drivers/usb/class/cdc-acm.h
Source file repositories/reference/linux-study-clean/drivers/usb/class/cdc-acm.h
File Facts
- System
- Linux kernel
- Corpus path
drivers/usb/class/cdc-acm.h- Extension
.h- Size
- 3840 bytes
- Lines
- 120
- Domain
- Driver Families
- Bucket
- drivers/usb
- Inferred role
- Driver Families: implementation source
- Status
- source 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.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
struct acm_wbstruct acm_rbstruct acm
Annotated Snippet
struct acm_wb {
u8 *buf;
dma_addr_t dmah;
unsigned int len;
struct urb *urb;
struct acm *instance;
bool use;
};
struct acm_rb {
int size;
unsigned char *base;
dma_addr_t dma;
int index;
struct acm *instance;
};
struct acm {
struct usb_device *dev; /* the corresponding usb device */
struct usb_interface *control; /* control interface */
struct usb_interface *data; /* data interface */
unsigned in, out; /* i/o pipes */
struct tty_port port; /* our tty port data */
struct urb *ctrlurb; /* urbs */
u8 *ctrl_buffer; /* buffers of urbs */
dma_addr_t ctrl_dma; /* dma handles of buffers */
u8 *country_codes; /* country codes from device */
unsigned int country_code_size; /* size of this buffer */
unsigned int country_rel_date; /* release date of version */
struct acm_wb wb[ACM_NW];
unsigned long read_urbs_free;
struct urb *read_urbs[ACM_NR];
struct acm_rb read_buffers[ACM_NR];
int rx_buflimit;
spinlock_t read_lock;
u8 *notification_buffer; /* to reassemble fragmented notifications */
unsigned int nb_index;
unsigned int nb_size;
int transmitting;
spinlock_t write_lock;
struct mutex mutex;
bool disconnected;
unsigned long flags;
# define EVENT_TTY_WAKEUP 0
# define EVENT_RX_STALL 1
# define ACM_THROTTLED 2
# define ACM_ERROR_DELAY 3
unsigned long urbs_in_error_delay; /* these need to be restarted after a delay */
struct usb_cdc_line_coding line; /* bits, stop, parity */
struct delayed_work dwork; /* work queue entry for various purposes */
unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */
unsigned int ctrlout; /* output control lines (DTR, RTS) */
struct async_icount iocount; /* counters for control line changes */
struct async_icount oldcount; /* for comparison of counter */
wait_queue_head_t wioctl; /* for ioctl */
unsigned int writesize; /* max packet size for the output bulk endpoint */
unsigned int readsize,ctrlsize; /* buffer sizes for freeing */
unsigned int minor; /* acm minor number */
unsigned char clocal; /* termios CLOCAL */
unsigned int ctrl_caps; /* control capabilities from the class specific header */
unsigned int susp_count; /* number of suspended interfaces */
unsigned int combined_interfaces:1; /* control and data collapsed */
u8 bInterval;
struct usb_anchor delayed; /* writes queued for a device about to be woken */
unsigned long quirks;
};
/* constants describing various quirks and errors */
#define NO_UNION_NORMAL BIT(0)
#define SINGLE_RX_URB BIT(1)
#define NO_CAP_LINE BIT(2)
#define IGNORE_DEVICE BIT(3)
#define QUIRK_CONTROL_LINE_STATE BIT(4)
#define CLEAR_HALT_CONDITIONS BIT(5)
#define SEND_ZERO_PACKET BIT(6)
#define DISABLE_ECHO BIT(7)
#define MISSING_CAP_BRK BIT(8)
#define NO_UNION_12 BIT(9)
#define VENDOR_CLASS_DATA_IFACE BIT(10) /* data interface uses vendor-specific class */
#define ALWAYS_POLL_CTRL BIT(11) /* keep ctrl URB active even without an open TTY */
Annotation
- Detected declarations: `struct acm_wb`, `struct acm_rb`, `struct acm`.
- Atlas domain: Driver Families / drivers/usb.
- Implementation status: source implementation candidate.
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.