--- /dev/null
+/*
+ * drivers/usb/otg/tegra-otg.c
+ *
+ * OTG transceiver driver for Tegra UTMI phy
+ *
+ * Copyright (C) 2010 NVIDIA Corp.
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/gadget.h>
+#include <linux/usb/hcd.h>
+#include <linux/platform_device.h>
+#include <linux/tegra_usb.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+
+#define USB_PHY_WAKEUP 0x408
+#define USB_ID_INT_EN (1 << 0)
+#define USB_ID_INT_STATUS (1 << 1)
+#define USB_ID_STATUS (1 << 2)
+#define USB_ID_PIN_WAKEUP_EN (1 << 6)
+#define USB_VBUS_WAKEUP_EN (1 << 30)
+#define USB_VBUS_INT_EN (1 << 8)
+#define USB_VBUS_INT_STATUS (1 << 9)
+#define USB_VBUS_STATUS (1 << 10)
+#define USB_INTS (USB_VBUS_INT_STATUS | USB_ID_INT_STATUS)
+
+struct tegra_otg_data {
+ struct otg_transceiver otg;
+ unsigned long int_status;
+ spinlock_t lock;
+ void __iomem *regs;
+ struct clk *clk;
+ int irq;
+ struct platform_device *host;
+ struct platform_device *pdev;
+};
+
+static inline unsigned long otg_readl(struct tegra_otg_data *tegra,
+ unsigned int offset)
+{
+ return readl(tegra->regs + offset);
+}
+
+static inline void otg_writel(struct tegra_otg_data *tegra, unsigned long val,
+ unsigned int offset)
+{
+ writel(val, tegra->regs + offset);
+}
+
+static const char *tegra_state_name(enum usb_otg_state state)
+{
+ if (state == OTG_STATE_A_HOST)
+ return "HOST";
+ if (state == OTG_STATE_B_PERIPHERAL)
+ return "PERIPHERAL";
+ if (state == OTG_STATE_A_SUSPEND)
+ return "SUSPEND";
+ return "INVALID";
+}
+
+void tegra_start_host(struct tegra_otg_data *tegra)
+{
+ int retval;
+ struct platform_device *pdev;
+ struct platform_device *host = tegra->host;
+ void *platform_data;
+
+ pdev = platform_device_alloc(host->name, host->id);
+ if (!pdev)
+ return;
+
+ if (host->resource) {
+ retval = platform_device_add_resources(pdev, host->resource,
+ host->num_resources);
+ if (retval)
+ goto error;
+ }
+
+ pdev->dev.dma_mask = host->dev.dma_mask;
+ pdev->dev.coherent_dma_mask = host->dev.coherent_dma_mask;
+
+ platform_data = kmalloc(sizeof(struct tegra_ehci_platform_data), GFP_KERNEL);
+ if (!platform_data)
+ goto error;
+
+ memcpy(platform_data, host->dev.platform_data,
+ sizeof(struct tegra_ehci_platform_data));
+ pdev->dev.platform_data = platform_data;
+
+ retval = platform_device_add(pdev);
+ if (retval)
+ goto error_add;
+
+ tegra->pdev = pdev;
+ return;
+
+error_add:
+ kfree(platform_data);
+error:
+ pr_err("%s: failed to add the host contoller device\n", __func__);
+ platform_device_put(pdev);
+}
+
+void tegra_stop_host(struct tegra_otg_data *tegra)
+{
+ if (tegra->pdev) {
+ platform_device_unregister(tegra->pdev);
+ tegra->pdev = NULL;
+ }
+}
+
+static irqreturn_t tegra_otg_irq_thread(int irq, void *data)
+{
+ struct tegra_otg_data *tegra = data;
+ struct otg_transceiver *otg = &tegra->otg;
+ enum usb_otg_state from = otg->state;
+ enum usb_otg_state to = OTG_STATE_UNDEFINED;
+ unsigned long flags;
+ unsigned long status;
