1 files changed, 93 insertions, 46 deletions

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 1160c55de7f2..7b5cc16e4a0b 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -24,6 +24,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/device.h>
+#include <linux/utsname.h>
 
 #include <linux/usb/composite.h>
 
@@ -39,6 +40,7 @@
 #define USB_BUFSIZ      1024
 
 static struct usb_composite_driver *composite;
+static int (*composite_gadget_bind)(struct usb_composite_dev *cdev);
 
 /* Some systems will need runtime overrides for the  product identifers
  * published in the device descriptor, either numbers or strings or both.
@@ -69,6 +71,8 @@ static char *iSerialNumber;
 module_param(iSerialNumber, charp, 0);
 MODULE_PARM_DESC(iSerialNumber, "SerialNumber string");
 
+static char composite_manufacturer[50];
+
 /*-------------------------------------------------------------------------*/
 
 /**
@@ -470,18 +474,20 @@ done:
  * usb_add_config() - add a configuration to a device.
  * @cdev: wraps the USB gadget
  * @config: the configuration, with bConfigurationValue assigned
+ * @bind: the configuration's bind function
  * Context: single threaded during gadget setup
  *
- * One of the main tasks of a composite driver's bind() routine is to
+ * One of the main tasks of a composite @bind() routine is to
  * add each of the configurations it supports, using this routine.
  *
- * This function returns the value of the configuration's bind(), which
+ * This function returns the value of the configuration's @bind(), which
  * is zero for success else a negative errno value.  Binding configurations
  * assigns global resources including string IDs, and per-configuration
  * resources such as interface IDs and endpoints.
  */
 int usb_add_config(struct usb_composite_dev *cdev,
-                struct usb_configuration *config)
+                struct usb_configuration *config,
+                int (*bind)(struct usb_configuration *))
 {
         int                             status = -EINVAL;
         struct usb_configuration        *c;
@@ -490,7 +496,7 @@ int usb_add_config(struct usb_composite_dev *cdev,
                         config->bConfigurationValue,
                         config->label, config);
 
-        if (!config->bConfigurationValue || !config->bind)
+        if (!config->bConfigurationValue || !bind)
                 goto done;
 
         /* Prevent duplicate configuration identifiers */
@@ -507,7 +513,7 @@ int usb_add_config(struct usb_composite_dev *cdev,
         INIT_LIST_HEAD(&config->functions);
         config->next_interface_id = 0;
 
-        status = config->bind(config);
+        status = bind(config);
         if (status < 0) {
                 list_del(&config->list);
                 config->cdev = NULL;
@@ -533,7 +539,7 @@ int usb_add_config(struct usb_composite_dev *cdev,
                 }
         }
 
-        /* set_alt(), or next config->bind(), sets up
+        /* set_alt(), or next bind(), sets up
          * ep->driver_data as needed.
          */
         usb_ep_autoconfig_reset(cdev->gadget);
@@ -599,6 +605,7 @@ static int get_string(struct usb_composite_dev *cdev,
         struct usb_configuration        *c;
         struct usb_function             *f;
         int                             len;
+        const char                      *str;
 
         /* Yes, not only is USB's I18N support probably more than most
          * folk will ever care about ... also, it's all supported here.
@@ -638,9 +645,29 @@ static int get_string(struct usb_composite_dev *cdev,
                 return s->bLength;
         }
 
-        /* Otherwise, look up and return a specified string.  String IDs
-         * are device-scoped, so we look up each string table we're told
-         * about.  These lookups are infrequent; simpler-is-better here.
+        /* Otherwise, look up and return a specified string.  First
+         * check if the string has not been overridden.
+         */
+        if (cdev->manufacturer_override == id)
+                str = iManufacturer ?: composite->iManufacturer ?:
+                        composite_manufacturer;
+        else if (cdev->product_override == id)
+                str = iProduct ?: composite->iProduct;
+        else if (cdev->serial_override == id)
+                str = iSerialNumber;
+        else
+                str = NULL;
+        if (str) {
+                struct usb_gadget_strings strings = {
+                        .language = language,
+                        .strings  = &(struct usb_string) { 0xff, str }
+                };
+                return usb_gadget_get_string(&strings, 0xff, buf);
+        }
+
+        /* String IDs are device-scoped, so we look up each string
+         * table we're told about.  These lookups are infrequent;
+         * simpler-is-better here.
          */
         if (composite->strings) {
                 len = lookup_string(composite->strings, buf, language, id);
@@ -901,7 +928,8 @@ unknown:
                  */
                 switch (ctrl->bRequestType & USB_RECIP_MASK) {
                 case USB_RECIP_INTERFACE:
-                        f = cdev->config->interface[intf];
+                        if (cdev->config)
+                                f = cdev->config->interface[intf];
                         break;
 
                 case USB_RECIP_ENDPOINT:
@@ -1025,26 +1053,17 @@ composite_unbind(struct usb_gadget *gadget)
         composite = NULL;
 }
 
