drivers/usb/dwc3/dwc3-keystone.c

   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
  35 struct dwc3_keystone {
  36         struct device                   *dev;
  37         void __iomem                    *usbss;
  38         struct phy                      *usb3_phy;
  39 };
  40
  41 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
  42 {
  43         return readl(base + offset);
  44 }
  45
  46 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
  47 {
  48         writel(value, base + offset);
  49 }
  50
  51 static 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
  60 static 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
  69 static 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
  81 static 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                 error = PTR_ERR(kdwc->usb3_phy);
 104                 if (error != -EPROBE_DEFER)
 105                         dev_err(dev, "couldn't get usb3 phy: %d\n", error);
 106
 107                 return error;
 108         }
 109
 110         phy_pm_runtime_get_sync(kdwc->usb3_phy);
 111
 112         error = phy_reset(kdwc->usb3_phy);
 113         if (error < 0) {
 114                 dev_err(dev, "usb3 phy reset failed: %d\n", error);
 115                 return error;
 116         }
 117
 118         error = phy_init(kdwc->usb3_phy);
 119         if (error < 0) {
 120                 dev_err(dev, "usb3 phy init failed: %d\n", error);
 121                 return error;
 122         }
 123
 124         error = phy_power_on(kdwc->usb3_phy);
 125         if (error < 0) {
 126                 dev_err(dev, "usb3 phy power on failed: %d\n", error);
 127                 phy_exit(kdwc->usb3_phy);
 128                 return error;
 129         }
 130
 131         pm_runtime_enable(kdwc->dev);
 132         error = pm_runtime_get_sync(kdwc->dev);
 133         if (error < 0) {
 134                 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
 135                         error);
 136                 goto err_irq;
 137         }
 138
 139         /* IRQ processing not required currently for AM65 */
 140         if (of_device_is_compatible(node, "ti,am654-dwc3"))
 141                 goto skip_irq;
 142
 143         irq = platform_get_irq(pdev, 0);
 144         if (irq < 0) {
 145                 error = irq;
 146                 goto err_irq;
 147         }
 148
 149         error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
 150                         dev_name(dev), kdwc);
 151         if (error) {
 152                 dev_err(dev, "failed to request IRQ #%d --> %d\n",
 153                                 irq, error);
 154                 goto err_irq;
 155         }
 156
 157         kdwc3_enable_irqs(kdwc);
 158
 159 skip_irq:
 160         error = of_platform_populate(node, NULL, NULL, dev);
 161         if (error) {
 162                 dev_err(&pdev->dev, "failed to create dwc3 core\n");
 163                 goto err_core;
 164         }
 165
 166         return 0;
 167
 168 err_core:
 169         kdwc3_disable_irqs(kdwc);
 170 err_irq:
 171         pm_runtime_put_sync(kdwc->dev);
 172         pm_runtime_disable(kdwc->dev);
 173         phy_power_off(kdwc->usb3_phy);
 174         phy_exit(kdwc->usb3_phy);
 175         phy_pm_runtime_put_sync(kdwc->usb3_phy);
 176
 177         return error;
 178 }
 179
 180 static int kdwc3_remove_core(struct device *dev, void *c)
 181 {
 182         struct platform_device *pdev = to_platform_device(dev);
 183
 184         platform_device_unregister(pdev);
 185
 186         return 0;
 187 }
 188
 189 static int kdwc3_remove(struct platform_device *pdev)
 190 {
 191         struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
 192         struct device_node *node = pdev->dev.of_node;
 193
 194         if (!of_device_is_compatible(node, "ti,am654-dwc3"))
 195                 kdwc3_disable_irqs(kdwc);
 196
 197         device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
 198         pm_runtime_put_sync(kdwc->dev);
 199         pm_runtime_disable(kdwc->dev);
 200
 201         phy_power_off(kdwc->usb3_phy);
 202         phy_exit(kdwc->usb3_phy);
 203         phy_pm_runtime_put_sync(kdwc->usb3_phy);
 204
 205         platform_set_drvdata(pdev, NULL);
 206
 207         return 0;
 208 }
 209
 210 static const struct of_device_id kdwc3_of_match[] = {
 211         { .compatible = "ti,keystone-dwc3", },
 212         { .compatible = "ti,am654-dwc3" },
 213         {},
 214 };
 215 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
 216
 217 static struct platform_driver kdwc3_driver = {
 218         .probe          = kdwc3_probe,
 219         .remove         = kdwc3_remove,
 220         .driver         = {
 221                 .name   = "keystone-dwc3",
 222                 .of_match_table = kdwc3_of_match,
 223         },
 224 };
 225
 226 module_platform_driver(kdwc3_driver);
 227
 228 MODULE_ALIAS("platform:keystone-dwc3");
 229 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
 230 MODULE_LICENSE("GPL v2");
 231 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");