USB: EHCI: make ehci-tegra a separate driver

Separate the Tegra on-chip host controller driver from
ehci-hcd host code so that it can be built as a separate driver module.
This work is part of enabling multi-platform kernels on ARM.

Signed-off-by: Manjunath Goudar <manjunath.goudar@linaro.org>
[swarren, reworked Manjunath's patches to split them more logically,
minor re-order of added lines to better match layout of other split-up
HCD drivers and existing code, add MODULE_DEVICE_TABLE, fix
MODULE_LICENSE, adapted to change in earlier patches which removed the
ehci_driver_overrides addition, removed all PM code and solved circular
dependencies.]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 76 insertions, 60 deletions

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 881609ef85e8..7d0aa5f58f7a 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -198,7 +198,7 @@ config USB_EHCI_MSM
           has an external PHY.
 
 config USB_EHCI_TEGRA
-       boolean "NVIDIA Tegra HCD support"
+       tristate "NVIDIA Tegra HCD support"
        depends on ARCH_TEGRA
        select USB_EHCI_ROOT_HUB_TT
        select USB_PHY
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index b41fa5f9c279..bea71127b15f 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_USB_EHCI_HCD_SPEAR)	+= ehci-spear.o
 obj-$(CONFIG_USB_EHCI_S5P)      += ehci-s5p.o
 obj-$(CONFIG_USB_EHCI_HCD_AT91) += ehci-atmel.o
 obj-$(CONFIG_USB_EHCI_MSM)      += ehci-msm.o
+obj-$(CONFIG_USB_EHCI_TEGRA)    += ehci-tegra.o
 
 obj-$(CONFIG_USB_OXU210HP_HCD)  += oxu210hp-hcd.o
 obj-$(CONFIG_USB_ISP116X_HCD)   += isp116x-hcd.o
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index e8a6f3dd7357..7abf1ce3a670 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1269,11 +1269,6 @@ MODULE_LICENSE ("GPL");
 #define PLATFORM_DRIVER         ehci_hcd_msp_driver
 #endif
 
-#ifdef CONFIG_USB_EHCI_TEGRA
-#include "ehci-tegra.c"
-#define PLATFORM_DRIVER         tegra_ehci_driver
-#endif
-
 #ifdef CONFIG_SPARC_LEON
 #include "ehci-grlib.c"
 #define PLATFORM_DRIVER         ehci_grlib_driver
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index 80634292efee..338c8a56118d 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -17,25 +17,44 @@
  */
 
 #include <linux/clk.h>
+#include <linux/clk/tegra.h>
+#include <linux/dma-mapping.h>
 #include <linux/err.h>
-#include <linux/platform_device.h>
-#include <linux/platform_data/tegra_usb.h>
-#include <linux/irq.h>
-#include <linux/usb/otg.h>
 #include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/tegra_usb.h>
 #include <linux/pm_runtime.h>
+#include <linux/slab.h>
 #include <linux/usb/ehci_def.h>
 #include <linux/usb/tegra_usb_phy.h>
-#include <linux/clk/tegra.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/otg.h>
+
+#include "ehci.h"
 
 #define TEGRA_USB_BASE                  0xC5000000
 #define TEGRA_USB2_BASE                 0xC5004000
 #define TEGRA_USB3_BASE                 0xC5008000
 
+#define PORT_WAKE_BITS (PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E)
+
 #define TEGRA_USB_DMA_ALIGN 32
 
+#define DRIVER_DESC "Tegra EHCI driver"
+#define DRV_NAME "tegra-ehci"
+
+static struct hc_driver __read_mostly tegra_ehci_hc_driver;
+
+static int (*orig_hub_control)(struct usb_hcd *hcd,
+                                u16 typeReq, u16 wValue, u16 wIndex,
+                                char *buf, u16 wLength);
+
 struct tegra_ehci_hcd {
         struct ehci_hcd *ehci;
         struct tegra_usb_phy *phy;
@@ -218,25 +237,13 @@ static int tegra_ehci_hub_control(
         spin_unlock_irqrestore(&ehci->lock, flags);
 
         /* Handle the hub control events here */
-        return ehci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
+        return orig_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
+
 done:
         spin_unlock_irqrestore(&ehci->lock, flags);
         return retval;
 }
 
-static int tegra_ehci_setup(struct usb_hcd *hcd)
-{
-        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
-
-        /* EHCI registers start at offset 0x100 */
-        ehci->caps = hcd->regs + 0x100;
-
-        /* switch to host mode */
-        hcd->has_tt = 1;
-
-        return ehci_setup(hcd);
-}
-
 struct dma_aligned_buffer {
         void *kmalloc_ptr;
         void *old_xfer_buffer;
@@ -316,38 +323,6 @@ static void tegra_ehci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
         free_dma_aligned_buffer(urb);
 }
 
