Fix awacs(4) audio on some iMac G3 models

This code affects iMac G3s with a slot-loading CD drive (from late
1999 to 2001, after the older tray-loading iMac G3s, and before the
iMac G4s).  Detect such iMacs by their model string (PowerMac2,1 or
PowerMac2,2 or PowerMac4,1), and configure their headphones and
internal speakers in a different way.  These iMacs have 3 places to
connect headphones (2 on front, 1 on right side).  They also have no
audio connection to the CD drive, so turn off the noisy CD input.

From evan (dot) jss (at) protonmail (dot) ch; I edited the code to get
the model string.

diff --git a/sys/arch/macppc/dev/awacs.c b/sys/arch/macppc/dev/awacs.c
index 335dc26..3791ee2 100644 (file)
--- a/sys/arch/macppc/dev/awacs.c
+++ b/sys/arch/macppc/dev/awacs.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: awacs.c,v 1.40 2022/10/26 20:19:07 kn Exp $   */
+/*     $OpenBSD: awacs.c,v 1.41 2024/03/03 02:40:10 gkoehler Exp $     */
 /*     $NetBSD: awacs.c,v 1.4 2001/02/26 21:07:51 wiz Exp $    */
 
 /*-
@@ -70,6 +70,9 @@ struct awacs_softc {
        u_int sc_record_source;         /* recording source mask */
        u_int sc_output_mask;           /* output source mask */
 
+       int sc_awacs_hardware;
+       int sc_awacs_headphone_mask;
+
        char *sc_reg;
        u_int sc_codecctl0;
        u_int sc_codecctl1;
@@ -195,6 +198,11 @@ const struct audio_hw_if awacs_hw_if = {
 /* cc1 */
 #define AWACS_MUTE_SPEAKER     0x00000080
 #define AWACS_MUTE_HEADPHONE   0x00000200
+/*
+ * iMacs that use this driver have a speaker amp power down feature,
+ * triggered by this bit in cc1.
+ */
+#define AWACS_MUTE_SPEAKER_IMAC        0x00000800
 
 const struct awacs_speed_tab {
        int rate;
@@ -210,6 +218,25 @@ const struct awacs_speed_tab {
        { 44100, AWACS_RATE_44100 },
 };
 
+/* add hardware as needed */
+#define HW_IS_OTHER 0
+/* iMac (Late 1999) */
+#define HW_IS_IMAC1 1
+/* iMac (Summer 2000) and iMac (Early 2001, Summer 2001) */
+#define HW_IS_IMAC2 2
+
+/* Codecs status headphones mask */
+
+/* headphone connector on back */
+#define AWACS_STATUS_HP_CONN 8
+
+/* right connector on front */
+#define AWACS_STATUS_HP_RCONN_IMAC 4
+/* left connector on front */
+#define AWACS_STATUS_HP_LCONN_IMAC 2
+/* connector on the right side */
+#define AWACS_STATUS_HP_SCONN_IMAC 1
+
 int
 awacs_match(struct device *parent, void *match, void *aux)
 {
@@ -243,6 +270,21 @@ awacs_attach(struct device *parent, struct device *self, void *aux)
        int cirq, oirq, iirq;
        int cirq_type, oirq_type, iirq_type;
 
+       if (!strcmp(hw_prod, "PowerMac2,1"))
+               sc->sc_awacs_hardware = HW_IS_IMAC1;
+       else if (!strcmp(hw_prod, "PowerMac2,2") ||
+           !strcmp(hw_prod, "PowerMac4,1"))
+               sc->sc_awacs_hardware = HW_IS_IMAC2;
+       else
+               sc->sc_awacs_hardware = HW_IS_OTHER;
+       /* set headphone mask */
+       if (sc->sc_awacs_hardware == HW_IS_IMAC1 ||
+           sc->sc_awacs_hardware == HW_IS_IMAC2)
+               sc->sc_awacs_headphone_mask = AWACS_STATUS_HP_LCONN_IMAC |
+                   AWACS_STATUS_HP_RCONN_IMAC | AWACS_STATUS_HP_SCONN_IMAC;
+       else
+               sc->sc_awacs_headphone_mask = AWACS_STATUS_HP_CONN;
+       
        ca->ca_reg[0] += ca->ca_baseaddr;
        ca->ca_reg[2] += ca->ca_baseaddr;
        ca->ca_reg[4] += ca->ca_baseaddr;
@@ -289,7 +331,10 @@ awacs_attach(struct device *parent, struct device *self, void *aux)
        sc->sc_codecctl2 = AWACS_CODEC_ADDR2 | AWACS_CODEC_EMSEL0;
        sc->sc_codecctl4 = AWACS_CODEC_ADDR4 | AWACS_CODEC_EMSEL0;
 
-       sc->sc_codecctl0 |= AWACS_INPUT_CD | AWACS_DEFAULT_CD_GAIN;
+       /* don't set CD in on iMacs, or else the outputs will be very noisy */
+       if (sc->sc_awacs_hardware != HW_IS_IMAC1 &&
+           sc->sc_awacs_hardware != HW_IS_IMAC2)
+               sc->sc_codecctl0 |= AWACS_INPUT_CD | AWACS_DEFAULT_CD_GAIN;
        awacs_write_codec(sc, sc->sc_codecctl0);
 
