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 <[email protected]>
   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         struct resource         *res;
  85         int                     error, irq;
  86
  87         kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
  88         if (!kdwc)
  89                 return -ENOMEM;
  90
  91         platform_set_drvdata(pdev, kdwc);
  92
  93         kdwc->dev = dev;
  94
  95         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  96         kdwc->usbss = devm_ioremap_resource(dev, res);
  97         if (IS_ERR(kdwc->usbss))
  98                 return PTR_ERR(kdwc->usbss);
  99
 100         pm_runtime_enable(kdwc->dev);
 101
 102         error = pm_runtime_get_sync(kdwc->dev);
 103         if (error < 0) {
 104                 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
 105                         error);
 106                 goto err_irq;
 107         }
 108
 109         /* IRQ processing not required currently for AM65 */
 110         if (of_device_is_compatible(node, "ti,am654-dwc3"))
 111                 goto skip_irq;
 112
 113         irq = platform_get_irq(pdev, 0);
 114         if (irq < 0) {
 115                 dev_err(&pdev->dev, "missing irq\n");
 116                 error = irq;
 117                 goto err_irq;
 118         }
 119
 120         error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
 121                         dev_name(dev), kdwc);
 122         if (error) {
 123                 dev_err(dev, "failed to request IRQ #%d --> %d\n",
 124                                 irq, error);
 125                 goto err_irq;
 126         }
 127
 128         kdwc3_enable_irqs(kdwc);
 129
 130 skip_irq:
 131         error = of_platform_populate(node, NULL, NULL, dev);
 132         if (error) {
 133                 dev_err(&pdev->dev, "failed to create dwc3 core\n");
 134                 goto err_core;
 135         }
 136
 137         return 0;
 138
 139 err_core:
 140         kdwc3_disable_irqs(kdwc);
 141 err_irq:
 142         pm_runtime_put_sync(kdwc->dev);
 143         pm_runtime_disable(kdwc->dev);
 144
 145         return error;
 146 }
 147
 148 static int kdwc3_remove_core(struct device *dev, void *c)
 149 {
 150         struct platform_device *pdev = to_platform_device(dev);
 151
 152         platform_device_unregister(pdev);
 153
 154         return 0;
 155 }
 156
 157 static int kdwc3_remove(struct platform_device *pdev)
 158 {
 159         struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
 160         struct device_node *node = pdev->dev.of_node;
 161
 162         if (!of_device_is_compatible(node, "ti,am654-dwc3"))
 163                 kdwc3_disable_irqs(kdwc);
 164
 165         device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
 166         pm_runtime_put_sync(kdwc->dev);
 167         pm_runtime_disable(kdwc->dev);
 168
 169         platform_set_drvdata(pdev, NULL);
 170
 171         return 0;
 172 }
 173
 174 static const struct of_device_id kdwc3_of_match[] = {
 175         { .compatible = "ti,keystone-dwc3", },
 176         { .compatible = "ti,am654-dwc3" },
 177         {},
 178 };
 179 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
 180
 181 static struct platform_driver kdwc3_driver = {
 182         .probe          = kdwc3_probe,
 183         .remove         = kdwc3_remove,
 184         .driver         = {
 185                 .name   = "keystone-dwc3",
 186                 .of_match_table = kdwc3_of_match,
 187         },
 188 };
 189
 190 module_platform_driver(kdwc3_driver);
 191
 192 MODULE_ALIAS("platform:keystone-dwc3");
 193 MODULE_AUTHOR("WingMan Kwok <[email protected]>");
 194 MODULE_LICENSE("GPL v2");
 195 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");