-static const struct hc_driver tegra_ehci_hc_driver = {
-        .description            = hcd_name,
-        .product_desc           = "Tegra EHCI Host Controller",
-        .hcd_priv_size          = sizeof(struct ehci_hcd),
-        .flags                  = HCD_USB2 | HCD_MEMORY,
-
-        /* standard ehci functions */
-        .irq                    = ehci_irq,
-        .start                  = ehci_run,
-        .stop                   = ehci_stop,
-        .urb_enqueue            = ehci_urb_enqueue,
-        .urb_dequeue            = ehci_urb_dequeue,
-        .endpoint_disable       = ehci_endpoint_disable,
-        .endpoint_reset         = ehci_endpoint_reset,
-        .get_frame_number       = ehci_get_frame,
-        .hub_status_data        = ehci_hub_status_data,
-        .clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
-        .relinquish_port        = ehci_relinquish_port,
-        .port_handed_over       = ehci_port_handed_over,
-
-        /* modified ehci functions for tegra */
-        .reset                  = tegra_ehci_setup,
-        .shutdown               = ehci_shutdown,
-        .map_urb_for_dma        = tegra_ehci_map_urb_for_dma,
-        .unmap_urb_for_dma      = tegra_ehci_unmap_urb_for_dma,
-        .hub_control            = tegra_ehci_hub_control,
-#ifdef CONFIG_PM
-        .bus_suspend            = ehci_bus_suspend,
-        .bus_resume             = ehci_bus_resume,
-#endif
-};
-
 static int setup_vbus_gpio(struct platform_device *pdev,
                            struct tegra_ehci_platform_data *pdata)
 {
@@ -444,6 +419,9 @@ static int tegra_ehci_probe(struct platform_device *pdev)
                 err = -ENOMEM;
                 goto cleanup_clk;
         }
+        tegra->ehci = hcd_to_ehci(hcd);
+
+        hcd->has_tt = 1;
         hcd->phy = u_phy;
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -460,6 +438,7 @@ static int tegra_ehci_probe(struct platform_device *pdev)
                 err = -ENOMEM;
                 goto cleanup_hcd_create;
         }
+        tegra->ehci->caps = hcd->regs + 0x100;
 
         err = usb_phy_init(hcd->phy);
         if (err) {
@@ -482,8 +461,6 @@ static int tegra_ehci_probe(struct platform_device *pdev)
                 goto cleanup_phy;
         }
 
-        tegra->ehci = hcd_to_ehci(hcd);
-
         irq = platform_get_irq(pdev, 0);
         if (!irq) {
                 dev_err(&pdev->dev, "Failed to get IRQ\n");
@@ -558,7 +535,50 @@ static struct platform_driver tegra_ehci_driver = {
         .remove         = tegra_ehci_remove,
         .shutdown       = tegra_ehci_hcd_shutdown,
         .driver         = {
-                .name   = "tegra-ehci",
+                .name   = DRV_NAME,
                 .of_match_table = tegra_ehci_of_match,
         }
 };
+
+static const struct ehci_driver_overrides tegra_overrides __initconst = {
+        .extra_priv_size        = sizeof(struct tegra_ehci_hcd),
+};
+
+static int __init ehci_tegra_init(void)
+{
+        if (usb_disabled())
+                return -ENODEV;
+
+        pr_info(DRV_NAME ": " DRIVER_DESC "\n");
+
+        ehci_init_driver(&tegra_ehci_hc_driver, &tegra_overrides);
+
+        /*
+         * The Tegra HW has some unusual quirks, which require Tegra-specific
+         * workarounds. We override certain hc_driver functions here to
+         * achieve that. We explicitly do not enhance ehci_driver_overrides to
+         * allow this more easily, since this is an unusual case, and we don't
+         * want to encourage others to override these functions by making it
+         * too easy.
+         */
+
+        orig_hub_control = tegra_ehci_hc_driver.hub_control;
+
+        tegra_ehci_hc_driver.map_urb_for_dma = tegra_ehci_map_urb_for_dma;
+        tegra_ehci_hc_driver.unmap_urb_for_dma = tegra_ehci_unmap_urb_for_dma;
+        tegra_ehci_hc_driver.hub_control = tegra_ehci_hub_control;
+
+        return platform_driver_register(&tegra_ehci_driver);
+}
+module_init(ehci_tegra_init);
+
+static void __exit ehci_tegra_cleanup(void)
+{
+        platform_driver_unregister(&tegra_ehci_driver);
+}
+module_exit(ehci_tegra_cleanup);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DEVICE_TABLE(of, tegra_ehci_of_match);