linux/sound/soc/fsl/imx-spdif.c
Nicolin Chen 14c3aa9839 ASoC: imx-spdif: Use snd-soc-dummy CODEC driver to link card
This is a quick fix for the below two issues when building spdif as modules.

1) If modprobing modules in order: (Step 1) snd-soc-fsl-spdif -> (Step 2)
snd-soc-imx-spdif -> (Step 3) snd-soc-spdif-tx/rx, we will fail to create
imx-spdif card and dai link unless we rmmod snd-soc-imx-spdif and modprobe
it again due to the execution platform_driver_unregister() in probe() when
meeting -EPROBE_DEFER at Step 2.

2) After "imx-spdif sound-spdif.17: dit-hifi <-> 2004000.spdif mapping ok",
'rmmod snd-soc-imx-spdif' would cause kernel dump with warning:
WARNING: CPU: 0 PID: 1301 at /home/rmk/git/linux-rmk/fs/sysfs/dir.c:915 sysfs_hash_and_remove+0x84/0x90()
sysfs: can not remove 'dapm_widget', no directory
This should be caused by disordered resourse releasing of the whole link.
And trying to unregister the card and then CODEC dev can't fix this issue.

Thus this patch just provides a simple fix to these two bugs by using the
snd-soc-dummy in the core instead of seperate snd-soc-spdif-tx/rx so that
there's no need to handle the registering and unregistering of CODEC or
CODEC dai any more.

Signed-off-by: Nicolin Chen <Guangyu.Chen@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
2013-12-31 16:32:37 +00:00

105 lines
2.5 KiB
C

/*
* Copyright (C) 2013 Freescale Semiconductor, Inc.
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/module.h>
#include <linux/of_platform.h>
#include <sound/soc.h>
struct imx_spdif_data {
struct snd_soc_dai_link dai;
struct snd_soc_card card;
};
static int imx_spdif_audio_probe(struct platform_device *pdev)
{
struct device_node *spdif_np, *np = pdev->dev.of_node;
struct imx_spdif_data *data;
int ret = 0;
spdif_np = of_parse_phandle(np, "spdif-controller", 0);
if (!spdif_np) {
dev_err(&pdev->dev, "failed to find spdif-controller\n");
ret = -EINVAL;
goto end;
}
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data) {
dev_err(&pdev->dev, "failed to allocate memory\n");
ret = -ENOMEM;
goto end;
}
data->dai.name = "S/PDIF PCM";
data->dai.stream_name = "S/PDIF PCM";
data->dai.codec_dai_name = "snd-soc-dummy-dai";
data->dai.codec_name = "snd-soc-dummy";
data->dai.cpu_of_node = spdif_np;
data->dai.platform_of_node = spdif_np;
data->dai.playback_only = true;
data->dai.capture_only = true;
if (of_property_read_bool(np, "spdif-out"))
data->dai.capture_only = false;
if (of_property_read_bool(np, "spdif-in"))
data->dai.playback_only = false;
if (data->dai.playback_only && data->dai.capture_only) {
dev_err(&pdev->dev, "no enabled S/PDIF DAI link\n");
goto end;
}
data->card.dev = &pdev->dev;
data->card.dai_link = &data->dai;
data->card.num_links = 1;
ret = snd_soc_of_parse_card_name(&data->card, "model");
if (ret)
goto end;
ret = devm_snd_soc_register_card(&pdev->dev, &data->card);
if (ret) {
dev_err(&pdev->dev, "snd_soc_register_card failed: %d\n", ret);
goto end;
}
platform_set_drvdata(pdev, data);
end:
if (spdif_np)
of_node_put(spdif_np);
return ret;
}
static const struct of_device_id imx_spdif_dt_ids[] = {
{ .compatible = "fsl,imx-audio-spdif", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, imx_spdif_dt_ids);
static struct platform_driver imx_spdif_driver = {
.driver = {
.name = "imx-spdif",
.owner = THIS_MODULE,
.of_match_table = imx_spdif_dt_ids,
},
.probe = imx_spdif_audio_probe,
};
module_platform_driver(imx_spdif_driver);
MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Freescale i.MX S/PDIF machine driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:imx-spdif");