Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
[linux-2.6-block.git] / drivers / net / usb / qmi_wwan.c
index a051cedd64bde58179a1cb539b94a888fcd29416..85c983d525270a2190e1332d60f44202fb410536 100644 (file)
@@ -1,6 +1,10 @@
 /*
  * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
  *
+ * The probing code is heavily inspired by cdc_ether, which is:
+ * Copyright (C) 2003-2005 by David Brownell
+ * Copyright (C) 2006 by Ole Andre Vadla Ravnas (ActiveSync)
+ *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * version 2 as published by the Free Software Foundation.
 #include <linux/usb/usbnet.h>
 #include <linux/usb/cdc-wdm.h>
 
-/* The name of the CDC Device Management driver */
-#define DM_DRIVER "cdc_wdm"
-
-/*
- * This driver supports wwan (3G/LTE/?) devices using a vendor
+/* This driver supports wwan (3G/LTE/?) devices using a vendor
  * specific management protocol called Qualcomm MSM Interface (QMI) -
  * in addition to the more common AT commands over serial interface
  * management
  * management protocol is used in place of the standard CDC
  * notifications NOTIFY_NETWORK_CONNECTION and NOTIFY_SPEED_CHANGE
  *
+ * Alternatively, control and data functions can be combined in a
+ * single USB interface.
+ *
  * Handling a protocol like QMI is out of the scope for any driver.
- * It can be exported as a character device using the cdc-wdm driver,
- * which will enable userspace applications ("modem managers") to
- * handle it.  This may be required to use the network interface
- * provided by the driver.
+ * It is exported as a character device using the cdc-wdm driver as
+ * a subdriver, enabling userspace applications ("modem managers") to
+ * handle it.
  *
  * These devices may alternatively/additionally be configured using AT
- * commands on any of the serial interfaces driven by the option driver
- *
- * This driver binds only to the data ("slave") interface to enable
- * the cdc-wdm driver to bind to the control interface.  It still
- * parses the CDC functional descriptors on the control interface to
- *  a) verify that this is indeed a handled interface (CDC Union
- *     header lists it as slave)
- *  b) get MAC address and other ethernet config from the CDC Ethernet
- *     header
- *  c) enable user bind requests against the control interface, which
- *     is the common way to bind to CDC Ethernet Control Model type
- *     interfaces
- *  d) provide a hint to the user about which interface is the
- *     corresponding management interface
+ * commands on a serial interface
  */
 
+/* driver specific data */
+struct qmi_wwan_state {
+       struct usb_driver *subdriver;
+       atomic_t pmcount;
+       unsigned long unused;
+       struct usb_interface *control;
+       struct usb_interface *data;
+};
+
+/* using a counter to merge subdriver requests with our own into a combined state */
+static int qmi_wwan_manage_power(struct usbnet *dev, int on)
+{
+       struct qmi_wwan_state *info = (void *)&dev->data;
+       int rv = 0;
+
+       dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
+
+       if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
+               /* need autopm_get/put here to ensure the usbcore sees the new value */
+               rv = usb_autopm_get_interface(dev->intf);
+               if (rv < 0)
+                       goto err;
+               dev->intf->needs_remote_wakeup = on;
+               usb_autopm_put_interface(dev->intf);
+       }
+err:
+       return rv;
+}
+
+static int qmi_wwan_cdc_wdm_manage_power(struct usb_interface *intf, int on)
+{
+       struct usbnet *dev = usb_get_intfdata(intf);
+
+       /* can be called while disconnecting */
+       if (!dev)
+               return 0;
+       return qmi_wwan_manage_power(dev, on);
+}
+
+/* collect all three endpoints and register subdriver */
+static int qmi_wwan_register_subdriver(struct usbnet *dev)
+{
+       int rv;
+       struct usb_driver *subdriver = NULL;
+       struct qmi_wwan_state *info = (void *)&dev->data;
+
+       /* collect bulk endpoints */
+       rv = usbnet_get_endpoints(dev, info->data);
+       if (rv < 0)
+               goto err;
+
+       /* update status endpoint if separate control interface */
+       if (info->control != info->data)
+               dev->status = &info->control->cur_altsetting->endpoint[0];
+
+       /* require interrupt endpoint for subdriver */
+       if (!dev->status) {
+               rv = -EINVAL;
+               goto err;
+       }
+
+       /* for subdriver power management */
+       atomic_set(&info->pmcount, 0);
+
+       /* register subdriver */
+       subdriver = usb_cdc_wdm_register(info->control, &dev->status->desc, 512, &qmi_wwan_cdc_wdm_manage_power);
+       if (IS_ERR(subdriver)) {
+               dev_err(&info->control->dev, "subdriver registration failed\n");
+               rv = PTR_ERR(subdriver);
+               goto err;
+       }
+
+       /* prevent usbnet from using status endpoint */
+       dev->status = NULL;
+
+       /* save subdriver struct for suspend/resume wrappers */
+       info->subdriver = subdriver;
+
+err:
+       return rv;
+}
+
 static int qmi_wwan_bind(struct usbnet *dev, struct usb_interface *intf)
 {
        int status = -1;
-       struct usb_interface *control = NULL;
        u8 *buf = intf->cur_altsetting->extra;
        int len = intf->cur_altsetting->extralen;
        struct usb_interface_descriptor *desc = &intf->cur_altsetting->desc;
        struct usb_cdc_union_desc *cdc_union = NULL;
        struct usb_cdc_ether_desc *cdc_ether = NULL;
-       u32 required = 1 << USB_CDC_HEADER_TYPE | 1 << USB_CDC_UNION_TYPE;
        u32 found = 0;
-       atomic_t *pmcount = (void *)&dev->data[1];
-
-       atomic_set(pmcount, 0);
+       struct usb_driver *driver = driver_of(intf);
+       struct qmi_wwan_state *info = (void *)&dev->data;
 
