freebsd-dev/sys/dev/usb/serial/usb_serial.h
Hans Petter Selasky 0eb8d46232 Improve USB polling mode by not locking any mutexes, asserting any
mutexes or using any callouts when active.

Trying to lock a mutex when KDB is active or the scheduler is stopped
can result in infinite wait loops. The same goes for calling callout
related functions which in turn lock mutexes.

If the USB controller at which a USB keyboard is connected is idle
when KDB is entered, polling the USB keyboard via USB will always
succeed. Else polling may fail depending on which state the USB
subsystem and USB interrupt handler is in. This is unavoidable unless
KDB can wait for USB interrupt threads to complete before stalling the
CPU(s).

Tested by:	Bruce Evans <bde@freebsd.org>
MFC after:	4 weeks
2016-09-14 12:07:34 +00:00

222 lines
8.5 KiB
C

/* $NetBSD: ucomvar.h,v 1.9 2001/01/23 21:56:17 augustss Exp $ */
/* $FreeBSD$ */
/*-
* Copyright (c) 2001-2002, Shunsuke Akiyama <akiyama@jp.FreeBSD.org>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Lennart Augustsson (lennart@augustsson.net) at
* Carlstedt Research & Technology.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _USB_SERIAL_H_
#define _USB_SERIAL_H_
#include <sys/tty.h>
#include <sys/serial.h>
#include <sys/fcntl.h>
#include <sys/sysctl.h>
#include <sys/timepps.h>
/* Module interface related macros */
#define UCOM_MODVER 1
#define UCOM_MINVER 1
#define UCOM_PREFVER UCOM_MODVER
#define UCOM_MAXVER 1
#define UCOM_JITTERBUF_SIZE 128 /* bytes */
struct usb_device;
struct ucom_softc;
struct usb_device_request;
struct thread;
/*
* NOTE: There is no guarantee that "ucom_cfg_close()" will
* be called after "ucom_cfg_open()" if the device is detached
* while it is open!
*/
struct ucom_callback {
void (*ucom_cfg_get_status) (struct ucom_softc *, uint8_t *plsr, uint8_t *pmsr);
void (*ucom_cfg_set_dtr) (struct ucom_softc *, uint8_t);
void (*ucom_cfg_set_rts) (struct ucom_softc *, uint8_t);
void (*ucom_cfg_set_break) (struct ucom_softc *, uint8_t);
void (*ucom_cfg_set_ring) (struct ucom_softc *, uint8_t);
void (*ucom_cfg_param) (struct ucom_softc *, struct termios *);
void (*ucom_cfg_open) (struct ucom_softc *);
void (*ucom_cfg_close) (struct ucom_softc *);
int (*ucom_pre_open) (struct ucom_softc *);
int (*ucom_pre_param) (struct ucom_softc *, struct termios *);
int (*ucom_ioctl) (struct ucom_softc *, uint32_t, caddr_t, int, struct thread *);
void (*ucom_start_read) (struct ucom_softc *);
void (*ucom_stop_read) (struct ucom_softc *);
void (*ucom_start_write) (struct ucom_softc *);
void (*ucom_stop_write) (struct ucom_softc *);
void (*ucom_tty_name) (struct ucom_softc *, char *pbuf, uint16_t buflen, uint16_t unit, uint16_t subunit);
void (*ucom_poll) (struct ucom_softc *);
void (*ucom_free) (struct ucom_softc *);
};
/* Line status register */
#define ULSR_RCV_FIFO 0x80
#define ULSR_TSRE 0x40 /* Transmitter empty: byte sent */
#define ULSR_TXRDY 0x20 /* Transmitter buffer empty */
#define ULSR_BI 0x10 /* Break detected */
#define ULSR_FE 0x08 /* Framing error: bad stop bit */
#define ULSR_PE 0x04 /* Parity error */
#define ULSR_OE 0x02 /* Overrun, lost incoming byte */
#define ULSR_RXRDY 0x01 /* Byte ready in Receive Buffer */
#define ULSR_RCV_MASK 0x1f /* Mask for incoming data or error */
struct ucom_cfg_task {
struct usb_proc_msg hdr;
