--- /dev/null
+/*
+ * EHCI-compliant USB host controller driver for NVIDIA Tegra SoCs
+ *
+ * Copyright (C) 2010 Google, Inc.
+ * Copyright (C) 2009 - 2013 NVIDIA Corporation
+ *
+ * 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.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/usb/ehci_def.h>
+#include <linux/usb/tegra_usb_phy.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/otg.h>
+
+#include "ehci.h"
+
+#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 bool usb1_reset_attempted;
+
+struct tegra_ehci_soc_config {
+ bool has_hostpc;
+};
+
+struct tegra_ehci_hcd {
+ struct tegra_usb_phy *phy;
+ struct clk *clk;
+ struct reset_control *rst;
+ int port_resuming;
+ bool needs_double_reset;
+ enum tegra_usb_phy_port_speed port_speed;
+};
+
+/*
+ * The 1st USB controller contains some UTMI pad registers that are global for
+ * all the controllers on the chip. Those registers are also cleared when
+ * reset is asserted to the 1st controller. This means that the 1st controller
+ * can only be reset when no other controlled has finished probing. So we'll
+ * reset the 1st controller before doing any other setup on any of the
+ * controllers, and then never again.
+ *
+ * Since this is a PHY issue, the Tegra PHY driver should probably be doing
+ * the resetting of the USB controllers. But to keep compatibility with old
+ * device trees that don't have reset phandles in the PHYs, do it here.
+ * Those old DTs will be vulnerable to total USB breakage if the 1st EHCI
+ * device isn't the first one to finish probing, so warn them.
+ */
+static int tegra_reset_usb_controller(struct platform_device *pdev)
+{
+ struct device_node *phy_np;
+ struct usb_hcd *hcd = platform_get_drvdata(pdev);
+ struct tegra_ehci_hcd *tegra =
+ (struct tegra_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+ phy_np = of_parse_phandle(pdev->dev.of_node, "nvidia,phy", 0);
+ if (!phy_np)
+ return -ENOENT;
+
+ if (!usb1_reset_attempted) {
+ struct reset_control *usb1_reset;
+
+ usb1_reset = of_reset_control_get(phy_np, "usb");
+ if (IS_ERR(usb1_reset)) {
+ dev_warn(&pdev->dev,
+ "can't get utmi-pads reset from the PHY\n");
+ dev_warn(&pdev->dev,
+ "continuing, but please update your DT\n");
+ } else {
+ reset_control_assert(usb1_reset);
+ udelay(1);
+ reset_control_deassert(usb1_reset);
+ }
+
+ reset_control_put(usb1_reset);
+ usb1_reset_attempted = true;
+ }
+
+ if (!of_property_read_bool(phy_np, "nvidia,has-utmi-pad-registers")) {
+ reset_control_assert(tegra->rst);
+ udelay(1);
+ reset_control_deassert(tegra->rst);
+ }
+
+ of_node_put(phy_np);
+
+ return 0;
+}
+
+static int tegra_ehci_internal_port_reset(
+ struct ehci_hcd *ehci,
+ u32 __iomem *portsc_reg
+)
+{
+ u32 temp;
+ unsigned long flags;
+ int retval = 0;
+ int i, tries;
+ u32 saved_usbintr;
+
+ spin_lock_irqsave(&ehci->lock, flags);
+ saved_usbintr = ehci_readl(ehci, &ehci->regs->intr_enable);
+ /* disable USB interrupt */
+ ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+ spin_unlock_irqrestore(&ehci->lock, flags);
+
+ /*
+ * Here we have to do Port Reset at most twice for
+ * Port Enable bit to be set.
+ */
+ for (i = 0; i < 2; i++) {
+ temp = ehci_readl(ehci, portsc_reg);
+ temp |= PORT_RESET;
+ ehci_writel(ehci, temp, portsc_reg);
+ mdelay(10);
+ temp &= ~PORT_RESET;
+ ehci_writel(ehci, temp, portsc_reg);
+ mdelay(1);
+ tries = 100;
+ do {
+ mdelay(1);
+ /*
+ * Up to this point, Port Enable bit is
+ * expected to be set after 2 ms waiting.
+ * USB1 usually takes extra 45 ms, for safety,
+ * we take 100 ms as timeout.
+ */
+ temp = ehci_readl(ehci, portsc_reg);
+ } while (!(temp & PORT_PE) && tries--);
+ if (temp & PORT_PE)
+ break;
+ }
+ if (i == 2)
+ retval = -ETIMEDOUT;
+
+ /*
+ * Clear Connect Status Change bit if it's set.
