From 825ce97e1faa39bfd30c3dca95fba5eb021cb534 Mon Sep 17 00:00:00 2001
From: arokux <arokux@gmail.com>
Date: Wed, 18 Sep 2013 21:45:03 +0200
Subject: [PATCH] ARM: sunxi: usb: Add Allwinner sunXi EHCI driver

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Conflicts:
	drivers/usb/host/Makefile
---
 drivers/usb/host/Kconfig      |   9 +
 drivers/usb/host/Makefile     |   1 +
 drivers/usb/host/ehci-sunxi.c | 446 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 456 insertions(+)
 create mode 100644 drivers/usb/host/ehci-sunxi.c

--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -273,6 +273,15 @@ config USB_OCTEON_EHCI
 	  USB 2.0 device support.  All CN6XXX based chips with USB are
 	  supported.
 
+config USB_SUNXI_EHCI
+	tristate "Allwinner sunXi EHCI support"
+	depends on ARCH_SUNXI
+	default n
+	help
+	  Enable support for the Allwinner sunXi on-chip EHCI
+	  controller. It is needed for high-speed (480Mbit/sec)
+	  USB 2.0 device support.
+
 endif # USB_EHCI_HCD
 
 config USB_OXU210HP_HCD
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_USB_EHCI_HCD_AT91) += ehci-
 obj-$(CONFIG_USB_EHCI_MSM)	+= ehci-msm.o
 obj-$(CONFIG_USB_EHCI_TEGRA)	+= ehci-tegra.o
 obj-$(CONFIG_USB_W90X900_EHCI)	+= ehci-w90x900.o
+obj-$(CONFIG_USB_SUNXI_EHCI)	+= ehci-sunxi.o
 
 obj-$(CONFIG_USB_OXU210HP_HCD)	+= oxu210hp-hcd.o
 obj-$(CONFIG_USB_ISP116X_HCD)	+= isp116x-hcd.o
--- /dev/null
+++ b/drivers/usb/host/ehci-sunxi.c
@@ -0,0 +1,446 @@
+/*
+ * Copyright (C) 2013 Roman Byshko
+ *
+ * Roman Byshko <rbyshko@gmail.com>
+ *
+ * Based on code from
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.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.
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+
+#include "ehci.h"
+
+#define DRV_DESC	"Allwinner sunXi EHCI driver"
+#define DRV_NAME	"sunxi-ehci"
+
+#define SUNXI_USB_PASSBY_EN	1
+
+#define SUNXI_EHCI_AHB_ICHR8_EN		BIT(10)
+#define SUNXI_EHCI_AHB_INCR4_BURST_EN	BIT(9)
+#define SUNXI_EHCI_AHB_INCRX_ALIGN_EN	BIT(8)
+#define SUNXI_EHCI_ULPI_BYPASS_EN	BIT(0)
+
+struct sunxi_ehci_hcd {
+	struct clk *phy_clk;
+	struct clk *ahb_ehci_clk;
+	struct reset_control *reset;
+	struct regulator *vbus_reg;
+	void __iomem *csr;
+	void __iomem *pmuirq;
+	int irq;
+	int id;
+};
+
+
+static void usb_phy_write(struct sunxi_ehci_hcd *sunxi_ehci,u32 addr, u32 data, u32 len)
+{
+	u32 j = 0;
+	u32 temp = 0;
+	u32 usbc_bit = 0;
+	void __iomem *dest = sunxi_ehci->csr;
+
+	usbc_bit = BIT(sunxi_ehci->id << 1);
+
+	for (j = 0; j < len; j++) {
+		temp = readl(dest);
+
+		/* clear the address portion */
+		temp &= ~(0xff << 8);
+
+		/* set the address */
+		temp |= ((addr + j) << 8);
+		writel(temp, dest);
+
+		/* set the data bit and clear usbc bit*/
+		temp = readb(dest);
+		if (data & 0x1)
+			temp |= BIT(7);
+		else
+			temp &= ~BIT(7);
+		temp &= ~usbc_bit;
+		writeb(temp, dest);
+
+		/* flip usbc_bit */
+		__set_bit(usbc_bit, dest);
+		__clear_bit(usbc_bit, dest);
+
+		data >>= 1;
+	}
+}
+
+/* FIXME: should this function be protected by a lock?
