Another QMI speaking Qualcomm based device, which should be driven by qmi_wwan, while cdc_ether should ignore it.
Like on other Huawei devices, the wwan function can appear either as a single vendor specific interface or as a CDC ECM class function using separate control and data interfaces. The ECM control interface protocol is 0xff, likely in an attempt to indicate that vendor specific management is required. In addition to the near standard CDC class, Huawei also add vendor specific AT management commands to their firmwares. This is probably an attempt to support non-Windows systems using standard class drivers. Unfortunately, this part of the firmware is often buggy. Linux is much better off using whatever native vendor specific management protocol the device offers, and Windows uses, whenever possible. This means QMI in the case of Qualcomm based devices. The E1820 has been verified to work fine with QMI. Matching on interface number is necessary to distiguish the wwan function from serial functions in the single interface mode, as both function types will have class/subclass/function set to ff/ff/ff. The control interface number does not change in CDC ECM mode, so the interface number matching rule is sufficient to handle both modes. The cdc_ether blacklist entry is only relevant in CDC ECM mode, but using a similar interface number based rule helps document this as a transfer from one driver to another. Other Huawei 02/06/ff devices are left with the cdc_ether driver because we do not know whether they are based on Qualcomm chips. The Huawei specific AT command management is known to be somewhat hardware independent, and their usage of these class codes may also be independent of the modem hardware. Reported-by: Graham Inggs <graham.in...@uct.ac.za> Signed-off-by: Bjørn Mork <bj...@mork.no> --- drivers/net/usb/cdc_ether.c | 6 ++++++ drivers/net/usb/qmi_wwan.c | 1 + 2 files changed, 7 insertions(+) diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c index 078795f..04ee044 100644 --- a/drivers/net/usb/cdc_ether.c +++ b/drivers/net/usb/cdc_ether.c @@ -627,6 +627,12 @@ static const struct usb_device_id products [] = { .driver_info = 0, }, +/* Huawei E1820 - handled by qmi_wwan */ +{ + USB_DEVICE_INTERFACE_NUMBER(HUAWEI_VENDOR_ID, 0x14ac, 1), + .driver_info = 0, +}, + /* Realtek RTL8152 Based USB 2.0 Ethernet Adapters */ #if defined(CONFIG_USB_RTL8152) || defined(CONFIG_USB_RTL8152_MODULE) { diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index 86adfa0..d095d0d 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -519,6 +519,7 @@ static const struct usb_device_id products[] = { /* 3. Combined interface devices matching on interface number */ {QMI_FIXED_INTF(0x0408, 0xea42, 4)}, /* Yota / Megafon M100-1 */ {QMI_FIXED_INTF(0x12d1, 0x140c, 1)}, /* Huawei E173 */ + {QMI_FIXED_INTF(0x12d1, 0x14ac, 1)}, /* Huawei E1820 */ {QMI_FIXED_INTF(0x19d2, 0x0002, 1)}, {QMI_FIXED_INTF(0x19d2, 0x0012, 1)}, {QMI_FIXED_INTF(0x19d2, 0x0017, 3)}, -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html