-       /*
-        * assume a data interface has no additional descriptors and
-        * that the control and data interface are numbered
-        * consecutively - this holds for the Huawei device at least
-        */
-       if (len == 0 && desc->bInterfaceNumber > 0) {
-               control = usb_ifnum_to_if(dev->udev, desc->bInterfaceNumber - 1);
-               if (!control)
-                       goto err;
+       BUILD_BUG_ON((sizeof(((struct usbnet *)0)->data) < sizeof(struct qmi_wwan_state)));
 
-               buf = control->cur_altsetting->extra;
-               len = control->cur_altsetting->extralen;
-               dev_dbg(&intf->dev, "guessing \"control\" => %s, \"data\" => this\n",
-                       dev_name(&control->dev));
-       }
+       /* require a single interrupt status endpoint for subdriver */
+       if (intf->cur_altsetting->desc.bNumEndpoints != 1)
+               goto err;
 
        while (len > 3) {
                struct usb_descriptor_header *h = (void *)buf;
@@ -142,15 +200,23 @@ next_desc:
        }
 
        /* did we find all the required ones? */
-       if ((found & required) != required) {
+       if (!(found & (1 << USB_CDC_HEADER_TYPE)) ||
+           !(found & (1 << USB_CDC_UNION_TYPE))) {
                dev_err(&intf->dev, "CDC functional descriptors missing\n");
                goto err;
        }
 
-       /* give the user a helpful hint if trying to bind to the wrong interface */
-       if (cdc_union && desc->bInterfaceNumber == cdc_union->bMasterInterface0) {
-               dev_err(&intf->dev, "leaving \"control\" interface for " DM_DRIVER " - try binding to %s instead!\n",
-                       dev_name(&usb_ifnum_to_if(dev->udev, cdc_union->bSlaveInterface0)->dev));
+       /* verify CDC Union */
+       if (desc->bInterfaceNumber != cdc_union->bMasterInterface0) {
+               dev_err(&intf->dev, "bogus CDC Union: master=%u\n", cdc_union->bMasterInterface0);
+               goto err;
+       }
+
+       /* need to save these for unbind */
+       info->control = intf;
+       info->data = usb_ifnum_to_if(dev->udev, cdc_union->bSlaveInterface0);
+       if (!info->data) {
+               dev_err(&intf->dev, "bogus CDC Union: slave=%u\n", cdc_union->bSlaveInterface0);
                goto err;
        }
 
@@ -160,63 +226,29 @@ next_desc:
                usbnet_get_ethernet_addr(dev, cdc_ether->iMACAddress);
        }
 
-       /* success! point the user to the management interface */
-       if (control)
-               dev_info(&intf->dev, "Use \"" DM_DRIVER "\" for QMI interface %s\n",
-                       dev_name(&control->dev));
-
-       /* XXX: add a sysfs symlink somewhere to help management applications find it? */
+       /* claim data interface and set it up */
+       status = usb_driver_claim_interface(driver, info->data, dev);
+       if (status < 0)
+               goto err;
 