+ * We can't clear PORT_PEC. It will also cause PORT_PE to be cleared.
+ */
+ if (temp & PORT_CSC)
+ ehci_writel(ehci, PORT_CSC, portsc_reg);
+
+ /*
+ * Write to clear any interrupt status bits that might be set
+ * during port reset.
+ */
+ temp = ehci_readl(ehci, &ehci->regs->status);
+ ehci_writel(ehci, temp, &ehci->regs->status);
+
+ /* restore original interrupt enable bits */
+ ehci_writel(ehci, saved_usbintr, &ehci->regs->intr_enable);
+ return retval;
+}
+
+static int tegra_ehci_hub_control(
+ struct usb_hcd *hcd,
+ u16 typeReq,
+ u16 wValue,
+ u16 wIndex,
+ char *buf,
+ u16 wLength
+)
+{
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ struct tegra_ehci_hcd *tegra = (struct tegra_ehci_hcd *)ehci->priv;
+ u32 __iomem *status_reg;
+ u32 temp;
+ unsigned long flags;
+ int retval = 0;
+
+ status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];
+
+ spin_lock_irqsave(&ehci->lock, flags);
+
+ if (typeReq == GetPortStatus) {
+ temp = ehci_readl(ehci, status_reg);
+ if (tegra->port_resuming && !(temp & PORT_SUSPEND)) {
+ /* Resume completed, re-enable disconnect detection */
+ tegra->port_resuming = 0;
+ tegra_usb_phy_postresume(hcd->usb_phy);
+ }
+ }
+
+ else if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
+ temp = ehci_readl(ehci, status_reg);
+ if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
+ retval = -EPIPE;
+ goto done;
+ }
+
+ temp &= ~(PORT_RWC_BITS | PORT_WKCONN_E);
+ temp |= PORT_WKDISC_E | PORT_WKOC_E;
+ ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
+
+ /*
+ * If a transaction is in progress, there may be a delay in
+ * suspending the port. Poll until the port is suspended.
+ */
+ if (ehci_handshake(ehci, status_reg, PORT_SUSPEND,
+ PORT_SUSPEND, 5000))
+ pr_err("%s: timeout waiting for SUSPEND\n", __func__);
+
+ set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
+ goto done;
+ }
+
+ /* For USB1 port we need to issue Port Reset twice internally */
+ if (tegra->needs_double_reset &&
+ (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_RESET)) {
+ spin_unlock_irqrestore(&ehci->lock, flags);
+ return tegra_ehci_internal_port_reset(ehci, status_reg);
+ }
+
+ /*
+ * Tegra host controller will time the resume operation to clear the bit
+ * when the port control state switches to HS or FS Idle. This behavior
+ * is different from EHCI where the host controller driver is required
+ * to set this bit to a zero after the resume duration is timed in the
+ * driver.
+ */
+ else if (typeReq == ClearPortFeature &&
+ wValue == USB_PORT_FEAT_SUSPEND) {
+ temp = ehci_readl(ehci, status_reg);
+ if ((temp & PORT_RESET) || !(temp & PORT_PE)) {
+ retval = -EPIPE;
+ goto done;
+ }
+
+ if (!(temp & PORT_SUSPEND))
+ goto done;
+
+ /* Disable disconnect detection during port resume */
+ tegra_usb_phy_preresume(hcd->usb_phy);
+
+ ehci->reset_done[wIndex-1] = jiffies + msecs_to_jiffies(25);
+
+ temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
+ /* start resume signalling */
+ ehci_writel(ehci, temp | PORT_RESUME, status_reg);
+ set_bit(wIndex-1, &ehci->resuming_ports);
+
+ spin_unlock_irqrestore(&ehci->lock, flags);
+ msleep(20);
+ spin_lock_irqsave(&ehci->lock, flags);
+
+ /* Poll until the controller clears RESUME and SUSPEND */
+ if (ehci_handshake(ehci, status_reg, PORT_RESUME, 0, 2000))
+ pr_err("%s: timeout waiting for RESUME\n", __func__);
+ if (ehci_handshake(ehci, status_reg, PORT_SUSPEND, 0, 2000))
+ pr_err("%s: timeout waiting for SUSPEND\n", __func__);
