ALSA: azt3328: add custom AC97 semi-emulation use standard ALSA AC97 layer

Make use of the very flexible ALSA ac97 layer (hooks for custom I/O!)
on this weird AC97 copycat hardware,
via semi-extended I/O translation/emulation.

Some 5kB binary/loaded size saved (well... additional huge AC97 module
penalty not factored in, of course ;-P).
Given that the driver previously had 20kB that's not bad,
but the much more important thing is to have AC97 layer stress-tested
with a thoroughly weird AC97 copycat (or, simply put, if it were not for
this AC97 test aspect, this effort would merely have been a nut job ;).

Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 402 insertions, 48 deletions

diff --git a/sound/pci/azt3328.c b/sound/pci/azt3328.c
index 6117595fc075..bb84bb68a776 100644
--- a/sound/pci/azt3328.c
+++ b/sound/pci/azt3328.c
@@ -1,6 +1,5 @@
-/*
- *  azt3328.c - driver for Aztech AZF3328 based soundcards (e.g. PCI168).
- *  Copyright (C) 2002, 2005 - 2010 by Andreas Mohr <andi AT lisas.de>
+/*  azt3328.c - driver for Aztech AZF3328 based soundcards (e.g. PCI168).
+ *  Copyright (C) 2002, 2005 - 2011 by Andreas Mohr <andi AT lisas.de>
  *
  *  Framework borrowed from Bart Hartgers's als4000.c.
  *  Driver developed on PCI168 AP(W) version (PCI rev. 10, subsystem ID 1801),
@@ -66,6 +65,13 @@
  *    addresses illegally. So far unfortunately it looks like the very flexible
  *    ALSA AC97 support is still not enough to easily compensate for such a
  *    grave layout violation despite all tweaks and quirks mechanisms it offers.
+ *    Well, not quite: now ac97 layer is much improved (bus-specific ops!),
+ *    thus I was able to implement support - it's actually working quite well.
+ *    An interesting item might be Aztech AMR 2800-W, since it's an AC97
+ *    modem card which might reveal the Aztech-specific codec ID which
+ *    we might want to pretend, too. Dito PCI168's brother, PCI368,
+ *    where the advertising datasheet says it's AC97-based and has a
+ *    Digital Enhanced Game Port.
  *  - builtin genuine OPL3 - verified to work fine, 20080506
  *  - full duplex 16bit playback/record at independent sampling rate
  *  - MPU401 (+ legacy address support, claimed by one official spec sheet)
@@ -189,6 +195,16 @@
 #include <sound/mpu401.h>
 #include <sound/opl3.h>
 #include <sound/initval.h>
+/*
+ * Config switch, to use ALSA's AC97 layer instead of old custom mixer crap.
+ * If the AC97 compatibility parts we needed to implement locally turn out
+ * to work nicely, then remove the old implementation eventually.
+ */
+#define AZF_USE_AC97_LAYER 1
+
+#ifdef AZF_USE_AC97_LAYER
+#include <sound/ac97_codec.h>
+#endif
 #include "azt3328.h"
 
 MODULE_AUTHOR("Andreas Mohr <andi AT lisas.de>");
@@ -328,6 +344,10 @@ struct snd_azf3328 {
         /* playback, recording and I2S out codecs */
         struct snd_azf3328_codec_data codecs[3];
 
+#ifdef AZF_USE_AC97_LAYER
+        struct snd_ac97 *ac97;
+#endif
+
         struct snd_card *card;
         struct snd_rawmidi *rmidi;
 
@@ -506,7 +526,7 @@ snd_azf3328_mixer_inw(const struct snd_azf3328 *chip, unsigned reg)
 #define AZF_MUTE_BIT 0x80
 
 static bool
-snd_azf3328_mixer_set_mute(const struct snd_azf3328 *chip,
+snd_azf3328_mixer_mute_control(const struct snd_azf3328 *chip,
                            unsigned reg, bool do_mute
 )
 {
@@ -521,6 +541,323 @@ snd_azf3328_mixer_set_mute(const struct snd_azf3328 *chip,
         return (do_mute) ? !updated : updated;
 }
 
