This was only used to allow modprobing i915, by converting to the
-EPROBE_DEFER mechanism, it can be completely removed, and is in
fact counterproductive since -EPROBE_DEFER otherwise won't be
handled correctly.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Matthew Auld <matthew.auld@intel.com>
---
 sound/soc/sof/Kconfig           | 19 -----------------
 sound/soc/sof/core.c            | 38 ++-------------------------------
 sound/soc/sof/intel/Kconfig     |  1 -
 sound/soc/sof/intel/hda-codec.c |  2 +-
 sound/soc/sof/intel/hda.c       | 32 ++++++++++++++++-----------
 sound/soc/sof/sof-pci-dev.c     |  3 +--
 sound/soc/sof/sof-priv.h        |  5 -----
 7 files changed, 23 insertions(+), 77 deletions(-)

diff --git a/sound/soc/sof/Kconfig b/sound/soc/sof/Kconfig
index 80361139a49ad..8ee39e5558062 100644
--- a/sound/soc/sof/Kconfig
+++ b/sound/soc/sof/Kconfig
@@ -82,17 +82,6 @@ config SND_SOC_SOF_DEVELOPER_SUPPORT
 
 if SND_SOC_SOF_DEVELOPER_SUPPORT
 
-config SND_SOC_SOF_FORCE_PROBE_WORKQUEUE
-	bool "SOF force probe workqueue"
-	select SND_SOC_SOF_PROBE_WORK_QUEUE
-	help
-	  This option forces the use of a probe workqueue, which is only used
-	  when HDaudio is enabled due to module dependencies. Forcing this
-	  option is intended for debug only, but this should not add any
-	  functional issues in nominal cases.
-	  Say Y if you are involved in SOF development and need this option.
-	  If not, select N.
-
 config SND_SOC_SOF_NOCODEC
 	tristate
 
@@ -271,14 +260,6 @@ config SND_SOC_SOF
 	  module dependencies but since the module or built-in type is decided
 	  at the top level it doesn't matter.
 
-config SND_SOC_SOF_PROBE_WORK_QUEUE
-	bool
-	help
-	  This option is not user-selectable but automagically handled by
-	  'select' statements at a higher level.
-	  When selected, the probe is handled in two steps, for example to
-	  avoid lockdeps if request_module is used in the probe.
-
 # Supported IPC versions
 config SND_SOC_SOF_IPC3
 	bool
diff --git a/sound/soc/sof/core.c b/sound/soc/sof/core.c
index 30db685cc5f4b..cdf86dc4a8a87 100644
--- a/sound/soc/sof/core.c
+++ b/sound/soc/sof/core.c
@@ -191,7 +191,8 @@ static int sof_probe_continue(struct snd_sof_dev *sdev)
 	/* probe the DSP hardware */
 	ret = snd_sof_probe(sdev);
 	if (ret < 0) {
-		dev_err(sdev->dev, "error: failed to probe DSP %d\n", ret);
+		if (ret != -EPROBE_DEFER)
+			dev_err(sdev->dev, "error: failed to probe DSP %d\n", ret);
 		goto probe_err;
 	}
 
@@ -309,8 +310,6 @@ static int sof_probe_continue(struct snd_sof_dev *sdev)
 	if (plat_data->sof_probe_complete)
 		plat_data->sof_probe_complete(sdev->dev);
 
-	sdev->probe_completed = true;
-
 	return 0;
 
 sof_machine_err:
@@ -336,19 +335,6 @@ static int sof_probe_continue(struct snd_sof_dev *sdev)
 	return ret;
 }
 
-static void sof_probe_work(struct work_struct *work)
-{
-	struct snd_sof_dev *sdev =
-		container_of(work, struct snd_sof_dev, probe_work);
-	int ret;
-
-	ret = sof_probe_continue(sdev);
-	if (ret < 0) {
-		/* errors cannot be propagated, log */
-		dev_err(sdev->dev, "error: %s failed err: %d\n", __func__, ret);
-	}
-}
-
 int snd_sof_device_probe(struct device *dev, struct snd_sof_pdata *plat_data)
 {
 	struct snd_sof_dev *sdev;
@@ -436,33 +422,16 @@ int snd_sof_device_probe(struct device *dev, struct snd_sof_pdata *plat_data)
 
 	sof_set_fw_state(sdev, SOF_FW_BOOT_NOT_STARTED);
 