+
+ clk_enable(tegra->clk);
+
+ status = otg_readl(tegra, USB_PHY_WAKEUP);
+
+ spin_lock_irqsave(&tegra->lock, flags);
+
+ if (tegra->int_status & USB_ID_INT_STATUS) {
+ if (status & USB_ID_STATUS)
+ to = OTG_STATE_A_SUSPEND;
+ else
+ to = OTG_STATE_A_HOST;
+ } else if (tegra->int_status & USB_VBUS_INT_STATUS) {
+ if (status & USB_VBUS_STATUS)
+ to = OTG_STATE_B_PERIPHERAL;
+ else
+ to = OTG_STATE_A_SUSPEND;
+ }
+
+ tegra->int_status = 0;
+
+ spin_unlock_irqrestore(&tegra->lock, flags);
+
+ otg->state = to;
+
+ dev_info(tegra->otg.dev, "%s --> %s", tegra_state_name(from),
+ tegra_state_name(to));
+
+ if (to == OTG_STATE_A_SUSPEND) {
+ if (from == OTG_STATE_A_HOST && tegra->host)
+ tegra_stop_host(tegra);
+ else if (from == OTG_STATE_B_PERIPHERAL && otg->gadget)
+ usb_gadget_vbus_disconnect(otg->gadget);
+ } else if (to == OTG_STATE_B_PERIPHERAL && otg->gadget) {
+ if (from == OTG_STATE_A_SUSPEND)
+ usb_gadget_vbus_connect(otg->gadget);
+ } else if (to == OTG_STATE_A_HOST && tegra->host) {
+ if (from == OTG_STATE_A_SUSPEND)
+ tegra_start_host(tegra);
+ }
+
+ clk_disable(tegra->clk);
+
+ return IRQ_HANDLED;
+
+}
+
+static irqreturn_t tegra_otg_irq(int irq, void *data)
+{
+ struct tegra_otg_data *tegra = data;
+ unsigned long val;
+
+ clk_enable(tegra->clk);
+
+ spin_lock(&tegra->lock);
+ val = otg_readl(tegra, USB_PHY_WAKEUP);
+ otg_writel(tegra, val, USB_PHY_WAKEUP);
+
+ /* and the interrupt enables into the interrupt status bits */
+ val = (val & (val << 1)) & USB_INTS;
+
+ tegra->int_status |= val;
+
+ spin_unlock(&tegra->lock);
+
+ clk_disable(tegra->clk);
+
+ return (val) ? IRQ_WAKE_THREAD : IRQ_NONE;
+}
+
+static int tegra_otg_set_peripheral(struct otg_transceiver *otg,
+ struct usb_gadget *gadget)
+{
+ struct tegra_otg_data *tegra;
+ unsigned long val;
+
+ tegra = container_of(otg, struct tegra_otg_data, otg);
+ otg->gadget = gadget;
+
+ clk_enable(tegra->clk);
+ val = otg_readl(tegra, USB_PHY_WAKEUP);
+ val &= ~(USB_VBUS_INT_STATUS | USB_ID_INT_STATUS);
+
+ if (gadget)
+ val |= (USB_VBUS_INT_EN | USB_VBUS_WAKEUP_EN);
+ else
+ val &= ~(USB_VBUS_INT_EN | USB_VBUS_WAKEUP_EN);
+
+ otg_writel(tegra, val, USB_PHY_WAKEUP);
+ clk_disable(tegra->clk);
+
+ return 0;
+}
+
+static int tegra_otg_set_host(struct otg_transceiver *otg,
+ struct usb_bus *host)
+{
+ struct tegra_otg_data *tegra;
+ unsigned long val;
+
+ tegra = container_of(otg, struct tegra_otg_data, otg);
+ otg->host = host;
+
+ clk_enable(tegra->clk);
+ val = otg_readl(tegra, USB_PHY_WAKEUP);
+ val &= ~(USB_VBUS_INT_STATUS | USB_ID_INT_STATUS);
+
+ if (host)
+ val |= USB_ID_INT_EN | USB_ID_PIN_WAKEUP_EN;
+ else
+ val &= ~(USB_ID_INT_EN | USB_ID_PIN_WAKEUP_EN);
+ otg_writel(tegra, val, USB_PHY_WAKEUP);
+ clk_disable(tegra->clk);
+
+ return 0;
+}
+
+static int tegra_otg_set_power(struct otg_transceiver *otg, unsigned mA)
+{
+ return 0;
+}
+
+static int tegra_otg_set_suspend(struct otg_transceiver *otg, int suspend)
+{
+ return 0;
