ALSA: hda - Fix digital beep tone calculation

The digital beep tone is calculated in two different ways depending
on the codec chip.  The standard one is using a divider, and another
one is a linear tone for IDT/STAC codecs.  Currently, only the
latter type is used for all codecs, which resulted in a wrong tone
pitch.

This patch adds the calculation of the standard HD-audio type.
Also clean-up the fields in hda_beep struct.

Reference: bko#13162
	http://bugzilla.kernel.org/show_bug.cgi?id=13162Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_beep.c

@@ -45,16 +45,15 @@ static void snd_hda_generate_beep(struct work_struct *work)
 			AC_VERB_SET_BEEP_CONTROL, beep->tone);
 }
 
-static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
-				unsigned int code, int hz)
+/* (non-standard) Linear beep tone calculation for IDT/STAC codecs 
+ *
+ * The tone frequency of beep generator on IDT/STAC codecs is
+ * defined from the 8bit tone parameter, in Hz,
+ *    freq = 48000 * (257 - tone) / 1024
+ * that is from 12kHz to 93.75kHz in step of 46.875 hz
+ */
+static int beep_linear_tone(struct hda_beep *beep, int hz)
 {
-	struct hda_beep *beep = input_get_drvdata(dev);
-
-	switch (code) {
-	case SND_BELL:
-		if (hz)
-			hz = 1000;
-	case SND_TONE:
 	hz *= 1000; /* fixed point */
 	hz = hz - DIGBEEP_HZ_MIN;
 	if (hz < 0)
@@ -65,11 +64,45 @@ static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
 		hz /= DIGBEEP_HZ_STEP;
 		hz++;
 	}
+	return hz;
+}
+
+/* HD-audio standard beep tone parameter calculation
+ *
+ * The tone frequency in Hz is calculated as
+ *   freq = 48000 / (tone * 4)
+ * from 47Hz to 12kHz
+ */
+static int beep_standard_tone(struct hda_beep *beep, int hz)
+{
+	if (hz <= 0)
+		return 0; /* disabled */
+	hz = 12000 / hz;
+	if (hz > 0xff)
+		return 0xff;
+	if (hz <= 0)
+		return 1;
+	return hz;
+}
+
+static int snd_hda_beep_event(struct input_dev *dev, unsigned int type,
+				unsigned int code, int hz)
+{
+	struct hda_beep *beep = input_get_drvdata(dev);
+
+	switch (code) {
+	case SND_BELL:
+		if (hz)
+			hz = 1000;
+	case SND_TONE:
+		if (beep->linear_tone)
+			beep->tone = beep_linear_tone(beep, hz);
+		else
+			beep->tone = beep_standard_tone(beep, hz);
 		break;
 	default:
 		return -1;
 	}
-	beep->tone = hz;
 
 	/* schedule beep event */
 	schedule_work(&beep->beep_work);

sound/pci/hda/hda_beep.h

@@ -30,8 +30,9 @@ struct hda_beep {
 	struct hda_codec *codec;
 	char phys[32];
 	int tone;
-	int nid;
-	int enabled;
+	hda_nid_t nid;
+	unsigned int enabled:1;
+	unsigned int linear_tone:1;	/* linear tone for IDT/STAC codec */
 	struct work_struct beep_work; /* scheduled task for beep event */
 };
 

sound/pci/hda/patch_sigmatel.c

@@ -3737,6 +3737,8 @@ static int stac92xx_parse_auto_config(struct hda_codec *codec, hda_nid_t dig_out
 		err = snd_hda_attach_beep_device(codec, nid);
 		if (err < 0)
 			return err;
+		/* IDT/STAC codecs have linear beep tone parameter */
+		codec->beep->linear_tone = 1;
 		/* if no beep switch is available, make its own one */
 		caps = query_amp_caps(codec, nid, HDA_OUTPUT);
 		if (codec->beep &&