[PATCH v1 2/6] usb: chipidea: tegra: Avoid controller/PHY init if bus is externally controlled

[Svyatoslav Ryhel]

If the USB controller and PHY are externally controlled, then the
registration of the controller and the PHY initialization should be
skipped, since these configurations must be done by the device that
controls the bus to work correctly.

Signed-off-by: Svyatoslav Ryhel <clamor95 at gmail.com>
---
 drivers/usb/chipidea/ci_hdrc_tegra.c | 36 +++++++++++++++++-----------
 1 file changed, 22 insertions(+), 14 deletions(-)

diff --git a/drivers/usb/chipidea/ci_hdrc_tegra.c b/drivers/usb/chipidea/ci_hdrc_tegra.c
index 372788f0f970..593390a818d1 100644
--- a/drivers/usb/chipidea/ci_hdrc_tegra.c
+++ b/drivers/usb/chipidea/ci_hdrc_tegra.c
@@ -32,6 +32,7 @@ struct tegra_usb {
 	struct clk *clk;
 
 	bool needs_double_reset;
+	bool externally_controlled;
 };
 
 struct tegra_usb_soc_info {
@@ -312,20 +313,25 @@ static int tegra_usb_probe(struct platform_device *pdev)
 	if (device_property_present(&pdev->dev, "nvidia,needs-double-reset"))
 		usb->needs_double_reset = true;
 
+	if (device_property_present(&pdev->dev, "nvidia,external-control"))
+		usb->externally_controlled = true;
+
 	err = tegra_usb_reset_controller(&pdev->dev);
 	if (err) {
 		dev_err_probe(&pdev->dev, err, "failed to reset controller");
 		goto fail_power_off;
 	}
 
-	/*
-	 * USB controller registers shouldn't be touched before PHY is
-	 * initialized, otherwise CPU will hang because clocks are gated.
-	 * PHY driver controls gating of internal USB clocks on Tegra.
-	 */
-	err = usb_phy_init(usb->phy);
-	if (err)
-		goto fail_power_off;
+	if (!usb->externally_controlled) {
+		/*
+		 * USB controller registers shouldn't be touched before PHY is
+		 * initialized, otherwise CPU will hang because clocks are gated.
+		 * PHY driver controls gating of internal USB clocks on Tegra.
+		 */
+		err = usb_phy_init(usb->phy);
+		if (err)
+			goto fail_power_off;
+	}
 
 	/* setup and register ChipIdea HDRC device */
 	usb->soc = soc;
@@ -342,12 +348,14 @@ static int tegra_usb_probe(struct platform_device *pdev)
 	if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_ULPI)
 		usb->data.flags &= ~CI_HDRC_SUPPORTS_RUNTIME_PM;
 
-	usb->dev = ci_hdrc_add_device(&pdev->dev, pdev->resource,
-				      pdev->num_resources, &usb->data);
-	if (IS_ERR(usb->dev)) {
-		err = dev_err_probe(&pdev->dev, PTR_ERR(usb->dev),
-				    "failed to add HDRC device");
-		goto phy_shutdown;
+	if (!usb->externally_controlled) {
+		usb->dev = ci_hdrc_add_device(&pdev->dev, pdev->resource,
+					      pdev->num_resources, &usb->data);
+		if (IS_ERR(usb->dev)) {
+			err = dev_err_probe(&pdev->dev, PTR_ERR(usb->dev),
+					    "failed to add HDRC device");
+			goto phy_shutdown;
+		}
 	}
 
 	return 0;
-- 
2.51.0