drivers/usb/gadget/udc/rzv2m_usb3drd.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Renesas RZ/V2M USB3DRD driver
   4  *
   5  * Copyright (C) 2022 Renesas Electronics Corporation
   6  */
   7
   8 #include <linux/io.h>
   9 #include <linux/of_device.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/pm_runtime.h>
  12 #include <linux/reset.h>
  13 #include <linux/usb/rzv2m_usb3drd.h>
  14
  15 #define USB_PERI_DRD_CON        0x000
  16
  17 #define USB_PERI_DRD_CON_PERI_RST       BIT(31)
  18 #define USB_PERI_DRD_CON_HOST_RST       BIT(30)
  19 #define USB_PERI_DRD_CON_PERI_CON       BIT(24)
  20
  21 static void rzv2m_usb3drd_set_bit(struct rzv2m_usb3drd *usb3, u32 bits,
  22                                   u32 offs)
  23 {
  24         u32 val = readl(usb3->reg + offs);
  25
  26         val |= bits;
  27         writel(val, usb3->reg + offs);
  28 }
  29
  30 static void rzv2m_usb3drd_clear_bit(struct rzv2m_usb3drd *usb3, u32 bits,
  31                                     u32 offs)
  32 {
  33         u32 val = readl(usb3->reg + offs);
  34
  35         val &= ~bits;
  36         writel(val, usb3->reg + offs);
  37 }
  38
  39 void rzv2m_usb3drd_reset(struct device *dev, bool host)
  40 {
  41         struct rzv2m_usb3drd *usb3 = dev_get_drvdata(dev);
  42
  43         if (host) {
  44                 rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_PERI_CON,
  45                                         USB_PERI_DRD_CON);
  46                 rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_HOST_RST,
  47                                         USB_PERI_DRD_CON);
  48                 rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_PERI_RST,
  49                                       USB_PERI_DRD_CON);
  50         } else {
  51                 rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_PERI_CON,
  52                                       USB_PERI_DRD_CON);
  53                 rzv2m_usb3drd_set_bit(usb3, USB_PERI_DRD_CON_HOST_RST,
  54                                       USB_PERI_DRD_CON);
  55                 rzv2m_usb3drd_clear_bit(usb3, USB_PERI_DRD_CON_PERI_RST,
  56                                         USB_PERI_DRD_CON);
  57         }
  58 }
  59 EXPORT_SYMBOL_GPL(rzv2m_usb3drd_reset);
  60
  61 static int rzv2m_usb3drd_remove(struct platform_device *pdev)
  62 {
  63         struct rzv2m_usb3drd *usb3 = platform_get_drvdata(pdev);
  64
  65         of_platform_depopulate(usb3->dev);
  66         pm_runtime_put(usb3->dev);
  67         pm_runtime_disable(&pdev->dev);
  68         reset_control_assert(usb3->drd_rstc);
  69
  70         return 0;
  71 }
  72
  73 static int rzv2m_usb3drd_probe(struct platform_device *pdev)
  74 {
  75         struct rzv2m_usb3drd *usb3;
  76         int ret;
  77
  78         usb3 = devm_kzalloc(&pdev->dev, sizeof(*usb3), GFP_KERNEL);
  79         if (!usb3)
  80                 return -ENOMEM;
  81
  82         usb3->dev = &pdev->dev;
  83
  84         usb3->drd_irq = platform_get_irq_byname(pdev, "drd");
  85         if (usb3->drd_irq < 0)
  86                 return usb3->drd_irq;
  87
  88         usb3->reg = devm_platform_ioremap_resource(pdev, 0);
  89         if (IS_ERR(usb3->reg))
  90                 return PTR_ERR(usb3->reg);
  91
  92         platform_set_drvdata(pdev, usb3);
  93
  94         usb3->drd_rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
  95         if (IS_ERR(usb3->drd_rstc))
  96                 return dev_err_probe(&pdev->dev, PTR_ERR(usb3->drd_rstc),
  97                                      "failed to get drd reset");
  98
  99         reset_control_deassert(usb3->drd_rstc);
 100         pm_runtime_enable(&pdev->dev);
 101         ret = pm_runtime_resume_and_get(usb3->dev);
 102         if (ret)
 103                 goto err_rst;
 104
 105         ret = of_platform_populate(usb3->dev->of_node, NULL, NULL, usb3->dev);
 106         if (ret)
 107                 goto err_pm;
 108
 109         return 0;
 110
 111 err_pm:
 112         pm_runtime_put(usb3->dev);
 113
 114 err_rst:
 115         pm_runtime_disable(&pdev->dev);
 116         reset_control_assert(usb3->drd_rstc);
 117         return ret;
 118 }
 119
 120 static const struct of_device_id rzv2m_usb3drd_of_match[] = {
 121         { .compatible = "renesas,rzv2m-usb3drd", },
 122         { /* Sentinel */ }
 123 };
 124 MODULE_DEVICE_TABLE(of, rzv2m_usb3drd_of_match);
 125
 126 static struct platform_driver rzv2m_usb3drd_driver = {
 127         .driver = {
 128                 .name = "rzv2m-usb3drd",
 129                 .of_match_table = of_match_ptr(rzv2m_usb3drd_of_match),
 130         },
 131         .probe = rzv2m_usb3drd_probe,
 132         .remove = rzv2m_usb3drd_remove,
 133 };
 134 module_platform_driver(rzv2m_usb3drd_driver);
 135
 136 MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
 137 MODULE_DESCRIPTION("Renesas RZ/V2M USB3DRD driver");
 138 MODULE_LICENSE("GPL");
 139 MODULE_ALIAS("platform:rzv2m_usb3drd");