[ALSA] PCI168 snd-azt3328 Linux driver: another huge update

- figured out 'Digital(ly) Enhanced Game Port' functionality,
  implemented support for it (eliminating gameport polling overhead)
- removed optional joystick activation, gameport now enabled unconditionally,
  since we now support it via the PCI I/O space, not via conflict-prone
  legacy I/O (which I was thus able to DISABLE now)!
- fix playback bug (a muted wave output would get unmuted upon start of
  playback, of course this is not what we want, thus remember mute state)
- implement partial power management: when idle, lower clock rate and disable
  codec (reduced noise!), and disable gameport circuit when unused
- instantiate OPL3 timer, too
- much better implementation of snd_azf3328_mixer_write_volume_gradually()
- slightly optimized interrupt handling
- lots of cleanup

This time, I also found a way to verify proper OPL3 operation
via MIDI file playback (emulation via synth hardware).

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

1 files changed, 796 insertions, 396 deletions

diff --git a/sound/pci/azt3328.c b/sound/pci/azt3328.c
index 5f63af6b88a..b832333c302 100644
--- a/sound/pci/azt3328.c
+++ b/sound/pci/azt3328.c
@@ -1,6 +1,6 @@
 /*
  *  azt3328.c - driver for Aztech AZF3328 based soundcards (e.g. PCI168).
- *  Copyright (C) 2002, 2005, 2006, 2007 by Andreas Mohr <andi AT lisas.de>
+ *  Copyright (C) 2002, 2005 - 2008 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),
@@ -35,9 +35,20 @@
  *  (3 weeks' worth of evenings filled with driver work).
  *  (and no, I did NOT go the easy way: to pick up a SB PCI128 for 9 Euros)
  *
+ *  It is quite likely that the AZF3328 chip is the PCI cousin of the
+ *  AZF3318 ("azt1020 pnp", "MM Pro 16") ISA chip, given very similar specs.
+ *
  *  The AZF3328 chip (note: AZF3328, *not* AZT3328, that's just the driver name
- *  for compatibility reasons) has the following features:
+ *  for compatibility reasons) from Azfin (joint-venture of Aztech and Fincitec,
+ *  Fincitec acquired by National Semiconductor in 2002, together with the
+ *  Fincitec-related company ARSmikro) has the following features:
  *
+ *  - compatibility & compliance:
+ *    - Microsoft PC 97 ("PC 97 Hardware Design Guide",
+ *                       http://www.microsoft.com/whdc/archive/pcguides.mspx)
+ *    - Microsoft PC 98 Baseline Audio
+ *    - MPU401 UART
+ *    - Sound Blaster Emulation (DOS Box)
  *  - builtin AC97 conformant codec (SNR over 80dB)
  *    Note that "conformant" != "compliant"!! this chip's mixer register layout
  *    *differs* from the standard AC97 layout:
@@ -48,21 +59,28 @@
  *    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.
- *  - builtin genuine OPL3
+ *  - builtin genuine OPL3 - verified to work fine, 20080506
  *  - full duplex 16bit playback/record at independent sampling rate
- *  - MPU401 (+ legacy address support) FIXME: how to enable legacy addr??
+ *  - MPU401 (+ legacy address support, claimed by one official spec sheet)
+ *    FIXME: how to enable legacy addr??
  *  - game port (legacy address support)
- *  - builtin 3D enhancement (said to be YAMAHA Ymersion)
  *  - builtin DirectInput support, helps reduce CPU overhead (interrupt-driven
- *    features supported)
+ *    features supported). - See common term "Digital Enhanced Game Port"...
+ *    (probably DirectInput 3.0 spec - confirm)
+ *  - builtin 3D enhancement (said to be YAMAHA Ymersion)
  *  - built-in General DirectX timer having a 20 bits counter
  *    with 1us resolution (see below!)
- *  - I2S serial port for external DAC
+ *  - I2S serial output port for external DAC
  *  - supports 33MHz PCI spec 2.1, PCI power management 1.0, compliant with ACPI
  *  - supports hardware volume control
  *  - single chip low cost solution (128 pin QFP)
  *  - supports programmable Sub-vendor and Sub-system ID
  *    required for Microsoft's logo compliance (FIXME: where?)
+ *    At least the Trident 4D Wave DX has one bit somewhere
+ *    to enable writes to PCI subsystem VID registers, that should be it.
+ *    This might easily be in extended PCI reg space, since PCI168 also has
+ *    some custom data starting at 0x80. What kind of config settings
+ *    are located in our extended PCI space anyway??
  *  - PCI168 AP(W) card: power amplifier with 4 Watts/channel at 4 Ohms
  *
  *  Note that this driver now is actually *better* than the Windows driver,
@@ -74,6 +92,24 @@
  *  - "timidity -iAv -B2,8 -Os -EFreverb=0"
  *  - "pmidi -p 128:0 jazz.mid"
  *
+ *  OPL3 hardware playback testing, try something like:
+ *  cat /proc/asound/hwdep
+ *  and
+ *  aconnect -o
+ *  Then use
+ *  sbiload -Dhw:x,y --opl3 /usr/share/sounds/opl3/std.o3 ......./drums.o3
+ *  where x,y is the xx-yy number as given in hwdep.
+ *  Then try
+ *  pmidi -p a:b jazz.mid
+ *  where a:b is the client number plus 0 usually, as given by aconnect above.
+ *  Oh, and make sure to unmute the FM mixer control (doh!)
+ *  NOTE: power use during OPL3 playback is _VERY_ high (70W --> 90W!)
+ *  despite no CPU activity, possibly due to hindering ACPI idling somehow.
+ *  Shouldn't be a problem of the AZF3328 chip itself, I'd hope.
+ *  Higher PCM / FM mixer levels seem to conflict (causes crackling),
+ *  at least sometimes.   Maybe even use with hardware sequencer timer above :)
+ *  adplay/adplug-utils might soon offer hardware-based OPL3 playback, too.
+ *
  *  Certain PCI versions of this card are susceptible to DMA traffic underruns
  *  in some systems (resulting in sound crackling/clicking/popping),
  *  probably because they don't have a DMA FIFO buffer or so.
@@ -87,6 +123,8 @@
  *  better than a VIA, yet ironically I still get crackling, like many other
  *  people with the same chipset.
  *  Possible remedies:
+ *  - use speaker (amplifier) output instead of headphone output
+ *    (in case crackling is due to overloaded output clipping)
  *  - plug card into a different PCI slot, preferrably one that isn't shared
  *    too much (this helps a lot, but not completely!)
  *  - get rid of PCI VGA card, use AGP instead
@@ -94,18 +132,23 @@
  *  - fiddle with PCI latency settings (setpci -v -s BUSID latency_timer=XX)
  *    Not too helpful.
  *  - Disable ACPI/power management/"Auto Detect RAM/PCI Clk" in BIOS
- * 
+ *
  * BUGS
- *  - full-duplex might *still* be problematic, not fully tested recently
+ *  - full-duplex might *still* be problematic, however a recent test was fine
  *  - (non-bug) "Bass/Treble or 3D settings don't work" - they do get evaluated
  *    if you set PCM output switch to "pre 3D" instead of "post 3D".
  *    If this can't be set, then get a mixer application that Isn't Stupid (tm)
  *    (e.g. kmix, gamix) - unfortunately several are!!
- * 
+ *  - locking is not entirely clean, especially the audio stream activity
+ *    ints --> may be racy
+ *  - an _unconnected_ secondary joystick at the gameport will be reported
+ *    to be "active" (floating values, not precisely -1) due to the way we need
+ *    to read the Digital Enhanced Game Port. Not sure whether it is fixable.
+ *
  * TODO
  *  - test MPU401 MIDI playback etc.
- *  - add some power micro-management (disable various units of the card
- *    as long as they're unused). However this requires I/O ports which I
+ *  - add more power micro-management (disable various units of the card
+ *    as long as they're unused). However this requires more I/O ports which I
  *    haven't figured out yet and which thus might not even exist...
  *    The standard suspend/resume functionality could probably make use of
  *    some improvement, too...
@@ -113,6 +156,7 @@
  *  - figure out some cleverly evil scheme to possibly make ALSA AC97 code
  *    fully accept our quite incompatible ""AC97"" mixer and thus save some
  *    code (but I'm not too optimistic that doing this is possible at all)
+ *  - use MMIO (memory-mapped I/O)? Slightly faster access, e.g. for gameport.
  */
 
