From 8a4af475fccaff7b70b3d93ef1730001a2376063 Mon Sep 17 00:00:00 2001 From: Gordon Garrity 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. --- sound/soc/bcm/Kconfig | 7 +++ sound/soc/bcm/Makefile | 2 + sound/soc/bcm/iqaudio-dac.c | 132 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 141 insertions(+) create mode 100644 sound/soc/bcm/iqaudio-dac.c --- a/sound/soc/bcm/Kconfig +++ b/sound/soc/bcm/Kconfig @@ -28,3 +28,10 @@ config SND_BCM2708_SOC_RPI_DAC select SND_SOC_PCM1794A help Say Y or M if you want to add support for RPi-DAC. + +config SND_BCM2708_SOC_IQAUDIO_DAC + tristate "Support for IQaudIO-DAC" + depends on SND_BCM2708_SOC_I2S || SND_BCM2835_SOC_I2S + select SND_SOC_PCM512x_I2C + help + Say Y or M if you want to add support for IQaudIO-DAC. --- a/sound/soc/bcm/Makefile +++ b/sound/soc/bcm/Makefile @@ -7,7 +7,9 @@ obj-$(CONFIG_SND_BCM2835_SOC_I2S) += snd snd-soc-hifiberry-dac-objs := hifiberry_dac.o snd-soc-hifiberry-digi-objs := hifiberry_digi.o snd-soc-rpi-dac-objs := rpi-dac.o +snd-soc-iqaudio-dac-objs := iqaudio-dac.o obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DAC) += snd-soc-hifiberry-dac.o obj-$(CONFIG_SND_BCM2708_SOC_HIFIBERRY_DIGI) += snd-soc-hifiberry-digi.o obj-$(CONFIG_SND_BCM2708_SOC_RPI_DAC) += snd-soc-rpi-dac.o +obj-$(CONFIG_SND_BCM2708_SOC_IQAUDIO_DAC) += snd-soc-iqaudio-dac.o --- /dev/null +++ b/sound/soc/bcm/iqaudio-dac.c @@ -0,0 +1,132 @@ +/* + * ASoC Driver for IQaudIO DAC + * + * Author: Florian Meier + * 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 +#include + +#include +#include +#include +#include +#include + +static int snd_rpi_iqaudio_dac_init(struct snd_soc_pcm_runtime *rtd) +{ + 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 int snd_rpi_iqaudio_dac_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params) +{ + struct snd_soc_pcm_runtime *rtd = substream->private_data; +// NOT USED struct snd_soc_dai *codec_dai = rtd->codec_dai; +// NOT USED struct snd_soc_codec *codec = rtd->codec; + struct snd_soc_dai *cpu_dai = rtd->cpu_dai; + + unsigned int sample_bits = + snd_pcm_format_physical_width(params_format(params)); + + return snd_soc_dai_set_bclk_ratio(cpu_dai, sample_bits * 2); +} + +/* machine stream operations */ +static struct snd_soc_ops snd_rpi_iqaudio_dac_ops = { + .hw_params = snd_rpi_iqaudio_dac_hw_params, +}; + +static struct snd_soc_dai_link snd_rpi_iqaudio_dac_dai[] = { +{ + .name = "IQaudIO DAC", + .stream_name = "IQaudIO DAC HiFi", + .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, + .ops = &snd_rpi_iqaudio_dac_ops, + .init = snd_rpi_iqaudio_dac_init, +}, +}; + +/* audio machine driver */ +static struct snd_soc_card snd_rpi_iqaudio_dac = { + .name = "IQaudIODAC", + .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; + + snd_rpi_iqaudio_dac.dev = &pdev->dev; + + if (pdev->dev.of_node) { + struct device_node *i2s_node; + struct snd_soc_dai_link *dai = &snd_rpi_iqaudio_dac_dai[0]; + 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; + } + } + + ret = snd_soc_register_card(&snd_rpi_iqaudio_dac); + if (ret) + dev_err(&pdev->dev, + "snd_soc_register_card() failed: %d\n", ret); + + return ret; +} + +static int snd_rpi_iqaudio_dac_remove(struct platform_device *pdev) +{ + 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 "); +MODULE_DESCRIPTION("ASoC Driver for IQAudio DAC"); +MODULE_LICENSE("GPL v2");