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 - http://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/pm_runtime.h>
  18
  19 /* USBSS register offsets */
  20 #define USBSS_REVISION          0x0000
  21 #define USBSS_SYSCONFIG         0x0010
  22 #define USBSS_IRQ_EOI           0x0018
  23 #define USBSS_IRQSTATUS_RAW_0   0x0020
  24 #define USBSS_IRQSTATUS_0       0x0024
  25 #define USBSS_IRQENABLE_SET_0   0x0028
  26 #define USBSS_IRQENABLE_CLR_0   0x002c
  27
  28 /* IRQ register bits */
  29 #define USBSS_IRQ_EOI_LINE(n)   BIT(n)
  30 #define USBSS_IRQ_EVENT_ST      BIT(0)
  31 #define USBSS_IRQ_COREIRQ_EN    BIT(0)
  32 #define USBSS_IRQ_COREIRQ_CLR   BIT(0)
  33
  34 struct dwc3_keystone {
  35         struct device                   *dev;
  36         void __iomem                    *usbss;
  37 };
  38
  39 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
  40 {
  41         return readl(base + offset);
  42 }
  43
  44 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
  45 {
  46         writel(value, base + offset);
  47 }
  48
  49 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
  50 {
  51         u32 val;
  52
  53         val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  54         val |= USBSS_IRQ_COREIRQ_EN;
  55         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  56 }
  57
  58 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
  59 {
  60         u32 val;
  61
  62         val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  63         val &= ~USBSS_IRQ_COREIRQ_EN;
  64         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  65 }
  66
  67 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
  68 {
  69         struct dwc3_keystone    *kdwc = _kdwc;
  70
  71         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
  72         kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
  73         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
  74         kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
  75
  76         return IRQ_HANDLED;
  77 }
  78
  79 static int kdwc3_probe(struct platform_device *pdev)
  80 {
  81         struct device           *dev = &pdev->dev;
  82         struct device_node      *node = pdev->dev.of_node;
  83         struct dwc3_keystone    *kdwc;
  84         int                     error, irq;
  85
  86         kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
  87         if (!kdwc)
  88                 return -ENOMEM;
  89
  90         platform_set_drvdata(pdev, kdwc);
  91
  92         kdwc->dev = dev;
  93
  94         kdwc->usbss = devm_platform_ioremap_resource(pdev, 0);
  95         if (IS_ERR(kdwc->usbss))
  96                 return PTR_ERR(kdwc->usbss);
  97
  98         pm_runtime_enable(kdwc->dev);
  99
 100         error = pm_runtime_get_sync(kdwc->dev);
 101         if (error < 0) {
 102                 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
 103                         error);
 104                 goto err_irq;
 105         }
 106
 107         /* IRQ processing not required currently for AM65 */
 108         if (of_device_is_compatible(node, "ti,am654-dwc3"))
 109                 goto skip_irq;
 110
 111         irq = platform_get_irq(pdev, 0);
 112         if (irq < 0) {
 113                 error = irq;
 114                 goto err_irq;
 115         }
 116
 117         error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
 118                         dev_name(dev), kdwc);
 119         if (error) {
 120                 dev_err(dev, "failed to request IRQ #%d --> %d\n",
 121                                 irq, error);
 122                 goto err_irq;
 123         }
 124
 125         kdwc3_enable_irqs(kdwc);
 126
 127 skip_irq:
 128         error = of_platform_populate(node, NULL, NULL, dev);
 129         if (error) {
 130                 dev_err(&pdev->dev, "failed to create dwc3 core\n");
 131                 goto err_core;
 132         }
 133
 134         return 0;
 135
 136 err_core:
 137         kdwc3_disable_irqs(kdwc);
 138 err_irq:
 139         pm_runtime_put_sync(kdwc->dev);
 140         pm_runtime_disable(kdwc->dev);
 141
 142         return error;
 143 }
 144
 145 static int kdwc3_remove_core(struct device *dev, void *c)
 146 {
 147         struct platform_device *pdev = to_platform_device(dev);
 148
 149         platform_device_unregister(pdev);
 150
 151         return 0;
 152 }
 153
 154 static int kdwc3_remove(struct platform_device *pdev)
 155 {
 156         struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
 157         struct device_node *node = pdev->dev.of_node;
 158
 159         if (!of_device_is_compatible(node, "ti,am654-dwc3"))
 160                 kdwc3_disable_irqs(kdwc);
 161
 162         device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
 163         pm_runtime_put_sync(kdwc->dev);
 164         pm_runtime_disable(kdwc->dev);
 165
 166         platform_set_drvdata(pdev, NULL);
 167
 168         return 0;
 169 }
 170
 171 static const struct of_device_id kdwc3_of_match[] = {
 172         { .compatible = "ti,keystone-dwc3", },
 173         { .compatible = "ti,am654-dwc3" },
 174         {},
 175 };
 176 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
 177
 178 static struct platform_driver kdwc3_driver = {
 179         .probe          = kdwc3_probe,
 180         .remove         = kdwc3_remove,
 181         .driver         = {
 182                 .name   = "keystone-dwc3",
 183                 .of_match_table = kdwc3_of_match,
 184         },
 185 };
 186
 187 module_platform_driver(kdwc3_driver);
 188
 189 MODULE_ALIAS("platform:keystone-dwc3");
 190 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
 191 MODULE_LICENSE("GPL v2");
 192 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");