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Various and sundry cleanups to the sample PCI driver:

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- Split the first section into sub-sections instead of just paragraphs.
- Include a makefile for a kernel module for the sample driver and explain
  how to use 'make', 'make load', and 'make unload'.
- Use 'struct cdev *' rather than 'dev_t'.
- Add missing d_version to cdevsw.
- Explain how to use si_drv1 in struct cdev to get from a cdev back to the
  softc.
- Add a softc and move the cdev pointer into the softc.  Given the cdev
  a unique name and minor number for each device.
- Use better comments in several places.
- Actually call device_set_desc() in probe, and use BUS_PROBE_DEFAULT
  rather than 0.
- Add missing call to destroy_dev() in detach.
- Use DEFINE_CLASS_0.

PR:		docs/90830
Submitted by:	Marius Nuennerich marius dot nuennerich at gmx dot net
This commit is contained in:
John Baldwin 2006-01-06 21:29:52 +00:00
parent 591b393168
commit d5cc81900b
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=26788
1 changed files with 102 additions and 52 deletions
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154
en_US.ISO8859-1/books/arch-handbook/pci/chapter.sgml
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@ -19,40 +19,48 @@
the unattached devices and see if a newly loaded kld will attach
to any of them.</para>
<sect2>
<title>Sample Driver Source (<filename>mypci.c</filename>)</title>
<programlisting>/*
* Simple KLD to play with the PCI functions.
*
* Murray Stokely
*/
#define MIN(a,b) (((a) &lt; (b)) ? (a) : (b))
#include &lt;sys/param.h&gt; /* defines used in kernel.h */
#include &lt;sys/param.h&gt; /* defines used in kernel.h */
#include &lt;sys/module.h&gt;
#include &lt;sys/systm.h&gt;
#include &lt;sys/errno.h&gt;
#include &lt;sys/kernel.h&gt; /* types used in module initialization */
#include &lt;sys/conf.h&gt; /* cdevsw struct */
#include &lt;sys/uio.h&gt; /* uio struct */
#include &lt;sys/kernel.h&gt; /* types used in module initialization */
#include &lt;sys/conf.h&gt; /* cdevsw struct */
#include &lt;sys/uio.h&gt; /* uio struct */
#include &lt;sys/malloc.h&gt;
#include &lt;sys/bus.h&gt; /* structs, prototypes for pci bus stuff */
#include &lt;sys/bus.h&gt; /* structs, prototypes for pci bus stuff */
#include &lt;machine/bus.h&gt;
#include &lt;sys/rman.h&gt;
#include &lt;machine/resource.h&gt;
#include &lt;dev/pci/pcivar.h&gt; /* For get_pci macros! */
#include &lt;dev/pci/pcivar.h&gt; /* For pci_get macros! */
#include &lt;dev/pci/pcireg.h&gt;
/* The softc holds our per-instance data. */
struct mypci_softc {
device_t my_dev;
struct cdev *my_cdev;
};
/* Function prototypes */
d_open_t mypci_open;
d_close_t mypci_close;
d_read_t mypci_read;
d_write_t mypci_write;
static d_open_t mypci_open;
static d_close_t mypci_close;
static d_read_t mypci_read;
static d_write_t mypci_write;
/* Character device entry points */
static struct cdevsw mypci_cdevsw = {
.d_version = D_VERSION,
.d_open = mypci_open,
.d_close = mypci_close,
.d_read = mypci_read,
@ -60,62 +68,73 @@ static struct cdevsw mypci_cdevsw = {
.d_name = "mypci",
};
/* vars */
static dev_t sdev;
/* We're more interested in probe/attach than with
open/close/read/write at this point */
/*
* In the cdevsw routines, we find our softc by using the si_drv1 member
* of struct cdev. We set this variable to point to our softc in our
* attach routine when we create the /dev entry.
*/
int
mypci_open(dev_t dev, int oflags, int devtype, d_thread_t *td)
mypci_open(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
{
int err = 0;
struct mypci_softc *sc;
printf("Opened device \"mypci\" successfully.\n");
return (err);
/* Look up our softc. */
sc = dev-&gt;si_drv1;
device_printf(sc-&gt;my_dev, "Opened successfully.\n");
return (0);
}
int
mypci_close(dev_t dev, int fflag, int devtype, d_thread_t *td)
mypci_close(struct cdev *dev, int fflag, int devtype, d_thread_t *td)
{
int err = 0;
struct mypci_softc *sc;
printf("Closing device \"mypci.\"\n");
return (err);
/* Look up our softc. */
sc = dev-&gt;si_drv1;
device_printf(sc-&gt;my_dev, "Closed.\n");
return (0);
}
int
mypci_read(dev_t dev, struct uio *uio, int ioflag)
mypci_read(struct cdev *dev, struct uio *uio, int ioflag)
{
int err = 0;
struct mypci_softc *sc;
printf("mypci read!\n");
return (err);
/* Look up our softc. */
sc = dev-&gt;si_drv1;
device_printf(sc-&gt;my_dev, "Asked to read %d bytes.\n", uio-&gt;uio_resid);
return (0);
}
int
mypci_write(dev_t dev, struct uio *uio, int ioflag)
mypci_write(struct cdev *dev, struct uio *uio, int ioflag)
{
int err = 0;
struct mypci_softc *sc;
printf("mypci write!\n");
/* Look up our softc. */
sc = dev-&gt;si_drv1;
device_printf(sc-&gt;my_dev, "Asked to write %d bytes.\n", uio-&gt;uio_resid);
return (err);
}
/* PCI Support Functions */
/*
* Return identification string if this is device is ours.