 #include <asm/io.h>
@@ -138,7 +182,7 @@ MODULE_LICENSE("GPL");
 MODULE_SUPPORTED_DEVICE("{{Aztech,AZF3328}}");
 
 #if defined(CONFIG_GAMEPORT) || (defined(MODULE) && defined(CONFIG_GAMEPORT_MODULE))
-#define SUPPORT_JOYSTICK 1
+#define SUPPORT_GAMEPORT 1
 #endif
 
 #define DEBUG_MISC	0
@@ -147,13 +191,14 @@ MODULE_SUPPORTED_DEVICE("{{Aztech,AZF3328}}");
 #define DEBUG_PLAY_REC	0
 #define DEBUG_IO	0
 #define DEBUG_TIMER	0
+#define DEBUG_GAME	0
 #define MIXER_TESTING	0
 
 #if DEBUG_MISC
 #define snd_azf3328_dbgmisc(format, args...) printk(KERN_ERR format, ##args)
 #else
 #define snd_azf3328_dbgmisc(format, args...)
-#endif		
+#endif
 
 #if DEBUG_CALLS
 #define snd_azf3328_dbgcalls(format, args...) printk(format, ##args)
@@ -163,25 +208,31 @@ MODULE_SUPPORTED_DEVICE("{{Aztech,AZF3328}}");
 #define snd_azf3328_dbgcalls(format, args...)
 #define snd_azf3328_dbgcallenter()
 #define snd_azf3328_dbgcallleave()
-#endif		
+#endif
 
 #if DEBUG_MIXER
 #define snd_azf3328_dbgmixer(format, args...) printk(format, ##args)
 #else
 #define snd_azf3328_dbgmixer(format, args...)
-#endif		
+#endif
 
 #if DEBUG_PLAY_REC
 #define snd_azf3328_dbgplay(format, args...) printk(KERN_ERR format, ##args)
 #else
 #define snd_azf3328_dbgplay(format, args...)
-#endif		
+#endif
 
 #if DEBUG_MISC
 #define snd_azf3328_dbgtimer(format, args...) printk(KERN_ERR format, ##args)
 #else
 #define snd_azf3328_dbgtimer(format, args...)
-#endif		
+#endif
+
+#if DEBUG_GAME
+#define snd_azf3328_dbggame(format, args...) printk(KERN_ERR format, ##args)
+#else
+#define snd_azf3328_dbggame(format, args...)
+#endif
 
 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;	/* Index 0-MAX */
 module_param_array(index, int, NULL, 0444);
@@ -195,39 +246,44 @@ static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;	/* Enable this card *
 module_param_array(enable, bool, NULL, 0444);
 MODULE_PARM_DESC(enable, "Enable AZF3328 soundcard.");
 
-#ifdef SUPPORT_JOYSTICK
-static int joystick[SNDRV_CARDS];
-module_param_array(joystick, bool, NULL, 0444);
-MODULE_PARM_DESC(joystick, "Enable joystick for AZF3328 soundcard.");
-#endif
-
 static int seqtimer_scaling = 128;
 module_param(seqtimer_scaling, int, 0444);
 MODULE_PARM_DESC(seqtimer_scaling, "Set 1024000Hz sequencer timer scale factor (lockup danger!). Default 128.");
 