struct ucom_softc *sc;
};
struct ucom_param_task {
struct usb_proc_msg hdr;
struct ucom_softc *sc;
struct termios termios_copy;
};
struct ucom_super_softc {
struct usb_process sc_tq;
int sc_unit;
int sc_subunits;
int sc_refs;
int sc_flag; /* see UCOM_FLAG_XXX */
struct sysctl_oid *sc_sysctl_ttyname;
struct sysctl_oid *sc_sysctl_ttyports;
char sc_ttyname[16];
};
struct ucom_softc {
/*
* NOTE: To avoid losing level change information we use two
* tasks instead of one for all commands.
*
* Level changes are transitions like:
*
* ON->OFF
* OFF->ON
* OPEN->CLOSE
* CLOSE->OPEN
*/
struct ucom_cfg_task sc_start_task[2];
struct ucom_cfg_task sc_open_task[2];
struct ucom_cfg_task sc_close_task[2];
struct ucom_cfg_task sc_line_state_task[2];
struct ucom_cfg_task sc_status_task[2];
struct ucom_param_task sc_param_task[2];
/* pulse capturing support, PPS */
struct pps_state sc_pps;
/* Used to set "UCOM_FLAG_GP_DATA" flag: */
struct usb_proc_msg *sc_last_start_xfer;
const struct ucom_callback *sc_callback;
struct ucom_super_softc *sc_super;
struct tty *sc_tty;
struct mtx *sc_mtx;
void *sc_parent;
int sc_subunit;
uint16_t sc_jitterbuf_in;
uint16_t sc_jitterbuf_out;
uint16_t sc_portno;
uint16_t sc_flag;
#define UCOM_FLAG_RTS_IFLOW 0x01 /* use RTS input flow control */
#define UCOM_FLAG_GONE 0x02 /* the device is gone */
#define UCOM_FLAG_ATTACHED 0x04 /* set if attached */
#define UCOM_FLAG_GP_DATA 0x08 /* set if get and put data is possible */
#define UCOM_FLAG_LL_READY 0x20 /* set if low layer is ready */
#define UCOM_FLAG_HL_READY 0x40 /* set if high layer is ready */
#define UCOM_FLAG_CONSOLE 0x80 /* set if device is a console */
#define UCOM_FLAG_WAIT_REFS 0x0100 /* set if we must wait for refs */
#define UCOM_FLAG_FREE_UNIT 0x0200 /* set if we must free the unit */
#define UCOM_FLAG_INWAKEUP 0x0400 /* set if we are in the tsw_inwakeup callback */
uint8_t sc_lsr;
uint8_t sc_msr;
uint8_t sc_mcr;
/* programmed line state bits */
uint8_t sc_pls_set; /* set bits */
uint8_t sc_pls_clr; /* cleared bits */
uint8_t sc_pls_curr; /* last state */
#define UCOM_LS_DTR 0x01
#define UCOM_LS_RTS 0x02
#define UCOM_LS_BREAK 0x04
#define UCOM_LS_RING 0x08
uint8_t sc_jitterbuf[UCOM_JITTERBUF_SIZE];
};
#define UCOM_MTX_ASSERT(sc, what) USB_MTX_ASSERT((sc)->sc_mtx, what)
#define UCOM_MTX_LOCK(sc) USB_MTX_LOCK((sc)->sc_mtx)
#define UCOM_MTX_UNLOCK(sc) USB_MTX_UNLOCK((sc)->sc_mtx)
#define UCOM_UNLOAD_DRAIN(x) \
SYSUNINIT(var, SI_SUB_KLD - 2, SI_ORDER_ANY, ucom_drain_all, 0)
#define ucom_cfg_do_request(udev,com,req,ptr,flags,timo) \
usbd_do_request_proc(udev,&(com)->sc_super->sc_tq,req,ptr,flags,NULL,timo)
int ucom_attach(struct ucom_super_softc *,
struct ucom_softc *, int, void *,
const struct ucom_callback *callback, struct mtx *);
void ucom_detach(struct ucom_super_softc *, struct ucom_softc *);
void ucom_set_pnpinfo_usb(struct ucom_super_softc *, device_t);
void ucom_status_change(struct ucom_softc *);
uint8_t ucom_get_data(struct ucom_softc *, struct usb_page_cache *,
uint32_t, uint32_t, uint32_t *);
void ucom_put_data(struct ucom_softc *, struct usb_page_cache *,
uint32_t, uint32_t);
uint8_t ucom_cfg_is_gone(struct ucom_softc *);
void ucom_drain(struct ucom_super_softc *);
void ucom_drain_all(void *);
void ucom_ref(struct ucom_super_softc *);
int ucom_unref(struct ucom_super_softc *);
#endif /* _USB_SERIAL_H_ */