-       /* collect bulk endpoints now that we know intf == "data" interface */
-       status = usbnet_get_endpoints(dev, intf);
+       status = qmi_wwan_register_subdriver(dev);
+       if (status < 0) {
+               usb_set_intfdata(info->data, NULL);
+               usb_driver_release_interface(driver, info->data);
+       }
 
 err:
        return status;
 }
 
-/* using a counter to merge subdriver requests with our own into a combined state */
-static int qmi_wwan_manage_power(struct usbnet *dev, int on)
-{
-       atomic_t *pmcount = (void *)&dev->data[1];
-       int rv = 0;
-
-       dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(pmcount), on);
-
-       if ((on && atomic_add_return(1, pmcount) == 1) || (!on && atomic_dec_and_test(pmcount))) {
-               /* need autopm_get/put here to ensure the usbcore sees the new value */
-               rv = usb_autopm_get_interface(dev->intf);
-               if (rv < 0)
-                       goto err;
-               dev->intf->needs_remote_wakeup = on;
-               usb_autopm_put_interface(dev->intf);
-       }
-err:
-       return rv;
-}
-
-static int qmi_wwan_cdc_wdm_manage_power(struct usb_interface *intf, int on)
-{
-       struct usbnet *dev = usb_get_intfdata(intf);
-
-       /* can be called while disconnecting */
-       if (!dev)
-               return 0;
-       return qmi_wwan_manage_power(dev, on);
-}
-
 /* Some devices combine the "control" and "data" functions into a
  * single interface with all three endpoints: interrupt + bulk in and
  * out
- *
- * Setting up cdc-wdm as a subdriver owning the interrupt endpoint
- * will let it provide userspace access to the encapsulated QMI
- * protocol without interfering with the usbnet operations.
-  */
+ */
 static int qmi_wwan_bind_shared(struct usbnet *dev, struct usb_interface *intf)
 {
        int rv;
-       struct usb_driver *subdriver = NULL;
-       atomic_t *pmcount = (void *)&dev->data[1];
+       struct qmi_wwan_state *info = (void *)&dev->data;
 
        /* ZTE makes devices where the interface descriptors and endpoint
         * configurations of two or more interfaces are identical, even
@@ -232,43 +264,39 @@ static int qmi_wwan_bind_shared(struct usbnet *dev, struct usb_interface *intf)
                goto err;
        }
 
-       atomic_set(pmcount, 0);
-
-       /* collect all three endpoints */
-       rv = usbnet_get_endpoints(dev, intf);
-       if (rv < 0)
-               goto err;
-
-       /* require interrupt endpoint for subdriver */
-       if (!dev->status) {
-               rv = -EINVAL;
-               goto err;
-       }
-
-       subdriver = usb_cdc_wdm_register(intf, &dev->status->desc, 512, &qmi_wwan_cdc_wdm_manage_power);
-       if (IS_ERR(subdriver)) {
-               rv = PTR_ERR(subdriver);
-               goto err;
-       }
-
-       /* can't let usbnet use the interrupt endpoint */
-       dev->status = NULL;
-
-       /* save subdriver struct for suspend/resume wrappers */
-       dev->data[0] = (unsigned long)subdriver;
+       /*  control and data is shared */
+       info->control = intf;
+       info->data = intf;
+       rv = qmi_wwan_register_subdriver(dev);
 
 err:
        return rv;
 }
 
-static void qmi_wwan_unbind_shared(struct usbnet *dev, struct usb_interface *intf)
+static void qmi_wwan_unbind(struct usbnet *dev, struct usb_interface *intf)
 {
-       struct usb_driver *subdriver = (void *)dev->data[0];
-
-       if (subdriver && subdriver->disconnect)
-               subdriver->disconnect(intf);
+       struct qmi_wwan_state *info = (void *)&dev->data;
+       struct usb_driver *driver = driver_of(intf);
+       struct usb_interface *other;
+
+       if (info->subdriver && info->subdriver->disconnect)
+               info->subdriver->disconnect(info->control);
+
+       /* allow user to unbind using either control or data */
+       if (intf == info->control)
+               other = info->data;
+       else
+               other = info->control;
+
+       /* only if not shared */
+       if (other && intf != other) {
+               usb_set_intfdata(other, NULL);
+               usb_driver_release_interface(driver, other);
+       }
 
-       dev->data[0] = (unsigned long)NULL;
+       info->subdriver = NULL;
+       info->data = NULL;
+       info->control = NULL;
 }
 
 /* suspend/resume wrappers calling both usbnet and the cdc-wdm
@@ -280,15 +308,15 @@ static void qmi_wwan_unbind_shared(struct usbnet *dev, struct usb_interface *int
 static int qmi_wwan_suspend(struct usb_interface *intf, pm_message_t message)
 {
        struct usbnet *dev = usb_get_intfdata(intf);
-       struct usb_driver *subdriver = (void *)dev->data[0];
+       struct qmi_wwan_state *info = (void *)&dev->data;
        int ret;
 
        ret = usbnet_suspend(intf, message);
        if (ret < 0)
                goto err;
 