+struct snd_azf3328_audio_stream {
+	struct snd_pcm_substream *substream;
+	int enabled;
+	int running;
+	unsigned long portbase;
+};
+
+enum snd_azf3328_stream_index {
+  AZF_PLAYBACK = 0,
+  AZF_CAPTURE = 1,
+};
+
 struct snd_azf3328 {
 	/* often-used fields towards beginning, then grouped */
-	unsigned long codec_port;
-	unsigned long io2_port;
-	unsigned long mpu_port;
-	unsigned long synth_port;
-	unsigned long mixer_port;
+
+	unsigned long codec_io; /* usually 0xb000, size 128 */
+	unsigned long game_io;  /* usually 0xb400, size 8 */
+	unsigned long mpu_io;   /* usually 0xb800, size 4 */
+	unsigned long opl3_io; /* usually 0xbc00, size 8 */
+	unsigned long mixer_io; /* usually 0xc000, size 64 */
 
 	spinlock_t reg_lock;
 
 	struct snd_timer *timer;
-	
+
 	struct snd_pcm *pcm;
-	struct snd_pcm_substream *playback_substream;
-	struct snd_pcm_substream *capture_substream;
-	unsigned int is_playing;
-	unsigned int is_recording;
+	struct snd_azf3328_audio_stream audio_stream[2];
 
 	struct snd_card *card;
 	struct snd_rawmidi *rmidi;
 
-#ifdef SUPPORT_JOYSTICK
+#ifdef SUPPORT_GAMEPORT
 	struct gameport *gameport;
+	int axes[4];
 #endif
 
 	struct pci_dev *pci;
@@ -236,10 +292,10 @@ struct snd_azf3328 {
 #ifdef CONFIG_PM
 	/* register value containers for power management
 	 * Note: not always full I/O range preserved (just like Win driver!) */
-	u16 saved_regs_codec [AZF_IO_SIZE_CODEC_PM / 2];
-	u16 saved_regs_io2   [AZF_IO_SIZE_IO2_PM / 2];
-	u16 saved_regs_mpu   [AZF_IO_SIZE_MPU_PM / 2];
-	u16 saved_regs_synth[AZF_IO_SIZE_SYNTH_PM / 2];
+	u16 saved_regs_codec[AZF_IO_SIZE_CODEC_PM / 2];
+	u16 saved_regs_game [AZF_IO_SIZE_GAME_PM / 2];
+	u16 saved_regs_mpu  [AZF_IO_SIZE_MPU_PM / 2];
+	u16 saved_regs_opl3 [AZF_IO_SIZE_OPL3_PM / 2];
 	u16 saved_regs_mixer[AZF_IO_SIZE_MIXER_PM / 2];
 #endif
 };
@@ -252,126 +308,181 @@ static const struct pci_device_id snd_azf3328_ids[] = {
 
 MODULE_DEVICE_TABLE(pci, snd_azf3328_ids);
 
+
+static int
+snd_azf3328_io_reg_setb(unsigned reg, u8 mask, int do_set)
+{
+	u8 prev = inb(reg), new;
+
+	new = (do_set) ? (prev|mask) : (prev & ~mask);
+	/* we need to always write the new value no matter whether it differs
+	 * or not, since some register bits don't indicate their setting */
+	outb(new, reg);
+	if (new != prev)
+		return 1;
+
+	return 0;
+}
+
+static int
+snd_azf3328_io_reg_setw(unsigned reg, u16 mask, int do_set)
+{
+	u16 prev = inw(reg), new;
+
+	new = (do_set) ? (prev|mask) : (prev & ~mask);
+	/* we need to always write the new value no matter whether it differs
+	 * or not, since some register bits don't indicate their setting */
+	outw(new, reg);
+	if (new != prev)
+		return 1;
+
+	return 0;
+}
+
 static inline void
-snd_azf3328_codec_outb(const struct snd_azf3328 *chip, int reg, u8 value)
+snd_azf3328_codec_outb(const struct snd_azf3328 *chip, unsigned reg, u8 value)
 {
-	outb(value, chip->codec_port + reg);
+	outb(value, chip->codec_io + reg);
 }
 
 static inline u8
-snd_azf3328_codec_inb(const struct snd_azf3328 *chip, int reg)
+snd_azf3328_codec_inb(const struct snd_azf3328 *chip, unsigned reg)
 {
-	return inb(chip->codec_port + reg);
+	return inb(chip->codec_io + reg);
 }
 
 static inline void
-snd_azf3328_codec_outw(const struct snd_azf3328 *chip, int reg, u16 value)
+snd_azf3328_codec_outw(const struct snd_azf3328 *chip, unsigned reg, u16 value)
 {
-	outw(value, chip->codec_port + reg);
+	outw(value, chip->codec_io + reg);
 }
 
 static inline u16
-snd_azf3328_codec_inw(const struct snd_azf3328 *chip, int reg)
+snd_azf3328_codec_inw(const struct snd_azf3328 *chip, unsigned reg)
+{
+	return inw(chip->codec_io + reg);
+}
+
+static inline void
+snd_azf3328_codec_outl(const struct snd_azf3328 *chip, unsigned reg, u32 value)
+{
+	outl(value, chip->codec_io + reg);
+}
+
+static inline u32
+snd_azf3328_codec_inl(const struct snd_azf3328 *chip, unsigned reg)
 {
-	return inw(chip->codec_port + reg);
+	return inl(chip->codec_io + reg);
 }
 
 static inline void
-snd_azf3328_codec_outl(const struct snd_azf3328 *chip, int reg, u32 value)
+snd_azf3328_game_outb(const struct snd_azf3328 *chip, unsigned reg, u8 value)
 {
-	outl(value, chip->codec_port + reg);
+	outb(value, chip->game_io + reg);
 }
 
