Commit 48cf0b5a authored by Yu Chen's avatar Yu Chen Committed by Ionela Voinescu
Browse files

usb: gadget: Add configfs attribuite for controling match_existing_only

Currently the "match_existing_only" of usb_gadget_driver in configfs is
set to one which is not flexible.
Dwc3 udc will be removed when usb core switch to host mode. This causes
failure of writing name of dwc3 udc to configfs's UDC attribuite.
To fix this we need to add a way to change the config of
There are systems like Android do not support udev, so adding
"match_existing_only" attribute to allow configuration by user is cost little.
This patch adds a configfs attribuite for controling match_existing_only
which allow user to config "match_existing_only".

Cc: Andy Shevchenko <>
Cc: Felipe Balbi <>
Cc: Greg Kroah-Hartman <>
Cc: John Stultz <>
Cc: Binghui Wang <>
Signed-off-by: default avatarYu Chen <>
Signed-off-by: default avatarJohn Stultz <>
Change-Id: I49862a4de4e56b235278cddf7a5ec6e30c5f2ec4
parent 90406541
......@@ -338,6 +338,36 @@ err:
return -EINVAL;
static ssize_t gadget_driver_match_existing_only_store(struct config_item *item,
const char *page, size_t len)
struct gadget_info *gi = to_gadget_info(item);
struct usb_gadget_driver *gadget_driver = &(gi->composite.gadget_driver);
bool match_existing_only;
int ret;
ret = kstrtobool(page, &match_existing_only);
if (ret)
return ret;
if (match_existing_only)
gadget_driver->match_existing_only = 1;
gadget_driver->match_existing_only = 0;
return len;
static ssize_t gadget_driver_match_existing_only_show(struct config_item *item,
char *page)
struct gadget_info *gi = to_gadget_info(item);
struct usb_gadget_driver *gadget_driver = &(gi->composite.gadget_driver);
bool match_existing_only = !!gadget_driver->match_existing_only;
return sprintf(page, "%s\n", match_existing_only ? "true" : "false");
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceClass);
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceSubClass);
CONFIGFS_ATTR(gadget_dev_desc_, bDeviceProtocol);
......@@ -348,6 +378,7 @@ CONFIGFS_ATTR(gadget_dev_desc_, bcdDevice);
CONFIGFS_ATTR(gadget_dev_desc_, bcdUSB);
CONFIGFS_ATTR(gadget_dev_desc_, UDC);
CONFIGFS_ATTR(gadget_dev_desc_, max_speed);
CONFIGFS_ATTR(gadget_, driver_match_existing_only);
static struct configfs_attribute *gadget_root_attrs[] = {
......@@ -360,6 +391,7 @@ static struct configfs_attribute *gadget_root_attrs[] = {
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