        /* Set initial volume[s] */
@@ -302,12 +347,25 @@ awacs_attach(struct device *parent, struct device *self, void *aux)
        awacs_write_codec(sc, sc->sc_codecctl1);
 
        /* check for headphone present */
-       if (awacs_read_reg(sc, AWACS_CODEC_STATUS) & 0x8) {
+       if (awacs_read_reg(sc, AWACS_CODEC_STATUS) &
+           sc->sc_awacs_headphone_mask) {
                /* default output to speakers */
                printf(" headphones");
                sc->sc_output_mask = 1 << 1;
-               sc->sc_codecctl1 &= ~AWACS_MUTE_HEADPHONE;
-               sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER;
+               /* front headphones on iMacs are wired to the speakers output */
+               if ((sc->sc_awacs_hardware != HW_IS_IMAC2 &&
+                   sc->sc_awacs_hardware != HW_IS_IMAC1) ||
+                   ((sc->sc_awacs_hardware == HW_IS_IMAC2 ||
+                   sc->sc_awacs_hardware == HW_IS_IMAC1) &&
+                   (awacs_read_reg(sc, AWACS_CODEC_STATUS) &
+                   AWACS_STATUS_HP_SCONN_IMAC))) {
+                       sc->sc_codecctl1 &= ~AWACS_MUTE_HEADPHONE;
+                       sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER;
+               }
+               if (sc->sc_awacs_hardware == HW_IS_IMAC1)
+                       sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER_IMAC;
+               else if (sc->sc_awacs_hardware == HW_IS_IMAC2)
+                       sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER_IMAC;
                awacs_write_codec(sc, sc->sc_codecctl1);
        } else {
                /* default output to speakers */
@@ -315,13 +373,19 @@ awacs_attach(struct device *parent, struct device *self, void *aux)
                sc->sc_output_mask = 1 << 0;
                sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER;
                sc->sc_codecctl1 |= AWACS_MUTE_HEADPHONE;
+               if (sc->sc_awacs_hardware == HW_IS_IMAC1)
+                       sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER_IMAC;
+               else if (sc->sc_awacs_hardware == HW_IS_IMAC2)
+                       sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER_IMAC;
                awacs_write_codec(sc, sc->sc_codecctl1);
        }
 
        /* default input from CD */
        sc->sc_record_source = 1 << 0;
        sc->sc_codecctl0 &= ~AWACS_INPUT_MASK;
-       sc->sc_codecctl0 |= AWACS_INPUT_CD;
+       if (sc->sc_awacs_hardware != HW_IS_IMAC1 &&
+           sc->sc_awacs_hardware != HW_IS_IMAC2)
+               sc->sc_codecctl0 |= AWACS_INPUT_CD;
        awacs_write_codec(sc, sc->sc_codecctl0);
 
        /* Enable interrupts and looping mode. */
@@ -372,17 +436,37 @@ awacs_intr(void *v)
                printf("status = %x\n", awacs_read_reg(sc, AWACS_CODEC_STATUS));
 #endif
 
-               if (awacs_read_reg(sc, AWACS_CODEC_STATUS) & 0x8) {
+               if (awacs_read_reg(sc, AWACS_CODEC_STATUS) &
+                   sc->sc_awacs_headphone_mask) {
                        /* default output to speakers */
                        sc->sc_output_mask = 1 << 1;
-                       sc->sc_codecctl1 &= ~AWACS_MUTE_HEADPHONE;
-                       sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER;
+                       /*
+                        * Front headphones on iMacs are wired to the
+                        * speakers output.
+                        */
+                       if ((sc->sc_awacs_hardware != HW_IS_IMAC2 &&
+                           sc->sc_awacs_hardware != HW_IS_IMAC1) ||
+                           ((sc->sc_awacs_hardware == HW_IS_IMAC2 ||
+                           sc->sc_awacs_hardware == HW_IS_IMAC1) &&
+                           (awacs_read_reg(sc, AWACS_CODEC_STATUS) &
+                           AWACS_STATUS_HP_SCONN_IMAC))) {
+                               sc->sc_codecctl1 &= ~AWACS_MUTE_HEADPHONE;
+                               sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER;
+                       }
+                       if (sc->sc_awacs_hardware == HW_IS_IMAC1)
+                               sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER_IMAC;
+                       else if (sc->sc_awacs_hardware == HW_IS_IMAC2)
+                               sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER_IMAC;
                        awacs_write_codec(sc, sc->sc_codecctl1);
                } else {
                        /* default output to speakers */
                        sc->sc_output_mask = 1 << 0;
                        sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER;
                        sc->sc_codecctl1 |= AWACS_MUTE_HEADPHONE;
+                       if (sc->sc_awacs_hardware == HW_IS_IMAC1)
+                               sc->sc_codecctl1 &= ~AWACS_MUTE_SPEAKER_IMAC;
+                       else if (sc->sc_awacs_hardware == HW_IS_IMAC2)
+                               sc->sc_codecctl1 |= AWACS_MUTE_SPEAKER_IMAC;
                        awacs_write_codec(sc, sc->sc_codecctl1);
                }
        }