[alsa-devel] [PATCH] ASoC: imx-spdif: Use module_init() to handle platform_device_register()
Nicolin Chen
Guangyu.Chen at freescale.com
Mon Dec 16 11:36:09 CET 2013
This is a quick fix for the below two issues when building spdif as modules.
1) When modprobing modules in order: snd-soc-fsl-spdif -> snd-soc-imx-spdif
-> 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 inappropriate
condition of platform_driver_unregister() in probe().
2) After "imx-spdif sound-spdif.17: dit-hifi <-> 2004000.spdif mapping ok",
doing rmmod the imx-spdif would cause kernel Oops:
------------[ cut here ]------------
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
Modules linked in: snd_soc_imx_spdif(-) snd_soc_fsl_spdif imx_pcm_dma fuse bnep rfcomm bluetooth imx_sdma imx_thermal imx2_wdt snd_soc_spdif_tx hid_cypress [last unloaded: imx_pcm_dma]
CPU: 0 PID: 1301 Comm: rmmod Not tainted 3.13.0-rc4+ #387
Backtrace:
[<c0012640>] (dump_backtrace) from [<c00127dc>] (show_stack+0x18/0x1c)
r6:00000393 r5:c016bfa4 r4:00000000 r3:00000000
[<c00127c4>] (show_stack) from [<c0683a18>] (dump_stack+0x70/0x90)
[<c06839a8>] (dump_stack) from [<c00244e0>] (warn_slowpath_common+0x74/0x94)
r4:dab89d30 r3:00000000
[<c002446c>] (warn_slowpath_common) from [<c00245a4>] (warn_slowpath_fmt+0x38/0x40)
r8:c689ce00 r7:00000000 r6:00000000 r5:c077c04c r4:dba2a318
[<c0024570>] (warn_slowpath_fmt) from [<c016bfa4>] (sysfs_hash_and_remove+0x84/0x90)
r3:c077c04c r2:c06b3c38
[<c016bf20>] (sysfs_hash_and_remove) from [<c016a00c>] (sysfs_remove_file_ns+0x18/0x1c)
r7:da916900 r6:00000000 r5:db2c900c r4:dba2a318
[<c0169ff4>] (sysfs_remove_file_ns) from [<c03687d4>] (device_remove_file+0x20/0x24)
[<c03687b4>] (device_remove_file) from [<c04f532c>] (snd_soc_dapm_free+0x1c/0x22c)
[<c04f5310>] (snd_soc_dapm_free) from [<c04f0c98>] (soc_remove_codec+0x34/0x98)
r10:dabae59c r9:00000000 r8:c689ce00 r7:da916900 r6:00000000 r5:db2c900c
r4:dba2a200 r3:00000000
[<c04f0c64>] (soc_remove_codec) from [<c04f3188>] (soc_remove_dai_links.clone.28+0x3c0/0x3ec)
r4:00000000 r3:00000000
[<c04f2dc8>] (soc_remove_dai_links.clone.28) from [<c04f3248>] (snd_soc_unregister_card+0x94/0xc8)
r10:d8435000 r9:db924204 r8:d8435000 r7:d079d480 r6:00000001 r5:00000608
r4:dabae4b8
[<c04f31b4>] (snd_soc_unregister_card) from [<c04ffa70>] (devm_card_release+0x14/0x18)
r6:00000003 r5:db924010 r4:dab89e60 r3:c04ffa5c
[<c04ffa5c>] (devm_card_release) from [<c036ec74>] (release_nodes+0x190/0x1f8)
[<c036eae4>] (release_nodes) from [<c036ed94>] (devres_release_all+0x38/0x54)
r10:00000000 r9:dab88000 r8:c000eb44 r7:bef87600 r6:db924044 r5:bf131014
r4:db924010
[<c036ed5c>] (devres_release_all) from [<c036b7a8>] (__device_release_driver+0x80/0xd4)
r4:db924010 r3:bf12f000
[<c036b728>] (__device_release_driver) from [<c036bf28>] (driver_detach+0xbc/0xc0)
r5:bf131014 r4:db924010
[<c036be6c>] (driver_detach) from [<c036b490>] (bus_remove_driver+0x54/0x98)
r6:dab89f3c r5:bf131058 r4:bf131014 r3:db0c8000
[<c036b43c>] (bus_remove_driver) from [<c036c588>] (driver_unregister+0x30/0x4c)
r4:bf131014 r3:c68a7a80
[<c036c558>] (driver_unregister) from [<c036d21c>] (platform_driver_unregister+0x14/0x18)
r4:00000000 r3:bf12f2d0
[<c036d208>] (platform_driver_unregister) from [<bf12f2e4>] (imx_spdif_driver_exit+0x14/0xd30 [snd_soc_imx_spdif])
