diff mbox series

[v15,17/17] PCI: imx6: Reformat suspend callback to keep symmetric with resume

Message ID 1657783869-19194-18-git-send-email-hongxing.zhu@nxp.com (mailing list archive)
State Accepted
Headers show
Series PCI: imx6: refine codes and add the error propagation | expand

Commit Message

Richard Zhu July 14, 2022, 7:31 a.m. UTC 
Create imx6_pcie_stop_link() and imx6_pcie_host_exit() functions.
Encapsulate clocks, regulators disables and PHY uninitialization into
imx6_pcie_host_exit().

To keep suspend/resume symmetric as much as possible, invoke these two
new created functions in suspend callback.

To be symmetric with imx6_pcie_host_exit(), move imx6_pcie_clk_enable()
to imx6_pcie_host_init() from imx6_pcie_deassert_core_reset().

Link: https://lore.kernel.org/r/1656645935-1370-18-git-send-email-hongxing.zhu@nxp.com
Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
---
 drivers/pci/controller/dwc/pci-imx6.c | 62 ++++++++++++++++-----------
 1 file changed, 37 insertions(+), 25 deletions(-)

Comments

Guenter Roeck July 18, 2022, 1:19 p.m. UTC | #1 
On Thu, Jul 14, 2022 at 03:31:09PM +0800, Richard Zhu wrote:
> Create imx6_pcie_stop_link() and imx6_pcie_host_exit() functions.
> Encapsulate clocks, regulators disables and PHY uninitialization into
> imx6_pcie_host_exit().
> 
> To keep suspend/resume symmetric as much as possible, invoke these two
> new created functions in suspend callback.
> 
> To be symmetric with imx6_pcie_host_exit(), move imx6_pcie_clk_enable()
> to imx6_pcie_host_init() from imx6_pcie_deassert_core_reset().
> 
> Link: https://lore.kernel.org/r/1656645935-1370-18-git-send-email-hongxing.zhu@nxp.com
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

If CONFIG_PM_SLEEP=n:

Error log:
drivers/pci/controller/dwc/pci-imx6.c:973:13: error: 'imx6_pcie_host_exit' defined but not used [-Werror=unused-function]
  973 | static void imx6_pcie_host_exit(struct dw_pcie_rp *pp)
      |             ^~~~~~~~~~~~~~~~~~~
drivers/pci/controller/dwc/pci-imx6.c:904:13: error: 'imx6_pcie_stop_link' defined but not used [-Werror=unused-function]
  904 | static void imx6_pcie_stop_link(struct dw_pcie *pci)

Guenter
Bjorn Helgaas July 19, 2022, 11:10 p.m. UTC | #2 
On Mon, Jul 18, 2022 at 06:19:00AM -0700, Guenter Roeck wrote:
> On Thu, Jul 14, 2022 at 03:31:09PM +0800, Richard Zhu wrote:
> > Create imx6_pcie_stop_link() and imx6_pcie_host_exit() functions.
> > Encapsulate clocks, regulators disables and PHY uninitialization into
> > imx6_pcie_host_exit().
> > 
> > To keep suspend/resume symmetric as much as possible, invoke these two
> > new created functions in suspend callback.
> > 
> > To be symmetric with imx6_pcie_host_exit(), move imx6_pcie_clk_enable()
> > to imx6_pcie_host_init() from imx6_pcie_deassert_core_reset().
> > 
> > Link: https://lore.kernel.org/r/1656645935-1370-18-git-send-email-hongxing.zhu@nxp.com
> > Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> > Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
> 
> If CONFIG_PM_SLEEP=n:
> 
> Error log:
> drivers/pci/controller/dwc/pci-imx6.c:973:13: error: 'imx6_pcie_host_exit' defined but not used [-Werror=unused-function]
>   973 | static void imx6_pcie_host_exit(struct dw_pcie_rp *pp)
>       |             ^~~~~~~~~~~~~~~~~~~
> drivers/pci/controller/dwc/pci-imx6.c:904:13: error: 'imx6_pcie_stop_link' defined but not used [-Werror=unused-function]
>   904 | static void imx6_pcie_stop_link(struct dw_pcie *pci)

