freebsd-skq/sys/dev/iicbus/iicbus.h
jhb 3b547d7c3f Add locking to the core iicbus(4) drivers:
- Add an sx lock to the iic(4) driver to serialize open(), close(), read(),
  and write and to protect sc_addr and sc_count in the softc.
- Use cdev->si_drv1 instead of using the minor number of the cdev to
  lookup the softc via newbus in iic(4).
- Store the device_t in the softc to avoid a similar detour via minor
  numbers in iic(4).
- Only add at most one instance of iic(4) and iicsmb(4) to each iicbus(4)
  instance, and do it in the child driver.
- Add a mutex to the iicbus(4) softc to synchronize the request/release bus
  stuff.
- Use __BUS_ACCESSOR() for IICBUS_ACCESSOR() instead of rolling our own.
- Add a mutex to the iicsmb(4) softc to protect softc state updated in the
  interrupt handler.
- Remove Giant from all the smbus methods in iicsmb(4) now that all the
  iicbus(4) backend is locked.
2008-08-04 21:03:06 +00:00

71 lines
2.3 KiB
C

/*-
* Copyright (c) 1998 Nicolas Souchu
* 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.
*
* $FreeBSD$
*
*/
#ifndef __IICBUS_H
#define __IICBUS_H
#include <sys/_lock.h>
#include <sys/_mutex.h>
#define IICBUS_IVAR(d) (struct iicbus_ivar *) device_get_ivars(d)
#define IICBUS_SOFTC(d) (struct iicbus_softc *) device_get_softc(d)
struct iicbus_softc
{
device_t dev; /* Myself */
device_t owner; /* iicbus owner device structure */
u_char started; /* address of the 'started' slave
* 0 if no start condition succeeded */
struct mtx lock;
};
struct iicbus_ivar
{
uint32_t addr;
};
enum {
IICBUS_IVAR_ADDR /* Address or base address */
};
#define IICBUS_ACCESSOR(A, B, T) \
__BUS_ACCESSOR(iicbus, A, IICBUS, B, T)
IICBUS_ACCESSOR(addr, ADDR, uint32_t)
#define IICBUS_LOCK(sc) mtx_lock(&(sc)->lock)
#define IICBUS_UNLOCK(sc) mtx_unlock(&(sc)->lock)
#define IICBUS_ASSERT_LOCKED(sc) mtx_assert(&(sc)->lock, MA_OWNED)
extern int iicbus_generic_intr(device_t dev, int event, char *buf);
extern driver_t iicbus_driver;
extern devclass_t iicbus_devclass;
#endif