 static inline void
-snd_azf3328_io2_outb(const struct snd_azf3328 *chip, int reg, u8 value)
+snd_azf3328_game_outw(const struct snd_azf3328 *chip, unsigned reg, u16 value)
 {
-	outb(value, chip->io2_port + reg);
+	outw(value, chip->game_io + reg);
 }
 
 static inline u8
-snd_azf3328_io2_inb(const struct snd_azf3328 *chip, int reg)
+snd_azf3328_game_inb(const struct snd_azf3328 *chip, unsigned reg)
+{
+	return inb(chip->game_io + reg);
+}
+
+static inline u16
+snd_azf3328_game_inw(const struct snd_azf3328 *chip, unsigned reg)
 {
-	return inb(chip->io2_port + reg);
+	return inw(chip->game_io + reg);
 }
 
 static inline void
-snd_azf3328_mixer_outw(const struct snd_azf3328 *chip, int reg, u16 value)
+snd_azf3328_mixer_outw(const struct snd_azf3328 *chip, unsigned reg, u16 value)
 {
-	outw(value, chip->mixer_port + reg);
+	outw(value, chip->mixer_io + reg);
 }
 
 static inline u16
-snd_azf3328_mixer_inw(const struct snd_azf3328 *chip, int reg)
+snd_azf3328_mixer_inw(const struct snd_azf3328 *chip, unsigned reg)
 {
-	return inw(chip->mixer_port + reg);
+	return inw(chip->mixer_io + reg);
 }
 
-static void
-snd_azf3328_mixer_set_mute(const struct snd_azf3328 *chip, int reg, int do_mute)
+#define AZF_MUTE_BIT 0x80
+
+static int
+snd_azf3328_mixer_set_mute(const struct snd_azf3328 *chip,
+			   unsigned reg, int do_mute
+)
 {
-	unsigned long portbase = chip->mixer_port + reg + 1;
-	unsigned char oldval;
+	unsigned long portbase = chip->mixer_io + reg + 1;
+	int updated;
 
 	/* the mute bit is on the *second* (i.e. right) register of a
 	 * left/right channel setting */
-	oldval = inb(portbase);
-	if (do_mute)
-		oldval |= 0x80;
-	else
-		oldval &= ~0x80;
-	outb(oldval, portbase);
+	updated = snd_azf3328_io_reg_setb(portbase, AZF_MUTE_BIT, do_mute);
+
+	/* indicate whether it was muted before */
+	return (do_mute) ? !updated : updated;
 }
 
 static void
-snd_azf3328_mixer_write_volume_gradually(const struct snd_azf3328 *chip, int reg, unsigned char dst_vol_left, unsigned char dst_vol_right, int chan_sel, int delay)
+snd_azf3328_mixer_write_volume_gradually(const struct snd_azf3328 *chip,
+					 unsigned reg,
+					 unsigned char dst_vol_left,
+					 unsigned char dst_vol_right,
+					 int chan_sel, int delay
+)
 {
-	unsigned long portbase = chip->mixer_port + reg;
+	unsigned long portbase = chip->mixer_io + reg;
 	unsigned char curr_vol_left = 0, curr_vol_right = 0;
-	int left_done = 0, right_done = 0;
-	
+	int left_change = 0, right_change = 0;
+
 	snd_azf3328_dbgcallenter();
-	if (chan_sel & SET_CHAN_LEFT)
+
+	if (chan_sel & SET_CHAN_LEFT) {
 		curr_vol_left  = inb(portbase + 1);
-	else
-		left_done = 1;
-	if (chan_sel & SET_CHAN_RIGHT)
+
+		/* take care of muting flag contained in left channel */
+		if (curr_vol_left & AZF_MUTE_BIT)
+			dst_vol_left |= AZF_MUTE_BIT;
+		else
+			dst_vol_left &= ~AZF_MUTE_BIT;
+
+		left_change = (curr_vol_left > dst_vol_left) ? -1 : 1;
+	}
+
+	if (chan_sel & SET_CHAN_RIGHT) {
 		curr_vol_right = inb(portbase + 0);
-	else
-		right_done = 1;
-	
-	/* take care of muting flag (0x80) contained in left channel */
-	if (curr_vol_left & 0x80)
-		dst_vol_left |= 0x80;
-	else
-		dst_vol_left &= ~0x80;
+
+		right_change = (curr_vol_right > dst_vol_right) ? -1 : 1;
+	}
 
 	do {
-		if (!left_done) {
-			if (curr_vol_left > dst_vol_left)
-				curr_vol_left--;
-			else
-			if (curr_vol_left < dst_vol_left)
-				curr_vol_left++;
-			else
-			    left_done = 1;
-			outb(curr_vol_left, portbase + 1);
+		if (left_change) {
+			if (curr_vol_left != dst_vol_left) {
+				curr_vol_left += left_change;
+				outb(curr_vol_left, portbase + 1);
+			} else
+			    left_change = 0;
 		}
-		if (!right_done) {
-			if (curr_vol_right > dst_vol_right)
-				curr_vol_right--;
-			else
-			if (curr_vol_right < dst_vol_right)
-				curr_vol_right++;
-			else
-			    right_done = 1;
+		if (right_change) {
+			if (curr_vol_right != dst_vol_right) {
+				curr_vol_right += right_change;
+
 			/* during volume change, the right channel is crackling
 			 * somewhat more than the left channel, unfortunately.
 			 * This seems to be a hardware issue. */
-			outb(curr_vol_right, portbase + 0);
+				outb(curr_vol_right, portbase + 0);
+			} else
+			    right_change = 0;
 		}
 		if (delay)
 			mdelay(delay);
-	} while ((!left_done) || (!right_done));
+	} while ((left_change) || (right_change));
 	snd_azf3328_dbgcallleave();
 }
 
