patches/0894-usb-add-a-flag-to-skip-PHY-initialization-to-struct-.patch

From 5caf43318aa2f14f82d496ca2debff200fead56a Mon Sep 17 00:00:00 2001
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date: Sat, 3 Mar 2018 22:43:03 +0100
Subject: [PATCH 0894/1795] usb: add a flag to skip PHY initialization to
 struct usb_hcd

The USB HCD core driver parses the device-tree node for "phys" and
"usb-phys" properties. It also manages the power state of these PHYs
automatically.
However, drivers may opt-out of this behavior by setting "phy" or
"usb_phy" in struct usb_hcd to a non-null value. An example where this
is required is the "Qualcomm USB2 controller", implemented by the
chipidea driver. The hardware requires that the PHY is only powered on
after the "reset completed" event from the controller is received.

A follow-up patch will allow the USB HCD core driver to manage more than
one PHY. Add a new "skip_phy_initialization" bitflag to struct usb_hcd
so drivers can opt-out of any PHY management provided by the USB HCD
core driver.

This also updates the existing drivers so they use the new flag if they
want to opt out of the PHY management provided by the USB HCD core
driver. This means that for these drivers the new "multiple PHY"
handling (which will be added in a follow-up patch) will be disabled as
well.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.con>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 4e88d4c083016454f179686529ae65d70b933b58)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/usb/chipidea/host.c      | 6 ++----
 drivers/usb/core/hcd.c           | 4 ++--
 drivers/usb/host/ehci-fsl.c      | 2 ++
 drivers/usb/host/ehci-platform.c | 4 ++--
 drivers/usb/host/ehci-tegra.c    | 1 +
 drivers/usb/host/ohci-omap.c     | 1 +
 drivers/usb/host/ohci-platform.c | 4 ++--
 drivers/usb/host/xhci-plat.c     | 1 +
 include/linux/usb/hcd.h          | 6 ++++++
 9 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index a49e8567ac7d..9e26951f696c 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -137,10 +137,8 @@ static int host_start(struct ci_hdrc *ci)
 
 	hcd->power_budget = ci->platdata->power_budget;
 	hcd->tpl_support = ci->platdata->tpl_support;
-	if (ci->phy)
-		hcd->phy = ci->phy;
-	else
-		hcd->usb_phy = ci->usb_phy;
+	if (ci->phy || ci->usb_phy)
+		hcd->skip_phy_initialization = 1;
 
 	ehci = hcd_to_ehci(hcd);
 	ehci->caps = ci->hw_bank.cap;
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 9fa30a6ada6e..d92c366d58b3 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2742,7 +2742,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
 	int retval;
 	struct usb_device *rhdev;
 
-	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) {
+	if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->skip_phy_initialization) {
 		struct usb_phy *phy = usb_get_phy_dev(hcd->self.sysdev, 0);
 
 		if (IS_ERR(phy)) {
@@ -2760,7 +2760,7 @@ int usb_add_hcd(struct usb_hcd *hcd,
 		}
 	}
 
-	if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) {
+	if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->skip_phy_initialization) {
 		struct phy *phy = phy_get(hcd->self.sysdev, "usb");
 
 		if (IS_ERR(phy)) {
diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 7c4bb32230d2..0831917321fe 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -169,6 +169,8 @@ static int fsl_ehci_drv_probe(struct platform_device *pdev)
 			retval = -ENODEV;
 			goto err2;
 		}
+
+		hcd->skip_phy_initialization = 1;
 	}
 #endif
 	return retval;
diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c
index cb77af3a71c1..86d535fe5b44 100644
--- a/drivers/usb/host/ehci-platform.c
+++ b/drivers/usb/host/ehci-platform.c
@@ -222,9 +222,9 @@ static int ehci_platform_probe(struct platform_device *dev)
 			if (IS_ERR(priv->phys[phy_num])) {
 				err = PTR_ERR(priv->phys[phy_num]);
 					goto err_put_hcd;
-			} else if (!hcd->phy) {
+			} else {
 				/* Avoiding phy_get() in usb_add_hcd() */
-				hcd->phy = priv->phys[phy_num];
+				hcd->skip_phy_initialization = 1;
 			}
 		}
 
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index fe8423e17877..ae5439f96530 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -472,6 +472,7 @@ static int tegra_ehci_probe(struct platform_device *pdev)
 		goto cleanup_clk_en;
 	}
 	hcd->usb_phy = u_phy;
+	hcd->skip_phy_initialization = 1;
 
 	tegra->needs_double_reset = of_property_read_bool(pdev->dev.of_node,
 		"nvidia,needs-double-reset");
diff --git a/drivers/usb/host/ohci-omap.c b/drivers/usb/host/ohci-omap.c
index 0201c49bc4fc..d8d35d456456 100644
--- a/drivers/usb/host/ohci-omap.c
+++ b/drivers/usb/host/ohci-omap.c
@@ -230,6 +230,7 @@ static int ohci_omap_reset(struct usb_hcd *hcd)
 		} else {
 			return -EPROBE_DEFER;
 		}
+		hcd->skip_phy_initialization = 1;
 		ohci->start_hnp = start_hnp;
 	}
 #endif
diff --git a/drivers/usb/host/ohci-platform.c b/drivers/usb/host/ohci-platform.c
index 908ebcfbc350..488b811b565f 100644
--- a/drivers/usb/host/ohci-platform.c
+++ b/drivers/usb/host/ohci-platform.c
@@ -189,9 +189,9 @@ static int ohci_platform_probe(struct platform_device *dev)
 			if (IS_ERR(priv->phys[phy_num])) {
 				err = PTR_ERR(priv->phys[phy_num]);
 				goto err_put_hcd;
-			} else if (!hcd->phy) {
+			} else {
 				/* Avoiding phy_get() in usb_add_hcd() */
-				hcd->phy = priv->phys[phy_num];
+				hcd->skip_phy_initialization = 1;
 			}
 		}
 
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index c435df29cdb8..ea089fdda611 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -284,6 +284,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
 		ret = usb_phy_init(hcd->usb_phy);
 		if (ret)
 			goto put_usb3_hcd;
+		hcd->skip_phy_initialization = 1;
 	}
 
 	ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 176900528822..693502c84c04 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -151,6 +151,12 @@ struct usb_hcd {
 	unsigned		msix_enabled:1;	/* driver has MSI-X enabled? */
 	unsigned		msi_enabled:1;	/* driver has MSI enabled? */
 	unsigned		remove_phy:1;	/* auto-remove USB phy */
+	/*
+	 * do not manage the PHY state in the HCD core, instead let the driver
+	 * handle this (for example if the PHY can only be turned on after a
+	 * specific event)
+	 */
+	unsigned		skip_phy_initialization:1;
 
 	/* The next flag is a stopgap, to be removed when all the HCDs
 	 * support the new root-hub polling mechanism. */
-- 
2.19.0