[alsa-devel] [PATCH 1/2] ASoC: Prevent components from being bound to multiple cards
A component can only be bound to a single card at a time. Binding it to card while it is already bound to another will result in undefined behavior.
As the undefined behavior might only manifest itself later on it is not necessarily always straight forward to find the cause. To prevent this add a check that refuses to bind a component to multiple cards as well as prints a error describing the problem.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de --- sound/soc/soc-core.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 8baf87d..d9ae826 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -1104,9 +1104,19 @@ static int soc_probe_component(struct snd_soc_card *card, struct snd_soc_dai *dai; int ret;
- if (!strcmp(component->name, "snd-soc-dummy") || component->probed) + if (!strcmp(component->name, "snd-soc-dummy")) return 0;
+ if (component->probed) { + if (component->card != card) { + dev_err(component->dev, + "Trying to bind component to card "%s" but is already bound to card "%s"\n", + card->name, component->card->name); + return -ENODEV; + } + return 0; + } + component->card = card; dapm->card = card; soc_set_name_prefix(card, component);
Use the card field of a component to indicate whether it is bound or not. This makes a certain sense given that the field contains the card the component is bound to and a component can only be bound to one card at a time. And it also requires to unset the card field when the component is unbound from the card.
This makes the probded flag redundant and it can be removed.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de --- include/sound/soc.h | 1 - sound/soc/soc-core.c | 16 ++++++++-------- 2 files changed, 8 insertions(+), 9 deletions(-)
diff --git a/include/sound/soc.h b/include/sound/soc.h index 3ccd82a..ab69e26 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -758,7 +758,6 @@ struct snd_soc_component {
unsigned int ignore_pmdown_time:1; /* pmdown_time is ignored at stop */ unsigned int registered_as_component:1; - unsigned int probed:1;
struct list_head list;
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index d9ae826..2fc461c 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -980,7 +980,7 @@ static int soc_bind_dai_link(struct snd_soc_card *card, int num)
static void soc_remove_component(struct snd_soc_component *component) { - if (!component->probed) + if (!component->card) return;
/* This is a HACK and will be removed soon */ @@ -993,7 +993,7 @@ static void soc_remove_component(struct snd_soc_component *component) snd_soc_dapm_free(snd_soc_component_get_dapm(component));
soc_cleanup_component_debugfs(component); - component->probed = 0; + component->card = NULL; module_put(component->dev->driver->owner); }
@@ -1107,7 +1107,7 @@ static int soc_probe_component(struct snd_soc_card *card, if (!strcmp(component->name, "snd-soc-dummy")) return 0;
- if (component->probed) { + if (component->card) { if (component->card != card) { dev_err(component->dev, "Trying to bind component to card "%s" but is already bound to card "%s"\n", @@ -1117,13 +1117,13 @@ static int soc_probe_component(struct snd_soc_card *card, return 0; }
+ if (!try_module_get(component->dev->driver->owner)) + return -ENODEV; + component->card = card; dapm->card = card; soc_set_name_prefix(card, component);
- if (!try_module_get(component->dev->driver->owner)) - return -ENODEV; - soc_init_component_debugfs(component);
if (component->dapm_widgets) { @@ -1167,7 +1167,6 @@ static int soc_probe_component(struct snd_soc_card *card, snd_soc_dapm_add_routes(dapm, component->dapm_routes, component->num_dapm_routes);
- component->probed = 1; list_add(&dapm->list, &card->dapm_list);
/* This is a HACK and will be removed soon */ @@ -1178,6 +1177,7 @@ static int soc_probe_component(struct snd_soc_card *card,
err_probe: soc_cleanup_component_debugfs(component); + component->card = NULL; module_put(component->dev->driver->owner);
return ret; @@ -1461,7 +1461,7 @@ static void soc_remove_aux_dev(struct snd_soc_card *card, int num) rtd->dev_registered = 0; }
- if (component && component->probed) + if (component) soc_remove_component(component); }
On Wed, Jul 08, 2015 at 08:47:44PM +0200, Lars-Peter Clausen wrote:
Use the card field of a component to indicate whether it is bound or not. This makes a certain sense given that the field contains the card the component is bound to and a component can only be bound to one card at a time. And it also requires to unset the card field when the component is unbound from the card.
This makes the probded flag redundant and it can be removed.
Right, this is just a leftover from when we used to open code our own deferred probing at this point.
