1 files changed, 497 insertions, 0 deletions
diff --git a/os/mpc/devtouch.c b/os/mpc/devtouch.c
new file mode 100644
index 00000000..b11aecc8
--- /dev/null
+++ b/os/mpc/devtouch.c
@@ -0,0 +1,497 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "io.h"
+#include "../port/error.h"
+
+#define	DPRINT	if(0)print
+#define	THREEBUT	0	/* !=0, enable 3-button emulation (see below) */
+
+/*
+ * DynaPro touch panel and Maxim MAX192 A/D converter on
+ * York Electronics Centre's BRD/98/024 (Version A) interface,
+ * accessed via mpc8xx SPI interface (see spi.c).
+ *
+ * The highest level of the driver is derived from the ARM/UCB touch panel driver,
+ * simplified because of the differences between the panels.
+ */
+
+/*
+ * Values determined by interface board
+ */
+enum {
+	/* MAX192 control words */
+	MeasureX =	(1<<7)|(0<<6)|(1<<3)|(1<<2)|3,	/* start, channel 0, unipolar, single-ended, external clock */
+	MeasureY =	(1<<7)|(1<<6)|(1<<3)|(1<<2)|3,	/* start, channel 1, unipolar, single-ended, external clock */
+
+	/* port B bits */
+	ADselect = IBIT(16),	/* chip select to MAX192, active low */
+
+	/* port C bits */
+	Xenable =	1<<2,	/* PC13: TOUCH_XEN, active low */
+	Yenable =	1<<3,	/* PC12: TOUCH_YEN, active low */
+	Touched = 1<<10,	/* PC5: contact detect, active low */
+
+	/* interrupt control via port C */
+	TouchIRQ=	2,	/* parallel i/o - PC5 */
+	TouchEnable=	1<<TouchIRQ,	/* mask for cimr */
+
+	/* other parameters */
+	Nconverge =	10,	/* maximum iterations for convergence */
+	MaxDelta =	2,	/* acceptable change in X/Y between iterations */
+};
+
+/*
+ * ADC interface via SPI (see MAX192 data sheet)
+ *	select the ADC
+ *	send 8-bit control word and two zero bytes to clock the conversion
+ *	receive three data bytes
+ *	deselect the ADC and return the result
+ */
+static int
+getcoord(int cw)
+{
+	uchar tbuf[3], rbuf[3];
+	IMM *io;
+	int nr;
+
+	tbuf[0] = cw;
+	tbuf[1] = 0;
+	tbuf[2] = 0;
+	io = ioplock();
+	io->pbdat &= ~ADselect;
+	iopunlock();
+	nr = spioutin(tbuf, sizeof(tbuf), rbuf);
+	io = ioplock();
+	io->pbdat |= ADselect;
+	iopunlock();
+	if(nr != 3)
+		return -1;
+	return ((rbuf[1]<<8)|rbuf[2])>>5;
+}
+
+/*
+ * keep reading the a/d until the value stabilises
+ */
+static int
+dejitter(int enable, int cw)
+{
+	int i, diff, prev, v;
+	IMM *io;
+
+	io = ioplock();
+	io->pcdat &= ~enable;	/* active low */
+	iopunlock();
+
+	i = 0;
+	v = getcoord(cw);
+	do{
+		prev = v;
+		v = getcoord(cw);
+		diff = v - prev;
+		if(diff < 0)
+			diff = -diff;
+	}while(diff >= MaxDelta && ++i <= Nconverge);
+
+	io = ioplock();
+	io->pcdat |= enable;
+	iopunlock();
+	return v;
+}
+
+static void
+adcreset(void)
+{
+	IMM *io;
+
+	/* select port pins */
+	io = ioplock();
+	io->pcdir &= ~(Xenable|Yenable);	/* ensure set to input before changing state */
+	io->pcpar &= ~(Xenable|Yenable);
+	io->pcdat |= Xenable|Yenable;
+	io->pcdir |= Xenable;	/* change enable bits to output one at a time to avoid both being low at once (could damage panel) */
+	io->pcdat |= Xenable;	/* ensure it's high after making it an output */
+	io->pcdir |= Yenable;
+	io->pcdat |= Yenable;	/* ensure it's high after making it an output */
+	io->pcso &= ~(Xenable|Yenable);
+	io->pbdat |= ADselect;
+	io->pbpar &= ~ADselect;
+	io->pbdir |= ADselect;
+	iopunlock();
+}
+
+/*
+ * high-level touch panel interface
+ */
+
+/* to and from fixed point */
+#define	FX(n)	((n)<<16)
+#define	XF(v)		((v)>>16)
