drivers/usb/gadget/configfs.c

File Facts

System

Linux kernel

Corpus path

drivers/usb/gadget/configfs.c

Extension

.c

Size

52601 bytes

Lines

2109

Domain

Driver Families

Bucket

drivers/usb

Inferred role

Driver Families: exported/initcall integration point

Status

integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

• Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
• Exports symbols or registers init work; inspect boot/module ordering and who consumes the exported contract.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Allocates kernel memory; connect allocation flags and lifetime to context constraints.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/configfs.h
• linux/module.h
• linux/slab.h
• linux/device.h
• linux/kstrtox.h
• linux/nls.h
• linux/usb/composite.h
• linux/usb/func_utils.h
• linux/usb/gadget_configfs.h
• linux/usb/webusb.h
• configfs.h
• u_os_desc.h

Detected Declarations

• struct gadget_info
• struct config_usb_cfg
• struct gadget_language
• struct gadget_config_name
• function check_user_usb_string
• function usb_string_copy
• function is_valid_bcd
• function gadget_dev_desc_bcdDevice_store
• function gadget_dev_desc_bcdUSB_store
• function gadget_dev_desc_UDC_show
• function unregister_gadget
• function gadget_dev_desc_UDC_store
• function gadget_dev_desc_max_speed_show
• function gadget_dev_desc_max_speed_store
• function gadget_info_attr_release
• function gadget_config_attr_release
• function config_usb_cfg_link
• function list_for_each_entry
• function list_for_each_entry
• function config_usb_cfg_unlink
• function list_for_each_entry
• function gadget_config_desc_MaxPower_show
• function gadget_config_desc_MaxPower_store
• function gadget_config_desc_bmAttributes_show
• function gadget_config_desc_bmAttributes_store
• function composite_init_dev
• function function_drop
• function gadget_config_name_attr_release
• function config_desc_drop
• function gadget_language_attr_release
• function gadget_string_id_show
• function gadget_string_s_show
• function gadget_string_s_store
• function gadget_string_release
• function gadget_language_string_drop
• function gadget_language_drop
• function webusb_use_show
• function webusb_use_store
• function webusb_bcdVersion_show
• function webusb_bcdVersion_store
• function webusb_bVendorCode_show
• function webusb_bVendorCode_store
• function webusb_landingPage_show
• function webusb_landingPage_store
• function os_desc_use_show
• function os_desc_use_store
• function os_desc_b_vendor_code_show
• function os_desc_b_vendor_code_store

Annotated Snippet

module_init(gadget_cfs_init);

static void __exit gadget_cfs_exit(void)
{
	configfs_unregister_subsystem(&gadget_subsys);
}
module_exit(gadget_cfs_exit);

Annotation

• Immediate include surface: `linux/configfs.h`, `linux/module.h`, `linux/slab.h`, `linux/device.h`, `linux/kstrtox.h`, `linux/nls.h`, `linux/usb/composite.h`, `linux/usb/func_utils.h`.
• Detected declarations: `struct gadget_info`, `struct config_usb_cfg`, `struct gadget_language`, `struct gadget_config_name`, `function check_user_usb_string`, `function usb_string_copy`, `function is_valid_bcd`, `function gadget_dev_desc_bcdDevice_store`, `function gadget_dev_desc_bcdUSB_store`, `function gadget_dev_desc_UDC_show`.
• Atlas domain: Driver Families / drivers/usb.
• Implementation status: integration implementation candidate.
• Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

• This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
• Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
• Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.