On Tue, Dec 13, 2022 at 05:03:54PM -0500, Frank Li wrote:
> From: Rondreis <linhaoguo86@xxxxxxxxx>
>
> When use configfs to attach more than one gadget.
>
> Error: Driver 'configfs-gadget' is already registered, aborting...
>
> UDC core: g1: driver registration failed: -16
>
> The problem is that when creating multiple gadgets with configfs and
> binding them to different UDCs, the UDC drivers have the same name
> "configfs-gadget". Because of the addition of the "gadget" bus, naming
> conflicts will occur when more than one UDC drivers registered to the
> bus.
>
> It's not an isolated case, this patch refers to the commit f2d8c2606825
> ("usb: gadget: Fix non-unique driver names in raw-gadget driver").
> Each configfs-gadget driver will be assigned a unique name
> "configfs-gadget.N", with a different value of N for each driver
> instance.
>
> Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets")
>
> Signed-off-by: Rondreis <linhaoguo86@xxxxxxxxx>
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> ---
>
> This patch is based on https://lore.kernel.org/lkml/20220907112210.11949-1-linhaoguo86@xxxxxxxxx/
> fixed the all greg's comments.
>
> I met the same issue. Look likes Rodrieis have not continue to work this
> patch since Sep, 2022.
>
> I don't know full name of Rondreis.
>
> drivers/usb/gadget/configfs.c | 30 ++++++++++++++++++++++++++----
> 1 file changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
> index 3a6b4926193e..785be6aea720 100644
> --- a/drivers/usb/gadget/configfs.c
> +++ b/drivers/usb/gadget/configfs.c
> @@ -4,12 +4,17 @@
> #include <linux/slab.h>
> #include <linux/device.h>
> #include <linux/nls.h>
> +#include <linux/idr.h>
> #include <linux/usb/composite.h>
> #include <linux/usb/gadget_configfs.h>
> #include "configfs.h"
> #include "u_f.h"
> #include "u_os_desc.h"
>
> +#define DRIVER_NAME "configfs-gadget"
> +
> +static DEFINE_IDA(driver_id_numbers);
> +
> int check_user_usb_string(const char *name,
> struct usb_gadget_strings *stringtab_dev)
> {
> @@ -46,6 +51,7 @@ struct gadget_info {
>
> struct usb_composite_driver composite;
> struct usb_composite_dev cdev;
> + int driver_id_number;
> bool use_os_desc;
> char b_vendor_code;
> char qw_sign[OS_STRING_QW_SIGN_LEN];
> @@ -392,6 +398,8 @@ static void gadget_info_attr_release(struct config_item *item)
> WARN_ON(!list_empty(&gi->string_list));
> WARN_ON(!list_empty(&gi->available_func));
> kfree(gi->composite.gadget_driver.function);
> + kfree(gi->composite.gadget_driver.driver.name);
> + ida_free(&driver_id_numbers, gi->driver_id_number);
> kfree(gi);
> }
>
> @@ -1571,7 +1579,6 @@ static const struct usb_gadget_driver configfs_driver_template = {
> .max_speed = USB_SPEED_SUPER_PLUS,
> .driver = {
> .owner = THIS_MODULE,
> - .name = "configfs-gadget",
> },
> .match_existing_only = 1,
> };
> @@ -1581,6 +1588,7 @@ static struct config_group *gadgets_make(
> const char *name)
> {
> struct gadget_info *gi;
> + int ret = 0;
>
> gi = kzalloc(sizeof(*gi), GFP_KERNEL);
> if (!gi)
> @@ -1622,16 +1630,30 @@ 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;
> +
> + gi->composite.gadget_driver.driver.name =
> + kasprintf(GFP_KERNEL, DRIVER_NAME ".%d", gi->driver_id_number);
Here you forgot to put:
if (!gi->composite.gadget_driver.driver.name) {
ret = -ENOMEM;
goto err_func;
}
Or if you prefer, combine this test with the one below.
Alan Stern
> +
> gi->composite.gadget_driver.function = kstrdup(name, GFP_KERNEL);
> gi->composite.name = gi->composite.gadget_driver.function;
>
> - if (!gi->composite.gadget_driver.function)
> - goto err;
> + if (!gi->composite.gadget_driver.function) {
> + ret = -ENOMEM;
> + goto err_func;
> + }
>
> return &gi->group;
> +
> +err_func:
> + kfree(gi->composite.gadget_driver.driver.name);
> + ida_free(&driver_id_numbers, gi->driver_id_number);
> err:
> kfree(gi);
> - return ERR_PTR(-ENOMEM);
> + return ERR_PTR(ret);
> }
>
> static void gadgets_drop(struct config_group *group, struct config_item *item)
> --
> 2.34.1
>
