drivers/phy/starfive/phy-jh7110-usb.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * StarFive JH7110 USB 2.0 PHY driver
   4  *
   5  * Copyright (C) 2023 Minda Chen <minda.chen@starfivetech.com>
   6  */
   7
   8 #include <linux/bits.h>
   9 #include <linux/clk.h>
  10 #include <linux/err.h>
  11 #include <linux/io.h>
  12 #include <linux/module.h>
  13 #include <linux/phy/phy.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/usb/of.h>
  16
  17 #define USB_125M_CLK_RATE               125000000
  18 #define USB_LS_KEEPALIVE_OFF            0x4
  19 #define USB_LS_KEEPALIVE_ENABLE         BIT(4)
  20
  21 struct jh7110_usb2_phy {
  22         struct phy *phy;
  23         void __iomem *regs;
  24         struct clk *usb_125m_clk;
  25         struct clk *app_125;
  26         enum usb_dr_mode dr_mode;
  27 };
  28
  29 static void jh7110_usb2_mode_set(struct jh7110_usb2_phy *phy)
  30 {
  31         unsigned int val;
  32
  33         if (phy->dr_mode != USB_DR_MODE_PERIPHERAL) {
  34                 /* Enable the LS speed keep-alive signal */
  35                 val = readl(phy->regs + USB_LS_KEEPALIVE_OFF);
  36                 val |= USB_LS_KEEPALIVE_ENABLE;
  37                 writel(val, phy->regs + USB_LS_KEEPALIVE_OFF);
  38         }
  39 }
  40
  41 static int jh7110_usb2_phy_set_mode(struct phy *_phy,
  42                                   enum phy_mode mode, int submode)
  43 {
  44         struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
  45         int new_mode;
  46
  47         switch (mode) {
  48         case PHY_MODE_USB_HOST:
  49                 new_mode = USB_DR_MODE_HOST;
  50                 break;
  51         case PHY_MODE_USB_DEVICE:
  52                 new_mode = USB_DR_MODE_PERIPHERAL;
  53                 break;
  54         case PHY_MODE_USB_OTG:
  55                 new_mode = USB_DR_MODE_OTG;
  56                 break;
  57         default:
  58                 return -EINVAL;
  59         }
  60
  61         if (new_mode != phy->dr_mode) {
  62                 dev_info(&_phy->dev, "Changing dr_mode to %d\n", new_mode);
  63                 phy->dr_mode = new_mode;
  64                 jh7110_usb2_mode_set(phy);
  65         }
  66
  67         return 0;
  68 }
  69
  70 static int jh7110_usb2_phy_init(struct phy *_phy)
  71 {
  72         struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
  73         int ret;
  74
  75         ret = clk_set_rate(phy->usb_125m_clk, USB_125M_CLK_RATE);
  76         if (ret)
  77                 return ret;
  78
  79         ret = clk_prepare_enable(phy->app_125);
  80         if (ret)
  81                 return ret;
  82
  83         return 0;
  84 }
  85
  86 static int jh7110_usb2_phy_exit(struct phy *_phy)
  87 {
  88         struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
  89
  90         clk_disable_unprepare(phy->app_125);
  91
  92         return 0;
  93 }
  94
  95 static const struct phy_ops jh7110_usb2_phy_ops = {
  96         .init           = jh7110_usb2_phy_init,
  97         .exit           = jh7110_usb2_phy_exit,
  98         .set_mode       = jh7110_usb2_phy_set_mode,
  99         .owner          = THIS_MODULE,
 100 };
 101
 102 static int jh7110_usb_phy_probe(struct platform_device *pdev)
 103 {
 104         struct jh7110_usb2_phy *phy;
 105         struct device *dev = &pdev->dev;
 106         struct phy_provider *phy_provider;
 107
 108         phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
 109         if (!phy)
 110                 return -ENOMEM;
 111
 112         phy->usb_125m_clk = devm_clk_get(dev, "125m");
 113         if (IS_ERR(phy->usb_125m_clk))
 114                 return dev_err_probe(dev, PTR_ERR(phy->usb_125m_clk),
 115                         "Failed to get 125m clock\n");
 116
 117         phy->app_125 = devm_clk_get(dev, "app_125");
 118         if (IS_ERR(phy->app_125))
 119                 return dev_err_probe(dev, PTR_ERR(phy->app_125),
 120                         "Failed to get app 125m clock\n");
 121
 122         phy->regs = devm_platform_ioremap_resource(pdev, 0);
 123         if (IS_ERR(phy->regs))
 124                 return dev_err_probe(dev, PTR_ERR(phy->regs),
 125                         "Failed to map phy base\n");
 126
 127         phy->phy = devm_phy_create(dev, NULL, &jh7110_usb2_phy_ops);
 128         if (IS_ERR(phy->phy))
 129                 return dev_err_probe(dev, PTR_ERR(phy->phy),
 130                         "Failed to create phy\n");
 131
 132         platform_set_drvdata(pdev, phy);
 133         phy_set_drvdata(phy->phy, phy);
 134         phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 135
 136         return PTR_ERR_OR_ZERO(phy_provider);
 137 }
 138
 139 static int jh7110_usb_phy_remove(struct platform_device *pdev)
 140 {
 141         struct jh7110_usb2_phy *phy = platform_get_drvdata(pdev);
 142
 143         clk_disable_unprepare(phy->app_125);
 144         platform_set_drvdata(pdev, NULL);
 145
 146         return 0;
 147 }
 148
 149 static const struct of_device_id jh7110_usb_phy_of_match[] = {
 150         { .compatible = "starfive,jh7110-usb-phy" },
 151         { /* sentinel */ },
 152 };
 153 MODULE_DEVICE_TABLE(of, jh7110_usb_phy_of_match);
 154
 155 static struct platform_driver jh7110_usb_phy_driver = {
 156         .probe  = jh7110_usb_phy_probe,
 157         .remove = jh7110_usb_phy_remove,
 158         .driver = {
 159                 .of_match_table = jh7110_usb_phy_of_match,
 160                 .name  = "jh7110-usb-phy",
 161         }
 162 };
 163 module_platform_driver(jh7110_usb_phy_driver);
 164
 165 MODULE_DESCRIPTION("StarFive JH7110 USB 2.0 PHY driver");
 166 MODULE_AUTHOR("Minda Chen <minda.chen@starfivetech.com>");
 167 MODULE_LICENSE("GPL");