usb: add support for generic EHCI devices

This driver is meant to be used with any EHCI-compatible host
controller in case if there's no need for platform-specific
glue such as setup of controller or PHY's power mode via
GPIOs etc.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>

drivers/usb/host/Kconfig

@@ -73,4 +73,12 @@ config USB_EHCI_UNIPHIER
 	---help---
 	  Enables support for the on-chip EHCI controller on UniPhier SoCs.
 
+config USB_EHCI_GENERIC
+	bool "Support for generic EHCI USB controller"
+	depends on OF_CONTROL
+	depends on DM_USB
+	default n
+	---help---
+	  Enables support for generic EHCI controller.
+
 endif

drivers/usb/host/Makefile

@@ -32,6 +32,7 @@ else
 obj-$(CONFIG_USB_EHCI_FSL) += ehci-fsl.o
 endif
 obj-$(CONFIG_USB_EHCI_FARADAY) += ehci-faraday.o
+obj-$(CONFIG_USB_EHCI_GENERIC) += ehci-generic.o
 obj-$(CONFIG_USB_EHCI_EXYNOS) += ehci-exynos.o
 obj-$(CONFIG_USB_EHCI_MXC) += ehci-mxc.o
 obj-$(CONFIG_USB_EHCI_MXS) += ehci-mxs.o

drivers/usb/host/ehci-generic.c

@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2015 Alexey Brodkin <abrodkin@synopsys.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include "ehci.h"
+
+/*
+ * Even though here we don't explicitly use "struct ehci_ctrl"
+ * ehci_register() expects it to be the first thing that resides in
+ * device's private data.
+ */
+struct generic_ehci {
+	struct ehci_ctrl ctrl;
+};
+
+static int ehci_usb_probe(struct udevice *dev)
+{
+	struct ehci_hccr *hccr = (struct ehci_hccr *)dev_get_addr(dev);
+	struct ehci_hcor *hcor;
+
+	hcor = (struct ehci_hcor *)((uintptr_t)hccr +
+				    HC_LENGTH(ehci_readl(&hccr->cr_capbase)));
+
+	return ehci_register(dev, hccr, hcor, NULL, 0, USB_INIT_HOST);
+}
+
+static int ehci_usb_remove(struct udevice *dev)
+{
+	return ehci_deregister(dev);
+}
+
+static const struct udevice_id ehci_usb_ids[] = {
+	{ .compatible = "generic-ehci" },
+	{ }
+};
+
+U_BOOT_DRIVER(ehci_generic) = {
+	.name	= "ehci_generic",
+	.id	= UCLASS_USB,
+	.of_match = ehci_usb_ids,
+	.probe = ehci_usb_probe,
+	.remove = ehci_usb_remove,
+	.ops	= &ehci_usb_ops,
+	.priv_auto_alloc_size = sizeof(struct generic_ehci),
+	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
+};