move and rename MNT Reform 2 support utilies, cat manpages into one

Aux/imx8pm and aux/wm8960 had pretty cryptic names and it made
more sense to use a reform/pm and reform/audio naming, accordingly.

Instead of having special mount points /mnt/pm and /mnt/wm8960,
/dev is used directly, removing the need to do any manual work -
stats(1) will continue showing the CPU temperature, and zuke(1)
will still be able to control the volume, etc.

Brightness controls were changed to a better interface -
/dev/light, where each line contains a "a_thing its_light_value".
This way more parts can be controlled. Right now it's only "lcd",
but later it might be "kbd" and "trackball" as well.

Example of lib/profile:

reform/audio
echo master 80 > /dev/volume

reform/pm
echo lcd 100 > /dev/light

1 files changed, 370 insertions, 0 deletions

diff --git a/sys/src/cmd/reform/audio.c b/sys/src/cmd/reform/audio.c
new file mode 100644
index 000000000..9c73505b6
--- /dev/null
+++ b/sys/src/cmd/reform/audio.c
@@ -0,0 +1,370 @@
+#include <u.h>
+#include <libc.h>
+#include <fcall.h>
+#include <thread.h>
+#include <9p.h>
+
+#define MIN(a,b) (a<b?a:b)
+#define MAX(a,b) (a>b?a:b)
+#define CLAMP(x,a,b) MAX(a,MIN(x,b))
+
+typedef struct Out Out;
+
+enum
+{
+	Dac,
+	Hp,
+	Spk,
+	Nout,
+
+	Ctl = 1,
+	Vol,
+};
+
+struct Out
+{
+	char *name;
+	int volreg;
+	int volmax;
+	int togglemask;
+	void (*toggle)(Out *o, int on);
+	int on;
+	int vol[2];
+};
+
+static char *uid = "audio";
+static int data;
+static int reg1a;
+static int rate = 44100;
+static int ⅓d;
+
+static void
+wr(int a, int v)
+{
+	u8int c;
+
+	//fprint(2, "[0x%x] ← 0x%ux\n", a, v & 0x1ff);
+	c = v & 0xff;
+	if(pwrite(data, &c, 1, a<<1 | ((v>>8)&1)) < 1)
+		fprint(2, "reg %x write failed: %r\n", a);
+}
+
+static void
+classdspk(Out *, int on)
+{
+	wr(0x31, (on ? 3 : 0)<<6 | 0x37); /* class D SPK out */
+}
+
+static void
+toggle(Out *o, int on)
+{
+	if(on)
+		reg1a |= o->togglemask;
+	else
+		reg1a &= ~o->togglemask;
+	wr(0x1a, reg1a);
+	if(o->toggle != nil)
+		o->toggle(o, on);
+	o->on = on;
+}
+
+static Out out[Nout] =
+{
+	[Dac] = {"master", 0x0a, 0xf9, 3<<7, nil, 0},
+	[Hp] = {"hp", 0x02, 0x7f, 3<<5, nil, 0},
+	[Spk] = {"spk", 0x28, 0x7f, 3<<3, classdspk, 0},
+};
+
+static void
+setvol(Out *o, int l, int r)
+{
+	int zc;
+
+	o->vol[0] = l = CLAMP(l, 0, 100);
+	o->vol[1] = r = CLAMP(r, 0, 100);
+	if(l > 0)
+		l += o->volmax - 100;
+	if(r > 0)
+		r += o->volmax - 100;
+
+	zc = o->volmax < 0x80;
+	wr(o->volreg+0, 0<<8 | zc<<7 | l);
+	wr(o->volreg+1, 1<<8 | zc<<7 | r);
+}
+
+static void
+set3d(int x)
+{
+	⅓d = CLAMP(x, 0, 100);
+	x = (⅓d+5)/7;
+	wr(0x10, x<<1 | (x ? 1 : 0)<<0);
+}
+
+static int
+setrate(int s)
+{
+	u32int k;
+
+	if(s != 44100 && s != 48000)
+		return -1;
+
+	/*
+	 * getting DAC ready for s16c2r44100:
+	 *
+	 * mclk₀ = 25Mhz (set in sai)
+	 * pllprescale = /2 → *actual* mclk₁ is 25/2 = 12.5Mhz
+	 * sysclk = 44.1kHz*256 = 11.2896Mhz
