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1992/0527/pc/devvga.c (diff list | history)

pc/devvga.c on 1992/0527
1992/0527    
#include	"u.h" 
#include	"../port/lib.h" 
#include	"mem.h" 
#include	"dat.h" 
#include	"fns.h" 
#include	"io.h" 
#include	"../port/error.h" 
 
#include	"devtab.h" 
 
/* 
 *  Driver for various VGA cards 
 */ 
 
char	monitor[NAMELEN];	/* monitor name and type */ 
char	vgacard[NAMELEN];	/* vga card type */ 
struct screeninfo { 
	int	maxx, maxy;	/* current bits per screen */ 
	int	packed;		/* 0=planar, 1=packed */ 
	int	interlaced;	/* != 0 if interlaced */ 
} screeninfo; 
 
enum { 
	Qdir=		0, 
	Qvgamonitor=	1, 
	Qvgasize=	2, 
	Qvgatype=	3, 
	Qvgaportio=	4, 
	Nvga=		4, 
}; 
 
Dirtab vgadir[]={ 
	"vgamonitor",	{Qvgamonitor},	0,		0666, 
	"vgatype",	{Qvgatype},	0,		0666, 
	"vgasize",	{Qvgasize},	0,		0666, 
	"vgaportio",	{Qvgaportio},	0,		0666, 
}; 
 
/* a routine from ../port/devcons.c */ 
extern	int readstr(ulong, char *, ulong, char *); 
 
void 
vgasetup(void) { 
} 
 
void 
vgareset(void) { 
	strcpy(monitor, "generic"); 
	strcpy(vgacard, "generic"); 
	screeninfo.maxx = 640; 
	screeninfo.maxy = 480; 
	screeninfo.packed = 0; 
	screeninfo.interlaced = 0; 
} 
 
void 
vgainit(void) 
{ 
} 
 
Chan* 
vgaattach(char *upec) 
{ 
	return devattach('v', upec); 
} 
 
Chan* 
vgaclone(Chan *c, Chan *nc) 
{ 
	return devclone(c, nc); 
} 
 
int 
vgawalk(Chan *c, char *name) 
{ 
	return devwalk(c, name, vgadir, Nvga, devgen); 
} 
 
void 
vgastat(Chan *c, char *dp) 
{ 
	switch(c->qid.path){ 
	default: 
		devstat(c, dp, vgadir, Nvga, devgen); 
		break; 
	} 
} 
 
Chan* 
vgaopen(Chan *c, int omode) 
{ 
	switch(c->qid.path){ 
	case Qvgamonitor: 
	case Qvgatype: 
	case Qvgasize: 
	case Qvgaportio: 
		break; 
	} 
 
	return devopen(c, omode, vgadir, Nvga, devgen); 
} 
 
void 
vgacreate(Chan *c, char *name, int omode, ulong perm) 
{ 
	error(Eperm); 
} 
 
void 
vgaclose(Chan *c) 
{ 
} 
 
long 
vgaread(Chan *c, void *buf, long n, ulong offset) 
{ 
	char obuf[60]; 
	switch(c->qid.path&~CHDIR){ 
	case Qdir: 
		return devdirread(c, buf, n, vgadir, Nvga, devgen); 
	case Qvgamonitor: 
		return readstr(offset, buf, n, monitor); 
	case Qvgatype: 
		return readstr(offset, buf, n, vgacard); 
	case Qvgasize: 
		sprint(obuf, "%dx%d%x%d %s", 
			screeninfo.maxx, screeninfo.maxy, 
			screeninfo.packed ? 16 : 256, 
			screeninfo.interlaced ? "interlaced" : "non-interlaced"); 
		return readstr(offset, buf, n, obuf); 
	case Qvgaportio: 
		return 0; 
	} 
} 
 
long 
vgawrite(Chan *c, void *va, long n, ulong offset) 
{ 
	if(offset != 0) 
		error(Ebadarg); 
	switch(c->qid.path&~CHDIR){ 
	case Qdir: 
		error(Eperm); 
	case Qvgamonitor: 
	case Qvgatype: 
	case Qvgasize: 
	case Qvgaportio: 
		return 0; 
	} 
} 
 
void 
vgaremove(Chan *c) 
{ 
	error(Eperm); 
} 
 
void 
vgawstat(Chan *c, char *dp) 
{ 
	error(Eperm); 
} 


source code copyright © 1990-2005 Lucent Technologies; see license
Plan 9 distribution
comments to russ cox (rsc@swtch.com)