+
+ ehci->reset_done[wIndex-1] = 0;
+ clear_bit(wIndex-1, &ehci->resuming_ports);
+
+ tegra->port_resuming = 1;
+ goto done;
+ }
+
+ spin_unlock_irqrestore(&ehci->lock, flags);
+
+ /* Handle the hub control events here */
+ return ehci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
+
+done:
+ spin_unlock_irqrestore(&ehci->lock, flags);
+ return retval;
+}
+
+struct dma_aligned_buffer {
+ void *kmalloc_ptr;
+ void *old_xfer_buffer;
+ u8 data[0];
+};
+
+static void free_dma_aligned_buffer(struct urb *urb)
+{
+ struct dma_aligned_buffer *temp;
+
+ if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
+ return;
+
+ temp = container_of(urb->transfer_buffer,
+ struct dma_aligned_buffer, data);
+
+ if (usb_urb_dir_in(urb))
+ memcpy(temp->old_xfer_buffer, temp->data,
+ urb->transfer_buffer_length);
+ urb->transfer_buffer = temp->old_xfer_buffer;
+ kfree(temp->kmalloc_ptr);
+
+ urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
+}
+
+static int alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
+{
+ struct dma_aligned_buffer *temp, *kmalloc_ptr;
+ size_t kmalloc_size;
+
+ if (urb->num_sgs || urb->sg ||
+ urb->transfer_buffer_length == 0 ||
+ !((uintptr_t)urb->transfer_buffer & (TEGRA_USB_DMA_ALIGN - 1)))
+ return 0;
+
+ /* Allocate a buffer with enough padding for alignment */
+ kmalloc_size = urb->transfer_buffer_length +
+ sizeof(struct dma_aligned_buffer) + TEGRA_USB_DMA_ALIGN - 1;
+
+ kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
+ if (!kmalloc_ptr)
+ return -ENOMEM;
+
+ /* Position our struct dma_aligned_buffer such that data is aligned */
+ temp = PTR_ALIGN(kmalloc_ptr + 1, TEGRA_USB_DMA_ALIGN) - 1;
+ temp->kmalloc_ptr = kmalloc_ptr;
+ temp->old_xfer_buffer = urb->transfer_buffer;
+ if (usb_urb_dir_out(urb))
+ memcpy(temp->data, urb->transfer_buffer,
+ urb->transfer_buffer_length);
+ urb->transfer_buffer = temp->data;
+
+ urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
+
+ return 0;
+}
+
+static int tegra_ehci_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
+ gfp_t mem_flags)
+{
+ int ret;
+
+ ret = alloc_dma_aligned_buffer(urb, mem_flags);
+ if (ret)
+ return ret;
+
+ ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
+ if (ret)
+ free_dma_aligned_buffer(urb);
+
+ return ret;
+}
+
+static void tegra_ehci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+ usb_hcd_unmap_urb_for_dma(hcd, urb);
+ free_dma_aligned_buffer(urb);
+}
+
+static const struct tegra_ehci_soc_config tegra30_soc_config = {
+ .has_hostpc = true,
+};
+
+static const struct tegra_ehci_soc_config tegra20_soc_config = {
+ .has_hostpc = false,
+};
+
+static const struct of_device_id tegra_ehci_of_match[] = {
+ { .compatible = "nvidia,tegra30-ehci", .data = &tegra30_soc_config },
+ { .compatible = "nvidia,tegra20-ehci", .data = &tegra20_soc_config },
+ { },
+};
+
+static int tegra_ehci_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+ const struct tegra_ehci_soc_config *soc_config;
+ struct resource *res;
+ struct usb_hcd *hcd;
+ struct ehci_hcd *ehci;
+ struct tegra_ehci_hcd *tegra;
+ int err = 0;
+ int irq;
+ struct usb_phy *u_phy;
+
+ match = of_match_device(tegra_ehci_of_match, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+ soc_config = match->data;
+
+ /* Right now device-tree probed devices don't get dma_mask set.
+ * Since shared usb code relies on it, set it here for now.
+ * Once we have dma capability bindings this can go away.
