Thread (16 messages) 16 messages, 2 authors, 2022-02-24
STALE1572d
Revisions (8)
  1. v2 [diff vs current]
  2. v3 [diff vs current]
  3. v4 [diff vs current]
  4. v5 [diff vs current]
  5. v6 [diff vs current]
  6. v7 current
  7. v8 [diff vs current]
  8. v9 [diff vs current]

[PATCH v7 5/8] PCI: imx6: Refine the regulator usage

From: Richard Zhu <hongxing.zhu@nxp.com>
Date: 2022-02-16 07:07:22
Also in: linux-pci, lkml
Subsystem: pci driver for imx6, pci native host bridge and endpoint drivers, pci subsystem, the rest · Maintainers: Richard Zhu, Lucas Stach, Lorenzo Pieralisi, Krzysztof Wilczyński, Manivannan Sadhasivam, Bjorn Helgaas, Linus Torvalds

The driver should undo any enables it did itself. The regulator disable
shouldn't be basing decisions on regulator_is_enabled().

To keep the balance of the regulator usage counter, disable the regulator
just behind of imx6_pcie_assert_core_reset() in resume and shutdown.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.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 0aca762d88a3..242d8ef73c1e 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -369,8 +369,6 @@ static int imx6_pcie_attach_pd(struct device *dev)
 
 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:
@@ -400,14 +398,6 @@ static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
 				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
 		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);
-	}
 }
 
 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
@@ -583,7 +573,7 @@ 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",
@@ -656,7 +646,7 @@ 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",
@@ -1028,6 +1018,9 @@ static int imx6_pcie_resume_noirq(struct device *dev)
 		return 0;
 
 	imx6_pcie_assert_core_reset(imx6_pcie);
+	if (imx6_pcie->vpcie)
+		regulator_disable(imx6_pcie->vpcie);
+
 	imx6_pcie_init_phy(imx6_pcie);
 	imx6_pcie_deassert_core_reset(imx6_pcie);
 	dw_pcie_setup_rc(pp);
@@ -1261,6 +1254,8 @@ 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


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