linux_dsm_epyc7002/drivers/usb/class/cdc-acm.h
David Brownell e5fbab51b4 usb: cdc-acm: drain writes on close
Add a mechanism to let the write queue drain naturally before
closing the TTY, rather than always losing that data.  There
is a timeout, so it can't wait too long.

Provide missing locking inside acm_wb_is_avail(); it matters
more now.  Note, this presumes an earlier patch was applied,
removing a call to this routine where the lock was held.

Slightly improved diagnostics on write URB completion, so we
can tell when a write URB gets killed and, if so, how much
data it wrote first ... and so that I/O path is normally
silent (and can't much change timings).

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-13 17:32:57 -07:00

137 lines
3.6 KiB
C

/*
*
* Includes for cdc-acm.c
*
* Mainly take from usbnet's cdc-ether part
*
*/
/*
* CMSPAR, some architectures can't have space and mark parity.
*/
#ifndef CMSPAR
#define CMSPAR 0
#endif
/*
* Major and minor numbers.
*/
#define ACM_TTY_MAJOR 166
#define ACM_TTY_MINORS 32
/*
* Requests.
*/
#define USB_RT_ACM (USB_TYPE_CLASS | USB_RECIP_INTERFACE)
/*
* Output control lines.
*/
#define ACM_CTRL_DTR 0x01
#define ACM_CTRL_RTS 0x02
/*
* Input control lines and line errors.
*/
#define ACM_CTRL_DCD 0x01
#define ACM_CTRL_DSR 0x02
#define ACM_CTRL_BRK 0x04
#define ACM_CTRL_RI 0x08
#define ACM_CTRL_FRAMING 0x10
#define ACM_CTRL_PARITY 0x20
#define ACM_CTRL_OVERRUN 0x40
/*
* Internal driver structures.
*/
/*
* The only reason to have several buffers is to accomodate assumptions
* in line disciplines. They ask for empty space amount, receive our URB size,
* and proceed to issue several 1-character writes, assuming they will fit.
* The very first write takes a complete URB. Fortunately, this only happens
* when processing onlcr, so we only need 2 buffers. These values must be
* powers of 2.
*/
#define ACM_NW 16
#define ACM_NR 16
struct acm_wb {
unsigned char *buf;
dma_addr_t dmah;
int len;
int use;
struct urb *urb;
struct acm *instance;
};
struct acm_rb {
struct list_head list;
int size;
unsigned char *base;
dma_addr_t dma;
};
struct acm_ru {
struct list_head list;
struct acm_rb *buffer;
struct urb *urb;
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 */
struct tty_struct *tty; /* the corresponding tty */
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];
struct acm_ru ru[ACM_NR];
struct acm_rb rb[ACM_NR];
int rx_buflimit;
int rx_endpoint;
spinlock_t read_lock;
struct list_head spare_read_urbs;
struct list_head spare_read_bufs;
struct list_head filled_read_bufs;
int write_used; /* number of non-empty write buffers */
int processing;
int transmitting;
spinlock_t write_lock;
struct mutex mutex;
struct usb_cdc_line_coding line; /* bits, stop, parity */
struct work_struct work; /* work queue entry for line discipline waking up */
struct work_struct waker;
wait_queue_head_t drain_wait; /* close processing */
struct tasklet_struct urb_task; /* rx processing */
spinlock_t throttle_lock; /* synchronize throtteling and read callback */
unsigned int ctrlin; /* input control lines (DCD, DSR, RI, break, overruns) */
unsigned int ctrlout; /* output control lines (DTR, RTS) */
unsigned int writesize; /* max packet size for the output bulk endpoint */
unsigned int readsize,ctrlsize; /* buffer sizes for freeing */
unsigned int used; /* someone has this acm's device open */
unsigned int minor; /* acm minor number */
unsigned char throttle; /* throttled by tty layer */
unsigned char clocal; /* termios CLOCAL */
unsigned int ctrl_caps; /* control capabilities from the class specific header */
unsigned int susp_count; /* number of suspended interfaces */
struct acm_wb *delayed_wb; /* write queued for a device about to be woken */
};
#define CDC_DATA_INTERFACE_TYPE 0x0a
/* constants describing various quirks and errors */
#define NO_UNION_NORMAL 1
#define SINGLE_RX_URB 2