openwrtv3/target/linux/sunxi/patches-4.4/144-usb-ehci-plat-support-multiple-reset-ctrllines.patch

From 957e8f96c67052ca843ea9ffc5223662b973e5de Mon Sep 17 00:00:00 2001
From: Reinder de Haan <patchesrdh@mveas.com>
Date: Sun, 15 Nov 2015 14:24:46 +0100
Subject: [PATCH] ehci-platform: Add support for controllers with multiple
 reset lines

At least the EHCI/OHCI found on the Allwinnner H3 SoC needs multiple
reset lines, the controller will not initialize while the reset for
its companion is still asserted, which means we need to de-assert
2 resets for the controller to work.

Signed-off-by: Reinder de Haan <patchesrdh@mveas.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v2:
-Use the new reset_control_[de]assert_shared reset-controller functions
---
 Documentation/devicetree/bindings/usb/usb-ehci.txt |  2 +-
 drivers/usb/host/ehci-platform.c                   | 47 +++++++++++++---------
 2 files changed, 30 insertions(+), 19 deletions(-)

--- a/Documentation/devicetree/bindings/usb/usb-ehci.txt
+++ b/Documentation/devicetree/bindings/usb/usb-ehci.txt
@@ -18,7 +18,7 @@ Optional properties:
  - clocks : a list of phandle + clock specifier pairs
  - phys : phandle + phy specifier pair
  - phy-names : "usb"
- - resets : phandle + reset specifier pair
+ - resets : a list of phandle + reset specifier pairs
 
 Example (Sequoia 440EPx):
     ehci@e0000300 {
--- a/drivers/usb/host/ehci-platform.c
+++ b/drivers/usb/host/ehci-platform.c
@@ -39,11 +39,12 @@
 
 #define DRIVER_DESC "EHCI generic platform driver"
 #define EHCI_MAX_CLKS 3
+#define EHCI_MAX_RESETS 2
 #define hcd_to_ehci_priv(h) ((struct ehci_platform_priv *)hcd_to_ehci(h)->priv)
 
 struct ehci_platform_priv {
 	struct clk *clks[EHCI_MAX_CLKS];
-	struct reset_control *rst;
+	struct reset_control *resets[EHCI_MAX_RESETS];
 	struct phy **phys;
 	int num_phys;
 	bool reset_on_resume;
@@ -149,7 +150,7 @@ static int ehci_platform_probe(struct pl
 	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
 	struct ehci_platform_priv *priv;
 	struct ehci_hcd *ehci;
-	int err, irq, phy_num, clk = 0;
+	int err, irq, phy_num, clk = 0, rst = 0;
 
 	if (usb_disabled())
 		return -ENODEV;
@@ -232,18 +233,24 @@ static int ehci_platform_probe(struct pl
 				break;
 			}
 		}
-	}
 
-	priv->rst = devm_reset_control_get_optional(&dev->dev, NULL);
-	if (IS_ERR(priv->rst)) {
-		err = PTR_ERR(priv->rst);
-		if (err == -EPROBE_DEFER)
-			goto err_put_clks;
-		priv->rst = NULL;
-	} else {
-		err = reset_control_deassert(priv->rst);
-		if (err)
-			goto err_put_clks;
+		for (rst = 0; rst < EHCI_MAX_RESETS; rst++) {
+			priv->resets[rst] =
+				of_reset_control_get_by_index(dev->dev.of_node,
+							      rst);
+			if (IS_ERR(priv->resets[rst])) {
+				err = PTR_ERR(priv->resets[rst]);
+				if (err == -EPROBE_DEFER)
+					goto err_reset;
+				priv->resets[rst] = NULL;
+				break;
+			}
+			err = reset_control_deassert_shared(priv->resets[rst]);
+			if (err) {
+				reset_control_put(priv->resets[rst]);
+				goto err_reset;
+			}
+		}
 	}
 
 	if (pdata->big_endian_desc)
@@ -302,8 +309,10 @@ err_power:
 	if (pdata->power_off)
 		pdata->power_off(dev);
 err_reset:
-	if (priv->rst)
-		reset_control_assert(priv->rst);
+	while (--rst >= 0) {
+		reset_control_assert_shared(priv->resets[rst]);
+		reset_control_put(priv->resets[rst]);
+	}
 err_put_clks:
 	while (--clk >= 0)
 		clk_put(priv->clks[clk]);
@@ -321,15 +330,17 @@ static int ehci_platform_remove(struct p
 	struct usb_hcd *hcd = platform_get_drvdata(dev);
 	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
 	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
-	int clk;
+	int clk, rst;
 
 	usb_remove_hcd(hcd);
 
 	if (pdata->power_off)
 		pdata->power_off(dev);
 
-	if (priv->rst)
-		reset_control_assert(priv->rst);
+	for (rst = 0; rst < EHCI_MAX_RESETS && priv->resets[rst]; rst++) {
+		reset_control_assert_shared(priv->resets[rst]);
+		reset_control_put(priv->resets[rst]);
+	}
 
 	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++)
 		clk_put(priv->clks[clk]);