The patch
ASoC: Use card field to indicate whether a component is bound
has been applied to the asoc tree at
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
From abd31b32dde4683df6fd0439caa314aafd751698 Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen lars@metafoo.de Date: Wed, 8 Jul 2015 20:47:44 +0200 Subject: [PATCH] ASoC: Use card field to indicate whether a component is bound
Use the card field of a component to indicate whether it is bound or not. This makes a certain sense given that the field contains the card the component is bound to and a component can only be bound to one card at a time. And it also requires to unset the card field when the component is unbound from the card.
This makes the probded flag redundant and it can be removed.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de Signed-off-by: Mark Brown broonie@kernel.org --- include/sound/soc.h | 1 - sound/soc/soc-core.c | 16 ++++++++-------- 2 files changed, 8 insertions(+), 9 deletions(-)
diff --git a/include/sound/soc.h b/include/sound/soc.h index 93df8bf9d54a..59635a12c3be 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -758,7 +758,6 @@ struct snd_soc_component {
unsigned int ignore_pmdown_time:1; /* pmdown_time is ignored at stop */ unsigned int registered_as_component:1; - unsigned int probed:1;
struct list_head list;
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 96bb71aea529..42575b03411e 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -978,7 +978,7 @@ static int soc_bind_dai_link(struct snd_soc_card *card, int num)
static void soc_remove_component(struct snd_soc_component *component) { - if (!component->probed) + if (!component->card) return;
/* This is a HACK and will be removed soon */ @@ -991,7 +991,7 @@ static void soc_remove_component(struct snd_soc_component *component) snd_soc_dapm_free(snd_soc_component_get_dapm(component));
soc_cleanup_component_debugfs(component); - component->probed = 0; + component->card = NULL; module_put(component->dev->driver->owner); }
@@ -1105,7 +1105,7 @@ static int soc_probe_component(struct snd_soc_card *card, if (!strcmp(component->name, "snd-soc-dummy")) return 0;
- if (component->probed) { + if (component->card) { if (component->card != card) { dev_err(component->dev, "Trying to bind component to card "%s" but is already bound to card "%s"\n", @@ -1115,13 +1115,13 @@ static int soc_probe_component(struct snd_soc_card *card, return 0; }
+ if (!try_module_get(component->dev->driver->owner)) + return -ENODEV; + component->card = card; dapm->card = card; soc_set_name_prefix(card, component);
- if (!try_module_get(component->dev->driver->owner)) - return -ENODEV; - soc_init_component_debugfs(component);
if (component->dapm_widgets) { @@ -1165,7 +1165,6 @@ static int soc_probe_component(struct snd_soc_card *card, snd_soc_dapm_add_routes(dapm, component->dapm_routes, component->num_dapm_routes);
- component->probed = 1; list_add(&dapm->list, &card->dapm_list);
/* This is a HACK and will be removed soon */ @@ -1176,6 +1175,7 @@ static int soc_probe_component(struct snd_soc_card *card,
err_probe: soc_cleanup_component_debugfs(component); + component->card = NULL; module_put(component->dev->driver->owner);
return ret; @@ -1459,7 +1459,7 @@ static void soc_remove_aux_dev(struct snd_soc_card *card, int num) rtd->dev_registered = 0; }
- if (component && component->probed) + if (component) soc_remove_component(component); }
The patch
ASoC: Prevent components from being bound to multiple cards
has been applied to the asoc tree at
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
From 1b7c12316982f74a5b8e7704c24cf5524d0723a3 Mon Sep 17 00:00:00 2001
From: Lars-Peter Clausen lars@metafoo.de Date: Wed, 8 Jul 2015 20:47:43 +0200 Subject: [PATCH] ASoC: Prevent components from being bound to multiple cards
A component can only be bound to a single card at a time. Binding it to card while it is already bound to another will result in undefined behavior.
As the undefined behavior might only manifest itself later on it is not necessarily always straight forward to find the cause. To prevent this add a check that refuses to bind a component to multiple cards as well as prints a error describing the problem.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/soc-core.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 6ce621749f8d..96bb71aea529 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -1102,9 +1102,19 @@ static int soc_probe_component(struct snd_soc_card *card, struct snd_soc_dai *dai; int ret;
- if (!strcmp(component->name, "snd-soc-dummy") || component->probed) + if (!strcmp(component->name, "snd-soc-dummy")) return 0;
+ if (component->probed) { + if (component->card != card) { + dev_err(component->dev, + "Trying to bind component to card "%s" but is already bound to card "%s"\n", + card->name, component->card->name); + return -ENODEV; + } + return 0; + } + component->card = card; dapm->card = card; soc_set_name_prefix(card, component);
participants (2)
-
Lars-Peter Clausen -
Mark Brown