+ * ehci1 and ehci0 could call it concurrently with same csr.
+ */
+static void sunxi_usb_phy_init(struct sunxi_ehci_hcd *sunxi_ehci)
+{
+	/* The following comments are machine
+	 * translated from Chinese, you have been warned!
+	 */
+
+	/* adjust PHY's magnitude and rate */
+	usb_phy_write(sunxi_ehci, 0x20, 0x14, 5);
+
+	/* threshold adjustment disconnect */
+	usb_phy_write(sunxi_ehci, 0x2a, 3, 2);
+
+	return;
+}
+
+static void sunxi_usb_passby(struct sunxi_ehci_hcd *sunxi_ehci, int enable)
+{
+	unsigned long reg_value = 0;
+	unsigned long bits = 0;
+	static DEFINE_SPINLOCK(lock);
+	unsigned long flags = 0;
+	void __iomem *addr = sunxi_ehci->pmuirq;
+
+	bits = SUNXI_EHCI_AHB_ICHR8_EN |
+		SUNXI_EHCI_AHB_INCR4_BURST_EN |
+		SUNXI_EHCI_AHB_INCRX_ALIGN_EN |
+		SUNXI_EHCI_ULPI_BYPASS_EN;
+
+	spin_lock_irqsave(&lock, flags);
+
+	reg_value = readl(addr);
+
+	if (enable)
+		reg_value |= bits;
+	else
+		reg_value &= ~bits;
+
+	writel(reg_value, addr);
+
+	spin_unlock_irqrestore(&lock, flags);
+
+	return;
+}
+
+static void sunxi_ehci_disable(struct sunxi_ehci_hcd *sunxi_ehci)
+{
+	regulator_disable(sunxi_ehci->vbus_reg);
+
+	sunxi_usb_passby(sunxi_ehci, !SUNXI_USB_PASSBY_EN);
+
+	clk_disable_unprepare(sunxi_ehci->ahb_ehci_clk);
+	clk_disable_unprepare(sunxi_ehci->phy_clk);
+
+	reset_control_assert(sunxi_ehci->reset);
+}
+
+static int sunxi_ehci_enable(struct sunxi_ehci_hcd *sunxi_ehci)
+{
+	int ret;
+
+	ret = clk_prepare_enable(sunxi_ehci->phy_clk);
+	if (ret)
+		return ret;
+
+	ret = reset_control_deassert(sunxi_ehci->reset);
+	if (ret)
+		goto fail1;
+
+	ret = clk_prepare_enable(sunxi_ehci->ahb_ehci_clk);
+	if (ret)
+		goto fail2;
+
+	sunxi_usb_phy_init(sunxi_ehci);
+
+	sunxi_usb_passby(sunxi_ehci, SUNXI_USB_PASSBY_EN);
+
+	ret = regulator_enable(sunxi_ehci->vbus_reg);
+	if (ret)
+		goto fail3;
+
+	return 0;
+
+fail3:
+	clk_disable_unprepare(sunxi_ehci->ahb_ehci_clk);
+fail2:
+	reset_control_assert(sunxi_ehci->reset);
+fail1:
+	clk_disable_unprepare(sunxi_ehci->phy_clk);
+
+	return ret;
+}
+
+#ifdef CONFIG_PM
+static int sunxi_ehci_suspend(struct device *dev)
+{
+	struct sunxi_ehci_hcd *sunxi_ehci = NULL;
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	int ret;
+
+	bool do_wakeup = device_may_wakeup(dev);
+
+	ret = ehci_suspend(hcd, do_wakeup);
+
+	sunxi_ehci = (struct sunxi_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+	sunxi_ehci_disable(sunxi_ehci);
+
+	return ret;
+}
+
+static int sunxi_ehci_resume(struct device *dev)
+{
+	struct sunxi_ehci_hcd *sunxi_ehci = NULL;
+	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	int ret;
+
+	sunxi_ehci = (struct sunxi_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+	ret = sunxi_ehci_enable(sunxi_ehci);
+	if (ret)
+		return ret;
+
+	return ehci_resume(hcd, false);
+}
+
+
+static const struct dev_pm_ops sunxi_ehci_pmops = {
+	.suspend	= sunxi_ehci_suspend,
+	.resume		= sunxi_ehci_resume,
+};
+