-	if (IS_ENABLED(CONFIG_SND_SOC_SOF_PROBE_WORK_QUEUE)) {
-		INIT_WORK(&sdev->probe_work, sof_probe_work);
-		schedule_work(&sdev->probe_work);
-		return 0;
-	}
-
 	return sof_probe_continue(sdev);
 }
 EXPORT_SYMBOL(snd_sof_device_probe);
 
-bool snd_sof_device_probe_completed(struct device *dev)
-{
-	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
-
-	return sdev->probe_completed;
-}
-EXPORT_SYMBOL(snd_sof_device_probe_completed);
-
 int snd_sof_device_remove(struct device *dev)
 {
 	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
 	struct snd_sof_pdata *pdata = sdev->pdata;
 	int ret;
 
-	if (IS_ENABLED(CONFIG_SND_SOC_SOF_PROBE_WORK_QUEUE))
-		cancel_work_sync(&sdev->probe_work);
-
 	/*
 	 * Unregister any registered client device first before IPC and debugfs
 	 * to allow client drivers to be removed cleanly
@@ -501,9 +470,6 @@ int snd_sof_device_shutdown(struct device *dev)
 {
 	struct snd_sof_dev *sdev = dev_get_drvdata(dev);
 
-	if (IS_ENABLED(CONFIG_SND_SOC_SOF_PROBE_WORK_QUEUE))
-		cancel_work_sync(&sdev->probe_work);
-
 	if (sdev->fw_state == SOF_FW_BOOT_COMPLETE) {
 		sof_fw_trace_free(sdev);
 		return snd_sof_shutdown(sdev);
diff --git a/sound/soc/sof/intel/Kconfig b/sound/soc/sof/intel/Kconfig
index 69c1a370d3b61..d9e87a91670a3 100644
--- a/sound/soc/sof/intel/Kconfig
+++ b/sound/soc/sof/intel/Kconfig
@@ -293,7 +293,6 @@ config SND_SOC_SOF_HDA_LINK
 config SND_SOC_SOF_HDA_AUDIO_CODEC
 	bool "SOF support for HDAudio codecs"
 	depends on SND_SOC_SOF_HDA_LINK
-	select SND_SOC_SOF_PROBE_WORK_QUEUE
 	help
 	  This adds support for HDAudio codecs with Sound Open Firmware
 	  for Intel(R) platforms.
diff --git a/sound/soc/sof/intel/hda-codec.c b/sound/soc/sof/intel/hda-codec.c
index f1fd5b44aaac9..344b61576c0e3 100644
--- a/sound/soc/sof/intel/hda-codec.c
+++ b/sound/soc/sof/intel/hda-codec.c
@@ -415,7 +415,7 @@ int hda_codec_i915_init(struct snd_sof_dev *sdev)
 		return 0;
 
 	/* i915 exposes a HDA codec for HDMI audio */
-	ret = snd_hdac_i915_init(bus, true);
+	ret = snd_hdac_i915_init(bus, false);
 	if (ret < 0)
 		return ret;
 
diff --git a/sound/soc/sof/intel/hda.c b/sound/soc/sof/intel/hda.c
index 64bebe1a72bbc..a8b7a68142c05 100644
--- a/sound/soc/sof/intel/hda.c
+++ b/sound/soc/sof/intel/hda.c
@@ -801,8 +801,11 @@ static int hda_init(struct snd_sof_dev *sdev)
 
 	/* init i915 and HDMI codecs */
 	ret = hda_codec_i915_init(sdev);
-	if (ret < 0)
-		dev_warn(sdev->dev, "init of i915 and HDMI codec failed\n");
+	if (ret < 0) {
+		if (ret != -EPROBE_DEFER)
+			dev_warn(sdev->dev, "init of i915 and HDMI codec failed: %i\n", ret);
+		return ret;
+	}
 
 	/* get controller capabilities */
 	ret = hda_dsp_ctrl_get_caps(sdev);
@@ -1115,14 +1118,6 @@ int hda_dsp_probe(struct snd_sof_dev *sdev)
 	sdev->pdata->hw_pdata = hdev;
 	hdev->desc = chip;
 
-	hdev->dmic_dev = platform_device_register_data(sdev->dev, "dmic-codec",
-						       PLATFORM_DEVID_NONE,
-						       NULL, 0);
-	if (IS_ERR(hdev->dmic_dev)) {
-		dev_err(sdev->dev, "error: failed to create DMIC device\n");
-		return PTR_ERR(hdev->dmic_dev);
-	}
-
 	/*
 	 * use position update IPC if either it is forced
 	 * or we don't have other choice
@@ -1142,6 +1137,15 @@ int hda_dsp_probe(struct snd_sof_dev *sdev)
 	if (ret < 0)
 		goto hdac_bus_unmap;
 