+}
+
+static int tegra_otg_probe(struct platform_device *pdev)
+{
+ struct tegra_otg_data *tegra;
+ struct resource *res;
+ unsigned long val;
+ int err;
+
+ tegra = kzalloc(sizeof(struct tegra_otg_data), GFP_KERNEL);
+ if (!tegra)
+ return -ENOMEM;
+
+ tegra->otg.dev = &pdev->dev;
+ tegra->otg.label = "tegra-otg";
+ tegra->otg.state = OTG_STATE_UNDEFINED;
+ tegra->otg.set_host = tegra_otg_set_host;
+ tegra->otg.set_peripheral = tegra_otg_set_peripheral;
+ tegra->otg.set_suspend = tegra_otg_set_suspend;
+ tegra->otg.set_power = tegra_otg_set_power;
+ tegra->host = pdev->dev.platform_data;
+ spin_lock_init(&tegra->lock);
+
+ platform_set_drvdata(pdev, tegra);
+
+ tegra->clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(tegra->clk)) {
+ dev_err(&pdev->dev, "Can't get otg clock\n");
+ err = PTR_ERR(tegra->clk);
+ goto err_clk;
+ }
+
+ err = clk_enable(tegra->clk);
+ if (err)
+ goto err_clken;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get I/O memory\n");
+ err = -ENXIO;
+ goto err_io;
+ }
+ tegra->regs = ioremap(res->start, resource_size(res));
+ if (!tegra->regs) {
+ err = -ENOMEM;
+ goto err_io;
+ }
+
+ val = otg_readl(tegra, USB_PHY_WAKEUP);
+
+ val &= ~(USB_VBUS_INT_STATUS | USB_VBUS_INT_EN |
+ USB_ID_INT_STATUS | USB_ID_INT_EN |
+ USB_VBUS_WAKEUP_EN | USB_ID_PIN_WAKEUP_EN);
+
+ otg_writel(tegra, val, USB_PHY_WAKEUP);
+
+ tegra->otg.state = OTG_STATE_A_SUSPEND;
+
+ err = otg_set_transceiver(&tegra->otg);
+ if (err) {
+ dev_err(&pdev->dev, "can't register transceiver (%d)\n", err);
+ goto err_otg;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get IRQ\n");
+ err = -ENXIO;
+ goto err_irq;
+ }
+ tegra->irq = res->start;
+ err = request_threaded_irq(tegra->irq, tegra_otg_irq,
+ tegra_otg_irq_thread,
+ IRQF_SHARED, "tegra-otg", tegra);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to register IRQ\n");
+ goto err_irq;
+ }
+
+ dev_info(&pdev->dev, "otg transceiver registered\n");
+ return 0;
+
+err_irq:
+ otg_set_transceiver(NULL);
+err_otg:
+ iounmap(tegra->regs);
+err_io:
+ clk_disable(tegra->clk);
+err_clken:
+ clk_put(tegra->clk);
+err_clk:
+ platform_set_drvdata(pdev, NULL);
+ kfree(tegra);
+ return err;
+}
+
+static int __exit tegra_otg_remove(struct platform_device *pdev)
+{
+ struct tegra_otg_data *tegra = platform_get_drvdata(pdev);
+
+ free_irq(tegra->irq, tegra);
+ otg_set_transceiver(NULL);
+ iounmap(tegra->regs);
+ clk_disable(tegra->clk);
+ clk_put(tegra->clk);
+ platform_set_drvdata(pdev, NULL);
+ kfree(tegra);
+
+ return 0;
+}
+
+static struct platform_driver tegra_otg_driver = {
+ .driver = {
+ .name = "tegra-otg",
+ },
+ .remove = __exit_p(tegra_otg_remove),
+ .probe = tegra_otg_probe,
+};
+
+static int __init tegra_otg_init(void)
+{
+ return platform_driver_register(&tegra_otg_driver);
+}
+subsys_initcall(tegra_otg_init);
+
+static void __exit tegra_otg_exit(void)
+{
+ platform_driver_unregister(&tegra_otg_driver);
+}
+module_exit(tegra_otg_exit);