+static inline bool
+snd_azf3328_mixer_mute_control_master(const struct snd_azf3328 *chip,
+                           bool do_mute
+)
+{
+        return snd_azf3328_mixer_mute_control(
+                chip,
+                IDX_MIXER_PLAY_MASTER,
+                do_mute
+        );
+}
+
+static inline bool
+snd_azf3328_mixer_mute_control_pcm(const struct snd_azf3328 *chip,
+                           bool do_mute
+)
+{
+        return snd_azf3328_mixer_mute_control(
+                chip,
+                IDX_MIXER_WAVEOUT,
+                do_mute
+        );
+}
+
+static inline void
+snd_azf3328_mixer_reset(const struct snd_azf3328 *chip)
+{
+        /* reset (close) mixer:
+         * first mute master volume, then reset
+         */
+        snd_azf3328_mixer_mute_control_master(chip, 1);
+        snd_azf3328_mixer_outw(chip, IDX_MIXER_RESET, 0x0000);
+}
+
+#ifdef AZF_USE_AC97_LAYER
+
+static inline void
+snd_azf3328_mixer_ac97_map_unsupported(unsigned short reg, const char *mode)
+{
+        /* need to add some more or less clever emulation? */
+        printk(KERN_WARNING
+                "azt3328: missing %s emulation for AC97 register 0x%02x!\n",
+                mode, reg);
+}
+
+/*
+ * Need to have _special_ AC97 mixer hardware register index mapper,
+ * to compensate for the issue of a rather AC97-incompatible hardware layout.
+ */
+#define AZF_REG_MASK 0x3f
+#define AZF_AC97_REG_UNSUPPORTED 0x8000
+#define AZF_AC97_REG_REAL_IO_READ 0x4000
+#define AZF_AC97_REG_REAL_IO_WRITE 0x2000
+#define AZF_AC97_REG_REAL_IO_RW \
+        (AZF_AC97_REG_REAL_IO_READ | AZF_AC97_REG_REAL_IO_WRITE)
+#define AZF_AC97_REG_EMU_IO_READ 0x0400
+#define AZF_AC97_REG_EMU_IO_WRITE 0x0200
+#define AZF_AC97_REG_EMU_IO_RW \
+        (AZF_AC97_REG_EMU_IO_READ | AZF_AC97_REG_EMU_IO_WRITE)
+static unsigned short
+snd_azf3328_mixer_ac97_map_reg_idx(unsigned short reg)
+{
+        static const struct {
+                unsigned short azf_reg;
+        } azf_reg_mapper[] = {
+                /* Especially when taking into consideration
+                 * mono/stereo-based sequence of azf vs. AC97 control series,
+                 * it's quite obvious that azf simply got rid
+                 * of the AC97_HEADPHONE control at its intended offset,
+                 * thus shifted _all_ controls by one,
+                 * and _then_ simply added it as an FMSYNTH control at the end,
+                 * to make up for the offset.
+                 * This means we'll have to translate indices here as
+                 * needed and then do some tiny AC97 patch action
+                 * (snd_ac97_rename_vol_ctl() etc.) - that's it.
+                 */
+                { /* AC97_RESET */ IDX_MIXER_RESET
+                        | AZF_AC97_REG_REAL_IO_WRITE
+                        | AZF_AC97_REG_EMU_IO_READ },
+                { /* AC97_MASTER */ IDX_MIXER_PLAY_MASTER },
+                 /* note large shift: AC97_HEADPHONE to IDX_MIXER_FMSYNTH! */
+                { /* AC97_HEADPHONE */ IDX_MIXER_FMSYNTH },
+                { /* AC97_MASTER_MONO */ IDX_MIXER_MODEMOUT },
+                { /* AC97_MASTER_TONE */ IDX_MIXER_BASSTREBLE },
+                { /* AC97_PC_BEEP */ IDX_MIXER_PCBEEP },
+                { /* AC97_PHONE */ IDX_MIXER_MODEMIN },
+                { /* AC97_MIC */ IDX_MIXER_MIC },
+                { /* AC97_LINE */ IDX_MIXER_LINEIN },
+                { /* AC97_CD */ IDX_MIXER_CDAUDIO },
+                { /* AC97_VIDEO */ IDX_MIXER_VIDEO },
+                { /* AC97_AUX */ IDX_MIXER_AUX },
+                { /* AC97_PCM */ IDX_MIXER_WAVEOUT },
+                { /* AC97_REC_SEL */ IDX_MIXER_REC_SELECT },
+                { /* AC97_REC_GAIN */ IDX_MIXER_REC_VOLUME },
+                { /* AC97_REC_GAIN_MIC */ AZF_AC97_REG_EMU_IO_RW },
+                { /* AC97_GENERAL_PURPOSE */ IDX_MIXER_ADVCTL2 },
+                { /* AC97_3D_CONTROL */ IDX_MIXER_ADVCTL1 },
+        };
+
+        unsigned short reg_azf = AZF_AC97_REG_UNSUPPORTED;
+
+        /* azf3328 supports the low-numbered and low-spec:ed range
+           of AC97 regs only */
+        if (reg <= AC97_3D_CONTROL) {
+                unsigned short reg_idx = reg / 2;
+                reg_azf = azf_reg_mapper[reg_idx].azf_reg;
+                /* a translation-only entry means it's real read/write: */
+                if (!(reg_azf & ~AZF_REG_MASK))
