Эта глава посвящена механизмам FreeBSD по написанию
драйверов устройств, работающих на шине PCI.
Здесь находится информация о том, как код шины PCI
проходит по неподключенным устройствам и распознает
возможность загруженного драйвера kld выполнить подключение
к какому-либо из них.
/*
* Simple KLD to play with the PCI functions.
*
* Murray Stokely
*/
#define MIN(a,b) (((a) < (b)) ? (a) : (b))
#include <sys/types.h>
#include <sys/module.h>
#include <sys/systm.h> /* uprintf */
#include <sys/errno.h>
#include <sys/param.h> /* defines used in kernel.h */
#include <sys/kernel.h> /* types used in module initialization */
#include <sys/conf.h> /* cdevsw struct */
#include <sys/uio.h> /* uio struct */
#include <sys/malloc.h>
#include <sys/bus.h> /* structs, prototypes for pci bus stuff */
#include <pci/pcivar.h> /* For get_pci macros! */
/* Function prototypes */
d_open_t mypci_open;
d_close_t mypci_close;
d_read_t mypci_read;
d_write_t mypci_write;
/* Character device entry points */
static struct cdevsw mypci_cdevsw = {
mypci_open,
mypci_close,
mypci_read,
mypci_write,
noioctl,
nopoll,
nommap,
nostrategy,
"mypci",
36, /* reserved for lkms - /usr/src/sys/conf/majors */
nodump,
nopsize,
D_TTY,
-1
};
/* vars */
static dev_t sdev;
/* We're more interested in probe/attach than with
open/close/read/write at this point */
int
mypci_open(dev_t dev, int oflags, int devtype, struct proc *p)
{
int err = 0;
uprintf("Opened device "mypci" successfully.n");
return(err);
}
int
mypci_close(dev_t dev, int fflag, int devtype, struct proc *p)
{
int err=0;
uprintf("Closing device "mypci."n");
return(err);
}
int
mypci_read(dev_t dev, struct uio *uio, int ioflag)
{
int err = 0;
uprintf("mypci read!n");
return err;
}
int
mypci_write(dev_t dev, struct uio *uio, int ioflag)
{
int err = 0;
uprintf("mypci write!n");
return(err);
}
/* PCI Support Functions */
/*
* Return identification string if this is device is ours.
*/
static int
mypci_probe(device_t dev)
{
uprintf("MyPCI Proben"
"Vendor ID : 0x%xn"
"Device ID : 0x%xn",pci_get_vendor(dev),pci_get_device(dev));
if (pci_get_vendor(dev) == 0x11c1) {
uprintf("We've got the Winmodem, probe successful!n");
return 0;
}
return ENXIO;
}
/* Attach function is only called if the probe is successful */
static int
mypci_attach(device_t dev)
{
uprintf("MyPCI Attach for : deviceID : 0x%xn",pci_get_vendor(dev));
sdev = make_dev(&mypci_cdevsw,
0,
UID_ROOT,
GID_WHEEL,
0600,
"mypci");
uprintf("Mypci device loaded.n");
return ENXIO;
}
/* Detach device. */
static int
mypci_detach(device_t dev)
{
uprintf("Mypci detach!n");
return 0;
}
/* Called during system shutdown after sync. */
static int
mypci_shutdown(device_t dev)
{
uprintf("Mypci shutdown!n");
return 0;
}
/*
* Device suspend routine.
*/
static int
mypci_suspend(device_t dev)
{
uprintf("Mypci suspend!n");
return 0;
}
/*
* Device resume routine.
*/
static int
mypci_resume(device_t dev)
{
uprintf("Mypci resume!n");
return 0;
}
static device_method_t mypci_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, mypci_probe),
DEVMETHOD(device_attach, mypci_attach),
DEVMETHOD(device_detach, mypci_detach),
DEVMETHOD(device_shutdown, mypci_shutdown),
DEVMETHOD(device_suspend, mypci_suspend),
DEVMETHOD(device_resume, mypci_resume),
{ 0, 0 }
};
static driver_t mypci_driver = {
"mypci",
mypci_methods,
0,
/* sizeof(struct mypci_softc), */
};
static devclass_t mypci_devclass;
DRIVER_MODULE(mypci, pci, mypci_driver, mypci_devclass, 0, 0);
Дополнительная информация