-       if (subdriver && subdriver->suspend)
-               ret = subdriver->suspend(intf, message);
+       if (info->subdriver && info->subdriver->suspend)
+               ret = info->subdriver->suspend(intf, message);
        if (ret < 0)
                usbnet_resume(intf);
 err:
@@ -298,33 +326,33 @@ err:
 static int qmi_wwan_resume(struct usb_interface *intf)
 {
        struct usbnet *dev = usb_get_intfdata(intf);
-       struct usb_driver *subdriver = (void *)dev->data[0];
+       struct qmi_wwan_state *info = (void *)&dev->data;
        int ret = 0;
 
-       if (subdriver && subdriver->resume)
-               ret = subdriver->resume(intf);
+       if (info->subdriver && info->subdriver->resume)
+               ret = info->subdriver->resume(intf);
        if (ret < 0)
                goto err;
        ret = usbnet_resume(intf);
-       if (ret < 0 && subdriver && subdriver->resume && subdriver->suspend)
-               subdriver->suspend(intf, PMSG_SUSPEND);
+       if (ret < 0 && info->subdriver && info->subdriver->resume && info->subdriver->suspend)
+               info->subdriver->suspend(intf, PMSG_SUSPEND);
 err:
        return ret;
 }
 
-
 static const struct driver_info        qmi_wwan_info = {
-       .description    = "QMI speaking wwan device",
+       .description    = "WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
 };
 
 static const struct driver_info        qmi_wwan_shared = {
-       .description    = "QMI speaking wwan device with combined interface",
+       .description    = "WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
 };
 
@@ -332,7 +360,7 @@ static const struct driver_info     qmi_wwan_force_int0 = {
        .description    = "Qualcomm WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(0), /* interface whitelist bitmap */
 };
@@ -341,7 +369,7 @@ static const struct driver_info     qmi_wwan_force_int1 = {
        .description    = "Qualcomm WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(1), /* interface whitelist bitmap */
 };
@@ -350,7 +378,7 @@ static const struct driver_info qmi_wwan_force_int2 = {
        .description    = "Qualcomm WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(2), /* interface whitelist bitmap */
 };
@@ -359,7 +387,7 @@ static const struct driver_info     qmi_wwan_force_int3 = {
        .description    = "Qualcomm WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(3), /* interface whitelist bitmap */
 };
@@ -368,7 +396,7 @@ static const struct driver_info     qmi_wwan_force_int4 = {
        .description    = "Qualcomm WWAN/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(4), /* interface whitelist bitmap */
 };
@@ -390,7 +418,7 @@ static const struct driver_info     qmi_wwan_sierra = {
        .description    = "Sierra Wireless wwan/QMI device",
        .flags          = FLAG_WWAN,
        .bind           = qmi_wwan_bind_shared,
-       .unbind         = qmi_wwan_unbind_shared,
+       .unbind         = qmi_wwan_unbind,
        .manage_power   = qmi_wwan_manage_power,
        .data           = BIT(8) | BIT(19), /* interface whitelist bitmap */
 };
@@ -413,7 +441,7 @@ static const struct usb_device_id products[] = {
                .idVendor           = HUAWEI_VENDOR_ID,
                .bInterfaceClass    = USB_CLASS_VENDOR_SPEC,
                .bInterfaceSubClass = 1,
-               .bInterfaceProtocol = 8, /* NOTE: This is the *slave* interface of the CDC Union! */
+               .bInterfaceProtocol = 9, /* CDC Ethernet *control* interface */
                .driver_info        = (unsigned long)&qmi_wwan_info,
        },
        {       /* Vodafone/Huawei K5005 (12d1:14c8) and similar modems */
@@ -421,7 +449,7 @@ static const struct usb_device_id products[] = {
                .idVendor           = HUAWEI_VENDOR_ID,
                .bInterfaceClass    = USB_CLASS_VENDOR_SPEC,
                .bInterfaceSubClass = 1,
-               .bInterfaceProtocol = 56, /* NOTE: This is the *slave* interface of the CDC Union! */
+               .bInterfaceProtocol = 57, /* CDC Ethernet *control* interface */
                .driver_info        = (unsigned long)&qmi_wwan_info,
        },
        {       /* Huawei E392, E398 and possibly others in "Windows mode"
@@ -584,17 +612,7 @@ static struct usb_driver qmi_wwan_driver = {
        .disable_hub_initiated_lpm = 1,
 };
 
-static int __init qmi_wwan_init(void)
-{
-       return usb_register(&qmi_wwan_driver);
-}
-module_init(qmi_wwan_init);
-
-static void __exit qmi_wwan_exit(void)
-{
-       usb_deregister(&qmi_wwan_driver);
-}
-module_exit(qmi_wwan_exit);
+module_usb_driver(qmi_wwan_driver);
 
 MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
 MODULE_DESCRIPTION("Qualcomm MSM Interface (QMI) WWAN driver");