--- /dev/null
+From 76c252645ad542bd35ce52230635f36e3c0f730d Mon Sep 17 00:00:00 2001
+From: Gordon Garrity <gordon@iqaudio.com>
+Date: Sat, 8 Mar 2014 16:56:57 +0000
+Subject: [PATCH] Add IQaudIO Sound Card support for Raspberry Pi
+
+Set a limit of 0dB on Digital Volume Control
+
+The main volume control in the PCM512x DAC has a range up to
++24dB. This is dangerously loud and can potentially cause massive
+clipping in the output stages. Therefore this sets a sensible
+limit of 0dB for this control.
+
+Allow up to 24dB digital gain to be applied when using IQAudIO DAC+
+
+24db_digital_gain DT param can be used to specify that PCM512x
+codec "Digital" volume control should not be limited to 0dB gain,
+and if specified will allow the full 24dB gain.
+
+Modify IQAudIO DAC+ ASoC driver to set card/dai config from dt
+
+Add the ability to set the card name, dai name and dai stream name, from
+dt config.
+
+Signed-off-by: DigitalDreamtime <clive.messer@digitaldreamtime.co.uk>
+
+IQaudIO: auto-mute for AMP+ and DigiAMP+
+
+IQAudIO amplifier mute via GPIO22. Add dt params for "one-shot" unmute
+and auto mute.
+
+Revision 2, auto mute implementing HiassofT suggestion to mute/unmute
+using set_bias_level, rather than startup/shutdown....
+"By default DAPM waits 5 seconds (pmdown_time) before shutting down
+playback streams so a close/stop immediately followed by open/start
+doesn't trigger an amp mute+unmute."
+
+Tested on both AMP+ (via DAC+) and DigiAMP+, with both options...
+
+dtoverlay=iqaudio-dacplus,unmute_amp
+ "one-shot" unmute when kernel module loads.
+
+dtoverlay=iqaudio-dacplus,auto_mute_amp
+ Unmute amp when ALSA device opened by a client. Mute, with 5 second delay
+ when ALSA device closed. (Re-opening the device within the 5 second close
+ window, will cancel mute.)
+
+Revision 4, using gpiod.
+
+Revision 5, clean-up formatting before adding mute code.
+ - Convert tab plus 4 space formatting to 2x tab
+ - Remove '// NOT USED' commented code
+
+Revision 6, don't attempt to "one-shot" unmute amp, unless card is
+successfully registered.
+
+Signed-off-by: DigitalDreamtime <clive.messer@digitaldreamtime.co.uk>
+
+ASoC: iqaudio-dac: fix S24_LE format
+
+Remove set_bclk_ratio call so 24-bit data is transmitted in
+24 bclk cycles.
+
+Signed-off-by: Matthias Reichl <hias@horus.com>
+---
+ sound/soc/bcm/iqaudio-dac.c | 221 ++++++++++++++++++++++++++++++++++++
+ 1 file changed, 221 insertions(+)
+ create mode 100644 sound/soc/bcm/iqaudio-dac.c
+
+--- /dev/null
++++ b/sound/soc/bcm/iqaudio-dac.c
+@@ -0,0 +1,221 @@
++/*
++ * ASoC Driver for IQaudIO DAC
++ *
++ * Author: Florian Meier <florian.meier@koalo.de>
++ * Copyright 2013
++ *
++ * This program is free software; you can redistribute it and/or
++ * modify it under the terms of the GNU General Public License
++ * version 2 as published by the Free Software Foundation.
++ *
++ * This program is distributed in the hope that it will be useful, but
++ * WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
++ * General Public License for more details.
++ */
++
++#include <linux/module.h>
++#include <linux/gpio/consumer.h>
++#include <linux/platform_device.h>
++
++#include <sound/core.h>
++#include <sound/pcm.h>
++#include <sound/pcm_params.h>
++#include <sound/soc.h>
++#include <sound/jack.h>
++
++static bool digital_gain_0db_limit = true;
++
++static struct gpio_desc *mute_gpio;
++
++static int snd_rpi_iqaudio_dac_init(struct snd_soc_pcm_runtime *rtd)
++{
++ if (digital_gain_0db_limit)
++ {
++ int ret;
++ struct snd_soc_card *card = rtd->card;
++
++ ret = snd_soc_limit_volume(card, "Digital Playback Volume", 207);
++ if (ret < 0)
++ dev_warn(card->dev, "Failed to set volume limit: %d\n", ret);
++ }
++
++ return 0;
++}
++
++static void snd_rpi_iqaudio_gpio_mute(struct snd_soc_card *card)
++{
++ if (mute_gpio) {
++ dev_info(card->dev, "%s: muting amp using GPIO22\n",
++ __func__);
++ gpiod_set_value_cansleep(mute_gpio, 0);
++ }
++}
++
++static void snd_rpi_iqaudio_gpio_unmute(struct snd_soc_card *card)
++{
++ if (mute_gpio) {
++ dev_info(card->dev, "%s: un-muting amp using GPIO22\n",
++ __func__);
++ gpiod_set_value_cansleep(mute_gpio, 1);
++ }
++}
++
++static int snd_rpi_iqaudio_set_bias_level(struct snd_soc_card *card,
