drivers/usb/otg/mxs-phy.c

   1 /*
   2  * Copyright 2012 Freescale Semiconductor, Inc.
   3  * Copyright (C) 2012 Marek Vasut <marex@denx.de>
   4  * on behalf of DENX Software Engineering GmbH
   5  *
   6  * The code contained herein is licensed under the GNU General Public
   7  * License. You may obtain a copy of the GNU General Public License
   8  * Version 2 or later at the following locations:
   9  *
  10  * http://www.opensource.org/licenses/gpl-license.html
  11  * http://www.gnu.org/copyleft/gpl.html
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/clk.h>
  18 #include <linux/usb/otg.h>
  19 #include <linux/stmp_device.h>
  20 #include <linux/delay.h>
  21 #include <linux/err.h>
  22 #include <linux/io.h>
  23
  24 #define DRIVER_NAME "mxs_phy"
  25
  26 #define HW_USBPHY_PWD                           0x00
  27 #define HW_USBPHY_CTRL                          0x30
  28 #define HW_USBPHY_CTRL_SET                      0x34
  29 #define HW_USBPHY_CTRL_CLR                      0x38
  30
  31 #define BM_USBPHY_CTRL_SFTRST                   BIT(31)
  32 #define BM_USBPHY_CTRL_CLKGATE                  BIT(30)
  33 #define BM_USBPHY_CTRL_ENUTMILEVEL3             BIT(15)
  34 #define BM_USBPHY_CTRL_ENUTMILEVEL2             BIT(14)
  35 #define BM_USBPHY_CTRL_ENHOSTDISCONDETECT       BIT(1)
  36
  37 struct mxs_phy {
  38         struct usb_phy phy;
  39         struct clk *clk;
  40 };
  41
  42 #define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
  43
  44 static void mxs_phy_hw_init(struct mxs_phy *mxs_phy)
  45 {
  46         void __iomem *base = mxs_phy->phy.io_priv;
  47
  48         stmp_reset_block(base + HW_USBPHY_CTRL);
  49
  50         /* Power up the PHY */
  51         writel_relaxed(0, base + HW_USBPHY_PWD);
  52
  53         /* enable FS/LS device */
  54         writel_relaxed(BM_USBPHY_CTRL_ENUTMILEVEL2 |
  55                         BM_USBPHY_CTRL_ENUTMILEVEL3,
  56                         base + HW_USBPHY_CTRL_SET);
  57 }
  58
  59 static int mxs_phy_init(struct usb_phy *phy)
  60 {
  61         struct mxs_phy *mxs_phy = to_mxs_phy(phy);
  62
  63         clk_prepare_enable(mxs_phy->clk);
  64         mxs_phy_hw_init(mxs_phy);
  65
  66         return 0;
  67 }
  68
  69 static void mxs_phy_shutdown(struct usb_phy *phy)
  70 {
  71         struct mxs_phy *mxs_phy = to_mxs_phy(phy);
  72
  73         writel_relaxed(BM_USBPHY_CTRL_CLKGATE,
  74                         phy->io_priv + HW_USBPHY_CTRL_SET);
  75
  76         clk_disable_unprepare(mxs_phy->clk);
  77 }
  78
  79 static int mxs_phy_on_connect(struct usb_phy *phy,
  80                 enum usb_device_speed speed)
  81 {
  82         dev_dbg(phy->dev, "%s speed device has connected\n",
  83                 (speed == USB_SPEED_HIGH) ? "high" : "non-high");
  84
  85         if (speed == USB_SPEED_HIGH)
  86                 writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
  87                                 phy->io_priv + HW_USBPHY_CTRL_SET);
  88
  89         return 0;
  90 }
  91
  92 static int mxs_phy_on_disconnect(struct usb_phy *phy,
  93                 enum usb_device_speed speed)
  94 {
  95         dev_dbg(phy->dev, "%s speed device has disconnected\n",
  96                 (speed == USB_SPEED_HIGH) ? "high" : "non-high");
  97
  98         if (speed == USB_SPEED_HIGH)
  99                 writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
 100                                 phy->io_priv + HW_USBPHY_CTRL_CLR);
 101
 102         return 0;
 103 }
 104
 105 static int mxs_phy_probe(struct platform_device *pdev)
 106 {
 107         struct resource *res;
 108         void __iomem *base;
 109         struct clk *clk;
 110         struct mxs_phy *mxs_phy;
 111
 112         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 113         if (!res) {
 114                 dev_err(&pdev->dev, "can't get device resources\n");
 115                 return -ENOENT;
 116         }
 117
 118         base = devm_request_and_ioremap(&pdev->dev, res);
 119         if (!base)
 120                 return -EBUSY;
 121
 122         clk = devm_clk_get(&pdev->dev, NULL);
 123         if (IS_ERR(clk)) {
 124                 dev_err(&pdev->dev,
 125                         "can't get the clock, err=%ld", PTR_ERR(clk));
 126                 return PTR_ERR(clk);
 127         }
 128
 129         mxs_phy = devm_kzalloc(&pdev->dev, sizeof(*mxs_phy), GFP_KERNEL);
 130         if (!mxs_phy) {
 131                 dev_err(&pdev->dev, "Failed to allocate USB PHY structure!\n");
 132                 return -ENOMEM;
 133         }
 134
 135         mxs_phy->phy.io_priv            = base;
 136         mxs_phy->phy.dev                = &pdev->dev;
 137         mxs_phy->phy.label              = DRIVER_NAME;
 138         mxs_phy->phy.init               = mxs_phy_init;
 139         mxs_phy->phy.shutdown           = mxs_phy_shutdown;
 140         mxs_phy->phy.notify_connect     = mxs_phy_on_connect;
 141         mxs_phy->phy.notify_disconnect  = mxs_phy_on_disconnect;
 142
 143         ATOMIC_INIT_NOTIFIER_HEAD(&mxs_phy->phy.notifier);
 144
 145         mxs_phy->clk = clk;
 146
 147         platform_set_drvdata(pdev, &mxs_phy->phy);
 148
 149         return 0;
 150 }
 151
 152 static int mxs_phy_remove(struct platform_device *pdev)
 153 {
 154         platform_set_drvdata(pdev, NULL);
 155
 156         return 0;
 157 }
 158
 159 static const struct of_device_id mxs_phy_dt_ids[] = {
 160         { .compatible = "fsl,imx23-usbphy", },
 161         { /* sentinel */ }
 162 };
 163 MODULE_DEVICE_TABLE(of, mxs_phy_dt_ids);
 164
 165 static struct platform_driver mxs_phy_driver = {
 166         .probe = mxs_phy_probe,
 167         .remove = mxs_phy_remove,
 168         .driver = {
 169                 .name = DRIVER_NAME,
 170                 .owner  = THIS_MODULE,
 171                 .of_match_table = mxs_phy_dt_ids,
 172          },
 173 };
 174
 175 static int __init mxs_phy_module_init(void)
 176 {
 177         return platform_driver_register(&mxs_phy_driver);
 178 }
 179 postcore_initcall(mxs_phy_module_init);
 180
 181 static void __exit mxs_phy_module_exit(void)
 182 {
 183         platform_driver_unregister(&mxs_phy_driver);
 184 }
 185 module_exit(mxs_phy_module_exit);
 186
 187 MODULE_ALIAS("platform:mxs-usb-phy");
 188 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
 189 MODULE_AUTHOR("Richard Zhao <richard.zhao@freescale.com>");
 190 MODULE_DESCRIPTION("Freescale MXS USB PHY driver");
 191 MODULE_LICENSE("GPL");