linux/drivers/usb/dwc3/dwc3-keystone.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * dwc3-keystone.c - Keystone Specific Glue layer
   4 *
   5 * Copyright (C) 2010-2013 Texas Instruments Incorporated - https://www.ti.com
   6 *
   7 * Author: WingMan Kwok <w-kwok2@ti.com>
   8 */
   9
  10#include <linux/module.h>
  11#include <linux/kernel.h>
  12#include <linux/interrupt.h>
  13#include <linux/platform_device.h>
  14#include <linux/dma-mapping.h>
  15#include <linux/io.h>
  16#include <linux/of_platform.h>
  17#include <linux/phy/phy.h>
  18#include <linux/pm_runtime.h>
  19
  20/* USBSS register offsets */
  21#define USBSS_REVISION          0x0000
  22#define USBSS_SYSCONFIG         0x0010
  23#define USBSS_IRQ_EOI           0x0018
  24#define USBSS_IRQSTATUS_RAW_0   0x0020
  25#define USBSS_IRQSTATUS_0       0x0024
  26#define USBSS_IRQENABLE_SET_0   0x0028
  27#define USBSS_IRQENABLE_CLR_0   0x002c
  28
  29/* IRQ register bits */
  30#define USBSS_IRQ_EOI_LINE(n)   BIT(n)
  31#define USBSS_IRQ_EVENT_ST      BIT(0)
  32#define USBSS_IRQ_COREIRQ_EN    BIT(0)
  33#define USBSS_IRQ_COREIRQ_CLR   BIT(0)
  34
  35struct dwc3_keystone {
  36        struct device                   *dev;
  37        void __iomem                    *usbss;
  38        struct phy                      *usb3_phy;
  39};
  40
  41static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
  42{
  43        return readl(base + offset);
  44}
  45
  46static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
  47{
  48        writel(value, base + offset);
  49}
  50
  51static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
  52{
  53        u32 val;
  54
  55        val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  56        val |= USBSS_IRQ_COREIRQ_EN;
  57        kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  58}
  59
  60static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
  61{
  62        u32 val;
  63
  64        val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  65        val &= ~USBSS_IRQ_COREIRQ_EN;
  66        kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  67}
  68
  69static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
  70{
  71        struct dwc3_keystone    *kdwc = _kdwc;
  72
  73        kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
  74        kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
  75        kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
  76        kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
  77
  78        return IRQ_HANDLED;
  79}
  80
  81static int kdwc3_probe(struct platform_device *pdev)
  82{
  83        struct device           *dev = &pdev->dev;
  84        struct device_node      *node = pdev->dev.of_node;
  85        struct dwc3_keystone    *kdwc;
  86        int                     error, irq;
  87
  88        kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
  89        if (!kdwc)
  90                return -ENOMEM;
  91
  92        platform_set_drvdata(pdev, kdwc);
  93
  94        kdwc->dev = dev;
  95
  96        kdwc->usbss = devm_platform_ioremap_resource(pdev, 0);
  97        if (IS_ERR(kdwc->usbss))
  98                return PTR_ERR(kdwc->usbss);
  99
 100        /* PSC dependency on AM65 needs SERDES0 to be powered before USB0 */
 101        kdwc->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
 102        if (IS_ERR(kdwc->usb3_phy))
 103                return dev_err_probe(dev, PTR_ERR(kdwc->usb3_phy), "couldn't get usb3 phy\n");
 104
 105        phy_pm_runtime_get_sync(kdwc->usb3_phy);
 106
 107        error = phy_reset(kdwc->usb3_phy);
 108        if (error < 0) {
 109                dev_err(dev, "usb3 phy reset failed: %d\n", error);
 110                return error;
 111        }
 112
 113        error = phy_init(kdwc->usb3_phy);
 114        if (error < 0) {
 115                dev_err(dev, "usb3 phy init failed: %d\n", error);
 116                return error;
 117        }
 118
 119        error = phy_power_on(kdwc->usb3_phy);
 120        if (error < 0) {
 121                dev_err(dev, "usb3 phy power on failed: %d\n", error);
 122                phy_exit(kdwc->usb3_phy);
 123                return error;
 124        }
 125
 126        pm_runtime_enable(kdwc->dev);
 127        error = pm_runtime_get_sync(kdwc->dev);
 128        if (error < 0) {
 129                dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
 130                        error);
 131                goto err_irq;
 132        }
 133
 134        /* IRQ processing not required currently for AM65 */
 135        if (of_device_is_compatible(node, "ti,am654-dwc3"))
 136                goto skip_irq;
 137
 138        irq = platform_get_irq(pdev, 0);
 139        if (irq < 0) {
 140                error = irq;
 141                goto err_irq;
 142        }
 143
 144        error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
 145                        dev_name(dev), kdwc);
 146        if (error) {
 147                dev_err(dev, "failed to request IRQ #%d --> %d\n",
 148                                irq, error);
 149                goto err_irq;
 150        }
 151
 152        kdwc3_enable_irqs(kdwc);
 153
 154skip_irq:
 155        error = of_platform_populate(node, NULL, NULL, dev);
 156        if (error) {
 157                dev_err(&pdev->dev, "failed to create dwc3 core\n");
 158                goto err_core;
 159        }
 160
 161        return 0;
 162
 163err_core:
 164        kdwc3_disable_irqs(kdwc);
 165err_irq:
 166        pm_runtime_put_sync(kdwc->dev);
 167        pm_runtime_disable(kdwc->dev);
 168        phy_power_off(kdwc->usb3_phy);
 169        phy_exit(kdwc->usb3_phy);
 170        phy_pm_runtime_put_sync(kdwc->usb3_phy);
 171
 172        return error;
 173}
 174
 175static int kdwc3_remove_core(struct device *dev, void *c)
 176{
 177        struct platform_device *pdev = to_platform_device(dev);
 178
 179        platform_device_unregister(pdev);
 180
 181        return 0;
 182}
 183
 184static int kdwc3_remove(struct platform_device *pdev)
 185{
 186        struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
 187        struct device_node *node = pdev->dev.of_node;
 188
 189        if (!of_device_is_compatible(node, "ti,am654-dwc3"))
 190                kdwc3_disable_irqs(kdwc);
 191
 192        device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
 193        pm_runtime_put_sync(kdwc->dev);
 194        pm_runtime_disable(kdwc->dev);
 195
 196        phy_power_off(kdwc->usb3_phy);
 197        phy_exit(kdwc->usb3_phy);
 198        phy_pm_runtime_put_sync(kdwc->usb3_phy);
 199
 200        platform_set_drvdata(pdev, NULL);
 201
 202        return 0;
 203}
 204
 205static const struct of_device_id kdwc3_of_match[] = {
 206        { .compatible = "ti,keystone-dwc3", },
 207        { .compatible = "ti,am654-dwc3" },
 208        {},
 209};
 210MODULE_DEVICE_TABLE(of, kdwc3_of_match);
 211
 212static struct platform_driver kdwc3_driver = {
 213        .probe          = kdwc3_probe,
 214        .remove         = kdwc3_remove,
 215        .driver         = {
 216                .name   = "keystone-dwc3",
 217                .of_match_table = kdwc3_of_match,
 218        },
 219};
 220
 221module_platform_driver(kdwc3_driver);
 222
 223MODULE_ALIAS("platform:keystone-dwc3");
 224MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
 225MODULE_LICENSE("GPL v2");
 226MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");
 227