@@ -379,7 +490,7 @@ snd_azf3328_mixer_write_volume_gradually(const struct snd_azf3328 *chip, int reg
  * general mixer element
  */
 struct azf3328_mixer_reg {
-	unsigned int reg;
+	unsigned reg;
 	unsigned int lchan_shift, rchan_shift;
 	unsigned int mask;
 	unsigned int invert: 1;
@@ -544,13 +655,14 @@ snd_azf3328_info_mixer_enum(struct snd_kcontrol *kcontrol,
 		"Mix", "Mic"
 	};
 	static const char * const texts3[] = {
-                "Mic", "CD", "Video", "Aux",
+		"Mic", "CD", "Video", "Aux",
 		"Line", "Mix", "Mix Mono", "Phone"
         };
 	static const char * const texts4[] = {
 		"pre 3D", "post 3D"
         };
 	struct azf3328_mixer_reg reg;
+	const char *p = NULL;
 
 	snd_azf3328_mixer_reg_decode(&reg, kcontrol->private_value);
         uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
@@ -561,18 +673,20 @@ snd_azf3328_info_mixer_enum(struct snd_kcontrol *kcontrol,
 	if (reg.reg == IDX_MIXER_ADVCTL2) {
 		switch(reg.lchan_shift) {
 		case 8: /* modem out sel */
-			strcpy(uinfo->value.enumerated.name, texts1[uinfo->value.enumerated.item]);
+			p = texts1[uinfo->value.enumerated.item];
 			break;
 		case 9: /* mono sel source */
-			strcpy(uinfo->value.enumerated.name, texts2[uinfo->value.enumerated.item]);
+			p = texts2[uinfo->value.enumerated.item];
 			break;
 		case 15: /* PCM Out Path */
-			strcpy(uinfo->value.enumerated.name, texts4[uinfo->value.enumerated.item]);
+			p = texts4[uinfo->value.enumerated.item];
 			break;
 		}
 	} else
-        	strcpy(uinfo->value.enumerated.name, texts3[uinfo->value.enumerated.item]
-);
+	if (reg.reg == IDX_MIXER_REC_SELECT)
+		p = texts3[uinfo->value.enumerated.item];
+
+	strcpy(uinfo->value.enumerated.name, p);
         return 0;
 }
 
@@ -583,7 +697,7 @@ snd_azf3328_get_mixer_enum(struct snd_kcontrol *kcontrol,
         struct snd_azf3328 *chip = snd_kcontrol_chip(kcontrol);
 	struct azf3328_mixer_reg reg;
         unsigned short val;
-        
+
 	snd_azf3328_mixer_reg_decode(&reg, kcontrol->private_value);
 	val = snd_azf3328_mixer_inw(chip, reg.reg);
 	if (reg.reg == IDX_MIXER_REC_SELECT) {
@@ -605,7 +719,7 @@ snd_azf3328_put_mixer_enum(struct snd_kcontrol *kcontrol,
         struct snd_azf3328 *chip = snd_kcontrol_chip(kcontrol);
 	struct azf3328_mixer_reg reg;
 	unsigned int oreg, nreg, val;
-        
+
 	snd_azf3328_mixer_reg_decode(&reg, kcontrol->private_value);
 	oreg = snd_azf3328_mixer_inw(chip, reg.reg);
 	val = oreg;
@@ -717,15 +831,16 @@ snd_azf3328_mixer_new(struct snd_azf3328 *chip)
 	snd_azf3328_mixer_outw(chip, IDX_MIXER_RESET, 0x0000);
 
 	/* mute and zero volume channels */
-	for (idx = 0; idx < ARRAY_SIZE(snd_azf3328_init_values); idx++) {
+	for (idx = 0; idx < ARRAY_SIZE(snd_azf3328_init_values); ++idx) {
 		snd_azf3328_mixer_outw(chip,
 			snd_azf3328_init_values[idx][0],
 			snd_azf3328_init_values[idx][1]);
 	}
-	
+
 	/* add mixer controls */
 	sw = snd_azf3328_mixer_controls;
-	for (idx = 0; idx < ARRAY_SIZE(snd_azf3328_mixer_controls); idx++, sw++) {
+	for (idx = 0; idx < ARRAY_SIZE(snd_azf3328_mixer_controls);
+			++idx, ++sw) {
 		if ((err = snd_ctl_add(chip->card, snd_ctl_new1(sw, chip))) < 0)
 			return err;
 	}
@@ -757,8 +872,8 @@ snd_azf3328_hw_free(struct snd_pcm_substream *substream)
 }
 
 static void
-snd_azf3328_setfmt(struct snd_azf3328 *chip,
-			       unsigned int reg,
+snd_azf3328_codec_setfmt(struct snd_azf3328 *chip,
+			       unsigned reg,
 			       unsigned int bitrate,
 			       unsigned int format_width,
 			       unsigned int channels
@@ -769,24 +884,25 @@ snd_azf3328_setfmt(struct snd_azf3328 *chip,
 
