drivers/usb/dwc3/dwc3-keystone.c

   1 /**
   2  * dwc3-keystone.c - Keystone Specific Glue layer
   3  *
   4  * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com
   5  *
   6  * Author: WingMan Kwok <w-kwok2@ti.com>
   7  *
   8  * This program is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2  of
  10  * the License as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/io.h>
  24 #include <linux/of_platform.h>
  25 #include <linux/pm_runtime.h>
  26
  27 /* USBSS register offsets */
  28 #define USBSS_REVISION          0x0000
  29 #define USBSS_SYSCONFIG         0x0010
  30 #define USBSS_IRQ_EOI           0x0018
  31 #define USBSS_IRQSTATUS_RAW_0   0x0020
  32 #define USBSS_IRQSTATUS_0       0x0024
  33 #define USBSS_IRQENABLE_SET_0   0x0028
  34 #define USBSS_IRQENABLE_CLR_0   0x002c
  35
  36 /* IRQ register bits */
  37 #define USBSS_IRQ_EOI_LINE(n)   BIT(n)
  38 #define USBSS_IRQ_EVENT_ST      BIT(0)
  39 #define USBSS_IRQ_COREIRQ_EN    BIT(0)
  40 #define USBSS_IRQ_COREIRQ_CLR   BIT(0)
  41
  42 struct dwc3_keystone {
  43         struct device                   *dev;
  44         void __iomem                    *usbss;
  45 };
  46
  47 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
  48 {
  49         return readl(base + offset);
  50 }
  51
  52 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
  53 {
  54         writel(value, base + offset);
  55 }
  56
  57 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
  58 {
  59         u32 val;
  60
  61         val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  62         val |= USBSS_IRQ_COREIRQ_EN;
  63         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  64 }
  65
  66 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
  67 {
  68         u32 val;
  69
  70         val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
  71         val &= ~USBSS_IRQ_COREIRQ_EN;
  72         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
  73 }
  74
  75 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
  76 {
  77         struct dwc3_keystone    *kdwc = _kdwc;
  78
  79         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
  80         kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
  81         kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
  82         kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
  83
  84         return IRQ_HANDLED;
  85 }
  86
  87 static int kdwc3_probe(struct platform_device *pdev)
  88 {
  89         struct device           *dev = &pdev->dev;
  90         struct device_node      *node = pdev->dev.of_node;
  91         struct dwc3_keystone    *kdwc;
  92         struct resource         *res;
  93         int                     error, irq;
  94
  95         kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
  96         if (!kdwc)
  97                 return -ENOMEM;
  98
  99         platform_set_drvdata(pdev, kdwc);
 100
 101         kdwc->dev = dev;
 102
 103         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 104         kdwc->usbss = devm_ioremap_resource(dev, res);
 105         if (IS_ERR(kdwc->usbss))
 106                 return PTR_ERR(kdwc->usbss);
 107
 108         pm_runtime_enable(kdwc->dev);
 109
 110         error = pm_runtime_get_sync(kdwc->dev);
 111         if (error < 0) {
 112                 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
 113                         error);
 114                 goto err_irq;
 115         }
 116
 117         irq = platform_get_irq(pdev, 0);
 118         if (irq < 0) {
 119                 dev_err(&pdev->dev, "missing irq\n");
 120                 error = irq;
 121                 goto err_irq;
 122         }
 123
 124         error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
 125                         dev_name(dev), kdwc);
 126         if (error) {
 127                 dev_err(dev, "failed to request IRQ #%d --> %d\n",
 128                                 irq, error);
 129                 goto err_irq;
 130         }
 131
 132         kdwc3_enable_irqs(kdwc);
 133
 134         error = of_platform_populate(node, NULL, NULL, dev);
 135         if (error) {
 136                 dev_err(&pdev->dev, "failed to create dwc3 core\n");
 137                 goto err_core;
 138         }
 139
 140         return 0;
 141
 142 err_core:
 143         kdwc3_disable_irqs(kdwc);
 144 err_irq:
 145         pm_runtime_put_sync(kdwc->dev);
 146         pm_runtime_disable(kdwc->dev);
 147
 148         return error;
 149 }
 150
 151 static int kdwc3_remove_core(struct device *dev, void *c)
 152 {
 153         struct platform_device *pdev = to_platform_device(dev);
 154
 155         platform_device_unregister(pdev);
 156
 157         return 0;
 158 }
 159
 160 static int kdwc3_remove(struct platform_device *pdev)
 161 {
 162         struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
 163
 164         kdwc3_disable_irqs(kdwc);
 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         {},
 177 };
 178 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
 179
 180 static struct platform_driver kdwc3_driver = {
 181         .probe          = kdwc3_probe,
 182         .remove         = kdwc3_remove,
 183         .driver         = {
 184                 .name   = "keystone-dwc3",
 185                 .of_match_table = kdwc3_of_match,
 186         },
 187 };
 188
 189 module_platform_driver(kdwc3_driver);
 190
 191 MODULE_ALIAS("platform:keystone-dwc3");
 192 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
 193 MODULE_LICENSE("GPL v2");
 194 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");