ref: bdc1b187c45dbaeaa7dadce4d7999d9d550ec78f
dir: /sys/src/cmd/nusb/audio/audio.c/
#include <u.h> #include <libc.h> #include <fcall.h> #include <thread.h> #include <9p.h> #include "usb.h" typedef struct Audio Audio; struct Audio { Audio *next; int minfreq; int maxfreq; }; int audiodelay = 1764; /* 40 ms */ int audiofreq = 44100; int audiochan = 2; int audiores = 16; char user[] = "audio"; Dev *audiodev = nil; Ep *audioepin = nil; Ep *audioepout = nil; void parsedescr(Desc *dd) { Audio *a, **ap; uchar *b; int i; if(dd == nil || dd->iface == nil || dd->altc == nil) return; b = (uchar*)&dd->data; if(Subclass(dd->iface->csp) != 2 || b[1] != 0x24 || b[2] != 0x02) return; if(b[4] != audiochan) return; if(b[6] != audiores) return; ap = (Audio**)&dd->altc->aux; if(b[7] == 0){ a = mallocz(sizeof(*a), 1); a->minfreq = b[8] | b[9]<<8 | b[10]<<16; a->maxfreq = b[11] | b[12]<<8 | b[13]<<16; a->next = *ap; *ap = a; } else { for(i=0; i<b[7]; i++){ a = mallocz(sizeof(*a), 1); a->minfreq = b[8+3*i] | b[9+3*i]<<8 | b[10+3*i]<<16; a->maxfreq = a->minfreq; a->next = *ap; *ap = a; } } } Dev* setupep(Dev *d, Ep *e, int speed) { uchar b[4]; Audio *x; Altc *a; int i; for(i = 0; i < nelem(e->iface->altc); i++) if(a = e->iface->altc[i]) for(x = a->aux; x; x = x->next) if(speed >= x->minfreq && speed <= x->maxfreq) goto Foundaltc; werrstr("no altc found"); return nil; Foundaltc: if(usbcmd(d, Rh2d|Rstd|Riface, Rsetiface, i, e->iface->id, nil, 0) < 0){ werrstr("set altc: %r"); return nil; } b[0] = speed; b[1] = speed >> 8; b[2] = speed >> 16; if(usbcmd(d, Rh2d|Rclass|Rep, Rsetcur, 0x100, e->addr, b, 3) < 0) fprint(2, "warning: set freq: %r\n"); if((d = openep(d, e->id)) == nil){ werrstr("openep: %r"); return nil; } devctl(d, "pollival %d", a->interval); devctl(d, "samplesz %d", audiochan*audiores/8); devctl(d, "sampledelay %d", audiodelay); devctl(d, "hz %d", speed); if(e->dir == Ein) devctl(d, "name audioin"); else devctl(d, "name audio"); return d; } void fsread(Req *r) { char *msg; msg = smprint("master 100 100\nspeed %d\ndelay %d\n", audiofreq, audiodelay); readstr(r, msg); respond(r, nil); free(msg); } void fswrite(Req *r) { char msg[256], *f[4]; int nf, speed; snprint(msg, sizeof(msg), "%.*s", r->ifcall.count, r->ifcall.data); nf = tokenize(msg, f, nelem(f)); if(nf < 2){ respond(r, "invalid ctl message"); return; } if(strcmp(f[0], "speed") == 0){ Dev *d; speed = atoi(f[1]); Setup: if((d = setupep(audiodev, audioepout, speed)) == nil){ responderror(r); return; } closedev(d); if(audioepin != nil && audioepin != audioepout){ if(d = setupep(audiodev, audioepin, speed)) closedev(d); } audiofreq = speed; } else if(strcmp(f[0], "delay") == 0){ audiodelay = atoi(f[1]); speed = audiofreq; goto Setup; } r->ofcall.count = r->ifcall.count; respond(r, nil); } Srv fs = { .read = fsread, .write = fswrite, }; void usage(void) { fprint(2, "%s devid\n", argv0); exits("usage"); } void main(int argc, char *argv[]) { char buf[32]; Dev *d, *ed; Ep *e; int i; ARGBEGIN { case 'D': chatty9p++; break; case 'd': usbdebug++; break; } ARGEND; if(argc == 0) usage(); if((d = getdev(*argv)) == nil) sysfatal("getdev: %r"); audiodev = d; /* parse descriptors, mark valid altc */ for(i = 0; i < nelem(d->usb->ddesc); i++) parsedescr(d->usb->ddesc[i]); for(i = 0; i < nelem(d->usb->ep); i++){ e = d->usb->ep[i]; if(e != nil && e->type == Eiso && e->iface != nil && e->iface->csp == CSP(Claudio, 2, 0)){ switch(e->dir){ case Ein: if(audioepin != nil) continue; audioepin = e; break; case Eout: if(audioepout != nil) continue; audioepout = e; break; case Eboth: if(audioepin != nil && audioepout != nil) continue; if(audioepin == nil) audioepin = e; if(audioepout == nil) audioepout = e; break; } if((ed = setupep(audiodev, e, audiofreq)) == nil){ fprint(2, "setupep: %r\n"); if(e == audioepin) audioepin = nil; if(e == audioepout) audioepout = nil; continue; } closedev(ed); } } if(audioepout == nil) sysfatal("no endpoints found"); fs.tree = alloctree(user, "usb", DMDIR|0555, nil); createfile(fs.tree->root, "volume", user, 0666, nil); snprint(buf, sizeof buf, "%d.audio", audiodev->id); postsharesrv(&fs, nil, "usb", buf); exits(0); }