[PATCH] ASoC: omap-abe-twl6040: Correct dmic-codec device registration

From: Peter Ujfalusi
Date: Fri Aug 19 2016 - 02:34:24 EST


The dmic-codec was registered within the platform_driver's probe function,
which can cause deferred probe to run in loops as reported and analyzed by
Russell King.

Use module_init/exit in the driver and handle the dmic-codec device
registration and removal at that level instead of the platform_driver
probe/remove.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Reported-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Tested-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/omap/omap-abe-twl6040.c | 61 ++++++++++++++++++++-------------------
1 file changed, 32 insertions(+), 29 deletions(-)

diff --git a/sound/soc/omap/omap-abe-twl6040.c b/sound/soc/omap/omap-abe-twl6040.c
index 0843a68f277c..f61b3b58083b 100644
--- a/sound/soc/omap/omap-abe-twl6040.c
+++ b/sound/soc/omap/omap-abe-twl6040.c
@@ -38,10 +38,10 @@
struct abe_twl6040 {
int jack_detection; /* board can detect jack events */
int mclk_freq; /* MCLK frequency speed for twl6040 */
-
- struct platform_device *dmic_codec_dev;
};

+struct platform_device *dmic_codec_dev;
+
static int omap_abe_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
@@ -258,8 +258,6 @@ static int omap_abe_probe(struct platform_device *pdev)
if (priv == NULL)
return -ENOMEM;

- priv->dmic_codec_dev = ERR_PTR(-EINVAL);
-
if (snd_soc_of_parse_card_name(card, "ti,model")) {
dev_err(&pdev->dev, "Card name is not provided\n");
return -ENODEV;
@@ -284,13 +282,6 @@ static int omap_abe_probe(struct platform_device *pdev)
num_links = 2;
abe_twl6040_dai_links[1].cpu_of_node = dai_node;
abe_twl6040_dai_links[1].platform_of_node = dai_node;
-
- priv->dmic_codec_dev = platform_device_register_simple(
- "dmic-codec", -1, NULL, 0);
- if (IS_ERR(priv->dmic_codec_dev)) {
- dev_err(&pdev->dev, "Can't instantiate dmic-codec\n");
- return PTR_ERR(priv->dmic_codec_dev);
- }
} else {
num_links = 1;
}
@@ -299,16 +290,14 @@ static int omap_abe_probe(struct platform_device *pdev)
of_property_read_u32(node, "ti,mclk-freq", &priv->mclk_freq);
if (!priv->mclk_freq) {
dev_err(&pdev->dev, "MCLK frequency not provided\n");
- ret = -EINVAL;
- goto err_unregister;
+ return -EINVAL;
}

card->fully_routed = 1;

if (!priv->mclk_freq) {
dev_err(&pdev->dev, "MCLK frequency missing\n");
- ret = -ENODEV;
- goto err_unregister;
+ return -ENODEV;
}

card->dai_link = abe_twl6040_dai_links;
@@ -317,17 +306,9 @@ static int omap_abe_probe(struct platform_device *pdev)
snd_soc_card_set_drvdata(card, priv);

ret = snd_soc_register_card(card);
- if (ret) {
+ if (ret)
dev_err(&pdev->dev, "snd_soc_register_card() failed: %d\n",
ret);
- goto err_unregister;
- }
-
- return 0;
-
-err_unregister:
- if (!IS_ERR(priv->dmic_codec_dev))
- platform_device_unregister(priv->dmic_codec_dev);

return ret;
}
@@ -335,13 +316,9 @@ err_unregister:
static int omap_abe_remove(struct platform_device *pdev)
{
struct snd_soc_card *card = platform_get_drvdata(pdev);
- struct abe_twl6040 *priv = snd_soc_card_get_drvdata(card);

snd_soc_unregister_card(card);

- if (!IS_ERR(priv->dmic_codec_dev))
- platform_device_unregister(priv->dmic_codec_dev);
-
return 0;
}

@@ -361,7 +338,33 @@ static struct platform_driver omap_abe_driver = {
.remove = omap_abe_remove,
};

-module_platform_driver(omap_abe_driver);
+static int __init omap_abe_init(void)
+{
+ int ret;
+
+ dmic_codec_dev = platform_device_register_simple("dmic-codec", -1, NULL,
+ 0);
+ if (IS_ERR(dmic_codec_dev)) {
+ pr_err("%s: dmic-codec device registration failed\n", __func__);
+ return PTR_ERR(dmic_codec_dev);
+ }
+
+ ret = platform_driver_register(&omap_abe_driver);
+ if (ret) {
+ pr_err("%s: platform driver registration failed\n", __func__);
+ platform_device_unregister(dmic_codec_dev);
+ }
+
+ return ret;
+}
+module_init(omap_abe_init);
+
+static void __exit omap_abe_exit(void)
+{
+ platform_driver_unregister(&omap_abe_driver);
+ platform_device_unregister(dmic_codec_dev);
+}
+module_exit(omap_abe_exit);

MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@xxxxxx>");
MODULE_DESCRIPTION("ALSA SoC for OMAP boards with ABE and twl6040 codec");
--
2.8.1