| Message ID | 20200214134704.342501-1-jbrunet@baylibre.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | b2354e4009a773c00054b964d937e1b81cb92078 |
| Headers | show |
| Series | [RFC] ASoC: core: ensure component names are unique | expand |
On Fri 14 Feb 2020 at 21:56, Mark Brown <broonie@kernel.org> wrote: > The patch > > ASoC: core: ensure component names are unique > > has been applied to the asoc tree at > > https://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 Hi Mark, Short Version: After looking at the problem reported by Marek, I think the best course of action for now is to revert b2354e4009a7 ("ASoC: core: ensure component names are unique") while working on a solution. It might take some time. Longer Version: 1) Multiple components : I found out that in fact it is common for linux devices to register multiple components. For most, it is a combination of the dmaengine generic and the actual device component, but other register more component. Ex: - vc4-hdmi - atmel-classd - atmel-pdmic - cros-ec-codec - mtXXXX-afe-pcm I suspect these trigger the debugfs warning Even dummy register two components :D All devices using devm_snd_dmaengine_pcm_register() and devm_snd_soc_register_component() are exposed to clean-up issue in case of deferral. That's because snd_soc_unregister_component() unregisters all the components registered the device. I suppose there might be other problems when using the devm API with this function. 2) Fixed component names: Several card driver assume the component name is the device name and won't query the actual component name or node. Ex: - sun4i-codec - omap-hdmi - vc4-hdmi - sof-nocodec So changing the way ASoC generate the component names might break these cards. It gets tricky because the same cards driver might register multiple component themselves, like vc4-hdmi. > > From b2354e4009a773c00054b964d937e1b81cb92078 Mon Sep 17 00:00:00 2001 > From: Jerome Brunet <jbrunet@baylibre.com> > Date: Fri, 14 Feb 2020 14:47:04 +0100 > Subject: [PATCH] ASoC: core: ensure component names are unique > > Make sure each ASoC component is registered with a unique name. > The component is derived from the device name. If a device registers more > than one component, the component names will be the same. > > This usually brings up a warning about the debugfs directory creation of > the component since directory already exists. > > In such case, start numbering the component of the device so the names > don't collide anymore. > > Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> > Link: https://lore.kernel.org/r/20200214134704.342501-1-jbrunet@baylibre.com > Signed-off-by: Mark Brown <broonie@kernel.org> > --- > sound/soc/soc-core.c | 29 ++++++++++++++++++++++++++++- > 1 file changed, 28 insertions(+), 1 deletion(-) > > diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c > index 03b87427faa7..6a58a8f6e3c4 100644 > --- a/sound/soc/soc-core.c > +++ b/sound/soc/soc-core.c > @@ -2446,6 +2446,33 @@ static int snd_soc_register_dais(struct snd_soc_component *component, > return ret; > } > > +static char *snd_soc_component_unique_name(struct device *dev, > + struct snd_soc_component *component) > +{ > + struct snd_soc_component *pos; > + int count = 0; > + char *name, *unique; > + > + name = fmt_single_name(dev, &component->id); > + if (!name) > + return name; > + > + /* Count the number of components registred by the device */ > + for_each_component(pos) { > + if (dev == pos->dev) > + count++; > + } > + > + /* Keep naming as it is for the 1st component */ > + if (!count) > + return name; > + > + unique = devm_kasprintf(dev, GFP_KERNEL, "%s-%d", name, count); > + devm_kfree(dev, name); > + > + return unique; > +} > + > static int snd_soc_component_initialize(struct snd_soc_component *component, > const struct snd_soc_component_driver *driver, struct device *dev) > { > @@ -2454,7 +2481,7 @@ static int snd_soc_component_initialize(struct snd_soc_component *component, > INIT_LIST_HEAD(&component->card_list); > mutex_init(&component->io_mutex); > > - component->name = fmt_single_name(dev, &component->id); > + component->name = snd_soc_component_unique_name(dev, component); > if (!component->name) { > dev_err(dev, "ASoC: Failed to allocate name\n"); > return -ENOMEM;
On Tue, Feb 18, 2020 at 07:55:31PM +0100, Jerome Brunet wrote: > 1) Multiple components : > I found out that in fact it is common for linux devices to register > multiple components. For most, it is a combination of the dmaengine > generic and the actual device component, but other register more > component. Ex: > - vc4-hdmi > - atmel-classd > - atmel-pdmic > - cros-ec-codec > - mtXXXX-afe-pcm > I suspect these trigger the debugfs warning > Even dummy register two components :D I hadn't realized we have so many - I'd have expected the debugfs complaints would've been noticable to people, I was hoping based on the initial discussion that it was just a couple of quick fixed needed. Guess not :/ Anyway, I agree that a revert is probably sensible for the time being and getting this done is more involved - can you send patches doing the revert with a changelog explaining the rationale please?
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 03b87427faa7..6a58a8f6e3c4 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -2446,6 +2446,33 @@ static int snd_soc_register_dais(struct snd_soc_component *component, return ret; } +static char *snd_soc_component_unique_name(struct device *dev, + struct snd_soc_component *component) +{ + struct snd_soc_component *pos; + int count = 0; + char *name, *unique; + + name = fmt_single_name(dev, &component->id); + if (!name) + return name; + + /* Count the number of components registred by the device */ + for_each_component(pos) { + if (dev == pos->dev) + count++; + } + + /* Keep naming as it is for the 1st component */ + if (!count) + return name; + + unique = devm_kasprintf(dev, GFP_KERNEL, "%s-%d", name, count); + devm_kfree(dev, name); + + return unique; +} + static int snd_soc_component_initialize(struct snd_soc_component *component, const struct snd_soc_component_driver *driver, struct device *dev) { @@ -2454,7 +2481,7 @@ static int snd_soc_component_initialize(struct snd_soc_component *component, INIT_LIST_HEAD(&component->card_list); mutex_init(&component->io_mutex); - component->name = fmt_single_name(dev, &component->id); + component->name = snd_soc_component_unique_name(dev, component); if (!component->name) { dev_err(dev, "ASoC: Failed to allocate name\n"); return -ENOMEM;
Make sure each ASoC component is registered with a unique name. The component is derived from the device name. If a device registers more than one component, the component names will be the same. This usually brings up a warning about the debugfs directory creation of the component since directory already exists. In such case, start numbering the component of the device so the names don't collide anymore. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> --- * Here is an example of /sys/kernel/debug/asoc/components before the change: hdmi-audio-codec.3.auto c1105400.audio-controller c1105400.audio-controller c1105400.audio-controller c8832000.audio-controller analog-amplifier snd-soc-dummy snd-soc-dummy * and after: hdmi-audio-codec.3.auto c1105400.audio-controller-2 c1105400.audio-controller-1 c1105400.audio-controller c8832000.audio-controller analog-amplifier snd-soc-dummy-1 snd-soc-dummy I wanted to keep the name as they were for the devices registering only one component but we could also start the numbering from the first component instead of the second. sound/soc/soc-core.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-)