[alsa-devel] [PATCH 2/2] vgaswitchreoo: set audio client id in vgaswitchreoo enable function

[Takashi Iwai]

On Fri, 13 Jul 2018 10:06:02 +0200,
Jim Qu wrote:
> 
> On modern laptop, there are more and more platforms
> have two GPUs, and each of them maybe have audio codec
> for HDMP/DP output. For some dGPU which is no output,
> audio codec usually is disabled.
> 
> In currect HDA audio driver, it will set all codec as
> VGA_SWITCHEROO_DIS, the audio which is binded to UMA
> will be suspended if user use debugfs to contorl power
> 
> In HDA driver side, it is difficult to know which GPU
> the audio has binded to. So set the bound gpu pci dev
> to vgaswitchroo, the correct audio id will be set in
> vgaswitchreoo enable function.
> 
> Signed-off-by: Jim Qu <Jim.Qu at amd.com>

The idea looks good to me.  Just a nitpick:

> @@ -1319,15 +1319,16 @@ static const struct vga_switcheroo_client_ops azx_vs_ops = {
>  static int register_vga_switcheroo(struct azx *chip)
>  {
>  	struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
> +	struct pci_dev * p;
>  	int err;
>  
>  	if (!hda->use_vga_switcheroo)
>  		return 0;
> -	/* FIXME: currently only handling DIS controller
> -	 * is there any machine with two switchable HDMI audio controllers?
> -	 */
> -	err = vga_switcheroo_register_audio_client(chip->pci, &azx_vs_ops,
> -						   VGA_SWITCHEROO_DIS);
> +
> +	p  = get_bound_vga(chip->pci);
> +	err = vga_switcheroo_register_audio_client(chip->pci, &azx_vs_ops, p);
> +	if (p)
> +		pci_dev_put(p);

Passing a NULL vga_dev won't work, so the NULL check after calling
vga_switcheroo_register_audio_client() is moot.  If any, it should be
checked before that.


thanks,

Takashi