On Mon, 07 Oct 2019 20:49:56 +0200, Kai-Heng Feng wrote: > > Hi Takashi, > > > On Sep 25, 2019, at 19:32, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote: > > > > Nvidia proprietary driver doesn't support runtime power management, so > > when a user only wants to use the integrated GPU, it's a common practice > > to let dGPU not to bind any driver, and let its upstream port to be > > runtime suspended. At the end of runtime suspension the port uses > > platform power management to disable power through _OFF method of power > > resource, which is listed by _PR3. > > > > After commit b516ea586d71 ("PCI: Enable NVIDIA HDA controllers"), when > > the dGPU comes with an HDA function, the HDA won't be suspended if the > > dGPU is unbound, so the power resource can't be turned off by its > > upstream port driver. > > > > Commit 37a3a98ef601 ("ALSA: hda - Enable runtime PM only for > > discrete GPU") only allows HDA to be runtime suspended once GPU is > > bound, to keep APU's HDA working. > > > > However, HDA on dGPU isn't that useful if dGPU is not bound to any > > driver. So let's relax the runtime suspend requirement for dGPU's HDA > > function, to disable the power source to save lots of power. > > > > BugLink: https://bugs.launchpad.net/bugs/1840835 > > Fixes: b516ea586d71 ("PCI: Enable NVIDIA HDA controllers") > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > > Do you still have any concern on this patch? > Please merge [v5 1/2] and this patch [v4 2/2] if you think it's good. Sorry for the late reply, as I've been off for a few weeks. Now I applied both patches for 5.4. Thanks! Takashi > > Thanks! > > Kai-Heng > > > --- > > v4: > > - Find upstream port, it's callee's responsibility now. > > v3: > > - Make changelog more clear. > > v2: > > - Change wording. > > - Rebase to Tiwai's branch. > > sound/pci/hda/hda_intel.c | 8 +++++++- > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c > > index 240f4ca76391..e63b871343e5 100644 > > --- a/sound/pci/hda/hda_intel.c > > +++ b/sound/pci/hda/hda_intel.c > > @@ -1280,11 +1280,17 @@ static void init_vga_switcheroo(struct azx *chip) > > { > > struct hda_intel *hda = container_of(chip, struct hda_intel, chip); > > struct pci_dev *p = get_bound_vga(chip->pci); > > + struct pci_dev *parent; > > if (p) { > > dev_info(chip->card->dev, > > "Handle vga_switcheroo audio client\n"); > > hda->use_vga_switcheroo = 1; > > - chip->bus.keep_power = 1; /* cleared in either gpu_bound op or codec probe */ > > + > > + /* cleared in either gpu_bound op or codec probe, or when its > > + * upstream port has _PR3 (i.e. dGPU). > > + */ > > + parent = pci_upstream_bridge(p); > > + chip->bus.keep_power = parent ? !pci_pr3_present(parent) : 1; > > chip->driver_caps |= AZX_DCAPS_PM_RUNTIME; > > pci_dev_put(p); > > } > > -- > > 2.17.1 > > > > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel