freebsd-dev/sys/dev/gpio/gpioc.c
Luiz Otavio O Souza 4723c14fa9 Convert gpioc to use the make_dev_s(9) KPI. This fix a possible race where
si_drv1 can be accessed before it gets set.

This is inspired on r311700.

MFC after:	3 days
2017-01-08 20:41:32 +00:00

218 lines
5.6 KiB
C

/*-
* Copyright (c) 2009 Oleksandr Tymoshenko <gonzo@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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/gpio.h>
#include <sys/ioccom.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <dev/gpio/gpiobusvar.h>
#include "gpio_if.h"
#include "gpiobus_if.h"
#undef GPIOC_DEBUG
#ifdef GPIOC_DEBUG
#define dprintf printf
#else
#define dprintf(x, arg...)
#endif
static int gpioc_probe(device_t dev);
static int gpioc_attach(device_t dev);
static int gpioc_detach(device_t dev);
static d_ioctl_t gpioc_ioctl;
static struct cdevsw gpioc_cdevsw = {
.d_version = D_VERSION,
.d_ioctl = gpioc_ioctl,
.d_name = "gpioc",
};
struct gpioc_softc {
device_t sc_dev; /* gpiocX dev */
device_t sc_pdev; /* gpioX dev */
struct cdev *sc_ctl_dev; /* controller device */
int sc_unit;
};
static int
gpioc_probe(device_t dev)
{
device_set_desc(dev, "GPIO controller");
return (0);
}
static int
gpioc_attach(device_t dev)
{
int err;
struct gpioc_softc *sc;
struct make_dev_args devargs;
sc = device_get_softc(dev);
sc->sc_dev = dev;
sc->sc_pdev = device_get_parent(dev);
sc->sc_unit = device_get_unit(dev);
make_dev_args_init(&devargs);
devargs.mda_devsw = &gpioc_cdevsw;
devargs.mda_uid = UID_ROOT;
devargs.mda_gid = GID_WHEEL;
devargs.mda_mode = 0600;
devargs.mda_si_drv1 = sc;
err = make_dev_s(&devargs, &sc->sc_ctl_dev, "gpioc%d", sc->sc_unit);
if (err != 0) {
printf("Failed to create gpioc%d", sc->sc_unit);
return (ENXIO);
}
return (0);
}
static int
gpioc_detach(device_t dev)
{
struct gpioc_softc *sc = device_get_softc(dev);
int err;
if (sc->sc_ctl_dev)
destroy_dev(sc->sc_ctl_dev);
if ((err = bus_generic_detach(dev)) != 0)
return (err);
return (0);
}
static int
gpioc_ioctl(struct cdev *cdev, u_long cmd, caddr_t arg, int fflag,
struct thread *td)
{
device_t bus;
int max_pin, res;
struct gpioc_softc *sc = cdev->si_drv1;
struct gpio_pin pin;
struct gpio_req req;
uint32_t caps;
bus = GPIO_GET_BUS(sc->sc_pdev);
if (bus == NULL)
return (EINVAL);
switch (cmd) {
case GPIOMAXPIN:
max_pin = -1;
res = GPIO_PIN_MAX(sc->sc_pdev, &max_pin);
bcopy(&max_pin, arg, sizeof(max_pin));
break;
case GPIOGETCONFIG:
bcopy(arg, &pin, sizeof(pin));
dprintf("get config pin %d\n", pin.gp_pin);
res = GPIO_PIN_GETFLAGS(sc->sc_pdev, pin.gp_pin,
&pin.gp_flags);
/* Fail early */
if (res)
break;
GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &pin.gp_caps);
GPIOBUS_PIN_GETNAME(bus, pin.gp_pin, pin.gp_name);
bcopy(&pin, arg, sizeof(pin));
break;
case GPIOSETCONFIG:
bcopy(arg, &pin, sizeof(pin));
dprintf("set config pin %d\n", pin.gp_pin);
res = GPIO_PIN_GETCAPS(sc->sc_pdev, pin.gp_pin, &caps);
if (res == 0)
res = gpio_check_flags(caps, pin.gp_flags);
if (res == 0)
res = GPIO_PIN_SETFLAGS(sc->sc_pdev, pin.gp_pin,
pin.gp_flags);
break;
case GPIOGET:
bcopy(arg, &req, sizeof(req));
res = GPIO_PIN_GET(sc->sc_pdev, req.gp_pin,
&req.gp_value);
dprintf("read pin %d -> %d\n",
req.gp_pin, req.gp_value);
bcopy(&req, arg, sizeof(req));
break;
case GPIOSET:
bcopy(arg, &req, sizeof(req));
res = GPIO_PIN_SET(sc->sc_pdev, req.gp_pin,
req.gp_value);
dprintf("write pin %d -> %d\n",
req.gp_pin, req.gp_value);
break;
case GPIOTOGGLE:
bcopy(arg, &req, sizeof(req));
dprintf("toggle pin %d\n",
req.gp_pin);
res = GPIO_PIN_TOGGLE(sc->sc_pdev, req.gp_pin);
break;
case GPIOSETNAME:
bcopy(arg, &pin, sizeof(pin));
dprintf("set name on pin %d\n", pin.gp_pin);
res = GPIOBUS_PIN_SETNAME(bus, pin.gp_pin,
pin.gp_name);
break;
default:
return (ENOTTY);
break;
}
return (res);
}
static device_method_t gpioc_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, gpioc_probe),
DEVMETHOD(device_attach, gpioc_attach),
DEVMETHOD(device_detach, gpioc_detach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, bus_generic_suspend),
DEVMETHOD(device_resume, bus_generic_resume),
DEVMETHOD_END
};
driver_t gpioc_driver = {
"gpioc",
gpioc_methods,
sizeof(struct gpioc_softc)
};
devclass_t gpioc_devclass;
DRIVER_MODULE(gpioc, gpio, gpioc_driver, gpioc_devclass, 0, 0);
MODULE_VERSION(gpioc, 1);