ASoC: Add support for the Analog Devices AXI-I2S core

This patch adds support for the AXI-I2S softcore. The core implements a simple
bidirectional I2S transceiver and is used by Analog Devices in some of their
reference designs for various FPGA platforms.

The driver uses the generic PCM dmaengine driver for its PCM. The only
restriction is that we need to set the SND_DMAENGINE_PCM_FLAG_NO_RESIDUE flag as
the dmaengine driver for the DMA core (PL330) that is used with this core has no
residue reporting capabilities yet. This will be fixed in the future though.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Lars-Peter Clausen 2013-12-06 11:02:50 +01:00 committed by Mark Brown
parent 00e6cb2aed
commit 8f2fe34682
5 changed files with 295 additions and 0 deletions

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@ -31,6 +31,7 @@ config SND_SOC_GENERIC_DMAENGINE_PCM
select SND_DMAENGINE_PCM
# All the supported SoCs
source "sound/soc/adi/Kconfig"
source "sound/soc/atmel/Kconfig"
source "sound/soc/au1x/Kconfig"
source "sound/soc/blackfin/Kconfig"

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@ -8,6 +8,7 @@ endif
obj-$(CONFIG_SND_SOC) += snd-soc-core.o
obj-$(CONFIG_SND_SOC) += codecs/
obj-$(CONFIG_SND_SOC) += generic/
obj-$(CONFIG_SND_SOC) += adi/
obj-$(CONFIG_SND_SOC) += atmel/
obj-$(CONFIG_SND_SOC) += au1x/
obj-$(CONFIG_SND_SOC) += blackfin/

13
sound/soc/adi/Kconfig Normal file
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@ -0,0 +1,13 @@
config SND_SOC_ADI
tristate "Audio support for Analog Devices reference designs"
depends on MICROBLAZE || ARCH_ZYNQ || COMPILE_TEST
help
Audio support for various reference designs by Analog Devices.
config SND_SOC_ADI_AXI_I2S
tristate "AXI-I2S support"
depends on SND_SOC_ADI
select SND_SOC_GENERIC_DMAENGINE_PCM
select REGMAP_MMIO
help
ASoC driver for the Analog Devices AXI-I2S softcore peripheral.

3
sound/soc/adi/Makefile Normal file
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@ -0,0 +1,3 @@
snd-soc-adi-axi-i2s-objs := axi-i2s.o
obj-$(CONFIG_SND_SOC_ADI_AXI_I2S) += snd-soc-adi-axi-i2s.o