+	 *   → dacdiv = /(1*256) = sysclk/(1*256) = 44.1kHz
+	 * f₂ = 4*2*sysclk = 90.3168Mhz
+	 *
+	 * PLL freq ration:
+	 *   R = f₂/mclk₁
+	 *   N = int(R) = 7
+	 *   K = 2²⁴*(R-N) = 3780644.9623
+	 *
+	 * dacdiv = /(1*256) → DAC at max rate
+	 *  → pick bclk rate 1.4112Mhz (sysclk/8)
+	 *  → bclkdiv = /8
+	 *
+	 * class D clk needs to be ~768kHz (700-800)
+	 *  → sysclk/768000 = 14
+	 *  → dclkdiv = /16 → dclk = 705.6kHz
+	 */
+	wr(0x1a, reg1a = reg1a & ~(1<<0)); /* disable pll */
+
+	wr(0x04,
+		0<<3 | /* dacdiv → sysclk/(1*256) = 44100 */
+		2<<1 | /* sysclkdiv → /2 */
+		1<<0 | /* clksel → pll output */
+		0
+	);
+	wr(0x34,
+		1<<5 | /* enable fractional mode */
+		1<<4 | /* pllprescale */
+		7<<0 | /* N */
+		0
+	);
+	k = s == 44100 ? 3780645 : 14500883; /* K */
+	wr(0x35, (k>>16) & 0xff);
+	wr(0x36, (k>>8) & 0xff);
+	wr(0x37, k & 0xff);
+
+	wr(0x08, 7<<6 | 7<<0); /* dclkdiv → sysclk/16; bclkdiv → sysclk/8 */
+	wr(0x1a, reg1a = reg1a | 1<<0); /* enable pll */
+
+	rate = s;
+
+	return 0;
+}
+
+static void
+reset(void)
+{
+	int i;
+
+	for(i = 0; i < Nout; i++){
+		out[i].vol[0] = -1;
+		out[i].vol[1] = -1;
+	}
+
+	toggle(out+Dac, 0);
+	wr(0x1c, 1<<7 | 1<<4 | 1<<3 | 1<<2); /* Vmid/r bias; Vgs/r on; Vmid soft start */
+	wr(0x19, 0<<7); /* Vmid off, Vref off */
+	sleep(500);
+	wr(0x0f, 0); /* reset registers to default */
+
+	setrate(rate);
+	set3d(⅓d);
+
+	wr(0x07, 1<<6 | 2); /* master mode; i²s, 16-bit words */
+
+	wr(0x17, 1<<8 | 3<<6 | 0<<1); /* thermal shutdown on; avdd=3.3v; slow clock on */
+
+	wr(0x06, 1<<3 | 1<<2); /* ramp up DAC volume slowly */
+	wr(0x2f, 3<<2); /* output mixer on */
+	wr(0x22, 1<<8); /* L DAC to mixer */
+	wr(0x25, 1<<8); /* R DAC to mixer */
+
+	wr(0x17, 1<<8 | 3<<6 | 1<<0); /* thermal shutdown on; avdd=3.3v; slow clock on */
+	wr(0x1c, 1<<7 | 1<<4 | 1<<3 | 1<<2); /* Vmid/r bias; Vgs/r on; Vmid soft start */
+	wr(0x19, 1<<7); /* start Vmid (playback) */
+	sleep(650);
+	wr(0x1c, 1<<3); /* done with anti-pop */
+	wr(0x19, 1<<7 | 1<<6); /* Vref on */
+
+	wr(0x09, 1<<6); /* adclrc → gpio (for jack detect output) */
+	wr(0x30, 3<<4 | 2<<2 | 1<<1); /* JD2 jack detect in; Tsense on */
+	wr(0x1b, 1<<3); /* HP_[LR] responsive to jack detect */
+	wr(0x18, 1<<6); /* HP switch on; high = HP */
+
+	/* turn on all outputs */
+	toggle(out+Hp, 1);
+	toggle(out+Spk, 1);
+	toggle(out+Dac, 1);
+
+	/* sensible defaults */
+	setvol(out+Spk, 100, 100);
+	setvol(out+Hp, 75, 75);
+	setvol(out+Dac, 80, 80);
+
+	/*
+	 * Jack detect becomes extremely unstable when playing on spk and the
+	 * volume is very high - DAC start to switch back and forth between two
+	 * outputs.  Solve this by always attenuating by -6dB and somewhat limiting
+	 * the volume on DAC ("master") - to 0xf9 instead of 0xff (max).
+	 */
+	wr(0x05, 1<<7 | 0<<3); /* unmute DAC */
+}
+
+static void
+fsread(Req *r)
+{
+	char msg[256], *s, *e;
+	Out *o;
+	int i;
+
+	s = msg;