Thanks, Guenter, I added a patch that should fix this:
https://lore.kernel.org/r/20220719210427.GA1568454@bhelgaas
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 21e9101f63f0..b7a7e3465f28 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -703,13 +703,6 @@  static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
 {
 	struct dw_pcie *pci = imx6_pcie->pci;
 	struct device *dev = pci->dev;
-	int ret;
-
-	ret = imx6_pcie_clk_enable(imx6_pcie);
-	if (ret) {
-		dev_err(dev, "unable to enable pcie clocks: %d\n", ret);
-		return ret;
-	}
 
 	switch (imx6_pcie->drvdata->variant) {
 	case IMX8MQ:
@@ -904,6 +897,14 @@  static int imx6_pcie_start_link(struct dw_pcie *pci)
 	return 0;
 }
 
+static void imx6_pcie_stop_link(struct dw_pcie *pci)
+{
+	struct device *dev = pci->dev;
+
+	/* Turn off PCIe LTSSM */
+	imx6_pcie_ltssm_disable(dev);
+}
+
 static int imx6_pcie_host_init(struct pcie_port *pp)
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
@@ -923,11 +924,17 @@  static int imx6_pcie_host_init(struct pcie_port *pp)
 	imx6_pcie_assert_core_reset(imx6_pcie);
 	imx6_pcie_init_phy(imx6_pcie);
 
+	ret = imx6_pcie_clk_enable(imx6_pcie);
+	if (ret) {
+		dev_err(dev, "unable to enable pcie clocks: %d\n", ret);
+		goto err_reg_disable;
+	}
+
 	if (imx6_pcie->phy) {
 		ret = phy_power_on(imx6_pcie->phy);
 		if (ret) {
 			dev_err(dev, "pcie phy power up failed\n");
-			goto err_reg_disable;
+			goto err_clk_disable;
 		}
 	}
 
@@ -941,24 +948,40 @@  static int imx6_pcie_host_init(struct pcie_port *pp)
 		ret = phy_init(imx6_pcie->phy);
 		if (ret) {
 			dev_err(dev, "waiting for phy ready timeout!\n");
-			goto err_clk_disable;
+			goto err_phy_off;
 		}
 	}
 	imx6_setup_phy_mpll(imx6_pcie);
 
 	return 0;
 
-err_clk_disable:
-	imx6_pcie_clk_disable(imx6_pcie);
 err_phy_off:
 	if (imx6_pcie->phy)
 		phy_power_off(imx6_pcie->phy);
+err_clk_disable:
+	imx6_pcie_clk_disable(imx6_pcie);
 err_reg_disable:
 	if (imx6_pcie->vpcie)
 		regulator_disable(imx6_pcie->vpcie);
 	return ret;
 }
 
+static void imx6_pcie_host_exit(struct pcie_port *pp)
+{
+	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
+
+	if (imx6_pcie->phy) {
+		if (phy_power_off(imx6_pcie->phy))
+			dev_err(pci->dev, "unable to power off PHY\n");
+		phy_exit(imx6_pcie->phy);
+	}
+	imx6_pcie_clk_disable(imx6_pcie);
+
+	if (imx6_pcie->vpcie)
+		regulator_disable(imx6_pcie->vpcie);
+}
+
 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
 	.host_init = imx6_pcie_host_init,
 };
@@ -1008,25 +1031,14 @@  static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
 static int imx6_pcie_suspend_noirq(struct device *dev)
 {
 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
+	struct pcie_port *pp = &imx6_pcie->pci->pp;
 
 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
 		return 0;
 
 	imx6_pcie_pm_turnoff(imx6_pcie);
-	imx6_pcie_ltssm_disable(dev);
-	imx6_pcie_clk_disable(imx6_pcie);
-	switch (imx6_pcie->drvdata->variant) {
-	case IMX8MM:
-		if (phy_power_off(imx6_pcie->phy))
-			dev_err(dev, "unable to power off PHY\n");
-		phy_exit(imx6_pcie->phy);
-		break;
-	default:
-		break;
-	}
-
-	if (imx6_pcie->vpcie)
-		regulator_disable(imx6_pcie->vpcie);
+	imx6_pcie_stop_link(imx6_pcie->pci);
+	imx6_pcie_host_exit(pp);
 
 	return 0;
 }