+                        reg_azf |= AZF_AC97_REG_REAL_IO_RW;
+        } else {
+                switch (reg) {
+                case AC97_POWERDOWN:
+                        reg_azf = AZF_AC97_REG_EMU_IO_RW;
+                        break;
+                case AC97_EXTENDED_ID:
+                        reg_azf = AZF_AC97_REG_EMU_IO_READ;
+                        break;
+                case AC97_EXTENDED_STATUS:
+                        /* I don't know what the h*ll AC97 layer
+                         * would consult this _extended_ register for
+                         * given a base-AC97-advertised card,
+                         * but let's just emulate it anyway :-P
+                         */
+                        reg_azf = AZF_AC97_REG_EMU_IO_RW;
+                        break;
+                case AC97_VENDOR_ID1:
+                case AC97_VENDOR_ID2:
+                        reg_azf = AZF_AC97_REG_EMU_IO_READ;
+                        break;
+                }
+        }
+        return reg_azf;
+}
+
+static const unsigned short
+azf_emulated_ac97_caps =
+        AC97_BC_DEDICATED_MIC |
+        AC97_BC_BASS_TREBLE |
+        /* Headphone is an FM Synth control here */
+        AC97_BC_HEADPHONE |
+        /* no AC97_BC_LOUDNESS! */
+        /* mask 0x7c00 is
+           vendor-specific 3D enhancement
+           vendor indicator.
+           Since there actually _is_ an
+           entry for Aztech Labs
+           (13), make damn sure
+           to indicate it. */
+        (13 << 10);
+
+static const unsigned short
+azf_emulated_ac97_powerdown =
+        /* pretend everything to be active */
+                AC97_PD_ADC_STATUS |
+                AC97_PD_DAC_STATUS |
+                AC97_PD_MIXER_STATUS |
+                AC97_PD_VREF_STATUS;
+
+/*
+ * Emulated, _inofficial_ vendor ID
+ * (there might be some devices such as the MR 2800-W
+ * which could reveal the real Aztech AC97 ID).
+ * We choose to use "AZT" prefix, and then use 1 to indicate PCI168
+ * (better don't use 0x68 since there's a PCI368 as well).
+ */
+static const unsigned int
+azf_emulated_ac97_vendor_id = 0x415a5401;
+
+static unsigned short
+snd_azf3328_mixer_ac97_read(struct snd_ac97 *ac97, unsigned short reg_ac97)
+{
+        const struct snd_azf3328 *chip = ac97->private_data;
+        unsigned short reg_azf = snd_azf3328_mixer_ac97_map_reg_idx(reg_ac97);
+        unsigned short reg_val = 0;
+        bool unsupported = 0;
+
+        snd_azf3328_dbgmixer(
+                "snd_azf3328_mixer_ac97_read reg_ac97 %u\n",
+                        reg_ac97
+        );
+        if (reg_azf & AZF_AC97_REG_UNSUPPORTED)
+                unsupported = 1;
+        else {
+                if (reg_azf & AZF_AC97_REG_REAL_IO_READ)
+                        reg_val = snd_azf3328_mixer_inw(chip,
+                                                reg_azf & AZF_REG_MASK);
+                else {
+                        /*
+                         * Proceed with dummy I/O read,
+                         * to ensure compatible timing where this may matter.
+                         * (ALSA AC97 layer usually doesn't call I/O functions
+                         * due to intelligent I/O caching anyway)
+                         * Choose a mixer register that's thoroughly unrelated
+                         * to common audio (try to minimize distortion).
+                         */
+                        snd_azf3328_mixer_inw(chip, IDX_MIXER_SOMETHING30H);
+                }
+
+                if (reg_azf & AZF_AC97_REG_EMU_IO_READ) {
+                        switch (reg_ac97) {
+                        case AC97_RESET:
+                                reg_val |= azf_emulated_ac97_caps;
+                                break;
+                        case AC97_POWERDOWN:
+                                reg_val |= azf_emulated_ac97_powerdown;
+                                break;
+                        case AC97_EXTENDED_ID:
+                        case AC97_EXTENDED_STATUS:
+                                /* AFAICS we simply can't support anything: */
+                                reg_val |= 0;
+                                break;
+                        case AC97_VENDOR_ID1:
+                                reg_val = azf_emulated_ac97_vendor_id >> 16;
+                                break;