+#define SUNXI_EHCI_PMOPS (&sunxi_ehci_pmops)
+#else /* !CONFIG_PM */
+#define SUNXI_EHCI_PMOPS NULL
+#endif /* CONFIG_PM */
+
+static const struct ehci_driver_overrides sunxi_overrides __initconst = {
+	.reset =	NULL,
+	.extra_priv_size	= sizeof(struct sunxi_ehci_hcd),
+};
+
+/* FIXME: Should there be two instances of hc_driver,
+ * or one is enough to handle two EHCI controllers? */
+static struct hc_driver __read_mostly sunxi_ehci_hc_driver;
+
+static int sunxi_ehci_init(struct platform_device *pdev, struct usb_hcd *hcd,
+			   struct sunxi_ehci_hcd *sunxi_ehci)
+{
+	void __iomem *ehci_regs = NULL;
+	struct resource *res = NULL;
+
+	sunxi_ehci->vbus_reg = devm_regulator_get(&pdev->dev, "vbus");
+	if (IS_ERR(sunxi_ehci->vbus_reg)) {
+		if (PTR_ERR(sunxi_ehci->vbus_reg) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+
+		dev_info(&pdev->dev, "no USB VBUS power supply found\n");
+	}
+
+	sunxi_ehci->id = of_alias_get_id(pdev->dev.of_node, "ehci");
+	if (sunxi_ehci->id < 0)
+		return sunxi_ehci->id;
+
+	/* FIXME: should res be freed on some failure? */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+	ehci_regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(ehci_regs))
+		return PTR_ERR(ehci_regs);
+
+	hcd->rsrc_start = res->start;
+	hcd->rsrc_len = resource_size(res);
+	hcd->regs = ehci_regs;
+	hcd_to_ehci(hcd)->caps = ehci_regs;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+	sunxi_ehci->pmuirq = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(sunxi_ehci->pmuirq))
+		return PTR_ERR(sunxi_ehci->pmuirq);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+
+	/* FIXME: this one byte needs to be shared between both EHCIs,
+	 * that is why ioremap instead of devm_ioremap_resource,
+	 * memory is not unmaped back for now.
+	 */
+	sunxi_ehci->csr = ioremap(res->start, resource_size(res));
+	if (IS_ERR(sunxi_ehci->csr)) {
+		dev_err(&pdev->dev, "failed to remap memory\n");
+		return PTR_ERR(sunxi_ehci->csr);
+	}
+
+	sunxi_ehci->irq = platform_get_irq(pdev, 0);
+	if (!sunxi_ehci->irq) {
+		dev_err(&pdev->dev, "failed to get IRQ\n");
+		return -ENODEV;
+	}
+
+	sunxi_ehci->phy_clk = devm_clk_get(&pdev->dev, "usb_phy");
+	if (IS_ERR(sunxi_ehci->phy_clk)) {
+		dev_err(&pdev->dev, "failed to get usb_phy clock\n");
+		return PTR_ERR(sunxi_ehci->phy_clk);
+	}
+	sunxi_ehci->ahb_ehci_clk = devm_clk_get(&pdev->dev, "ahb_ehci");
+	if (IS_ERR(sunxi_ehci->ahb_ehci_clk)) {
+		dev_err(&pdev->dev, "failed to get ahb_ehci clock\n");
+		return PTR_ERR(sunxi_ehci->ahb_ehci_clk);
+	}
+
+	sunxi_ehci->reset = reset_control_get(&pdev->dev, "ehci_reset");
+	if (IS_ERR(sunxi_ehci->reset))
+	{
+		dev_err(&pdev->dev, "failed to get ehci_reset reset line\n");
+		return PTR_ERR(sunxi_ehci->reset);
+	}
+
+	return 0;
+}
+
+static int sunxi_ehci_probe(struct platform_device *pdev)
+{
+	struct sunxi_ehci_hcd *sunxi_ehci = NULL;
+	struct usb_hcd *hcd = NULL;
+	int ret;
