acpi-lcd.patch

diff -r f7dfc146779d sys/src/cmd/aux/acpi.c
--- a/sys/src/cmd/aux/acpi.c	Mon Oct 05 14:10:12 2020 -0700
+++ b/sys/src/cmd/aux/acpi.c	Mon Oct 12 21:51:06 2020 +0300
@@ -1,5 +1,6 @@
 #include <u.h>
 #include <libc.h>
+#include <stdio.h>
 #include <fcall.h>
 #include <thread.h>
 #include <9p.h>
@@ -61,6 +62,7 @@
 	Qroot = 0,
 	Qbattery,
 	Qcputemp,
+	Qlcd,
 	Qctl,
 };
 
@@ -69,10 +71,14 @@
 static void ctlwrite(Req*);
 static void batteryread(Req*);
 static void tmpread(Req*);
+static void lcdread(Req*);
+static void lcdwrite(Req*);
 
 int ec, mem, iofd[5], nbats, ntherms, rp, wp;
 char *units[] = {"mW", "mA"};
 Battery bats[4];
+void *lcd = nil;
+void *lcdq = nil;
 Thermal therms[4];
 Channel *creq, *cevent;
 Req *rlist, **tailp;
@@ -81,6 +87,7 @@
 	{{Qroot,0,QTDIR},	"/",		DMDIR|0555,	rootread,		nil},
 	{{Qbattery},		"battery",	0444,		batteryread,	nil},
 	{{Qcputemp},		"cputemp",	0444,		tmpread,		nil},
+	{{Qlcd},			"lcd",		0666,		lcdread,		lcdwrite},
 	{{Qctl},			"ctl",		0666,		ctlread,		ctlwrite},
 };
 
@@ -120,6 +127,20 @@
 }
 
 static int
+enumlcd(void *dot, void *)
+{
+	lcd = dot;
+	return 1;
+}
+
+static int
+enumlcdq(void *dot, void *)
+{
+	lcdq = dot;
+	return 1;
+}
+
+static int
 enumbat(void *dot, void *)
 {
 	void *p, *r, **rr;
@@ -280,6 +301,58 @@
 	respond(r, nil);
 }
 
+static int
+lcdcur(void)
+{
+	void *r;
+	if (lcdq == nil)
+		return -1;
+	if (amleval(lcdq, "", &r) >= 0)
+			return amlint(r) & 0xff;
+	return -1;
+}
+
+static void
+lcdread(Req *req)
+{
+	char buf[32];
+	int cur = lcdcur();
+	if (cur != -1) {
+		sprintf(buf, "%d\n", cur&0xff);
+		readstr(req, buf);
+		respond(req, nil);
+		return;
+	}
+	respond(req, "no.");
+}
+static void
+lcdwrite(Req *r)
+{
+	uchar *p;
+	int n, cur;
+	char buf[64];
+	if (lcd == nil) {
+		respond(r, "no.");
+		return;
+	}
+	p = (uchar*)r->ifcall.data;
+	n = r->ifcall.count;
+	if (n >= sizeof(buf))
+		n = sizeof(buf) - 1;
+	memmove(buf, p, n);
+	buf[n] = 0;
+	cur = lcdcur();
+	if (*buf == '+' && cur != -1) {
+		cur ++;
+	} else if (*buf == '-' && cur != -1) {
+		cur --;
+	} else {
+		cur = atoi(buf);
+	}
+	amleval(lcd, "i", cur, nil);
+	respond(r, nil);
+}
+
 static void
 ctlread(Req *r)
 {
@@ -379,7 +452,7 @@
 			return;
 		}
 		break;
-
+	case Qlcd:
 	case Qctl:
 		if((r->ifcall.mode & ~(OTRUNC|OREAD|OWRITE|ORDWR)) == 0){
 			respond(r, nil);
@@ -539,6 +612,8 @@
 	amlenum(amlroot, "_HID", enumec, nil);
 	amlenum(amlroot, "_BIF", enumbat, nil);
 	amlenum(amlroot, "_PSL", enumtmp, nil);
+	amlenum(amlroot, "_BCM", enumlcd, nil);
+	amlenum(amlroot, "_BQC", enumlcdq, nil);
 
 	threadpostmountsrv(&fs, srv, mtpt, MREPL);
 	threadexits(nil);