Bjørn Mork <bjorn@xxxxxxx> writes:
> Finally, I found my modems (or at least a number of them) again today.
> But I'm sorry to say, that the troublesome Huawei E3372h-153 is still
> giving us a hard time. It does not work with your patch. The symptom is
> the same as earlier: The modem returns MBIM frames with 32bit headers.
>
> So for now, I have to NAK this patch.
>
> I am sure we can find a good solution that makes all of these modems
> work, but I cannot support a patch that breaks previously working
> configurations. Sorry. I'll do a few experiments and see if there is a
> simple fix for this. Otherwise we'll probably have to do the quirk
> game.
This is a proof-of-concept only, but it appears to be working. Please
test with your device(s) too. It's still mostly your code, as you can
see.
If this turns out to work, then I believe we should refactor
cdc_ncm_init() and cdc_ncm_bind_common() to make the whole
initialisation sequence a bit cleaner. And maybe also include
cdc_mbim_bind(). Ideally, the MBIM specific RESET should happen there
instead of "polluting" the NCM driver with MBIM specific code.
But anyway: The sequence that seems to work for both the E3372h-153
and the EM7455 is
USB_CDC_GET_NTB_PARAMETERS
USB_CDC_RESET_FUNCTION
usb_set_interface(dev->udev, 'data interface no', 0);
remaining parts of cdc_ncm_init(), excluding USB_CDC_GET_NTB_PARAMETERS
usb_set_interface(dev->udev, 'data interface no', 'data alt setting');
without any additional delay between the two usb_set_interface() calls.
So the major difference from your patch is that I moved the two control
requests out of cdc_ncm_init() to allow running them _before_ setting
the data interface to altsetting 0.
But maybe I was just lucky. This was barely proof tested. Needs a lot
more testing and cleanups as suggested. I'd appreciate it if you
continued that, as I don't really have any time for it...
FWIW, I also ran a quick test with a D-Link DWM-156A7 (Mediatek MBIM
firmware) and a Huawei E367 (Qualcomm device with early Huawei MBIM
firmware, distinctly different from the E3372h-153 and most other
MBIM devices I've seen)
Bjørn
---
drivers/net/usb/cdc_ncm.c | 48 ++++++++++++++++++++++++++++----------------
include/uapi/linux/usb/cdc.h | 1 +
2 files changed, 32 insertions(+), 17 deletions(-)
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index 877c9516e781..be019cbf1719 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -488,16 +488,6 @@ static int cdc_ncm_init(struct usbnet *dev)
u8 iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
int err;
- err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
- USB_TYPE_CLASS | USB_DIR_IN
- |USB_RECIP_INTERFACE,
- 0, iface_no, &ctx->ncm_parm,
- sizeof(ctx->ncm_parm));
- if (err < 0) {
- dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
- return err; /* GET_NTB_PARAMETERS is required */
- }
-
/* set CRC Mode */
if (cdc_ncm_flags(dev) & USB_CDC_NCM_NCAP_CRC_MODE) {
dev_dbg(&dev->intf->dev, "Setting CRC mode off\n");
@@ -837,12 +827,43 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_
}
}
+ iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
+ temp = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
+ USB_TYPE_CLASS | USB_DIR_IN
+ | USB_RECIP_INTERFACE,
+ 0, iface_no, &ctx->ncm_parm,
+ sizeof(ctx->ncm_parm));
+ if (temp < 0) {
+ dev_err(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
+ goto error; /* GET_NTB_PARAMETERS is required */
+ }
+
+ /* Some modems (e.g. Telit LE922A6) need to reset the MBIM function
+ * or they will fail to work properly.
+ * For details on RESET_FUNCTION request see document
+ * "USB Communication Class Subclass Specification for MBIM"
+ * RESET_FUNCTION should be harmless for all the other MBIM modems
+ */
+ if (cdc_ncm_comm_intf_is_mbim(ctx->control->cur_altsetting)) {
+ temp = usbnet_write_cmd(dev, USB_CDC_RESET_FUNCTION,
+ USB_TYPE_CLASS | USB_DIR_OUT
+ | USB_RECIP_INTERFACE,
+ 0, iface_no, NULL, 0);
+ if (temp < 0)
+ dev_err(&dev->intf->dev, "failed RESET_FUNCTION\n");
+ }
+
iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
/* Reset data interface. Some devices will not reset properly
* unless they are configured first. Toggle the altsetting to
* force a reset
+ * This is applied only to ncm devices, since it has been verified
+ * to cause issues with some MBIM modems (e.g. Telit LE922A6).
+ * MBIM devices reset is achieved using MBIM request RESET_FUNCTION
+ * in cdc_ncm_init
*/
+
usb_set_interface(dev->udev, iface_no, data_altsetting);
temp = usb_set_interface(dev->udev, iface_no, 0);
if (temp) {
@@ -854,13 +875,6 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_
if (cdc_ncm_init(dev))
goto error2;
- /* Some firmwares need a pause here or they will silently fail
- * to set up the interface properly. This value was decided
- * empirically on a Sierra Wireless MC7455 running 02.08.02.00
- * firmware.
- */
- usleep_range(10000, 20000);
-
/* configure data interface */
temp = usb_set_interface(dev->udev, iface_no, data_altsetting);
if (temp) {
diff --git a/include/uapi/linux/usb/cdc.h b/include/uapi/linux/usb/cdc.h
index e2bc417b243b..30258fb229e6 100644
--- a/include/uapi/linux/usb/cdc.h
+++ b/include/uapi/linux/usb/cdc.h
@@ -231,6 +231,7 @@ struct usb_cdc_mbim_extended_desc {
#define USB_CDC_SEND_ENCAPSULATED_COMMAND 0x00
#define USB_CDC_GET_ENCAPSULATED_RESPONSE 0x01
+#define USB_CDC_RESET_FUNCTION 0x05
#define USB_CDC_REQ_SET_LINE_CODING 0x20
#define USB_CDC_REQ_GET_LINE_CODING 0x21
#define USB_CDC_REQ_SET_CONTROL_LINE_STATE 0x22
--
2.10.2
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