277
sound/soc/adi/axi-i2s.c Normal file
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@ -0,0 +1,277 @@
/*
* Copyright (C) 2012-2013, Analog Devices Inc.
* Author: Lars-Peter Clausen <lars@metafoo.de>
*
* Licensed under the GPL-2.
*/
#include <linux/clk.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/dmaengine_pcm.h>
#define AXI_I2S_REG_RESET 0x00
#define AXI_I2S_REG_CTRL 0x04
#define AXI_I2S_REG_CLK_CTRL 0x08
#define AXI_I2S_REG_STATUS 0x10
#define AXI_I2S_REG_RX_FIFO 0x28
#define AXI_I2S_REG_TX_FIFO 0x2C
#define AXI_I2S_RESET_GLOBAL BIT(0)
#define AXI_I2S_RESET_TX_FIFO BIT(1)
#define AXI_I2S_RESET_RX_FIFO BIT(2)
#define AXI_I2S_CTRL_TX_EN BIT(0)
#define AXI_I2S_CTRL_RX_EN BIT(1)
/* The frame size is configurable, but for now we always set it 64 bit */
#define AXI_I2S_BITS_PER_FRAME 64
struct axi_i2s {
struct regmap *regmap;
struct clk *clk;
struct clk *clk_ref;
struct snd_soc_dai_driver dai_driver;
struct snd_dmaengine_dai_dma_data capture_dma_data;
struct snd_dmaengine_dai_dma_data playback_dma_data;
struct snd_ratnum ratnum;
struct snd_pcm_hw_constraint_ratnums rate_constraints;
};
static int axi_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
unsigned int mask, val;
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
mask = AXI_I2S_CTRL_RX_EN;
else
mask = AXI_I2S_CTRL_TX_EN;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
val = mask;
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
val = 0;
break;
default:
return -EINVAL;
}
regmap_update_bits(i2s->regmap, AXI_I2S_REG_CTRL, mask, val);
return 0;
}
static int axi_i2s_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
unsigned int bclk_div, word_size;
unsigned int bclk_rate;
bclk_rate = params_rate(params) * AXI_I2S_BITS_PER_FRAME;
word_size = AXI_I2S_BITS_PER_FRAME / 2 - 1;
bclk_div = DIV_ROUND_UP(clk_get_rate(i2s->clk_ref), bclk_rate) / 2 - 1;
regmap_write(i2s->regmap, AXI_I2S_REG_CLK_CTRL, (word_size << 16) |
bclk_div);
return 0;
}
static int axi_i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
uint32_t mask;
int ret;
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
mask = AXI_I2S_RESET_RX_FIFO;
else
mask = AXI_I2S_RESET_TX_FIFO;
regmap_write(i2s->regmap, AXI_I2S_REG_RESET, mask);
ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
SNDRV_PCM_HW_PARAM_RATE,
&i2s->rate_constraints);
if (ret)
return ret;
return clk_prepare_enable(i2s->clk_ref);
}
static void axi_i2s_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
clk_disable_unprepare(i2s->clk_ref);
}
static int axi_i2s_dai_probe(struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);
snd_soc_dai_init_dma_data(dai, &i2s->playback_dma_data,
&i2s->capture_dma_data);
return 0;
}
static const struct snd_soc_dai_ops axi_i2s_dai_ops = {
.startup = axi_i2s_startup,
.shutdown = axi_i2s_shutdown,
.trigger = axi_i2s_trigger,
.hw_params = axi_i2s_hw_params,
};
static struct snd_soc_dai_driver axi_i2s_dai = {
.probe = axi_i2s_dai_probe,
.playback = {
.channels_min = 2,
.channels_max = 2,
.rates = SNDRV_PCM_RATE_KNOT,
.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
},
.capture = {
.channels_min = 2,
.channels_max = 2,
.rates = SNDRV_PCM_RATE_KNOT,
.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
},
.ops = &axi_i2s_dai_ops,
.symmetric_rates = 1,
};
static const struct snd_soc_component_driver axi_i2s_component = {
.name = "axi-i2s",
};
static const struct regmap_config axi_i2s_regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
.max_register = AXI_I2S_REG_STATUS,
};
static int axi_i2s_probe(struct platform_device *pdev)
{
struct resource *res;
struct axi_i2s *i2s;
void __iomem *base;
int ret;
i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
if (!i2s)
return -ENOMEM;
platform_set_drvdata(pdev, i2s);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_request_and_ioremap(&pdev->dev, res);
if (!base)
return -EBUSY;
i2s->regmap = devm_regmap_init_mmio(&pdev->dev, base,
&axi_i2s_regmap_config);
if (IS_ERR(i2s->regmap))
return PTR_ERR(i2s->regmap);
i2s->clk = devm_clk_get(&pdev->dev, "axi");
if (IS_ERR(i2s->clk))
return PTR_ERR(i2s->clk);
i2s->clk_ref = devm_clk_get(&pdev->dev, "ref");
if (IS_ERR(i2s->clk_ref))
return PTR_ERR(i2s->clk_ref);
ret = clk_prepare_enable(i2s->clk);
if (ret)
return ret;
i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
i2s->playback_dma_data.addr_width = 4;
i2s->playback_dma_data.maxburst = 1;
i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
i2s->capture_dma_data.addr_width = 4;
i2s->capture_dma_data.maxburst = 1;
i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME;
i2s->ratnum.den_step = 1;
i2s->ratnum.den_min = 1;
i2s->ratnum.den_max = 64;
i2s->rate_constraints.rats = &i2s->ratnum;
i2s->rate_constraints.nrats = 1;
regmap_write(i2s->regmap, AXI_I2S_REG_RESET, AXI_I2S_RESET_GLOBAL);
ret = devm_snd_soc_register_component(&pdev->dev, &axi_i2s_component,
&axi_i2s_dai, 1);
if (ret)
goto err_clk_disable;
ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL,
SND_DMAENGINE_PCM_FLAG_NO_RESIDUE);
if (ret)
goto err_clk_disable;
err_clk_disable:
clk_disable_unprepare(i2s->clk);
return ret;
}
static int axi_i2s_dev_remove(struct platform_device *pdev)
{
struct axi_i2s *i2s = platform_get_drvdata(pdev);
clk_disable_unprepare(i2s->clk);
return 0;
}
static const struct of_device_id axi_i2s_of_match[] = {
{ .compatible = "adi,axi-i2s-1.00.a", },
{},
};
MODULE_DEVICE_TABLE(of, axi_i2s_of_match);
static struct platform_driver axi_i2s_driver = {
.driver = {
.name = "axi-i2s",
.owner = THIS_MODULE,
.of_match_table = axi_i2s_of_match,
},
.probe = axi_i2s_probe,
.remove = axi_i2s_dev_remove,
};
module_platform_driver(axi_i2s_driver);
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("AXI I2S driver");
MODULE_LICENSE("GPL");