 	snd_azf3328_dbgcallenter();
 	switch (bitrate) {
-	case  4000: val |= SOUNDFORMAT_FREQ_SUSPECTED_4000; break;
-	case  4800: val |= SOUNDFORMAT_FREQ_SUSPECTED_4800; break;
-	case  5512: val |= SOUNDFORMAT_FREQ_5510; break; /* the AZF3328 names it "5510" for some strange reason */
-	case  6620: val |= SOUNDFORMAT_FREQ_6620; break;
-	case  8000: val |= SOUNDFORMAT_FREQ_8000; break;
-	case  9600: val |= SOUNDFORMAT_FREQ_9600; break;
-	case 11025: val |= SOUNDFORMAT_FREQ_11025; break;
-	case 13240: val |= SOUNDFORMAT_FREQ_SUSPECTED_13240; break;
-	case 16000: val |= SOUNDFORMAT_FREQ_16000; break;
-	case 22050: val |= SOUNDFORMAT_FREQ_22050; break;
-	case 32000: val |= SOUNDFORMAT_FREQ_32000; break;
-	case 44100: val |= SOUNDFORMAT_FREQ_44100; break;
-	case 48000: val |= SOUNDFORMAT_FREQ_48000; break;
-	case 66200: val |= SOUNDFORMAT_FREQ_SUSPECTED_66200; break;
+	case AZF_FREQ_4000:  val |= SOUNDFORMAT_FREQ_SUSPECTED_4000; break;
+	case AZF_FREQ_4800:  val |= SOUNDFORMAT_FREQ_SUSPECTED_4800; break;
+	case AZF_FREQ_5512:
+		/* the AZF3328 names it "5510" for some strange reason */
+			     val |= SOUNDFORMAT_FREQ_5510; break;
+	case AZF_FREQ_6620:  val |= SOUNDFORMAT_FREQ_6620; break;
+	case AZF_FREQ_8000:  val |= SOUNDFORMAT_FREQ_8000; break;
+	case AZF_FREQ_9600:  val |= SOUNDFORMAT_FREQ_9600; break;
+	case AZF_FREQ_11025: val |= SOUNDFORMAT_FREQ_11025; break;
+	case AZF_FREQ_13240: val |= SOUNDFORMAT_FREQ_SUSPECTED_13240; break;
+	case AZF_FREQ_16000: val |= SOUNDFORMAT_FREQ_16000; break;
+	case AZF_FREQ_22050: val |= SOUNDFORMAT_FREQ_22050; break;
+	case AZF_FREQ_32000: val |= SOUNDFORMAT_FREQ_32000; break;
 	default:
 		snd_printk(KERN_WARNING "unknown bitrate %d, assuming 44.1kHz!\n", bitrate);
-		val |= SOUNDFORMAT_FREQ_44100;
-		break;
+		/* fall-through */
+	case AZF_FREQ_44100: val |= SOUNDFORMAT_FREQ_44100; break;
+	case AZF_FREQ_48000: val |= SOUNDFORMAT_FREQ_48000; break;
+	case AZF_FREQ_66200: val |= SOUNDFORMAT_FREQ_SUSPECTED_66200; break;
 	}
 	/* val = 0xff07; 3m27.993s (65301Hz; -> 64000Hz???) hmm, 66120, 65967, 66123 */
 	/* val = 0xff09; 17m15.098s (13123,478Hz; -> 12000Hz???) hmm, 13237.2Hz? */
@@ -805,10 +921,10 @@ snd_azf3328_setfmt(struct snd_azf3328 *chip,
 		val |= SOUNDFORMAT_FLAG_16BIT;
 
 	spin_lock_irqsave(&chip->reg_lock, flags);
-	
+
 	/* set bitrate/format */
 	snd_azf3328_codec_outw(chip, reg, val);
-	
+
 	/* changing the bitrate/format settings switches off the
 	 * audio output with an annoying click in case of 8/16bit format change
 	 * (maybe shutting down DAC/ADC?), thus immediately
@@ -830,31 +946,81 @@ snd_azf3328_setfmt(struct snd_azf3328 *chip,
 	snd_azf3328_dbgcallleave();
 }
 
+static inline void
+snd_azf3328_codec_setfmt_lowpower(struct snd_azf3328 *chip,
+			    unsigned reg
+)
+{
+	/* choose lowest frequency for low power consumption.
+	 * While this will cause louder noise due to rather coarse frequency,
+	 * it should never matter since output should always
+	 * get disabled properly when idle anyway. */
+	snd_azf3328_codec_setfmt(chip, reg, AZF_FREQ_4000, 8, 1);
+}
+
+static inline void
+snd_azf3328_codec_enable(struct snd_azf3328 *chip, int enable)
+{
+	/* no idea what exactly is being done here, but I strongly assume it's
+	 * PM related */
+	snd_azf3328_io_reg_setw(
+		chip->codec_io+IDX_IO_6AH,
+		IO_6A_PAUSE_PLAYBACK_BIT8,
+		!enable
+	);
+}
+
+static void
+snd_azf3328_codec_activity(struct snd_azf3328 *chip,
+				enum snd_azf3328_stream_index stream_type,
+				int enable
+)
+{
+	int need_change = (chip->audio_stream[stream_type].running != enable);
+
+	snd_azf3328_dbgplay(
+		"codec_activity: type %d, enable %d, need_change %d\n",
+				stream_type, enable, need_change
+	);
+	if (need_change) {
+		enum snd_azf3328_stream_index other =
+			(stream_type == AZF_PLAYBACK) ?
+				AZF_CAPTURE : AZF_PLAYBACK;
+		/* small check to prevent shutting down the other party
+		 * in case it's active */
+		if ((enable) || !(chip->audio_stream[other].running))
+			snd_azf3328_codec_enable(chip, enable);
+
+		/* ...and adjust clock, too
+		 * (reduce noise and power consumption) */
+		if (!enable)
+			snd_azf3328_codec_setfmt_lowpower(
+				chip,
+				chip->audio_stream[stream_type].portbase
+					+ IDX_IO_PLAY_SOUNDFORMAT
+			);
+	}
+	chip->audio_stream[stream_type].running = enable;
+}
+
 static void
 snd_azf3328_setdmaa(struct snd_azf3328 *chip,
 				long unsigned int addr,
                                 unsigned int count,
                                 unsigned int size,
-				int do_recording)
+				enum snd_azf3328_stream_index stream_type
+)
 {
-	unsigned long flags, portbase;
-	unsigned int is_running;
-
 	snd_azf3328_dbgcallenter();
-	if (do_recording) {
-		/* access capture registers, i.e. skip playback reg section */
-		portbase = chip->codec_port + 0x20;
-		is_running = chip->is_recording;
-	} else {
-		/* access the playback register section */
-		portbase = chip->codec_port + 0x00;
-		is_running = chip->is_playing;
-	}
+	if (!chip->audio_stream[stream_type].running) {
+		/* AZF3328 uses a two buffer pointer DMA playback approach */
+
+		unsigned long flags, portbase, addr_area2;
+
+		/* width 32bit (prevent overflow): */
+		unsigned long count_areas, count_tmp;
 