+
+typedef struct Touch Touch;
+
+struct Touch {
+	Lock;
+	Rendez	r;
+	int	m[2][3];	/* transformation matrix */
+	int	rate;
+	int	down;
+	int	raw_count;
+	int	valid_count;
+	int	wake_time;
+	int	sleep_time;
+};
+
+static Touch touch = {
+	{0},
+	.r {0},
+	.m {{FX(1), 0, 0},{0, FX(1), 0}},	/* default is 1:1 */
+	.rate 20,	/* milliseconds */
+};
+
+/*
+ * panel-touched state and interrupt
+ */
+
+static int
+touching(void)
+{
+	eieio();
+	return (m->iomem->pcdat & Touched) == 0;
+}
+
+static int
+ispendown(void*)
+{
+	return touch.down || touching();
+}
+
+static void
+touchintr(Ureg*, void*)
+{
+	if((m->iomem->pcdat & Touched) == 0){
+		m->iomem->cimr &= ~TouchEnable;	/* mask interrupts when reading pen */
+		touch.down = 1;
+		wakeup(&touch.r);
+	}
+}
+
+static void
+touchenable(void)
+{
+	IMM *io;
+ 
+	io = ioplock();
+	io->cimr |= TouchEnable;
+	iopunlock();
+}
+
+/*
+ * touchctl commands:
+ *	X a b c	- set X transformation
+ *	Y d e f	- set Y transformation
+ *	s<delay>		- set sample delay in millisec per sample
+ *	r<delay>		- set read delay in microsec
+ *	R<l2nr>			- set log2 of number of readings to average
+ */
+
+enum{
+	Qdir,
+	Qtouchctl,
+	Qtouchstat,
+	Qtouch,
+};
+
+Dirtab touchdir[]={
+	".",	{Qdir, 0, QTDIR}, 0, 0555,
+	"touchctl",	{Qtouchctl, 0}, 	0,	0666,
+	"touchstat",	{Qtouchstat, 0}, 	0,	0444,
+	"touch",	{Qtouch, 0},	0,	0444,
+};
+
+static int
+ptmap(int *m, int x, int y)
+{
+	return XF(m[0]*x + m[1]*y + m[2]);
+}
+
+/*
+ * read a point from the touch panel;
+ * returns true iff the point is valid, otherwise x, y aren't changed
+ */
+static int
+touchreadxy(int *fx, int *fy)
+{
+	int rx, ry;
+
+	if(touching()){
+		rx = dejitter(Xenable, MeasureX);
+		ry = dejitter(Yenable, MeasureY);
+		microdelay(40);
+		if(rx >=0 && ry >= 0){
+			if(0)
+				print("touch %d %d\n", rx, ry);
+			*fx = ptmap(touch.m[0], rx, ry);
+			*fy = ptmap(touch.m[1], rx, ry);
+			touch.raw_count++;
+			return 1;
+		}
+	}
+	return 0;
+}
+
+#define	timer_start()	0	/* could use TBL if necessary */
+#define	tmr2us(n)	0
+
+static void
+touchproc(void*)
+{
+	int b, i, x, y;
+	ulong t1, t2;
+
+	t1 = timer_start();
+	b = 1;
+	for(;;) {
+		//setpri(PriHi);
+		do{
+			touch.down = 0;
+			touch.wake_time += (t2 = timer_start())-t1;
+			touchenable();
+			sleep(&touch.r, ispendown, nil);
+			touch.sleep_time += (t1 = timer_start())-t2;
+		}while(!touchreadxy(&x, &y));
+
+		/* 640x480-specific 3-button emulation hack: */
+		if(THREEBUT){
+			if(y > 481) { 
+				b = ((639-x) >> 7);
+				continue;
+			} else if(y < -2) {
+				b = (x >> 7)+3;
+				continue;
+			}
+		}
+
+		DPRINT("#%d %d", x, y);
+		mousetrack(b, x, y, 0);
+		setpri(PriNormal);
+		while(touching()) {
+			for(i=0; i<3; i++)
+				if(touchreadxy(&x, &y)) {
+					DPRINT("*%d %d", x, y);
+					mousetrack(b, x, y, 0);
+					break;
+				}
+			touch.wake_time += (t2 = timer_start())-t1;
+			tsleep(&touch.r, return0, nil, touch.rate);
+			touch.sleep_time += (t1 = timer_start())-t2;
+		}
+		mousetrack(0, x, y, 0);
+		b = 1;	/* go back to just button one for next press */
+	}
+}
+
+static void
+touchreset(void)
+{
+	IMM *io;
+
+	spireset();
+	adcreset();
+	intrenable(VectorCPIC+TouchIRQ, touchintr, &touch, BUSUNKNOWN, "touch");
+
+	/* set i/o pin to interrupt when panel touched */
+	io = ioplock();
+	io->pcdat &= ~Touched;
+	io->pcpar &= ~Touched;
+	io->pcdir &= ~Touched;
+	io->pcso &= ~Touched;