+                        case AC97_VENDOR_ID2:
+                                reg_val = azf_emulated_ac97_vendor_id & 0xffff;
+                                break;
+                        default:
+                                unsupported = 1;
+                                break;
+                        }
+                }
+        }
+        if (unsupported)
+                snd_azf3328_mixer_ac97_map_unsupported(reg_ac97, "read");
+
+        return reg_val;
+}
+
+static void
+snd_azf3328_mixer_ac97_write(struct snd_ac97 *ac97,
+                     unsigned short reg_ac97, unsigned short val)
+{
+        const struct snd_azf3328 *chip = ac97->private_data;
+        unsigned short reg_azf = snd_azf3328_mixer_ac97_map_reg_idx(reg_ac97);
+        bool unsupported = 0;
+
+        snd_azf3328_dbgmixer(
+                "snd_azf3328_mixer_ac97_write reg_ac97 %u val %u\n",
+                        reg_ac97, val
+        );
+        if (reg_azf & AZF_AC97_REG_UNSUPPORTED)
+                unsupported = 1;
+        else {
+                if (reg_azf & AZF_AC97_REG_REAL_IO_WRITE)
+                        snd_azf3328_mixer_outw(
+                                chip,
+                                reg_azf & AZF_REG_MASK,
+                                val
+                        );
+                else
+                if (reg_azf & AZF_AC97_REG_EMU_IO_WRITE) {
+                        switch (reg_ac97) {
+                        case AC97_REC_GAIN_MIC:
+                        case AC97_POWERDOWN:
+                        case AC97_EXTENDED_STATUS:
+                                /*
+                                 * Silently swallow these writes.
+                                 * Since for most registers our card doesn't
+                                 * actually support a comparable feature,
+                                 * this is exactly what we should do here.
+                                 * The AC97 layer's I/O caching probably
+                                 * automatically takes care of all the rest...
+                                 * (remembers written values etc.)
+                                 */
+                                break;
+                        default:
+                                unsupported = 1;
+                                break;
+                        }
+                }
+        }
+        if (unsupported)
+                snd_azf3328_mixer_ac97_map_unsupported(reg_ac97, "write");
+}
+
+static int __devinit
+snd_azf3328_mixer_new(struct snd_azf3328 *chip)
+{
+        struct snd_ac97_bus *bus;
+        struct snd_ac97_template ac97;
+        static struct snd_ac97_bus_ops ops = {
+                .write = snd_azf3328_mixer_ac97_write,
+                .read = snd_azf3328_mixer_ac97_read,
+        };
+        int rc;
+
+        memset(&ac97, 0, sizeof(ac97));
+        ac97.scaps = AC97_SCAP_SKIP_MODEM
+                        | AC97_SCAP_AUDIO /* we support audio! */
+                        | AC97_SCAP_NO_SPDIF;
+        ac97.private_data = chip;
+        ac97.pci = chip->pci;
+
+        /*
+         * ALSA's AC97 layer has terrible init crackling issues,
+         * unfortunately, and since it makes use of AC97_RESET,
+         * there's no use trying to mute Master Playback proactively.
+         */
+
+        rc = snd_ac97_bus(chip->card, 0, &ops, NULL, &bus);
+        if (!rc)
+                rc = snd_ac97_mixer(bus, &ac97, &chip->ac97);
+                /*
+                 * Make sure to complain loudly in case of AC97 init failure,
+                 * since failure may happen quite often,
+                 * due to this card being a very quirky AC97 "lookalike".
+                 */
+        if (rc)
+                printk(KERN_ERR "azt3328: AC97 init failed, err %d!\n", rc);
+
+        /* If we return an error here, then snd_card_free() should
+         * free up any ac97 codecs that got created, as well as the bus.
+         */
+        return rc;
+}
+#else /* AZF_USE_AC97_LAYER */
 static void
 snd_azf3328_mixer_write_volume_gradually(const struct snd_azf3328 *chip,
                                          unsigned reg,
@@ -945,6 +1282,7 @@ snd_azf3328_mixer_new(struct snd_azf3328 *chip)
         snd_azf3328_dbgcallleave();
         return 0;
 }
+#endif /* AZF_USE_AC97_LAYER */
 