[<bf12f2d0>] (imx_spdif_driver_exit [snd_soc_imx_spdif]) from [<c008d764>] (SyS_delete_module+0x140/0x190)
[<c008d624>] (SyS_delete_module) from [<c000e980>] (ret_fast_syscall+0x0/0x48)
r7:00000081 r6:000120a8 r5:bef87600 r4:00000880
---[ end trace 09423e64ab60df46 ]---
Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = dab9c000
[00000008] *pgd=2062f831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in: snd_soc_imx_spdif(-) snd_soc_fsl_spdif imx_pcm_dma fuse bnep rfcomm bluetooth imx_sdma imx_thermal imx2_wdt snd_soc_spdif_tx hid_cypress [last unloaded: imx_pcm_dma]
CPU: 0 PID: 1301 Comm: rmmod Tainted: G W 3.13.0-rc4+ #387
task: db0c8000 ti: dab88000 task.ti: dab88000
PC is at soc_remove_codec+0x78/0x98
LR is at trace_hardirqs_on+0x14/0x18
pc : [<c04f0cdc>] lr : [<c0066514>] psr: 600f0013
sp : dab89dc8 ip : 00000020 fp : dab89ddc
r10: dabae59c r9 : 00000000 r8 : c689ce00
r7 : da916900 r6 : 00000000 r5 : db2c900c r4 : dba2a200
r3 : 00000000 r2 : 00100100 r1 : dabac810 r0 : dabae5f8
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 10c53c7d Table: 2ab9c059 DAC: 00000015
Process rmmod (pid: 1301, stack limit = 0xdab88240)
Stack: (0xdab89dc8 to 0xdab8a000)
9dc0: 00000000 00000000 dab89e24 dab89de0 c04f3188 c04f0c70
9de0: d84355bc dabae5a0 00200200 00100100 00200200 00100100 d079d480 dabae4b8
9e00: 00000608 00000001 d079d480 d8435000 db924204 d8435000 dab89e44 dab89e28
9e20: c04f3248 c04f2dd4 c04ffa5c dab89e60 db924010 00000003 dab89e54 dab89e48
9e40: c04ffa70 c04f31c0 dab89e94 dab89e58 c036ec74 c04ffa68 dab89e94 a00f0013
9e60: dabae400 d079d480 00000002 db924010 bf131014 db924044 bef87600 c000eb44
9e80: dab88000 00000000 dab89eac dab89e98 c036ed94 c036eaf0 bf12f000 db924010
9ea0: dab89ec4 dab89eb0 c036b7a8 c036ed68 db924010 bf131014 dab89ee4 dab89ec8
9ec0: c036bf28 c036b734 db0c8000 bf131014 bf131058 dab89f3c dab89efc dab89ee8
9ee0: c036b490 c036be78 c68a7a80 bf131014 dab89f14 dab89f00 c036c588 c036b448
9f00: bf12f2d0 00000000 dab89f24 dab89f18 c036d21c c036c564 dab89f34 dab89f28
9f20: bf12f2e4 c036d214 dab89fa4 dab89f38 c008d764 bf12f2dc 00000000 5f646e73
9f40: 5f636f73 5f786d69 69647073 bef80066 dab89f74 dab89f60 c005f0d4 c0069020
9f60: 0077a008 00000000 00000880 bef87600 000120a8 00000081 bf131058 00000880
9f80: dab89f84 00000000 00000880 bef87600 000120a8 00000081 00000000 dab89fa8
9fa0: c000e980 c008d630 00000880 bef87600 bef87600 00000880 00009778 bef875f4
9fc0: 00000880 bef87600 000120a8 00000081 00000001 000120bc 00000001 00000000
9fe0: b6f03840 bef875fc 00008f75 b6f0384c 800f0010 bef87600 00000000 00000000
Backtrace:
[<c04f0c64>] (soc_remove_codec) from [<c04f3188>] (soc_remove_dai_links.clone.28+0x3c0/0x3ec)
r4:00000000 r3:00000000
[<c04f2dc8>] (soc_remove_dai_links.clone.28) from [<c04f3248>] (snd_soc_unregister_card+0x94/0xc8)
r10:d8435000 r9:db924204 r8:d8435000 r7:d079d480 r6:00000001 r5:00000608
r4:dabae4b8
[<c04f31b4>] (snd_soc_unregister_card) from [<c04ffa70>] (devm_card_release+0x14/0x18)
r6:00000003 r5:db924010 r4:dab89e60 r3:c04ffa5c
[<c04ffa5c>] (devm_card_release) from [<c036ec74>] (release_nodes+0x190/0x1f8)
[<c036eae4>] (release_nodes) from [<c036ed94>] (devres_release_all+0x38/0x54)
r10:00000000 r9:dab88000 r8:c000eb44 r7:bef87600 r6:db924044 r5:bf131014
