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Release 4.11 drivers/usb/host/ehci-tegra.c

Directory: drivers/usb/host
/*
 * 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; bool has_utmi_pad_registers = false; phy_np = of_parse_phandle(pdev->dev.of_node, "nvidia,phy", 0); if (!phy_np) return -ENOENT; if (of_property_read_bool(phy_np, "nvidia,has-utmi-pad-registers")) has_utmi_pad_registers = true; if (!usb1_reset_attempted) { struct reset_control *usb1_reset; if (!has_utmi_pad_registers) usb1_reset = of_reset_control_get(phy_np, "utmi-pads"); else usb1_reset = tegra->rst; 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); if (!has_utmi_pad_registers) reset_control_put(usb1_reset); } usb1_reset_attempted = true; } if (!has_utmi_pad_registers) { reset_control_assert(tegra->rst); udelay(1); reset_control_deassert(tegra->rst); } of_node_put(phy_np); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Tuomas Tynkkynen17582.16%133.33%
Thierry Reding3817.84%266.67%
Total213100.00%3100.00%


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; }

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PersonTokensPropCommitsCommitProp
Jim Lin263100.00%1100.00%
Total263100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby47885.66%110.00%
Jim Lin366.45%110.00%
Alan Stern244.30%110.00%
Stephen Warren111.97%220.00%
Manjunath Goudar30.54%110.00%
Venu Byravarasu30.54%220.00%
Antoine Ténart20.36%110.00%
Laurent Pinchart10.18%110.00%
Total558100.00%10100.00%

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; 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; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Stern5650.45%125.00%
Johan Hovold2825.23%125.00%
Benoit Goby2219.82%125.00%
Greg Kroah-Hartman54.50%125.00%
Total111100.00%4100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Alan Stern11872.84%133.33%
Benoit Goby3823.46%133.33%
Greg Kroah-Hartman63.70%133.33%
Total162100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby3659.02%133.33%
Alan Stern2337.70%133.33%
Greg Kroah-Hartman23.28%133.33%
Total61100.00%3100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby1657.14%133.33%
Alan Stern1139.29%133.33%
Greg Kroah-Hartman13.57%133.33%
Total28100.00%3100.00%

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; }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby27039.53%13.45%
Stephen Warren14120.64%310.34%
Venu Byravarasu10515.37%620.69%
Tuomas Tynkkynen7711.27%413.79%
Varka Bhadram172.49%13.45%
Russell King121.76%26.90%
Julia Lawall111.61%13.45%
Manjunath Goudar101.46%13.45%
Peter Chen91.32%13.45%
Vivek Gautam91.32%13.45%
Olof Johansson60.88%13.45%
Heikki Krogerus40.59%13.45%
Antoine Ténart40.59%13.45%
Thierry Reding20.29%13.45%
Vince Hsu20.29%13.45%
Mikko Perttunen20.29%13.45%
Wei Yongjun10.15%13.45%
Prashant Gaikwad10.15%13.45%
Total683100.00%29100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby4863.16%111.11%
Stephen Warren1317.11%111.11%
Tuomas Tynkkynen67.89%222.22%
Venu Byravarasu33.95%111.11%
Heikki Krogerus22.63%111.11%
Antoine Ténart22.63%111.11%
Prashant Gaikwad11.32%111.11%
Alan Stern11.32%111.11%
Total76100.00%9100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby3694.74%150.00%
Stephen Warren25.26%150.00%
Total38100.00%2100.00%

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; }

Contributors

PersonTokensPropCommitsCommitProp
Stephen Warren71100.00%1100.00%
Total71100.00%1100.00%

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); }

Contributors

PersonTokensPropCommitsCommitProp
Manjunath Goudar61100.00%1100.00%
Total61100.00%1100.00%

module_init(ehci_tegra_init);
static void __exit ehci_tegra_cleanup(void) { platform_driver_unregister(&tegra_ehci_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Manjunath Goudar15100.00%1100.00%
Total15100.00%1100.00%

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);

Overall Contributors

PersonTokensPropCommitsCommitProp
Benoit Goby100938.21%12.27%
Tuomas Tynkkynen33612.72%511.36%
Jim Lin29911.32%12.27%
Alan Stern2549.62%24.55%
Stephen Warren2529.54%613.64%
Manjunath Goudar1836.93%24.55%
Venu Byravarasu1214.58%613.64%
Thierry Reding401.51%36.82%
Johan Hovold281.06%12.27%
Olof Johansson190.72%12.27%
Varka Bhadram170.64%12.27%
Greg Kroah-Hartman150.57%12.27%
Russell King120.45%24.55%
Julia Lawall110.42%12.27%
Peter Chen90.34%12.27%
Vivek Gautam90.34%12.27%
Antoine Ténart80.30%12.27%
Heikki Krogerus60.23%12.27%
Robert Morell40.15%12.27%
Vince Hsu20.08%12.27%
Mikko Perttunen20.08%12.27%
Prashant Gaikwad20.08%12.27%
Wei Yongjun10.04%12.27%
Jingoo Han10.04%12.27%
Laurent Pinchart10.04%12.27%
Total2641100.00%44100.00%
Directory: drivers/usb/host
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