This should allow any QMI message to be transmitted
without fragmentation, fixing known issues with GPS
assistance data upload.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 3ee2403739db7ec8b683e6451c3401ad716ad5a2)

Change-Id: I36df647599423d9a06f5087fe05d295111e0f737
Signed-off-by: Ben Chan <benchan@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/35027
Reviewed-by: Olof Johansson <olofj@chromium.org>

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index 7e74b20..4d638c4 100644 (file)
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -108,7 +108,7 @@ static int qmi_wwan_register_subdriver(struct usbnet *dev)
        atomic_set(&info->pmcount, 0);
 
        /* register subdriver */
-       subdriver = usb_cdc_wdm_register(info->control, &dev->status->desc, 512, &qmi_wwan_cdc_wdm_manage_power);
+       subdriver = usb_cdc_wdm_register(info->control, &dev->status->desc, 4096, &qmi_wwan_cdc_wdm_manage_power);
        if (IS_ERR(subdriver)) {
                dev_err(&info->control->dev, "subdriver registration failed\n");
                rv = PTR_ERR(subdriver);