[PATCH 4/4] snd/hda: add runtime suspend/resume on optimus support

[Takashi Iwai]

At Mon, 29 Jul 2013 16:06:59 +1000,
Dave Airlie wrote:
> 
> Add support for HDMI audio device on VGA cards that powerdown
> to D3cold using non-standard ACPI/PCI infrastructure (optimus).
> 
> This does a couple of things to make it work:
> 
> a) add a set of power ops for the hdmi domain, and enables them
> via vga_switcheroo when we are a switcheroo controlled card. This
> just replaces the runtime resume operation so that when the card
> is in D3cold the userspace pci config space access via sysfs,
> the vga switcheroon runtime resume gets called first and it calls
> the GPU resume callback before calling the sound card runtime
> resume.
> 
> b) standard ACPI/PCI stacks won't put a device into D3cold without
> an ACPI handle, but since the hdmi audio devices on gpus don't have
> an ACPI handle, we need to manually force the device into D3cold
> after suspend from the switcheroo path only.
> 
> c) don't try and do runtime s/r when the GPU is off.
> 
> d) call runtime suspend/resume during switcheroo suspend/resume
> this is to make sure the runtime stack knows to try and resume
> the hdmi audio device for pci config space access.
> 
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>  sound/pci/hda/hda_intel.c | 40 +++++++++++++++++++++++++++++++++++++---
>  1 file changed, 37 insertions(+), 3 deletions(-)
> 
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index 8860dd5..4b4d05b 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -555,6 +555,9 @@ struct azx {
>  #ifdef CONFIG_SND_HDA_DSP_LOADER
>  	struct azx_dev saved_azx_dev;
>  #endif
> +
> +	/* secondary power domain for hdmi audio under vga device */
> +	struct dev_pm_domain hdmi_pm_domain;
>  };
>  
>  #define CREATE_TRACE_POINTS
> @@ -2898,7 +2901,7 @@ static int param_set_xint(const char *val, const struct kernel_param *kp)
>  /*
>   * power management
>   */
> -static int azx_suspend(struct device *dev)
> +static int azx_do_suspend(struct device *dev, pci_power_t state)
>  {
>  	struct pci_dev *pci = to_pci_dev(dev);
>  	struct snd_card *card = dev_get_drvdata(dev);
> @@ -2920,16 +2923,30 @@ static int azx_suspend(struct device *dev)
>  		free_irq(chip->irq, chip);
>  		chip->irq = -1;
>  	}
> +
> +	/*
> +	 * for vga switcheroo suspend we need to
> +	 * force runtime suspend so lspci works.
> +	 */
> +	if (state == PCI_D3cold)
> +		pm_runtime_suspend(&pci->dev);
> +
>  	if (chip->msi)
>  		pci_disable_msi(chip->pci);
>  	pci_disable_device(pci);
>  	pci_save_state(pci);
> -	pci_set_power_state(pci, PCI_D3hot);
> +
> +	pci_set_power_state(pci, state);
>  	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
>  		hda_display_power(false);
>  	return 0;
>  }
>  
> +static int azx_suspend(struct device *dev)
> +{
> +	return azx_do_suspend(dev, PCI_D3hot);
> +}
> +
>  static int azx_resume(struct device *dev)
>  {
>  	struct pci_dev *pci = to_pci_dev(dev);
> @@ -2971,6 +2988,9 @@ static int azx_runtime_suspend(struct device *dev)
>  	struct snd_card *card = dev_get_drvdata(dev);
>  	struct azx *chip = card->private_data;
>  
> +	if (chip->disabled)
> +		return 0;
> +
>  	azx_stop_chip(chip);
>  	azx_enter_link_reset(chip);
>  	azx_clear_irq_pending(chip);
> @@ -2984,6 +3004,9 @@ static int azx_runtime_resume(struct device *dev)
>  	struct snd_card *card = dev_get_drvdata(dev);
>  	struct azx *chip = card->private_data;
>  
> +	if (chip->disabled)
> +		return 0;
> +
>  	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
>  		hda_display_power(true);
>  	azx_init_pci(chip);
> @@ -2996,6 +3019,9 @@ static int azx_runtime_idle(struct device *dev)
>  	struct snd_card *card = dev_get_drvdata(dev);
>  	struct azx *chip = card->private_data;
>  
> +	if (chip->disabled)
> +		return 0;
> +
>  	if (!power_save_controller ||
>  	    !(chip->driver_caps & AZX_DCAPS_PM_RUNTIME))
>  		return -EBUSY;
> @@ -3078,7 +3104,11 @@ static void azx_vs_set_state(struct pci_dev *pci,
>  			   "%s: %s via VGA-switcheroo\n", pci_name(chip->pci),
>  			   disabled ? "Disabling" : "Enabling");
>  		if (disabled) {
> -			azx_suspend(&pci->dev);
> +			azx_do_suspend(&pci->dev, PCI_D3cold);
> +			/* when we get suspended by vga switcheroo we end up in D3cold,
> +			 * however we have no ACPI handle, so pci/acpi can't put us there,
> +			 * put ourselves there */
> +			pci->current_state = PCI_D3cold;
>  			chip->disabled = true;
>  			if (snd_hda_lock_devices(chip->bus))
>  				snd_printk(KERN_WARNING SFX "%s: Cannot lock devices!\n",
> @@ -3087,6 +3117,7 @@ static void azx_vs_set_state(struct pci_dev *pci,
>  			snd_hda_unlock_devices(chip->bus);
>  			chip->disabled = false;
>  			azx_resume(&pci->dev);
> +			pm_runtime_suspend(&pci->dev);

Is this meant as pm_runtime_resume()?


thanks,

Takashi

>  		}
>  	}
>  }
> @@ -3139,6 +3170,9 @@ static int register_vga_switcheroo(struct azx *chip)
>  	if (err < 0)
>  		return err;
>  	chip->vga_switcheroo_registered = 1;
> +
> +	/* register as an optimus hdmi audio power domain */
> +	vga_switcheroo_init_domain_pm_optimus_hdmi_audio(&chip->pci->dev, &chip->hdmi_pm_domain);
>  	return 0;
>  }
>  #else
> -- 
> 1.8.2.1
> 
>