diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/usb/host/ehci-tegra.c | 604 |
1 files changed, 604 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c new file mode 100644 index 000000000..869d9c4de --- /dev/null +++ b/drivers/usb/host/ehci-tegra.c @@ -0,0 +1,604 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * EHCI-compliant USB host controller driver for NVIDIA Tegra SoCs + * + * Copyright (C) 2010 Google, Inc. + * Copyright (C) 2009 - 2013 NVIDIA Corporation + */ + +#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; + +struct tegra_ehci_soc_config { + bool has_hostpc; +}; + +struct tegra_ehci_hcd { + struct clk *clk; + struct reset_control *rst; + int port_resuming; + bool needs_double_reset; +}; + +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; + struct reset_control *rst; + int err; + + phy_np = of_parse_phandle(pdev->dev.of_node, "nvidia,phy", 0); + if (!phy_np) + return -ENOENT; + + /* + * 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. + */ + rst = of_reset_control_get_shared(phy_np, "utmi-pads"); + if (IS_ERR(rst)) { + 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 { + /* + * PHY driver performs UTMI-pads reset in a case of + * non-legacy DT. + */ + reset_control_put(rst); + } + + of_node_put(phy_np); + + /* reset control is shared, hence initialize it first */ + err = reset_control_deassert(tegra->rst); + if (err) + return err; + + err = reset_control_assert(tegra->rst); + if (err) + return err; + + udelay(1); + + err = reset_control_deassert(tegra->rst); + if (err) + return err; + + 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[]; +}; + +static void free_dma_aligned_buffer(struct urb *urb) +{ + struct dma_aligned_buffer *temp; + size_t length; + + 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)) { + if (usb_pipeisoc(urb->pipe)) + length = urb->transfer_buffer_length; + else + length = urb->actual_length; + + memcpy(temp->old_xfer_buffer, temp->data, 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_shared(&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) { + dev_err(&pdev->dev, "Failed to reset controller\n"); + 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; + hcd->skip_phy_initialization = 1; + + 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); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + err = irq; + 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; + + usb_remove_hcd(hcd); + otg_set_host(hcd->usb_phy->otg, NULL); + usb_phy_shutdown(hcd->usb_phy); + 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); |