linux-kernel - [PATCH v12 09/13] PCI: imx6: Turn off regulator when system is in suspend mode

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Date:   Wed, 15 Jun 2022 18:15:47 -0500
From:   Bjorn Helgaas <helgaas@...nel.org>
To:     Richard Zhu <hongxing.zhu@....com>,
        Lucas Stach <l.stach@...gutronix.de>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Brown <broonie@...nel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
        Fabio Estevam <festevam@...il.com>,
        Francesco Dolcini <francesco.dolcini@...adex.com>
Cc:     linux-pci@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, kernel@...gutronix.de,
        linux-imx@....com, Bjorn Helgaas <bhelgaas@...gle.com>
Subject: [PATCH v12 09/13] PCI: imx6: Turn off regulator when system is in suspend mode

From: Richard Zhu <hongxing.zhu@....com>

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://lore.kernel.org/r/1655189942-12678-6-git-send-email-hongxing.z
hu@....com
Signed-off-by: Richard Zhu <hongxing.zhu@....com>
Signed-off-by: Bjorn Helgaas <bhelgaas@...gle.com>
---
 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 6eddd0b5f628..537b8a2e0e3b 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, err;
 
-	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",
@@ -796,7 +786,7 @@ 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",
@@ -1023,6 +1013,9 @@ static int imx6_pcie_suspend_noirq(struct device *dev)
 		break;
 	}
 
+	if (imx6_pcie->vpcie)
+		regulator_disable(imx6_pcie->vpcie);
+
 	return 0;
 }
 
@@ -1269,6 +1262,8 @@ 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);
 }
 
 static const struct imx6_pcie_drvdata drvdata[] = {
-- 
2.25.1