 static int
 snd_azf3328_hw_params(struct snd_pcm_substream *substream,
@@ -1239,8 +1577,8 @@ snd_azf3328_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
                 if (is_main_mixer_playback_codec) {
                         /* mute WaveOut (avoid clicking during setup) */
                         previously_muted =
-                                snd_azf3328_mixer_set_mute(
-                                                chip, IDX_MIXER_WAVEOUT, 1
+                                snd_azf3328_mixer_mute_control_pcm(
+                                                chip, 1
                                 );
                 }
 
@@ -1296,8 +1634,8 @@ snd_azf3328_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
                 if (is_main_mixer_playback_codec) {
                         /* now unmute WaveOut */
                         if (!previously_muted)
-                                snd_azf3328_mixer_set_mute(
-                                                chip, IDX_MIXER_WAVEOUT, 0
+                                snd_azf3328_mixer_mute_control_pcm(
+                                                chip, 0
                                 );
                 }
 
@@ -1321,8 +1659,8 @@ snd_azf3328_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
                 if (is_main_mixer_playback_codec) {
                         /* mute WaveOut (avoid clicking during setup) */
                         previously_muted =
-                                snd_azf3328_mixer_set_mute(
-                                                chip, IDX_MIXER_WAVEOUT, 1
+                                snd_azf3328_mixer_mute_control_pcm(
+                                                chip, 1
                                 );
                 }
 
@@ -1347,8 +1685,8 @@ snd_azf3328_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
                 if (is_main_mixer_playback_codec) {
                         /* now unmute WaveOut */
                         if (!previously_muted)
-                                snd_azf3328_mixer_set_mute(
-                                                chip, IDX_MIXER_WAVEOUT, 0
+                                snd_azf3328_mixer_mute_control_pcm(
+                                                chip, 0
                                 );
                 }
 
@@ -2056,11 +2394,7 @@ snd_azf3328_free(struct snd_azf3328 *chip)
         if (chip->irq < 0)
                 goto __end_hw;
 
-        /* reset (close) mixer:
-         * first mute master volume, then reset
-         */
-        snd_azf3328_mixer_set_mute(chip, IDX_MIXER_PLAY_MASTER, 1);
-        snd_azf3328_mixer_outw(chip, IDX_MIXER_RESET, 0x0000);
+        snd_azf3328_mixer_reset(chip);
 
         snd_azf3328_timer_stop(chip->timer);
         snd_azf3328_gameport_free(chip);
@@ -2413,6 +2747,55 @@ snd_azf3328_suspend_regs(unsigned long io_addr, unsigned count, u32 *saved_regs)
         }
 }
 
