os/doc
3
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Update the sample 'echo' character device driver for 5.x:

Browse source 
- Use an dynamic major number rather than a static one.
- Use 'struct cdev *' rather than 'dev_t'.
- Add d_version field to echo_devsw.
- Use malloc()/free() rather than the macros.

Submitted by:	Karl Andersson karland at home dot se (2,3)
This commit is contained in:
John Baldwin 2004-10-29 19:59:24 +00:00
parent 631dc54dfb
commit 53bd474e4d
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=22728
1 changed files with 10 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

21
en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.sgml
View file

@ -364,7 +364,6 @@ DEV_MODULE(echo,echo_loader,NULL);</programlisting>
#include &lt;sys/malloc.h&gt;
#define BUFFERSIZE 256
#define CDEV_MAJOR 33
/* Function prototypes */
@ -375,12 +374,12 @@ static d_write_t echo_write;
/* Character device entry points */
static struct cdevsw echo_cdevsw = {
.d_version = D_VERSION,
.d_open = echo_open,
.d_close = echo_close,
.d_maj = CDEV_MAJOR,
.d_name = "echo",
.d_read = echo_read,
.d_write = echo_write
.d_write = echo_write,
.d_name = "echo",
};
typedef struct s_echo {
@ -389,7 +388,7 @@ typedef struct s_echo {
} t_echo;
/* vars */
static dev_t echo_dev;
static struct cdev *echo_dev;
static int count;
static t_echo *echomsg;
@ -415,12 +414,12 @@ echo_loader(struct module *m, int what, void *arg)
0600,
"echo");
/* kmalloc memory for use by this driver */
MALLOC(echomsg, t_echo *, sizeof(t_echo), M_ECHOBUF, M_WAITOK);
echomsg = malloc(sizeof(t_echo), M_ECHOBUF, M_WAITOK);
printf("Echo device loaded.\n");
break;
case MOD_UNLOAD:
destroy_dev(echo_dev);
FREE(echomsg,M_ECHOBUF);
free(echomsg, M_ECHOBUF);
printf("Echo device unloaded.\n");
break;
default:
@ -431,7 +430,7 @@ echo_loader(struct module *m, int what, void *arg)
}
static int
echo_open(dev_t dev, int oflags, int devtype, struct thread *p)
echo_open(struct cdev *dev, int oflags, int devtype, struct thread *p)
{
int err = 0;
@ -440,7 +439,7 @@ echo_open(dev_t dev, int oflags, int devtype, struct thread *p)
}
static int
echo_close(dev_t dev, int fflag, int devtype, struct thread *p)
echo_close(struct cdev *dev, int fflag, int devtype, struct thread *p)
{
uprintf("Closing device \"echo.\"\n");
return(0);
@ -453,7 +452,7 @@ echo_close(dev_t dev, int fflag, int devtype, struct thread *p)
*/
static int
echo_read(dev_t dev, struct uio *uio, int ioflag)
echo_read(struct cdev *dev, struct uio *uio, int ioflag)
{
int err = 0;
int amt;
@ -476,7 +475,7 @@ echo_read(dev_t dev, struct uio *uio, int ioflag)
*/
static int
echo_write(dev_t dev, struct uio *uio, int ioflag)
echo_write(struct cdev *dev, struct uio *uio, int ioflag)
{
int err = 0;