+	hdev->dmic_dev = platform_device_register_data(sdev->dev, "dmic-codec",
+						       PLATFORM_DEVID_NONE,
+						       NULL, 0);
+	if (IS_ERR(hdev->dmic_dev)) {
+		dev_err(sdev->dev, "error: failed to create DMIC device\n");
+		ret = PTR_ERR(hdev->dmic_dev);
+		goto hdac_exit;
+	}
+
 	if (sdev->dspless_mode_selected)
 		goto skip_dsp_setup;
 
@@ -1150,7 +1154,7 @@ int hda_dsp_probe(struct snd_sof_dev *sdev)
 	if (!sdev->bar[HDA_DSP_BAR]) {
 		dev_err(sdev->dev, "error: ioremap error\n");
 		ret = -ENXIO;
-		goto hdac_bus_unmap;
+		goto platform_unreg;
 	}
 
 	sdev->mmio_bar = HDA_DSP_BAR;
@@ -1248,10 +1252,12 @@ int hda_dsp_probe(struct snd_sof_dev *sdev)
 /* dsp_unmap: not currently used */
 	if (!sdev->dspless_mode_selected)
 		iounmap(sdev->bar[HDA_DSP_BAR]);
-hdac_bus_unmap:
+platform_unreg:
 	platform_device_unregister(hdev->dmic_dev);
-	iounmap(bus->remap_addr);
+hdac_exit:
 	hda_codec_i915_exit(sdev);
+hdac_bus_unmap:
+	iounmap(bus->remap_addr);
 err:
 	return ret;
 }
diff --git a/sound/soc/sof/sof-pci-dev.c b/sound/soc/sof/sof-pci-dev.c
index f5ece43d0ec24..0fa424613082e 100644
--- a/sound/soc/sof/sof-pci-dev.c
+++ b/sound/soc/sof/sof-pci-dev.c
@@ -339,8 +339,7 @@ void sof_pci_remove(struct pci_dev *pci)
 	snd_sof_device_remove(&pci->dev);
 
 	/* follow recommendation in pci-driver.c to increment usage counter */
-	if (snd_sof_device_probe_completed(&pci->dev) &&
-	    !(sof_pci_debug & SOF_PCI_DISABLE_PM_RUNTIME))
+	if (!(sof_pci_debug & SOF_PCI_DISABLE_PM_RUNTIME))
 		pm_runtime_get_noresume(&pci->dev);
 
 	/* release pci regions and disable device */
diff --git a/sound/soc/sof/sof-priv.h b/sound/soc/sof/sof-priv.h
index d4f6702e93dcb..71db636cfdccc 100644
--- a/sound/soc/sof/sof-priv.h
+++ b/sound/soc/sof/sof-priv.h
@@ -564,10 +564,6 @@ struct snd_sof_dev {
 	enum sof_fw_state fw_state;
 	bool first_boot;
 
-	/* work queue in case the probe is implemented in two steps */
-	struct work_struct probe_work;
-	bool probe_completed;
-
 	/* DSP HW differentiation */
 	struct snd_sof_pdata *pdata;
 
@@ -675,7 +671,6 @@ struct snd_sof_dev {
 int snd_sof_device_probe(struct device *dev, struct snd_sof_pdata *plat_data);
 int snd_sof_device_remove(struct device *dev);
 int snd_sof_device_shutdown(struct device *dev);
-bool snd_sof_device_probe_completed(struct device *dev);
 
 int snd_sof_runtime_suspend(struct device *dev);
 int snd_sof_runtime_resume(struct device *dev);
-- 
2.39.2

On Tue, Jul 18, 2023 at 10:45:21AM +0200, Maarten Lankhorst wrote:
> This was only used to allow modprobing i915, by converting to the
> -EPROBE_DEFER mechanism, it can be completely removed, and is in
> fact counterproductive since -EPROBE_DEFER otherwise won't be
> handled correctly.

Acked-by: Mark Brown <broonie@kernel.org>

Hi,

thank you Maarten for doing the series! I think a lot of people will be 
happy to get rid of the 60sec timeout. 

I kicked off a CI run SOF public infra for the whole series at
https://github.com/thesofproject/linux/pull/4478
Some results still in progress but so far so good.

Some concerns inline:

On Tue, 18 Jul 2023, Maarten Lankhorst wrote:

> This was only used to allow modprobing i915, by converting to the
> -EPROBE_DEFER mechanism, it can be completely removed, and is in
> fact counterproductive since -EPROBE_DEFER otherwise won't be
> handled correctly.