* Compare the device ID of this device against the IDs that this driver
* supports. If there is a match, set the description and return success.
*/
static int
mypci_probe(device_t dev)
{
device_printf(dev, "MyPCI Probe\nVendor ID : 0x%x\nDevice ID : 0x%x\n",
pci_get_vendor(dev), pci_get_device(dev));
if (pci_get_vendor(dev) == 0x11c1) {
printf("We've got the Winmodem, probe successful!\n");
return (0);
device_set_desc(dev, "WinModem");
return (BUS_PROBE_DEFAULT);
}
return (ENXIO);
}
@ -125,10 +144,22 @@ mypci_probe(device_t dev)
static int
mypci_attach(device_t dev)
{
struct mypci_softc *sc;
printf("MyPCI Attach for : deviceID : 0x%x\n",pci_get_vendor(dev));
sdev = make_dev(<literal>&amp;</literal>mypci_cdevsw, 0, UID_ROOT,
GID_WHEEL, 0600, "mypci");
/* Look up our softc and initialize its fields. */
sc = device_get_softc(dev);
sc-&gt;my_dev = dev;
/*
* Create a /dev entry for this device. The kernel will assign us
* a major number automatically. We use the unit number of this
* device as the minor number and name the character device
* "mypci&lt;unit&gt;".
*/
sc-&gt;my_cdev = make_dev(<literal>&amp;</literal>mypci_cdevsw, device_get_unit(dev),
UID_ROOT, GID_WHEEL, 0600, "mypci%u", device_get_unit(dev));
printf("Mypci device loaded.\n");
return (ENXIO);
}
@ -138,7 +169,11 @@ mypci_attach(device_t dev)
static int
mypci_detach(device_t dev)
{
struct mypci_softc *sc;
/* Teardown the state in our softc created in our attach routine. */
sc = device_get_softc(dev);
destroy_dev(sc-&gt;my_cdev);
printf("Mypci detach!\n");
return (0);
}
@ -167,7 +202,6 @@ mypci_suspend(device_t dev)
/*
* Device resume routine.
*/
static int
mypci_resume(device_t dev)
{
@ -188,27 +222,43 @@ static device_method_t mypci_methods[] = {
{ 0, 0 }
};
static driver_t mypci_driver = {
"mypci",
mypci_methods,
0,
/* sizeof(struct mypci_softc), */
};
static devclass_t mypci_devclass;
DEFINE_CLASS_0(mypci, mypci_driver, mypci_methods, sizeof(struct mypci_softc));
DRIVER_MODULE(mypci, pci, mypci_driver, mypci_devclass, 0, 0);</programlisting>
</sect2>
<para>Additional Resources
<itemizedlist>
<listitem><simpara><ulink url="http://www.pcisig.org/">PCI
Special Interest Group</ulink></simpara></listitem>
<sect2>
<title><filename>Makefile</filename> for Sample Driver</title>
<listitem><simpara>PCI System Architecture, Fourth Edition by
Tom Shanley, et al.</simpara></listitem>
<programlisting># Makefile for mypci driver
</itemizedlist>
</para>
KMOD= mypci
SRCS= mypci.c
SRCS+= device_if.h bus_if.h pci_if.h
.include &lt;bsd.kmod.mk&gt;</programlisting>
<para>If you place the above source file and
<filename>Makefile</filename> into a directory, you may run
<command>make</command> to compile the sample driver.
Additionally, you may run <command>make load</command> to load
the driver into the currently running kernel and <command>make
unload</command> to unload the driver after it is
loaded.</para>
</sect2>
<sect2>
<title>Additional Resources</title>
<itemizedlist>
<listitem><simpara><ulink url="http://www.pcisig.org/">PCI
Special Interest Group</ulink></simpara></listitem>
<listitem><simpara>PCI System Architecture, Fourth Edition by
Tom Shanley, et al.</simpara></listitem>
</itemizedlist>
</sect2>
</sect1>
<sect1 id="pci-bus">