+
+	if (pdev->num_resources != 4) {
+		dev_err(&pdev->dev, "invalid number of resources: %i\n",
+		       pdev->num_resources);
+		return -ENODEV;
+	}
+
+	if (pdev->resource[0].flags != IORESOURCE_MEM
+			|| pdev->resource[1].flags != IORESOURCE_MEM
+			|| pdev->resource[2].flags != IORESOURCE_MEM
+			|| pdev->resource[3].flags != IORESOURCE_IRQ) {
+		dev_err(&pdev->dev, "invalid resource type\n");
+		return -ENODEV;
+	}
+
+	if (!pdev->dev.dma_mask)
+		pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
+	if (!pdev->dev.coherent_dma_mask)
+		pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+
+	hcd = usb_create_hcd(&sunxi_ehci_hc_driver, &pdev->dev,
+			     dev_name(&pdev->dev));
+	if (!hcd) {
+		dev_err(&pdev->dev, "unable to create HCD\n");
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, hcd);
+
+	sunxi_ehci = (struct sunxi_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+	ret = sunxi_ehci_init(pdev, hcd, sunxi_ehci);
+	if (ret)
+		goto fail1;
+
+	ret = sunxi_ehci_enable(sunxi_ehci);
+	if (ret)
+		goto fail1;
+
+	ret = usb_add_hcd(hcd, sunxi_ehci->irq, IRQF_SHARED | IRQF_DISABLED);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to add USB HCD\n");
+		goto fail2;
+	}
+
+	return 0;
+
+fail2:
+	sunxi_ehci_disable(sunxi_ehci);
+
+fail1:
+	usb_put_hcd(hcd);
+	return ret;
+}
+
+static int sunxi_ehci_remove(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(pdev);
+	struct sunxi_ehci_hcd *sunxi_ehci = NULL;
+
+	sunxi_ehci = (struct sunxi_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+	usb_remove_hcd(hcd);
+
+	sunxi_ehci_disable(sunxi_ehci);
+
+	usb_put_hcd(hcd);
+
+	return 0;
+}
+
+static void sunxi_ehci_shutdown(struct platform_device *pdev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(pdev);
+	struct sunxi_ehci_hcd *sunxi_ehci = NULL;
+
+	sunxi_ehci = (struct sunxi_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+	usb_hcd_platform_shutdown(pdev);
+
+	sunxi_ehci_disable(sunxi_ehci);
+}
+
+static const struct of_device_id ehci_of_match[] = {
+	{.compatible = "allwinner,sunxi-ehci"},
+	{},
+};
+
+static struct platform_driver ehci_sunxi_driver = {
+	.driver = {
+		.of_match_table = ehci_of_match,
+		.name = DRV_NAME,
+		.pm = SUNXI_EHCI_PMOPS,
+	},
+	.probe = sunxi_ehci_probe,
+	.remove = sunxi_ehci_remove,
+	.shutdown = sunxi_ehci_shutdown,
+};
+
+static int __init sunxi_ehci_init_module(void)
+{
+	if (usb_disabled())
+		return -ENODEV;
+
+	pr_info(DRV_NAME ": " DRV_DESC "\n");
+
+	ehci_init_driver(&sunxi_ehci_hc_driver, &sunxi_overrides);
+
+	return platform_driver_register(&ehci_sunxi_driver);
+}
+module_init(sunxi_ehci_init_module);
+
+static void __exit sunxi_ehci_exit_module(void)
+{
+	platform_driver_unregister(&ehci_sunxi_driver);
+}
+module_exit(sunxi_ehci_exit_module);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DEVICE_TABLE(of, ehci_of_match);
+MODULE_AUTHOR("Roman Byshko <rbyshko@gmail.com>");