[usb] Expose usb_find_driver()

Signed-off-by: Michael Brown <mcb30@ipxe.org>

diff --git a/src/drivers/bus/usb.c b/src/drivers/bus/usb.c
index 2019e3341dfbf97ae0aae9e1a3f7e70debdbe63e..2520922e096889dc8d15008a5ef8189986a4d0d6 100644 (file)
--- a/src/drivers/bus/usb.c
+++ b/src/drivers/bus/usb.c
@@ -972,22 +972,40 @@ static int usb_function ( struct usb_function *func,
 }
 
 /**
- * Check for a USB device ID match
+ * Find USB device driver
  *
- * @v func             USB function
- * @v id               Device ID
- * @ret matches                Device ID matches
- */
-static int
-usb_device_id_matches ( struct usb_function *func, struct usb_device_id *id ) {
-
-       return ( ( ( id->vendor == func->dev.desc.vendor ) ||
-                  ( id->vendor == USB_ANY_ID ) ) &&
-                ( ( id->product == func->dev.desc.device ) ||
-                  ( id->product == USB_ANY_ID ) ) &&
-                ( id->class.class == func->class.class ) &&
-                ( id->class.subclass == func->class.subclass ) &&
-                ( id->class.protocol == func->class.protocol ) );
+ * @v vendor           Vendor ID
+ * @v product          Product ID
+ * @v class            Class
+ * @ret id             USB device ID, or NULL
+ * @ret driver         USB device driver, or NULL
+ */
+struct usb_driver * usb_find_driver ( unsigned int vendor, unsigned int product,
+                                     struct usb_class *class,
+                                     struct usb_device_id **id ) {
+       struct usb_driver *driver;
+       unsigned int i;
+
+       /* Look for a matching driver */
+       for_each_table_entry ( driver, USB_DRIVERS ) {
+               for ( i = 0 ; i < driver->id_count ; i++ ) {
+
+                       /* Check for a matching ID */
+                       *id = &driver->ids[i];
+                       if ( ( ( (*id)->vendor == vendor ) ||
+                              ( (*id)->vendor == USB_ANY_ID ) ) &&
+                            ( ( (*id)->product == product ) ||
+                              ( (*id)->product == USB_ANY_ID ) ) &&
+                            ( (*id)->class.class == class->class ) &&
+                            ( (*id)->class.subclass == class->subclass ) &&
+                            ( (*id)->class.protocol == class->protocol ) )
+                               return driver;
+               }
+       }
+
+       /* Not found */
+       *id = NULL;
+       return NULL;
 }
 
 /**
@@ -1002,39 +1020,30 @@ static int usb_probe ( struct usb_function *func,
        struct usb_device *usb = func->usb;
        struct usb_driver *driver;
        struct usb_device_id *id;
-       unsigned int i;
        int rc;
 
-       /* Look for a matching driver */
-       for_each_table_entry ( driver, USB_DRIVERS ) {
-               for ( i = 0 ; i < driver->id_count ; i++ ) {
-
-                       /* Check for a matching ID */
-                       id = &driver->ids[i];
-                       if ( ! usb_device_id_matches ( func, id ) )
-                               continue;
-
-                       /* Probe driver */
-                       if ( ( rc = driver->probe ( func, config ) ) != 0 ) {
-                               DBGC ( usb, "USB %s failed to probe driver %s: "
-                                      "%s\n", func->name, id->name,
-                                      strerror ( rc ) );
-                               /* Continue trying other drivers */
-                               continue;
-                       }
+       /* Identify driver */
+       driver = usb_find_driver ( func->dev.desc.vendor, func->dev.desc.device,
+                                  &func->class, &id );
+       if ( ! driver ) {
+               DBGC ( usb, "USB %s %04x:%04x class %d:%d:%d has no driver\n",
+                      func->name, func->dev.desc.vendor, func->dev.desc.device,
+                      func->class.class, func->class.subclass,
+                      func->class.protocol );
+               return -ENOENT;
+       }
 
-                       /* Record driver */
-                       func->driver = driver;
-                       func->dev.driver_name = id->name;
-                       return 0;
-               }
+       /* Probe driver */
+       if ( ( rc = driver->probe ( func, config ) ) != 0 ) {
+               DBGC ( usb, "USB %s failed to probe driver %s: %s\n",
+                      func->name, id->name, strerror ( rc ) );
+               return rc;
        }
 
-       /* No driver found */
-       DBGC ( usb, "USB %s %04x:%04x class %d:%d:%d has no driver\n",
-              func->name, func->dev.desc.vendor, func->dev.desc.device,
-              func->class.class, func->class.subclass, func->class.protocol );
-       return -ENOENT;
+       /* Record driver */
+       func->driver = driver;
+       func->dev.driver_name = id->name;
+       return 0;
 }
 
 /**

diff --git a/src/include/ipxe/usb.h b/src/include/ipxe/usb.h
index ab060b8f48b4908add3ea094201a24962562379b..f7c0b96e56ff08e31c289c5896565a67de5adc8a 100644 (file)
--- a/src/include/ipxe/usb.h
+++ b/src/include/ipxe/usb.h
@@ -1316,4 +1316,9 @@ struct usb_driver {
 /** Declare a USB driver */
 #define __usb_driver __table_entry ( USB_DRIVERS, 01 )
 
+extern struct usb_driver * usb_find_driver ( unsigned int vendor,
+                                            unsigned int product,
+                                            struct usb_class *class,
+                                            struct usb_device_id **id );
+
 #endif /* _IPXE_USB_H */