+static inline void
+snd_azf3328_resume_regs(const u32 *saved_regs,
+                        unsigned long io_addr,
+                        unsigned count
+)
+{
+        unsigned reg;
+
+        for (reg = 0; reg < count; ++reg) {
+                outl(*saved_regs, io_addr);
+                snd_azf3328_dbgpm("resume: io 0x%04lx: 0x%08x --> 0x%08x\n",
+                        io_addr, *saved_regs, inl(io_addr));
+                ++saved_regs;
+                io_addr += sizeof(*saved_regs);
+        }
+}
+
+static inline void
+snd_azf3328_suspend_ac97(struct snd_azf3328 *chip)
+{
+#ifdef AZF_USE_AC97_LAYER
+        snd_ac97_suspend(chip->ac97);
+#else
+        snd_azf3328_suspend_regs(chip->mixer_io,
+                ARRAY_SIZE(chip->saved_regs_mixer), chip->saved_regs_mixer);
+
+        /* make sure to disable master volume etc. to prevent looping sound */
+        snd_azf3328_mixer_mute_control_master(chip, 1);
+        snd_azf3328_mixer_mute_control_pcm(chip, 1);
+#endif /* AZF_USE_AC97_LAYER */
+}
+
+static inline void
+snd_azf3328_resume_ac97(const struct snd_azf3328 *chip)
+{
+#ifdef AZF_USE_AC97_LAYER
+        snd_ac97_resume(chip->ac97);
+#else
+        snd_azf3328_resume_regs(chip->saved_regs_mixer, chip->mixer_io,
+                                        ARRAY_SIZE(chip->saved_regs_mixer));
+
+        /* unfortunately with 32bit transfers, IDX_MIXER_PLAY_MASTER (0x02)
+           and IDX_MIXER_RESET (offset 0x00) get touched at the same time,
+           resulting in a mixer reset condition persisting until _after_
+           master vol was restored. Thus master vol needs an extra restore. */
+        outw(((u16 *)chip->saved_regs_mixer)[1], chip->mixer_io + 2);
+#endif /* AZF_USE_AC97_LAYER */
+}
+
 static int
 snd_azf3328_suspend(struct pci_dev *pci, pm_message_t state)
 {
@@ -2426,12 +2809,7 @@ snd_azf3328_suspend(struct pci_dev *pci, pm_message_t state)
         snd_pcm_suspend_all(chip->pcm[AZF_CODEC_PLAYBACK]);
         snd_pcm_suspend_all(chip->pcm[AZF_CODEC_I2S_OUT]);
 
-        snd_azf3328_suspend_regs(chip->mixer_io,
-                ARRAY_SIZE(chip->saved_regs_mixer), chip->saved_regs_mixer);
-
-        /* make sure to disable master volume etc. to prevent looping sound */
-        snd_azf3328_mixer_set_mute(chip, IDX_MIXER_PLAY_MASTER, 1);
-        snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 1);
+        snd_azf3328_suspend_ac97(chip);
 
         snd_azf3328_suspend_regs(chip->ctrl_io,
                 ARRAY_SIZE(chip->saved_regs_ctrl), chip->saved_regs_ctrl);
@@ -2453,23 +2831,6 @@ snd_azf3328_suspend(struct pci_dev *pci, pm_message_t state)
         return 0;
 }
 
-static inline void
-snd_azf3328_resume_regs(const u32 *saved_regs,
-                        unsigned long io_addr,
-                        unsigned count
-)
-{
-        unsigned reg;
-
-        for (reg = 0; reg < count; ++reg) {
-                outl(*saved_regs, io_addr);
-                snd_azf3328_dbgpm("resume: io 0x%04lx: 0x%08x --> 0x%08x\n",
-                        io_addr, *saved_regs, inl(io_addr));
-                ++saved_regs;
-                io_addr += sizeof(*saved_regs);
-        }
-}
-
 static int
 snd_azf3328_resume(struct pci_dev *pci)
 {
@@ -2493,14 +2854,7 @@ snd_azf3328_resume(struct pci_dev *pci)
         snd_azf3328_resume_regs(chip->saved_regs_opl3, chip->opl3_io,
                                         ARRAY_SIZE(chip->saved_regs_opl3));
 
-        snd_azf3328_resume_regs(chip->saved_regs_mixer, chip->mixer_io,
-                                        ARRAY_SIZE(chip->saved_regs_mixer));
-
-        /* unfortunately with 32bit transfers, IDX_MIXER_PLAY_MASTER (0x02)
-           and IDX_MIXER_RESET (offset 0x00) get touched at the same time,
-           resulting in a mixer reset condition persisting until _after_
-           master vol was restored. Thus master vol needs an extra restore. */
-        outw(((u16 *)chip->saved_regs_mixer)[1], chip->mixer_io + 2);
+        snd_azf3328_resume_ac97(chip);
 
         snd_azf3328_resume_regs(chip->saved_regs_ctrl, chip->ctrl_io,
                                         ARRAY_SIZE(chip->saved_regs_ctrl));