We actually have a request_module() for the regular HDA codec drivers as 
well (sof_probe_continue() -> snd_sof_probe() -> hda_dsp_probe() -> 
hda_init_caps() -> hda_codec_probe_bus(). But right, this is not 
necessarily a problem on its own, so it looks we indeed can drop the work 
queue. Nice!

> diff --git a/sound/soc/sof/intel/hda-codec.c b/sound/soc/sof/intel/hda-codec.c
> index f1fd5b44aaac9..344b61576c0e3 100644
> --- a/sound/soc/sof/intel/hda-codec.c
> +++ b/sound/soc/sof/intel/hda-codec.c
> @@ -415,7 +415,7 @@ int hda_codec_i915_init(struct snd_sof_dev *sdev)
>  		return 0;
>  
>  	/* i915 exposes a HDA codec for HDMI audio */
> -	ret = snd_hdac_i915_init(bus, true);
> +	ret = snd_hdac_i915_init(bus, false);
>  	if (ret < 0)
>  		return ret;

My only bigger concern is corner cases where the display PCI device is on 
the bus and visible to kernel, but for some reason there is no working 
driver in the system or it is disabled.

With this patch, not having a workign display driver means that there is 
also no audio in the system as the SOF driver will never get probed.

In current mainline, one will get the 60sec timeout warning and then
audio driver will proceed to probe and you'll have audio support (minus 
HDMI/DP).

This is mostly an issue with very new hardware (e.g. hw is still 
behind force_probe flag in xe/i915 driver), but we've had some odd
cases with e.g. systems with both Intel IGFX and other vendors' DGPU. 
Audio drivers see the Intel VGA controller in system and will
call snd_hdac_i915_init(), but the audio component bind will never
succeed if the the Intel IGFX is not in actual use.

Will need a bit of time to think about possible scenarios. Possibly this 
is not an issue outside early development systems. In theory if IGFX is 
disabled in BIOS, and not visible to OS, we are good, and if it's visible, 
the i915/xe driver should be loaded, so we are good again.

Br, Kai

On Tue, 18 Jul 2023 19:04:41 +0200,
Kai Vehmanen wrote:
> 
> > diff --git a/sound/soc/sof/intel/hda-codec.c b/sound/soc/sof/intel/hda-codec.c
> > index f1fd5b44aaac9..344b61576c0e3 100644
> > --- a/sound/soc/sof/intel/hda-codec.c
> > +++ b/sound/soc/sof/intel/hda-codec.c
> > @@ -415,7 +415,7 @@ int hda_codec_i915_init(struct snd_sof_dev *sdev)
> >  		return 0;
> >  
> >  	/* i915 exposes a HDA codec for HDMI audio */
> > -	ret = snd_hdac_i915_init(bus, true);
> > +	ret = snd_hdac_i915_init(bus, false);
> >  	if (ret < 0)
> >  		return ret;
> 
> My only bigger concern is corner cases where the display PCI device is on 
> the bus and visible to kernel, but for some reason there is no working 
> driver in the system or it is disabled.
> 
> With this patch, not having a workign display driver means that there is 
> also no audio in the system as the SOF driver will never get probed.
> 
> In current mainline, one will get the 60sec timeout warning and then
> audio driver will proceed to probe and you'll have audio support (minus 
> HDMI/DP).

Yeah, that was a concern in the past, too.  e.g. when you pass
"nomodeset" boot option, the driver will become unusable, even if the
bus is used generically for both analog and HDMI codecs.

> This is mostly an issue with very new hardware (e.g. hw is still 
> behind force_probe flag in xe/i915 driver), but we've had some odd
> cases with e.g. systems with both Intel IGFX and other vendors' DGPU. 
> Audio drivers see the Intel VGA controller in system and will
> call snd_hdac_i915_init(), but the audio component bind will never
> succeed if the the Intel IGFX is not in actual use.
> 
> Will need a bit of time to think about possible scenarios. Possibly this 
> is not an issue outside early development systems. In theory if IGFX is 
> disabled in BIOS, and not visible to OS, we are good, and if it's visible, 
> the i915/xe driver should be loaded, so we are good again.

The 60 seconds timeout is a thing "better than complete disablement",
so it's not ideal, either.  Maybe we can add something like the
following:

- Check when the deferred probe takes too long, and warn it
- Provide some runtime option to disable the component binding, so
  that user can work around it if needed


thanks,

Takashi