++ struct snd_soc_dapm_context *dapm, enum snd_soc_bias_level level)
++{
++ struct snd_soc_pcm_runtime *rtd;
++ struct snd_soc_dai *codec_dai;
++
++ rtd = snd_soc_get_pcm_runtime(card, card->dai_link[0].name);
++ codec_dai = rtd->codec_dai;
++
++ if (dapm->dev != codec_dai->dev)
++ return 0;
++
++ switch (level) {
++ case SND_SOC_BIAS_PREPARE:
++ if (dapm->bias_level != SND_SOC_BIAS_STANDBY)
++ break;
++
++ /* UNMUTE AMP */
++ snd_rpi_iqaudio_gpio_unmute(card);
++
++ break;
++ case SND_SOC_BIAS_STANDBY:
++ if (dapm->bias_level != SND_SOC_BIAS_PREPARE)
++ break;
++
++ /* MUTE AMP */
++ snd_rpi_iqaudio_gpio_mute(card);
++
++ break;
++ default:
++ break;
++ }
++
++ return 0;
++}
++
++static struct snd_soc_dai_link snd_rpi_iqaudio_dac_dai[] = {
++{
++ .cpu_dai_name = "bcm2708-i2s.0",
++ .codec_dai_name = "pcm512x-hifi",
++ .platform_name = "bcm2708-i2s.0",
++ .codec_name = "pcm512x.1-004c",
++ .dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
++ SND_SOC_DAIFMT_CBS_CFS,
++ .init = snd_rpi_iqaudio_dac_init,
++},
++};
++
++/* audio machine driver */
++static struct snd_soc_card snd_rpi_iqaudio_dac = {
++ .owner = THIS_MODULE,
++ .dai_link = snd_rpi_iqaudio_dac_dai,
++ .num_links = ARRAY_SIZE(snd_rpi_iqaudio_dac_dai),
++};
++
++static int snd_rpi_iqaudio_dac_probe(struct platform_device *pdev)
++{
++ int ret = 0;
++ bool gpio_unmute = false;
++
++ snd_rpi_iqaudio_dac.dev = &pdev->dev;
++
++ if (pdev->dev.of_node) {
++ struct device_node *i2s_node;
++ struct snd_soc_card *card = &snd_rpi_iqaudio_dac;
++ struct snd_soc_dai_link *dai = &snd_rpi_iqaudio_dac_dai[0];
++ bool auto_gpio_mute = false;
++
++ i2s_node = of_parse_phandle(pdev->dev.of_node,
++ "i2s-controller", 0);
++ if (i2s_node) {
++ dai->cpu_dai_name = NULL;
++ dai->cpu_of_node = i2s_node;
++ dai->platform_name = NULL;
++ dai->platform_of_node = i2s_node;
++ }
++
++ digital_gain_0db_limit = !of_property_read_bool(
++ pdev->dev.of_node, "iqaudio,24db_digital_gain");
++
++ if (of_property_read_string(pdev->dev.of_node, "card_name",
++ &card->name))
++ card->name = "IQaudIODAC";
++
++ if (of_property_read_string(pdev->dev.of_node, "dai_name",
++ &dai->name))
++ dai->name = "IQaudIO DAC";
++
++ if (of_property_read_string(pdev->dev.of_node,
++ "dai_stream_name", &dai->stream_name))
++ dai->stream_name = "IQaudIO DAC HiFi";
++
++ /* gpio_unmute - one time unmute amp using GPIO */
++ gpio_unmute = of_property_read_bool(pdev->dev.of_node,
++ "iqaudio-dac,unmute-amp");
++
++ /* auto_gpio_mute - mute/unmute amp using GPIO */
++ auto_gpio_mute = of_property_read_bool(pdev->dev.of_node,
++ "iqaudio-dac,auto-mute-amp");
++
++ if (auto_gpio_mute || gpio_unmute) {
++ mute_gpio = devm_gpiod_get_optional(&pdev->dev, "mute",
++ GPIOD_OUT_LOW);
++ if (IS_ERR(mute_gpio)) {
++ ret = PTR_ERR(mute_gpio);
++ dev_err(&pdev->dev,
++ "Failed to get mute gpio: %d\n", ret);
++ return ret;
++ }
++
++ if (auto_gpio_mute && mute_gpio)
++ snd_rpi_iqaudio_dac.set_bias_level =
++ snd_rpi_iqaudio_set_bias_level;
++ }
++ }
++
++ ret = snd_soc_register_card(&snd_rpi_iqaudio_dac);
++ if (ret) {
++ if (ret != -EPROBE_DEFER)
++ dev_err(&pdev->dev,
++ "snd_soc_register_card() failed: %d\n", ret);
++ return ret;
++ }
++
++ if (gpio_unmute && mute_gpio)
++ snd_rpi_iqaudio_gpio_unmute(&snd_rpi_iqaudio_dac);
++
++ return 0;
++}
++
++static int snd_rpi_iqaudio_dac_remove(struct platform_device *pdev)
++{
++ snd_rpi_iqaudio_gpio_mute(&snd_rpi_iqaudio_dac);
++
++ return snd_soc_unregister_card(&snd_rpi_iqaudio_dac);
++}
++
++static const struct of_device_id iqaudio_of_match[] = {
++ { .compatible = "iqaudio,iqaudio-dac", },
++ {},
++};
++MODULE_DEVICE_TABLE(of, iqaudio_of_match);
++
++static struct platform_driver snd_rpi_iqaudio_dac_driver = {
++ .driver = {
++ .name = "snd-rpi-iqaudio-dac",
++ .owner = THIS_MODULE,
++ .of_match_table = iqaudio_of_match,
++ },
++ .probe = snd_rpi_iqaudio_dac_probe,
++ .remove = snd_rpi_iqaudio_dac_remove,
++};
++
++module_platform_driver(snd_rpi_iqaudio_dac_driver);
++
++MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>");
++MODULE_DESCRIPTION("ASoC Driver for IQAudio DAC");
++MODULE_LICENSE("GPL v2");
projects / openwrt / staging / chunkeey.git / blobdiff