+ */
+ err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+ if (err)
+ return err;
+
+ hcd = usb_create_hcd(&tegra_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);
+ ehci = hcd_to_ehci(hcd);
+ tegra = (struct tegra_ehci_hcd *)ehci->priv;
+
+ hcd->has_tt = 1;
+
+ tegra->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(tegra->clk)) {
+ dev_err(&pdev->dev, "Can't get ehci clock\n");
+ err = PTR_ERR(tegra->clk);
+ goto cleanup_hcd_create;
+ }
+
+ tegra->rst = devm_reset_control_get(&pdev->dev, "usb");
+ if (IS_ERR(tegra->rst)) {
+ dev_err(&pdev->dev, "Can't get ehci reset\n");
+ err = PTR_ERR(tegra->rst);
+ goto cleanup_hcd_create;
+ }
+
+ err = clk_prepare_enable(tegra->clk);
+ if (err)
+ goto cleanup_hcd_create;
+
+ err = tegra_reset_usb_controller(pdev);
+ if (err)
+ goto cleanup_clk_en;
+
+ u_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0);
+ if (IS_ERR(u_phy)) {
+ err = -EPROBE_DEFER;
+ goto cleanup_clk_en;
+ }
+ hcd->usb_phy = u_phy;
+
+ tegra->needs_double_reset = of_property_read_bool(pdev->dev.of_node,
+ "nvidia,needs-double-reset");
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ hcd->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(hcd->regs)) {
+ err = PTR_ERR(hcd->regs);
+ goto cleanup_clk_en;
+ }
+ hcd->rsrc_start = res->start;
+ hcd->rsrc_len = resource_size(res);
+
+ ehci->caps = hcd->regs + 0x100;
+ ehci->has_hostpc = soc_config->has_hostpc;
+
+ err = usb_phy_init(hcd->usb_phy);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to initialize phy\n");
+ goto cleanup_clk_en;
+ }
+
+ u_phy->otg = devm_kzalloc(&pdev->dev, sizeof(struct usb_otg),
+ GFP_KERNEL);
+ if (!u_phy->otg) {
+ err = -ENOMEM;
+ goto cleanup_phy;
+ }
+ u_phy->otg->host = hcd_to_bus(hcd);
+
+ err = usb_phy_set_suspend(hcd->usb_phy, 0);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to power on the phy\n");
+ goto cleanup_phy;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (!irq) {
+ dev_err(&pdev->dev, "Failed to get IRQ\n");
+ err = -ENODEV;
+ goto cleanup_phy;
+ }
+
+ otg_set_host(u_phy->otg, &hcd->self);
+
+ err = usb_add_hcd(hcd, irq, IRQF_SHARED);
+ if (err) {
+ dev_err(&pdev->dev, "Failed to add USB HCD\n");
+ goto cleanup_otg_set_host;
+ }
+ device_wakeup_enable(hcd->self.controller);
+
+ return err;
+
+cleanup_otg_set_host:
+ otg_set_host(u_phy->otg, NULL);
+cleanup_phy:
+ usb_phy_shutdown(hcd->usb_phy);
+cleanup_clk_en:
+ clk_disable_unprepare(tegra->clk);
+cleanup_hcd_create:
+ usb_put_hcd(hcd);
+ return err;
+}
+
+static int tegra_ehci_remove(struct platform_device *pdev)
+{
+ struct usb_hcd *hcd = platform_get_drvdata(pdev);
+ struct tegra_ehci_hcd *tegra =
+ (struct tegra_ehci_hcd *)hcd_to_ehci(hcd)->priv;
+
+ otg_set_host(hcd->usb_phy->otg, NULL);
+
+ usb_phy_shutdown(hcd->usb_phy);
+ usb_remove_hcd(hcd);
+
+ clk_disable_unprepare(tegra->clk);
+
+ usb_put_hcd(hcd);
+
+ return 0;
+}
+
+static void tegra_ehci_hcd_shutdown(struct platform_device *pdev)
+{
+ struct usb_hcd *hcd = platform_get_drvdata(pdev);
+
+ if (hcd->driver->shutdown)
+ hcd->driver->shutdown(hcd);
+}
+
+static struct platform_driver tegra_ehci_driver = {
+ .probe = tegra_ehci_probe,
+ .remove = tegra_ehci_remove,
+ .shutdown = tegra_ehci_hcd_shutdown,
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = tegra_ehci_of_match,
+ }
+};
+
+static int tegra_ehci_reset(struct usb_hcd *hcd)
+{
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ int retval;
+ int txfifothresh;
+
+ retval = ehci_setup(hcd);
+ if (retval)
+ return retval;
+
+ /*
+ * We should really pull this value out of tegra_ehci_soc_config, but
+ * to avoid needing access to it, make use of the fact that Tegra20 is
+ * the only one so far that needs a value of 10, and Tegra20 is the
+ * only one which doesn't set has_hostpc.
+ */
+ txfifothresh = ehci->has_hostpc ? 0x10 : 10;
+ ehci_writel(ehci, txfifothresh << 16, &ehci->regs->txfill_tuning);
+
+ return 0;
+}
+
+static const struct ehci_driver_overrides tegra_overrides __initconst = {
+ .extra_priv_size = sizeof(struct tegra_ehci_hcd),
+ .reset = tegra_ehci_reset,
+};
+
+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.
+ */
+
+ 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);
Code Review / kvmfornfv.git / blobdiff