+	io->pcint |= Touched;	/* high-to-low trigger */
+	io->cimr &= ~TouchEnable;	/* touchproc will enable when ready */
+	iopunlock();
+}
+
+static void
+touchinit(void)
+{
+	static int done;
+
+	if(!done){
+		done = 1;
+		kproc( "touchscreen", touchproc, nil, 0);
+	}
+}
+
+static Chan*
+touchattach(char* spec)
+{
+	return devattach('T', spec);
+}
+
+static Walkqid*
+touchwalk(Chan* c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, touchdir, nelem(touchdir), devgen);
+}
+
+static int
+touchstat(Chan* c, uchar* dp, int n)
+{
+	return devstat(c, dp, n, touchdir, nelem(touchdir), devgen);
+}
+
+static Chan*
+touchopen(Chan* c, int omode)
+{
+	omode = openmode(omode);
+	switch((ulong)c->qid.path){
+	case Qtouchctl:
+	case Qtouchstat:
+		if(!iseve())
+			error(Eperm);
+		break;
+	}
+	return devopen(c, omode, touchdir, nelem(touchdir), devgen);
+}
+
+static void	 
+touchclose(Chan*)
+{
+}
+
+static long	 
+touchread(Chan* c, void* buf, long n, vlong offset)
+{
+	char *tmp;
+	int x, y;
+
+	if(c->qid.type & QTDIR)
+		return devdirread(c, buf, n, touchdir, nelem(touchdir), devgen);
+
+	tmp = malloc(READSTR);
+	if(waserror()){
+		free(tmp);
+		nexterror();
+	}
+	switch((ulong)c->qid.path){
+	case Qtouch:
+		if(!touchreadxy(&x, &y))
+			x = y = -1;
+		snprint(tmp, READSTR, "%d %d", x, y);
+		break;
+	case Qtouchctl:
+		snprint(tmp, READSTR, "s%d\nr%d\nR%d\nX %d %d %d\nY %d %d %d\n",
+			touch.rate, 0, 1,
+			touch.m[0][0], touch.m[0][1], touch.m[0][2],
+			touch.m[1][0], touch.m[1][1], touch.m[1][2]);
+		break;
+	case Qtouchstat:
+		snprint(tmp, READSTR, "%d %d\n%d %d\n",
+			touch.raw_count, touch.valid_count, tmr2us(touch.sleep_time), tmr2us(touch.wake_time));
+		touch.raw_count = 0;
+		touch.valid_count = 0;
+		touch.sleep_time = 0;
+		touch.wake_time = 0;
+		break;
+	default:
+		error(Ebadarg);
+		return 0;
+	}
+	n = readstr(offset, buf, n, tmp);
+	poperror();
+	free(tmp);
+	return n;
+}
+
+static void
+dotouchwrite(Chan *c, char *buf)
+{
+	char *field[8];
+	int nf, cmd, pn, m[3], n;
+
+	nf = getfields(buf, field, nelem(field), 1, " \t\n");
+	if(nf <= 0)
+		return;
+	switch((ulong)c->qid.path){
+	case Qtouchctl:
+		cmd = *(field[0])++;
+		pn = *field[0] == 0;
+		switch(cmd) {
+		case 's':
+			n = strtol(field[pn], 0, 0);
+			if(n <= 0)
+				error(Ebadarg);
+			touch.rate = n;
+			break;
+		case 'r':
+			/* touch read delay */
+			break;
+		case 'X':
+		case 'Y':
+			if(nf < pn+2)
+				error(Ebadarg);
+			m[0] = strtol(field[pn], 0, 0);
+			m[1] = strtol(field[pn+1], 0, 0);
+			m[2] = strtol(field[pn+2], 0, 0);
+			memmove(touch.m[cmd=='Y'], m, sizeof(touch.m[0]));
+			break;
+		case 'c':
+		case 'C':
+		case 'v':
+		case 't':
+		case 'e':
+			/* not used */
+			/* break; */
+		default:
+			error(Ebadarg);
+		}
+		break;
+	default:
+		error(Ebadarg);
+		return;
+	}
+}
+
+static long	 
+touchwrite(Chan* c, void* vp, long n, vlong)
+{
+	char buf[64];
+	char *cp, *a;
+	int n0 = n;
+	int bn;
+
+	a = vp;
+	while(n) {
+		bn = (cp = memchr(a, '\n', n))!=nil ? cp-a+1 : n;
+		n -= bn;
+		bn = bn > sizeof(buf)-1 ? sizeof(buf)-1 : bn;
+		memmove(buf, a, bn);
+		buf[bn] = '\0';
+		a = cp;
+		dotouchwrite(c, buf);
+	}
+	return n0-n;
+}
+
+Dev touchdevtab = {
+	'T',
+	"touch",
+
+	touchreset,
+	touchinit,
+	devshutdown,
+	touchattach,
+	touchwalk,
+	touchstat,
+	touchopen,
+	devcreate,
+	touchclose,
+	touchread,
+	devbread,
+	touchwrite,
+	devbwrite,
+	devremove,
+	devwstat,
+};