Add vid/pid table to umb(4) allowing matching to alternate config

Some devices present multiple configurations and the one chosen by default
is not always usable - for example, some have an CDC ECM config that does
not work with our cdce(4) - allow overriding to a specific config in those
cases.

From gerhard@ with tweaks to comments by me, ok patrick@

diff --git a/sys/dev/usb/if_umb.c b/sys/dev/usb/if_umb.c
index 1d6eec8..1a8fe9a 100644 (file)
--- a/sys/dev/usb/if_umb.c
+++ b/sys/dev/usb/if_umb.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_umb.c,v 1.37 2021/01/29 17:06:19 sthen Exp $ */
+/*     $OpenBSD: if_umb.c,v 1.38 2021/03/28 12:08:58 sthen Exp $ */
 
 /*
  * Copyright (c) 2016 genua mbH
@@ -224,6 +224,28 @@ const struct cfattach umb_ca = {
 
 int umb_delay = 4000;
 
+/*
+ * Normally, MBIM devices are detected by their interface class and subclass.
+ * But for some models that have multiple configurations, it is better to
+ * match by vendor and product id so that we can select the desired
+ * configuration ourselves, e.g. to override a class-based match to another
+ * driver.
+ *
+ * OTOH, some devices identify themselves as an MBIM device but fail to speak
+ * the MBIM protocol.
+ */
+struct umb_products {
+       struct usb_devno         dev;
+       int                      confno;
+};
+const struct umb_products umb_devs[] = {
+       { { USB_VENDOR_DELL, USB_PRODUCT_DELL_DW5821E }, 2 },
+       { { USB_VENDOR_HUAWEI, USB_PRODUCT_HUAWEI_ME906S }, 3 },
+};
+
+#define umb_lookup(vid, pid)           \
+       ((const struct umb_products *)usb_lookup(umb_devs, vid, pid))
+
 /*
  * These devices require an "FCC Authentication" command.
  */
@@ -263,6 +285,8 @@ umb_match(struct device *parent, void *match, void *aux)
        struct usb_attach_arg *uaa = aux;
        usb_interface_descriptor_t *id;
 
+       if (umb_lookup(uaa->vendor, uaa->product) != NULL)
+               return UMATCH_VENDOR_PRODUCT;
        if (!uaa->iface)
                return UMATCH_NONE;
        if ((id = usbd_get_interface_descriptor(uaa->iface)) == NULL)
@@ -315,6 +339,43 @@ umb_attach(struct device *parent, struct device *self, void *aux)
        sc->sc_ctrl_ifaceno = uaa->ifaceno;
        ml_init(&sc->sc_tx_ml);
 
+       if (uaa->configno < 0) {
+               /*
+                * In case the device was matched by VID/PID instead of
+                * InterfaceClass/InterfaceSubClass, we have to pick the
+                * correct configuration ourself.
+                */
+               uaa->configno = umb_lookup(uaa->vendor, uaa->product)->confno;
+               DPRINTF("%s: switching to config #%d\n", DEVNAM(sc),
+                   uaa->configno);
+               status = usbd_set_config_no(sc->sc_udev, uaa->configno, 1);
+               if (status) {
+                       printf("%s: failed to switch to config #%d: %s\n",
+                           DEVNAM(sc), uaa->configno, usbd_errstr(status));
+                       goto fail;
+               }
+               usbd_delay_ms(sc->sc_udev, 200);
+
+               /*
+                * Need to do some manual setups that usbd_probe_and_attach()
+                * would do for us otherwise.
+                */
+               uaa->nifaces = uaa->device->cdesc->bNumInterfaces;
+               for (i = 0; i < uaa->nifaces; i++) {
+                       if (usbd_iface_claimed(sc->sc_udev, i))
+                               continue;
+                       id = usbd_get_interface_descriptor(&uaa->device->ifaces[i]);
+                       if (id != NULL && id->bInterfaceClass == UICLASS_CDC &&
+                           id->bInterfaceSubClass ==
+                           UISUBCLASS_MOBILE_BROADBAND_INTERFACE_MODEL) {
+                               uaa->iface = &uaa->device->ifaces[i];
+                               uaa->ifaceno = uaa->iface->idesc->bInterfaceNumber;
+                               sc->sc_ctrl_ifaceno = uaa->ifaceno;
+                               break;
+                       }
+               }
+       }
+
        /*
         * Some MBIM hardware does not provide the mandatory CDC Union
         * Descriptor, so we also look at matching Interface
@@ -382,9 +443,9 @@ umb_attach(struct device *parent, struct device *self, void *aux)
        for (i = 0; i < uaa->nifaces; i++) {
                if (usbd_iface_claimed(sc->sc_udev, i))
                        continue;
-               id = usbd_get_interface_descriptor(uaa->ifaces[i]);
+               id = usbd_get_interface_descriptor(&sc->sc_udev->ifaces[i]);
                if (id != NULL && id->bInterfaceNumber == data_ifaceno) {
-                       sc->sc_data_iface = uaa->ifaces[i];
+                       sc->sc_data_iface = &sc->sc_udev->ifaces[i];
                        usbd_claim_iface(sc->sc_udev, i);
                }
        }