> -----Original Message----- > From: Lucas Stach <l.stach@xxxxxxxxxxxxxx> > Sent: 2022年7月13日 16:34 > To: Hongxing Zhu <hongxing.zhu@xxxxxxx>; bhelgaas@xxxxxxxxxx; > robh+dt@xxxxxxxxxx; broonie@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx; > festevam@xxxxxxxxx; francesco.dolcini@xxxxxxxxxxx > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > linux-kernel@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; dl-linux-imx > <linux-imx@xxxxxxx> > Subject: Re: [PATCH v14 10/17] PCI: imx6: Turn off regulator when system is in > suspend mode > > Am Freitag, dem 01.07.2022 um 11:25 +0800 schrieb Richard Zhu: > > The driver should undo any enables it did itself. The regulator > > disable shouldn't be basing decisions on regulator_is_enabled(). > > > > Move the regulator_disable to the suspend function, turn off regulator > > when the system is in suspend mode. > > > > To keep the balance of the regulator usage counter, disable the > > regulator in shutdown. > > > > Link: > > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore > > .kernel.org%2Fr%2F1655189942-12678-6-git-send-email-hongxing.z&d > at > > > a=05%7C01%7Chongxing.zhu%40nxp.com%7C361c9bf365b64895482808da6 > 4aa7cca% > > > 7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6379329806385373 > 39%7CUnkn > > > own%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1 > haWwi > > > LCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=A%2Fw6AFCddC0T%2FA > ocBT%2F7OJZ > > ddAeYPTbgeAxpHpPubkw%3D&reserved=0 > > hu@xxxxxxx > > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx> > > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > --- > > drivers/pci/controller/dwc/pci-imx6.c | 19 +++++++------------ > > 1 file changed, 7 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c > > b/drivers/pci/controller/dwc/pci-imx6.c > > index 2b42c37f1617..f72eb609769b 100644 > > --- a/drivers/pci/controller/dwc/pci-imx6.c > > +++ b/drivers/pci/controller/dwc/pci-imx6.c > > @@ -670,8 +670,6 @@ static void imx6_pcie_clk_disable(struct imx6_pcie > > *imx6_pcie) > > > > static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie) > > { > > - struct device *dev = imx6_pcie->pci->dev; > > - > > switch (imx6_pcie->drvdata->variant) { > > case IMX7D: > > case IMX8MQ: > > @@ -702,14 +700,6 @@ static void imx6_pcie_assert_core_reset(struct > imx6_pcie *imx6_pcie) > > break; > > } > > > > - if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { > > - int ret = regulator_disable(imx6_pcie->vpcie); > > - > > - if (ret) > > - dev_err(dev, "failed to disable vpcie regulator: %d\n", > > - ret); > > - } > > - > > /* Some boards don't have PCIe reset GPIO. */ > > if (gpio_is_valid(imx6_pcie->reset_gpio)) > > gpio_set_value_cansleep(imx6_pcie->reset_gpio, > > @@ -722,7 +712,7 @@ static int imx6_pcie_deassert_core_reset(struct > imx6_pcie *imx6_pcie) > > struct device *dev = pci->dev; > > int ret; > > > > - if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) { > > + if (imx6_pcie->vpcie) { > > ret = regulator_enable(imx6_pcie->vpcie); > > if (ret) { > > dev_err(dev, "failed to enable vpcie regulator: %d\n", > > The regulator really has nothing to do with the core reset. Please move this > regulator enable into imx6_pcie_host_init(). Hi Lucas: Thanks for your comments. Got that. Had done it in the 11/17 commit. > > > @@ -795,7 +785,7 @@ static int imx6_pcie_deassert_core_reset(struct > imx6_pcie *imx6_pcie) > > return 0; > > > > err_clks: > > - if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) { > > + if (imx6_pcie->vpcie) { > > ret = regulator_disable(imx6_pcie->vpcie); > > if (ret) > > dev_err(dev, "failed to disable vpcie regulator: %d\n", @@ > -1022,6 > > +1012,9 @@ static int imx6_pcie_suspend_noirq(struct device *dev) > > break; > > } > > > > + if (imx6_pcie->vpcie) > > + regulator_disable(imx6_pcie->vpcie); > > + > > return 0; > > } > > > > @@ -1268,6 +1261,8 @@ static void imx6_pcie_shutdown(struct > > platform_device *pdev) > > > > /* bring down link, so bootloader gets clean state in case of reboot */ > > imx6_pcie_assert_core_reset(imx6_pcie); > > + if (imx6_pcie->vpcie) > > + regulator_disable(imx6_pcie->vpcie); > > This looks like a separate change, not mentioned in the commit message. > I'm not sure if we should do this. Shutdown is supposed to just stop the device, > which is already achieved by imx6_pcie_assert_core_reset(). > > If we would want to do a full cleanup here we would also need to disable > clocks and get the reset GPIO into asserted state. I don't think we want to do > all of this here. The regulator_disable() was contained in imx6_pcie_assert_core_reset() before. When refine the regulator usage, the regulator_disable() is moved out of imx6_pcie_assert_core_reset(). Based on the discussion [1] with Francesco. To keep the same behavior, the regulator_disable() is placed behind of imx6_pcie_assert_core_reset() in imx6_pcie_shutdown() here. [1]https://patchwork.ozlabs.org/project/linux-pci/patch/1644290735-3797-6-git-send-email-hongxing.zhu@xxxxxxx/ Best Regards Richard > > Regards, > Lucas > > } > > > > static const struct imx6_pcie_drvdata drvdata[] = { >