r4:db924010
[<c036ed5c>] (devres_release_all) from [<c036b7a8>] (__device_release_driver+0x80/0xd4)
r4:db924010 r3:bf12f000
[<c036b728>] (__device_release_driver) from [<c036bf28>] (driver_detach+0xbc/0xc0)
r5:bf131014 r4:db924010
[<c036be6c>] (driver_detach) from [<c036b490>] (bus_remove_driver+0x54/0x98)
r6:dab89f3c r5:bf131058 r4:bf131014 r3:db0c8000
[<c036b43c>] (bus_remove_driver) from [<c036c588>] (driver_unregister+0x30/0x4c)
r4:bf131014 r3:c68a7a80
[<c036c558>] (driver_unregister) from [<c036d21c>] (platform_driver_unregister+0x14/0x18)
r4:00000000 r3:bf12f2d0
[<c036d208>] (platform_driver_unregister) from [<bf12f2e4>] (imx_spdif_driver_exit+0x14/0xd30 [snd_soc_imx_spdif])
[<bf12f2d0>] (imx_spdif_driver_exit [snd_soc_imx_spdif]) from [<c008d764>] (SyS_delete_module+0x140/0x190)
[<c008d624>] (SyS_delete_module) from [<c000e980>] (ret_fast_syscall+0x0/0x48)
r7:00000081 r6:000120a8 r5:bef87600 r4:00000880
Code: e594100c e5842068 e584306c e5913080 (e5930008)
---[ end trace 09423e64ab60df47 ]---
Ideally, we should bypass the device_unregister() if getting EPROBE_DEFER,
and find the root cause of "can not remove 'dapm_widget', no directory".
But the root cause seems to be beyond the imx-spdif driver level, which
might be related to the disordered resource releasing of the whole link.
Thus this patch can provide a quick fix, if acceptable, to these two bugs
so that the driver can finely work when being built as modules. And it's
also safe enough to avoid duplicate regisitering/unregistering since we
don't handle them in the probe() and remove() any more. At the meantime,
we can trace the root cause of the Oops without pressure.
Test report:
root at freescale ~$ modprobe snd-soc-spdif-rx
imx-spdif sound-spdif.10: dir-hifi <-> 2004000.spdif mapping ok
root at freescale ~$ rmmod snd-soc-imx-spdif
root at freescale ~$ modprobe snd-soc-imx-spdif
imx-spdif sound-spdif.10: dir-hifi <-> 2004000.spdif mapping ok
root at freescale ~$ rmmod snd-soc-imx-spdif
root at freescale ~$ rmmod snd-soc-fsl-spdif
root at freescale ~$ modprobe snd-soc-imx-spdif
imx-spdif sound-spdif.10: ASoC: CPU DAI (null) not registered
imx-spdif sound-spdif.10: snd_soc_register_card failed: -517
platform sound-spdif.10: Driver imx-spdif requests probe deferral
root at freescale ~$ modprobe snd-soc-fsl-spdif
imx-spdif sound-spdif.10: dir-hifi <-> 2004000.spdif mapping ok
root at freescale ~$ rmmod snd-soc-imx-spdif
root at freescale ~$ rmmod snd-soc-spdif-rx
root at freescale ~$ modprobe snd-soc-imx-spdif
imx-spdif sound-spdif.10: ASoC: CODEC spdif-dir not registered
imx-spdif sound-spdif.10: snd_soc_register_card failed: -517
platform sound-spdif.10: Driver imx-spdif requests probe deferral
root at freescale ~$ modprobe snd-soc-spdif-rx
imx-spdif sound-spdif.10: dir-hifi <-> 2004000.spdif mapping ok
Reported-by: Russell King <linux at arm.linux.org.uk>
Signed-off-by: Nicolin Chen <Guangyu.Chen at freescale.com>
---
sound/soc/fsl/imx-spdif.c | 84 ++++++++++++++++++++++++-----------------------
1 file changed, 43 insertions(+), 41 deletions(-)
diff --git a/sound/soc/fsl/imx-spdif.c b/sound/soc/fsl/imx-spdif.c
index 980dd1f..c4b9894 100644
--- a/sound/soc/fsl/imx-spdif.c
+++ b/sound/soc/fsl/imx-spdif.c
@@ -16,8 +16,6 @@
struct imx_spdif_data {
struct snd_soc_dai_link dai[2];
struct snd_soc_card card;
- struct platform_device *txdev;
- struct platform_device *rxdev;
};
static int imx_spdif_audio_probe(struct platform_device *pdev)
@@ -47,13 +45,6 @@ static int imx_spdif_audio_probe(struct platform_device *pdev)
data->dai[num_links].cpu_of_node = spdif_np;
data->dai[num_links].platform_of_node = spdif_np;
num_links++;
-
- data->txdev = platform_device_register_simple("spdif-dit", -1, NULL, 0);
- if (IS_ERR(data->txdev)) {
- ret = PTR_ERR(data->txdev);
- dev_err(&pdev->dev, "register dit failed: %d\n", ret);
- goto end;
- }
}
if (of_property_read_bool(np, "spdif-in")) {
@@ -64,18 +55,11 @@ static int imx_spdif_audio_probe(struct platform_device *pdev)
data->dai[num_links].cpu_of_node = spdif_np;
data->dai[num_links].platform_of_node = spdif_np;
num_links++;
-
- data->rxdev = platform_device_register_simple("spdif-dir", -1, NULL, 0);
- if (IS_ERR(data->rxdev)) {
- ret = PTR_ERR(data->rxdev);
- dev_err(&pdev->dev, "register dir failed: %d\n", ret);
- goto error_dit;
- }
}
if (!num_links) {
dev_err(&pdev->dev, "no enabled S/PDIF DAI link\n");
- goto error_dir;
+ goto end;
}
data->card.dev = &pdev->dev;
@@ -84,24 +68,16 @@ static int imx_spdif_audio_probe(struct platform_device *pdev)
ret = snd_soc_of_parse_card_name(&data->card, "model");
if (ret)
- goto error_dir;
+ 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 error_dir;
+ goto end;
}
platform_set_drvdata(pdev, data);
- goto end;
-
-error_dir:
- if (data->rxdev)
- platform_device_unregister(data->rxdev);
-error_dit:
- if (data->txdev)
- platform_device_unregister(data->txdev);
end:
if (spdif_np)
of_node_put(spdif_np);
@@ -109,18 +85,6 @@ end:
return ret;
}
-static int imx_spdif_audio_remove(struct platform_device *pdev)
-{
- struct imx_spdif_data *data = platform_get_drvdata(pdev);
-
- if (data->rxdev)
- platform_device_unregister(data->rxdev);
- if (data->txdev)
- platform_device_unregister(data->txdev);
-
- return 0;
-}
-
static const struct of_device_id imx_spdif_dt_ids[] = {
{ .compatible = "fsl,imx-audio-spdif", },
{ /* sentinel */ }
@@ -134,10 +98,48 @@ static struct platform_driver imx_spdif_driver = {
.of_match_table = imx_spdif_dt_ids,
},
.probe = imx_spdif_audio_probe,
- .remove = imx_spdif_audio_remove,
};
-module_platform_driver(imx_spdif_driver);
+static struct platform_device *txdev;
+static struct platform_device *rxdev;
+
+static int __init imx_spdif_init(void)
+{
+ int ret;
+
+ txdev = platform_device_register_simple("spdif-dit", -1, NULL, 0);
+ if (IS_ERR(txdev))
+ return PTR_ERR(txdev);
+
+ rxdev = platform_device_register_simple("spdif-dir", -1, NULL, 0);
+ if (IS_ERR(rxdev)) {
+ ret = PTR_ERR(rxdev);
+ goto err;
+ }
+
+ ret = platform_driver_register(&imx_spdif_driver);
+ if (ret)
+ goto err1;
+
+ return 0;
+
+err1:
+ platform_device_unregister(rxdev);
+err:
+ platform_device_unregister(txdev);
+
+ return ret;
+}
+module_init(imx_spdif_init);
+
+static void __exit imx_spdif_exit(void)
+{
+ platform_driver_unregister(&imx_spdif_driver);
+
+ platform_device_unregister(rxdev);
+ platform_device_unregister(txdev);
+}
+module_exit(imx_spdif_exit);
MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Freescale i.MX S/PDIF machine driver");
--
1.8.4
More information about the Alsa-devel
mailing list