+	e = msg+sizeof(msg);
+	*s = 0;
+	if(r->fid->file->aux == (void*)Ctl){
+		for(i = 0, o = out; i < Nout; i++, o++)
+			s = seprint(s, e, "%s %s\n", o->name, o->on ? "on" : "off");
+	}else if(r->fid->file->aux == (void*)Vol){
+		for(i = 0, o = out; i < Nout; i++, o++)
+			s = seprint(s, e, "%s %d %d\n", o->name, o->vol[0], o->vol[1]);
+		s = seprint(s, e, "speed %d\n", rate);
+		seprint(s, e, "3d %d\n", ⅓d);
+	}
+
+	readstr(r, msg);
+	respond(r, nil);
+}
+
+static int
+setoradd(int x, char *s)
+{
+	int d;
+
+	d = atoi(s);
+	if(*s == '+' || *s == '-')
+		return x + d;
+
+	return d;
+}
+
+static void
+fswrite(Req *r)
+{
+	int nf, on, i, vl, vr;
+	char msg[256], *f[4];
+	Out *o;
+
+	snprint(msg, sizeof(msg), "%.*s",
+		utfnlen((char*)r->ifcall.data, r->ifcall.count), (char*)r->ifcall.data);
+	nf = tokenize(msg, f, nelem(f));
+	if(nf == 1 && strcmp(f[0], "reset") == 0){
+		reset();
+		goto Done;
+	}else if(nf == 2 && strcmp(f[0], "speed") == 0){
+		if(setrate(atoi(f[1])) != 0){
+			respond(r, "not supported");
+			return;
+		}
+		goto Done;
+	}else if(nf == 2 && strcmp(f[0], "3d") == 0){
+		set3d(atoi(f[1]));
+		goto Done;
+	}
+	if(nf < 2){
+Emsg:
+		respond(r, "invalid ctl message");
+		return;
+	}
+
+	for(i = 0, o = out; i < Nout && strcmp(f[0], o->name) != 0; i++, o++)
+		;
+	if(i >= Nout)
+		goto Emsg;
+
+	if(r->fid->file->aux == (void*)Ctl){
+		if(nf != 2)
+			goto Emsg;
+		if(strcmp(f[1], "on") == 0)
+			on = 1;
+		else if(strcmp(f[1], "off") == 0)
+			on = 0;
+		else if(strcmp(f[1], "toggle") == 0)
+			on = !o->on;
+		else
+			goto Emsg;
+		toggle(o, on);
+	}else if(r->fid->file->aux == (void*)Vol){
+		vl = setoradd(o->vol[0], f[1]);
+		vr = setoradd(o->vol[1], nf < 3 ? f[1] : f[2]);
+		setvol(o, vl, vr);
+	}
+
+Done:
+	r->ofcall.count = r->ifcall.count;
+	respond(r, nil);
+}
+
+static Srv fs = {
+	.read = fsread,
+	.write = fswrite,
+};
+
+static void
+usage(void)
+{
+	fprint(2, "usage: %s [-1] [-D] [-m /dev] [-s service]\n", argv0);
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	char *mtpt, *srv;
+	int ctl, oneshot;
+
+	mtpt = "/dev";
+	srv = nil;
+	oneshot = 0;
+	ARGBEGIN{
+	case '1':
+		oneshot = 1;
+		break;
+	case 'D':
+		chatty9p = 1;
+		break;
+	case 'm':
+		mtpt = EARGF(usage());
+		break;
+	case 's':
+		srv = EARGF(usage());
+		break;
+	default:
+		usage();
+	}ARGEND
+
+	if((data = open("#J/i2c3/i2c.1a.data", OWRITE)) < 0)
+		sysfatal("i2c data: %r");
+	if((ctl = open("#J/i2c3/i2c.1a.ctl", OWRITE)) < 0)
+		sysfatal("i2c ctl: %r");
+	fprint(ctl, "subaddress 1\n");
+	fprint(ctl, "size %d\n", 0x38<<1);
+	close(ctl);
+
+	reset();
+
+	if(oneshot)
+		exits(nil);
+
+	fs.tree = alloctree(uid, uid, DMDIR|0555, nil);
+	createfile(fs.tree->root, "audioctl", uid, 0666, (void*)Ctl);
+	createfile(fs.tree->root, "volume", uid, 0666, (void*)Vol);
+	/* have to mount -b to shadow sai's useless files */
+	postmountsrv(&fs, srv, mtpt, MBEFORE);
+
+	exits(nil);
+}