[PATCH v2 14/18] ARM: mvebu: Add support for USB cluster on the Armada 375 SoC

[Gregory CLEMENT]

The Armada 375 SoC comes with an USB2 host and device controller and
an USB3 controller. The USB cluster control register allows to manage
common features of both USB controllers.

Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
---
 arch/arm/mach-mvebu/Makefile      |  2 +-
 arch/arm/mach-mvebu/usb-cluster.c | 96 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 97 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/mach-mvebu/usb-cluster.c

diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile
index a63e43b6b451..dec05e7e1802 100644
--- a/arch/arm/mach-mvebu/Makefile
+++ b/arch/arm/mach-mvebu/Makefile
@@ -4,7 +4,7 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/$(src)/include \
 AFLAGS_coherency_ll.o		:= -Wa,-march=armv7-a
 
 obj-y				 += system-controller.o mvebu-soc-id.o
-obj-$(CONFIG_MACH_MVEBU_V7)      += board-v7.o
+obj-$(CONFIG_MACH_MVEBU_V7)      += board-v7.o usb-cluster.o
 obj-$(CONFIG_MACH_DOVE)		 += dove.o
 obj-$(CONFIG_ARCH_MVEBU)	 += coherency.o coherency_ll.o pmsu.o
 obj-$(CONFIG_SMP)                += platsmp.o headsmp.o
diff --git a/arch/arm/mach-mvebu/usb-cluster.c b/arch/arm/mach-mvebu/usb-cluster.c
new file mode 100644
index 000000000000..4c15d282db23
--- /dev/null
+++ b/arch/arm/mach-mvebu/usb-cluster.c
@@ -0,0 +1,96 @@
+/*
+ * USB cluster support for Armada 375 platform.
+ *
+ * Copyright (C) 2014 Marvell
+ *
+ * Gregory CLEMENT <gregory.clement at free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * Armada 375 comes with an USB2 host and device controller and an
+ * USB3 controller. The USB cluster control register allows to manage
+ * common features of both USB controller.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#define USB2_PHY_CONFIG_ENABLE BIT(0) /* active low */
+
+static struct of_device_id of_usb_cluster_table[] = {
+	{ .compatible = "marvell,armada-375-usb-cluster", },
+	{ /* end of list */ },
+};
+
+static int __init mvebu_usb_cluster_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_matching_node(NULL, of_usb_cluster_table);
+	if (np) {
+		void __iomem *usb_cluster_base;
+		u32 reg;
+		struct device_node *ehci_node, *xhci_node;
+		struct property *ehci_status;
+		bool use_usb3 = false;
+
+		usb_cluster_base = of_iomap(np, 0);
+		BUG_ON(!usb_cluster_base);
+
+		xhci_node = of_find_compatible_node(NULL, NULL,
+						"marvell,armada-375-xhci");
+
+		if (xhci_node && of_device_is_available(xhci_node))
+			use_usb3 = true;
+
+		ehci_node = of_find_compatible_node(NULL, NULL,
+						"marvell,orion-ehci");
+
+		if (ehci_node && of_device_is_available(ehci_node)
+			&& use_usb3) {
+			/*
+			 * We can't use usb2 and usb3 in the same time, so let's
+			 * disbale usb2 and complain about it to the user askinf
+			 * to fix the device tree.
+			 */
+
+			ehci_status = kzalloc(sizeof(struct property),
+					GFP_KERNEL);
+			WARN_ON(!ehci_status);
+
+			ehci_status->value = kstrdup("disabled", GFP_KERNEL);
+			WARN_ON(!ehci_status->value);
+
+			ehci_status->length = 8;
+			ehci_status->name = kstrdup("status", GFP_KERNEL);
+			WARN_ON(!ehci_status->name);
+
+			of_update_property(ehci_node, ehci_status);
+			pr_err("%s: armada-375-xhci and orion-ehci are incompatible for this SoC.\n",
+				__func__);
+			pr_err("Please fix your dts!\n");
+			pr_err("orion-ehci have been disabled by default...\n");
+
+		}
+
+		reg = readl(usb_cluster_base);
+		if (use_usb3)
+			reg |= USB2_PHY_CONFIG_ENABLE;
+		else
+			reg &= ~USB2_PHY_CONFIG_ENABLE;
+		writel(reg, usb_cluster_base);
+
+		of_node_put(ehci_node);
+		of_node_put(xhci_node);
+		of_node_put(np);
+		iounmap(usb_cluster_base);
+	}
+
+	return 0;
+}
+postcore_initcall(mvebu_usb_cluster_init);
-- 
1.8.1.2