-	/* AZF3328 uses a two buffer pointer DMA playback approach */
-	if (!is_running) {
-		unsigned long addr_area2;
-		unsigned long count_areas, count_tmp; /* width 32bit -- overflow!! */
+		portbase = chip->audio_stream[stream_type].portbase;
 		count_areas = size/2;
 		addr_area2 = addr+count_areas;
 		count_areas--; /* max. index */
@@ -884,11 +1050,11 @@ snd_azf3328_playback_prepare(struct snd_pcm_substream *substream)
 
 	snd_azf3328_dbgcallenter();
 #if 0
-	snd_azf3328_setfmt(chip, IDX_IO_PLAY_SOUNDFORMAT,
+	snd_azf3328_codec_setfmt(chip, IDX_IO_PLAY_SOUNDFORMAT,
 		runtime->rate,
 		snd_pcm_format_width(runtime->format),
 		runtime->channels);
-	snd_azf3328_setdmaa(chip, runtime->dma_addr, count, size, 0);
+	snd_azf3328_setdmaa(chip, runtime->dma_addr, count, size, AZF_PLAYBACK);
 #endif
 	snd_azf3328_dbgcallleave();
 	return 0;
@@ -906,11 +1072,11 @@ snd_azf3328_capture_prepare(struct snd_pcm_substream *substream)
 
 	snd_azf3328_dbgcallenter();
 #if 0
-	snd_azf3328_setfmt(chip, IDX_IO_REC_SOUNDFORMAT,
+	snd_azf3328_codec_setfmt(chip, IDX_IO_REC_SOUNDFORMAT,
 		runtime->rate,
 		snd_pcm_format_width(runtime->format),
 		runtime->channels);
-	snd_azf3328_setdmaa(chip, runtime->dma_addr, count, size, 1);
+	snd_azf3328_setdmaa(chip, runtime->dma_addr, count, size, AZF_CAPTURE);
 #endif
 	snd_azf3328_dbgcallleave();
 	return 0;
@@ -923,6 +1089,7 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	int result = 0;
 	unsigned int status1;
+	int previously_muted;
 
 	snd_azf3328_dbgcalls("snd_azf3328_playback_trigger cmd %d\n", cmd);
 
@@ -930,20 +1097,23 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 	case SNDRV_PCM_TRIGGER_START:
 		snd_azf3328_dbgplay("START PLAYBACK\n");
 
-		/* mute WaveOut */
-		snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 1);
+		/* mute WaveOut (avoid clicking during setup) */
+		previously_muted =
+			snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 1);
 
-		snd_azf3328_setfmt(chip, IDX_IO_PLAY_SOUNDFORMAT,
+		snd_azf3328_codec_setfmt(chip, IDX_IO_PLAY_SOUNDFORMAT,
 			runtime->rate,
 			snd_pcm_format_width(runtime->format),
 			runtime->channels);
 
 		spin_lock(&chip->reg_lock);
-		/* stop playback */
+		/* first, remember current value: */
 		status1 = snd_azf3328_codec_inw(chip, IDX_IO_PLAY_FLAGS);
+
+		/* stop playback */
 		status1 &= ~DMA_RESUME;
 		snd_azf3328_codec_outw(chip, IDX_IO_PLAY_FLAGS, status1);
-	    
+
 		/* FIXME: clear interrupts or what??? */
 		snd_azf3328_codec_outw(chip, IDX_IO_PLAY_IRQTYPE, 0xffff);
 		spin_unlock(&chip->reg_lock);
@@ -951,7 +1121,7 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 		snd_azf3328_setdmaa(chip, runtime->dma_addr,
 			snd_pcm_lib_period_bytes(substream),
 			snd_pcm_lib_buffer_bytes(substream),
-			0);
+			AZF_PLAYBACK);
 
 		spin_lock(&chip->reg_lock);
 #ifdef WIN9X
@@ -978,30 +1148,35 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 			DMA_SOMETHING_ELSE);
 #endif
 		spin_unlock(&chip->reg_lock);
+		snd_azf3328_codec_activity(chip, AZF_PLAYBACK, 1);
 
 		/* now unmute WaveOut */
-		snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 0);
+		if (!previously_muted)
+			snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 0);
 
-		chip->is_playing = 1;
 		snd_azf3328_dbgplay("STARTED PLAYBACK\n");
 		break;
 	case SNDRV_PCM_TRIGGER_RESUME:
 		snd_azf3328_dbgplay("RESUME PLAYBACK\n");
 		/* resume playback if we were active */
-		if (chip->is_playing)
+		spin_lock(&chip->reg_lock);
+		if (chip->audio_stream[AZF_PLAYBACK].running)
 			snd_azf3328_codec_outw(chip, IDX_IO_PLAY_FLAGS,
 				snd_azf3328_codec_inw(chip, IDX_IO_PLAY_FLAGS) | DMA_RESUME);
+		spin_unlock(&chip->reg_lock);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 		snd_azf3328_dbgplay("STOP PLAYBACK\n");
 
