usb: add OTG driver for tegra USB PHY
Gary King [Tue, 28 Sep 2010 19:32:13 +0000 (12:32 -0700)]
Change-Id: I23be62e819b658c0e25f70eebfbb8dc0dc76c173
Signed-off-by: Gary King <gking@nvidia.com>

drivers/usb/otg/Kconfig
drivers/usb/otg/Makefile
drivers/usb/otg/tegra-otg.c [new file with mode: 0644]

index c66481a..226bd76 100644 (file)
@@ -113,6 +113,14 @@ config USB_MSM_OTG
          This driver is not supported on boards like trout which
          has an external PHY.
 
+config USB_TEGRA_OTG
+       boolean "Tegra OTG Driver"
+       depends on USB && ARCH_TEGRA
+       select USB_OTG_UTILS
+       help
+         Enable this driver on boards which use the internal VBUS and ID
+         sensing of the Tegra USB PHY.
+
 config AB8500_USB
         tristate "AB8500 USB Transceiver Driver"
         depends on AB8500_CORE
index 566655c..63b39bd 100644 (file)
@@ -10,6 +10,7 @@ obj-$(CONFIG_USB_OTG_UTILS)   += otg.o
 
 # transceiver drivers
 obj-$(CONFIG_USB_GPIO_VBUS)    += gpio_vbus.o
+obj-$(CONFIG_USB_TEGRA_OTG)    += tegra-otg.o
 obj-$(CONFIG_ISP1301_OMAP)     += isp1301_omap.o
 obj-$(CONFIG_TWL4030_USB)      += twl4030-usb.o
 obj-$(CONFIG_TWL6030_USB)      += twl6030-usb.o
diff --git a/drivers/usb/otg/tegra-otg.c b/drivers/usb/otg/tegra-otg.c
new file mode 100644 (file)
index 0000000..542a184
--- /dev/null
@@ -0,0 +1,393 @@
+/*
+ * 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);