-static void
-string_override_one(struct usb_gadget_strings *tab, u8 id, const char *s)
+static u8 override_id(struct usb_composite_dev *cdev, u8 *desc)
 {
-        struct usb_string               *str = tab->strings;
-
-        for (str = tab->strings; str->s; str++) {
-                if (str->id == id) {
-                        str->s = s;
-                        return;
-                }
+        if (!*desc) {
+                int ret = usb_string_id(cdev);
+                if (unlikely(ret < 0))
+                        WARNING(cdev, "failed to override string ID\n");
+                else
+                        *desc = ret;
         }
-}
 
-static void
-string_override(struct usb_gadget_strings **tab, u8 id, const char *s)
-{
-        while (*tab) {
-                string_override_one(*tab, id, s);
-                tab++;
-        }
+        return *desc;
 }
 
 static int composite_bind(struct usb_gadget *gadget)
@@ -1074,7 +1093,13 @@ static int composite_bind(struct usb_gadget *gadget)
         cdev->bufsiz = USB_BUFSIZ;
         cdev->driver = composite;
 
-        usb_gadget_set_selfpowered(gadget);
+        /*
+         * As per USB compliance update, a device that is actively drawing
+         * more than 100mA from USB must report itself as bus-powered in
+         * the GetStatus(DEVICE) call.
+         */
+        if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
+                usb_gadget_set_selfpowered(gadget);
 
         /* interface and string IDs start at zero via kzalloc.
          * we force endpoints to start unassigned; few controller
@@ -1094,26 +1119,41 @@ static int composite_bind(struct usb_gadget *gadget)
          * serial number), register function drivers, potentially update
          * power state and consumption, etc
          */
-        status = composite->bind(cdev);
+        status = composite_gadget_bind(cdev);
         if (status < 0)
                 goto fail;
 
         cdev->desc = *composite->dev;
         cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 
-        /* strings can't be assigned before bind() allocates the
-         * releavnt identifiers
-         */
-        if (cdev->desc.iManufacturer && iManufacturer)
-                string_override(composite->strings,
-                        cdev->desc.iManufacturer, iManufacturer);
-        if (cdev->desc.iProduct && iProduct)
-                string_override(composite->strings,
-                        cdev->desc.iProduct, iProduct);
-        if (cdev->desc.iSerialNumber && iSerialNumber)
-                string_override(composite->strings,
-                        cdev->desc.iSerialNumber, iSerialNumber);
+        /* stirng overrides */
+        if (iManufacturer || !cdev->desc.iManufacturer) {
+                if (!iManufacturer && !composite->iManufacturer &&
+                    !*composite_manufacturer)
+                        snprintf(composite_manufacturer,
+                                 sizeof composite_manufacturer,
+                                 "%s %s with %s",
+                                 init_utsname()->sysname,
+                                 init_utsname()->release,
+                                 gadget->name);
+
+                cdev->manufacturer_override =
+                        override_id(cdev, &cdev->desc.iManufacturer);
+        }
+
+        if (iProduct || (!cdev->desc.iProduct && composite->iProduct))
+                cdev->product_override =
+                        override_id(cdev, &cdev->desc.iProduct);
+
+        if (iSerialNumber)
+                cdev->serial_override =
+                        override_id(cdev, &cdev->desc.iSerialNumber);
+
+        /* has userspace failed to provide a serial number? */
+        if (composite->needs_serial && !cdev->desc.iSerialNumber)
+                WARNING(cdev, "userspace failed to provide iSerialNumber\n");
 
+        /* finish up */
         status = device_create_file(&gadget->dev, &dev_attr_suspended);
         if (status)
                 goto fail;
@@ -1177,7 +1217,6 @@ composite_resume(struct usb_gadget *gadget)
 static struct usb_gadget_driver composite_driver = {
         .speed          = USB_SPEED_HIGH,
 
-        .bind           = composite_bind,
         .unbind         = composite_unbind,
 
         .setup          = composite_setup,
@@ -1192,8 +1231,12 @@ static struct usb_gadget_driver composite_driver = {
 };
 
 /**
- * usb_composite_register() - register a composite driver
+ * usb_composite_probe() - register a composite driver
  * @driver: the driver to register
+ * @bind: the callback used to allocate resources that are shared across the
+ *      whole device, such as string IDs, and add its configurations using
+ *      @usb_add_config().  This may fail by returning a negative errno
+ *      value; it should return zero on successful initialization.
  * Context: single threaded during gadget setup
  *
  * This function is used to register drivers using the composite driver
@@ -1206,18 +1249,22 @@ static struct usb_gadget_driver composite_driver = {
  * while it was binding.  That would usually be done in order to wait for
  * some userspace participation.
  */
-int usb_composite_register(struct usb_composite_driver *driver)
+extern int usb_composite_probe(struct usb_composite_driver *driver,
+                               int (*bind)(struct usb_composite_dev *cdev))
 {
-        if (!driver || !driver->dev || !driver->bind || composite)
+        if (!driver || !driver->dev || !bind || composite)
                 return -EINVAL;
 
+        if (!driver->iProduct)
+                driver->iProduct = driver->name;
         if (!driver->name)
                 driver->name = "composite";
         composite_driver.function =  (char *) driver->name;
         composite_driver.driver.name = driver->name;
         composite = driver;
+        composite_gadget_bind = bind;
 
-        return usb_gadget_register_driver(&composite_driver);
+        return usb_gadget_probe_driver(&composite_driver, composite_bind);
 }
 
 /**