From 69fff9bbbc4d214ed22c8f89681af3871a128e35 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Fri, 10 Dec 2010 19:17:08 +0000 Subject: [PATCH] ASoC: Automatically manage WM8903 deemphasis rate Provide the user with a boolean control then automatically select the deemphasis filter most closely matching the sample rate. Signed-off-by: Mark Brown Acked-by: Liam Girdwood --- sound/soc/codecs/wm8903.c | 82 ++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 74 insertions(+), 8 deletions(-) diff --git a/sound/soc/codecs/wm8903.c b/sound/soc/codecs/wm8903.c index f9ae403..d015745 100644 --- a/sound/soc/codecs/wm8903.c +++ b/sound/soc/codecs/wm8903.c @@ -218,6 +218,9 @@ struct wm8903_priv { int sysclk; int irq; + int fs; + int deemph; + /* Reference count */ int class_w_users; @@ -457,6 +460,72 @@ static int wm8903_class_w_put(struct snd_kcontrol *kcontrol, .private_value = SOC_SINGLE_VALUE(reg, shift, max, invert) } +static int wm8903_deemph[] = { 0, 32000, 44100, 48000 }; + +static int wm8903_set_deemph(struct snd_soc_codec *codec) +{ + struct wm8903_priv *wm8903 = snd_soc_codec_get_drvdata(codec); + int val, i, best; + + /* If we're using deemphasis select the nearest available sample + * rate. + */ + if (wm8903->deemph) { + best = 1; + for (i = 2; i < ARRAY_SIZE(wm8903_deemph); i++) { + if (abs(wm8903_deemph[i] - wm8903->fs) < + abs(wm8903_deemph[best] - wm8903->fs)) + best = i; + } + + val = best << WM8903_DEEMPH_SHIFT; + } else { + best = 0; + val = 0; + } + + dev_dbg(codec->dev, "Set deemphasis %d (%dHz)\n", + best, wm8903_deemph[best]); + + return snd_soc_update_bits(codec, WM8903_DAC_DIGITAL_1, + WM8903_DEEMPH_MASK, val); +} + +static int wm8903_get_deemph(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol); + struct wm8903_priv *wm8903 = snd_soc_codec_get_drvdata(codec); + + ucontrol->value.enumerated.item[0] = wm8903->deemph; + + return 0; +} + +static int wm8903_put_deemph(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) +{ + struct snd_soc_codec *codec = snd_kcontrol_chip(kcontrol); + struct wm8903_priv *wm8903 = snd_soc_codec_get_drvdata(codec); + int deemph = ucontrol->value.enumerated.item[0]; + int ret = 0; + + if (deemph > 1) + return -EINVAL; + + mutex_lock(&codec->mutex); + if (wm8903->deemph != deemph) { + wm8903->deemph = deemph; + + wm8903_set_deemph(codec); + + ret = 1; + } + mutex_unlock(&codec->mutex); + + return ret; +} + /* ALSA can only do steps of .01dB */ static const DECLARE_TLV_DB_SCALE(digital_tlv, -7200, 75, 1); @@ -548,13 +617,6 @@ static const char *mute_mode_text[] = { static const struct soc_enum mute_mode = SOC_ENUM_SINGLE(WM8903_DAC_DIGITAL_1, 9, 2, mute_mode_text); -static const char *dac_deemphasis_text[] = { - "Disabled", "32kHz", "44.1kHz", "48kHz" -}; - -static const struct soc_enum dac_deemphasis = - SOC_ENUM_SINGLE(WM8903_DAC_DIGITAL_1, 1, 4, dac_deemphasis_text); - static const char *companding_text[] = { "ulaw", "alaw" }; @@ -662,9 +724,10 @@ SOC_DOUBLE_R_TLV("Digital Playback Volume", WM8903_DAC_DIGITAL_VOLUME_LEFT, SOC_ENUM("DAC Soft Mute Rate", soft_mute), SOC_ENUM("DAC Mute Mode", mute_mode), SOC_SINGLE("DAC Mono Switch", WM8903_DAC_DIGITAL_1, 12, 1, 0), -SOC_ENUM("DAC De-emphasis", dac_deemphasis), SOC_ENUM("DAC Companding Mode", dac_companding), SOC_SINGLE("DAC Companding Switch", WM8903_AUDIO_INTERFACE_0, 1, 1, 0), +SOC_SINGLE_BOOL_EXT("Playback Deemphasis Switch", 0, + wm8903_get_deemph, wm8903_put_deemph), /* Headphones */ SOC_DOUBLE_R("Headphone Switch", @@ -1374,6 +1437,9 @@ static int wm8903_hw_params(struct snd_pcm_substream *substream, aif2 |= bclk_divs[bclk_div].div; aif3 |= bclk / fs; + wm8903->fs = params_rate(params); + wm8903_set_deemph(codec); + snd_soc_write(codec, WM8903_CLOCK_RATES_0, clock0); snd_soc_write(codec, WM8903_CLOCK_RATES_1, clock1); snd_soc_write(codec, WM8903_AUDIO_INTERFACE_1, aif1); -- 2.7.4