-		/* mute WaveOut */
-		snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 1);
+		/* mute WaveOut (avoid clicking during setup) */
+		previously_muted =
+			snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 1);
 
 		spin_lock(&chip->reg_lock);
-		/* stop playback */
+		/* first, remember current value: */
 		status1 = snd_azf3328_codec_inw(chip, IDX_IO_PLAY_FLAGS);
 
+		/* stop playback */
 		status1 &= ~DMA_RESUME;
 		snd_azf3328_codec_outw(chip, IDX_IO_PLAY_FLAGS, status1);
 
@@ -1013,10 +1188,12 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 		status1 &= ~DMA_PLAY_SOMETHING1;
 		snd_azf3328_codec_outw(chip, IDX_IO_PLAY_FLAGS, status1);
 		spin_unlock(&chip->reg_lock);
-	    
+		snd_azf3328_codec_activity(chip, AZF_PLAYBACK, 0);
+
 		/* now unmute WaveOut */
-		snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 0);
-		chip->is_playing = 0;
+		if (!previously_muted)
+			snd_azf3328_mixer_set_mute(chip, IDX_MIXER_WAVEOUT, 0);
+
 		snd_azf3328_dbgplay("STOPPED PLAYBACK\n");
 		break;
 	case SNDRV_PCM_TRIGGER_SUSPEND:
@@ -1035,7 +1212,7 @@ snd_azf3328_playback_trigger(struct snd_pcm_substream *substream, int cmd)
 		printk(KERN_ERR "FIXME: unknown trigger mode!\n");
                 return -EINVAL;
 	}
-	
+
 	snd_azf3328_dbgcallleave();
 	return result;
 }
@@ -1057,17 +1234,19 @@ snd_azf3328_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 
 		snd_azf3328_dbgplay("START CAPTURE\n");
 
-		snd_azf3328_setfmt(chip, IDX_IO_REC_SOUNDFORMAT,
+		snd_azf3328_codec_setfmt(chip, IDX_IO_REC_SOUNDFORMAT,
 			runtime->rate,
 			snd_pcm_format_width(runtime->format),
 			runtime->channels);
 
 		spin_lock(&chip->reg_lock);
-		/* stop recording */
+		/* first, remember current value: */
 		status1 = snd_azf3328_codec_inw(chip, IDX_IO_REC_FLAGS);
+
+		/* stop recording */
 		status1 &= ~DMA_RESUME;
 		snd_azf3328_codec_outw(chip, IDX_IO_REC_FLAGS, status1);
-	    
+
 		/* FIXME: clear interrupts or what??? */
 		snd_azf3328_codec_outw(chip, IDX_IO_REC_IRQTYPE, 0xffff);
 		spin_unlock(&chip->reg_lock);
@@ -1075,7 +1254,7 @@ snd_azf3328_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 		snd_azf3328_setdmaa(chip, runtime->dma_addr,
 			snd_pcm_lib_period_bytes(substream),
 			snd_pcm_lib_buffer_bytes(substream),
-			1);
+			AZF_CAPTURE);
 
 		spin_lock(&chip->reg_lock);
 #ifdef WIN9X
@@ -1102,24 +1281,27 @@ snd_azf3328_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 			DMA_SOMETHING_ELSE);
 #endif
 		spin_unlock(&chip->reg_lock);
+		snd_azf3328_codec_activity(chip, AZF_CAPTURE, 1);
 
-		chip->is_recording = 1;
 		snd_azf3328_dbgplay("STARTED CAPTURE\n");
 		break;
 	case SNDRV_PCM_TRIGGER_RESUME:
 		snd_azf3328_dbgplay("RESUME CAPTURE\n");
 		/* resume recording if we were active */
-		if (chip->is_recording)
+		spin_lock(&chip->reg_lock);
+		if (chip->audio_stream[AZF_CAPTURE].running)
 			snd_azf3328_codec_outw(chip, IDX_IO_REC_FLAGS,
 				snd_azf3328_codec_inw(chip, IDX_IO_REC_FLAGS) | DMA_RESUME);
+		spin_unlock(&chip->reg_lock);
 		break;
         case SNDRV_PCM_TRIGGER_STOP:
 		snd_azf3328_dbgplay("STOP CAPTURE\n");
 
 		spin_lock(&chip->reg_lock);
-		/* stop recording */
+		/* first, remember current value: */
 		status1 = snd_azf3328_codec_inw(chip, IDX_IO_REC_FLAGS);
 
+		/* stop recording */
 		status1 &= ~DMA_RESUME;
 		snd_azf3328_codec_outw(chip, IDX_IO_REC_FLAGS, status1);
 
@@ -1129,8 +1311,8 @@ snd_azf3328_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 		status1 &= ~DMA_PLAY_SOMETHING1;
 		snd_azf3328_codec_outw(chip, IDX_IO_REC_FLAGS, status1);
 		spin_unlock(&chip->reg_lock);
-	    
-		chip->is_recording = 0;
+		snd_azf3328_codec_activity(chip, AZF_CAPTURE, 0);
+
 		snd_azf3328_dbgplay("STOPPED CAPTURE\n");
 		break;
 	case SNDRV_PCM_TRIGGER_SUSPEND:
@@ -1149,7 +1331,7 @@ snd_azf3328_capture_trigger(struct snd_pcm_substream *substream, int cmd)
 		printk(KERN_ERR "FIXME: unknown trigger mode!\n");
                 return -EINVAL;
 	}
-	
+
 	snd_azf3328_dbgcallleave();
 	return result;
 }
@@ -1162,11 +1344,11 @@ snd_azf3328_playback_pointer(struct snd_pcm_substream *substream)
 	snd_pcm_uframes_t frmres;
 
 #ifdef QUERY_HARDWARE
-	bufptr = inl(chip->codec_port+IDX_IO_PLAY_DMA_START_1);
+	bufptr = snd_azf3328_codec_inl(chip, IDX_IO_PLAY_DMA_START_1);