@@ -3,6 +3,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/device.h>
+#include <linux/idr.h>
#include <linux/kstrtox.h>
#include <linux/nls.h>
#include <linux/usb/composite.h>
@@ -11,6 +12,16 @@
#include "u_f.h"
#include "u_os_desc.h"
+static DEFINE_IDA(driver_id_numbers);
+
+/*
+ * Driver name has the form of "configfs-gadget.%d", where %d
+ * is id allocated by ida_alloc(). The max value returns by
+ * ida_alloc() is INT_MAX, in 64-bit system, it is about nine
+ * quintillion: 19 digits in decimal. Set the max length to 35.
+ */
+#define DRIVER_NAME_LENGTH_MAX 35
+
int check_user_usb_string(const char *name,
struct usb_gadget_strings *stringtab_dev)
{
@@ -52,6 +63,9 @@ struct gadget_info {
char qw_sign[OS_STRING_QW_SIGN_LEN];
spinlock_t spinlock;
bool unbind;
+
+ /* Make driver names unique */
+ int driver_id_number;
};
static inline struct gadget_info *to_gadget_info(struct config_item *item)
@@ -1582,6 +1596,8 @@ static struct config_group *gadgets_make(
const char *name)
{
struct gadget_info *gi;
+ char *driver_name;
+ int ret;
gi = kzalloc(sizeof(*gi), GFP_KERNEL);
if (!gi)
@@ -1623,6 +1639,21 @@ static struct config_group *gadgets_make(
gi->composite.gadget_driver = configfs_driver_template;
+ ret = ida_alloc(&driver_id_numbers, GFP_KERNEL);
+ if (ret < 0)
+ goto err;
+ gi->driver_id_number = ret;
+
+ driver_name = kmalloc(DRIVER_NAME_LENGTH_MAX, GFP_KERNEL);
+ if (!driver_name)
+ goto out_free_driver_id_number;
+
+ ret = scnprintf(driver_name, DRIVER_NAME_LENGTH_MAX,
+ "configfs-gadget.%d", gi->driver_id_number);
+ if (ret < 0)
+ goto out_free_driver_name;
+
+ gi->composite.gadget_driver.driver.name = driver_name;
gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
gi->composite.name = gi->composite.gadget_driver.function;
@@ -1630,6 +1661,11 @@ static struct config_group *gadgets_make(
goto err;
return &gi->group;
+
+out_free_driver_name:
+ kfree(driver_name);
+out_free_driver_id_number:
+ ida_free(&driver_id_numbers, gi->driver_id_number);
err:
kfree(gi);
return ERR_PTR(-ENOMEM);
@@ -1637,6 +1673,12 @@ static struct config_group *gadgets_make(
static void gadgets_drop(struct config_group *group, struct config_item *item)
{
+ struct gadget_info *gi = to_gadget_info(item);
+
+ mutex_lock(&gi->lock);
+ kfree(gi->composite.gadget_driver.driver.name);
+ ida_free(&driver_id_numbers, gi->driver_id_number);
+ mutex_unlock(&gi->lock);
config_item_put(item);
}
It is unable to use configfs to attach more than one gadget. When attaching the second gadget, it always fails and the kernel message prints out: Error: Driver 'configfs-gadget' is already registered, aborting... UDC core: g1: driver registration failed: -16 This commit fixes the problem by a ".N" suffix added to each configfs_gadget's driver name (where N is a unique ID number), thus making the names distinct. Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets") Signed-off-by: Chanh Nguyen <chanh@os.amperecomputing.com> --- drivers/usb/gadget/configfs.c | 42 +++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+)