drivers/phy/keystone-usb-phy.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
   4  * Written by Jean-Jacques Hiblot  <jjhiblot@ti.com>
   5  */
   6
   7 #include <common.h>
   8 #include <dm.h>
   9 #include <dm/device.h>
  10 #include <generic-phy.h>
  11 #include <asm/io.h>
  12
  13 /* USB PHY control register offsets */
  14 #define USB_PHY_CTL_UTMI                0x0000
  15 #define USB_PHY_CTL_PIPE                0x0004
  16 #define USB_PHY_CTL_PARAM_1             0x0008
  17 #define USB_PHY_CTL_PARAM_2             0x000c
  18 #define USB_PHY_CTL_CLOCK               0x0010
  19 #define USB_PHY_CTL_PLL                 0x0014
  20
  21 #define PHY_OTG_VBUSVLDECTSEL           BIT(16)
  22 #define PHY_REF_SSP_EN                  BIT(29)
  23
  24 struct keystone_usb_phy {
  25         void __iomem *reg;
  26 };
  27
  28 static int keystone_usb_init(struct phy *phy)
  29 {
  30         u32 val;
  31         struct udevice *dev = phy->dev;
  32         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  33
  34         /*
  35          * VBUSVLDEXTSEL has a default value of 1 in BootCfg but shouldn't.
  36          * It should always be cleared because our USB PHY has an onchip VBUS
  37          * analog comparator.
  38          */
  39         val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
  40         /* quit selecting the vbusvldextsel by default! */
  41         val &= ~PHY_OTG_VBUSVLDECTSEL;
  42         writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
  43
  44         return 0;
  45 }
  46
  47 static int keystone_usb_power_on(struct phy *phy)
  48 {
  49         u32 val;
  50         struct udevice *dev = phy->dev;
  51         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  52
  53         val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
  54         val |= PHY_REF_SSP_EN;
  55         writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
  56
  57         return 0;
  58 }
  59
  60 static int keystone_usb_power_off(struct phy *phy)
  61 {
  62         u32 val;
  63         struct udevice *dev = phy->dev;
  64         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  65
  66         val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
  67         val &= ~PHY_REF_SSP_EN;
  68         writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
  69
  70         return 0;
  71 }
  72
  73 static int keystone_usb_exit(struct phy *phy)
  74 {
  75         return 0;
  76 }
  77
  78 static int keystone_usb_phy_probe(struct udevice *dev)
  79 {
  80         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  81
  82         keystone->reg = dev_remap_addr_index(dev, 0);
  83         if (!keystone->reg) {
  84                 pr_err("unable to remap usb phy\n");
  85                 return -EINVAL;
  86         }
  87         return 0;
  88 }
  89
  90 static const struct udevice_id keystone_usb_phy_ids[] = {
  91         { .compatible = "ti,keystone-usbphy" },
  92         { }
  93 };
  94
  95 static struct phy_ops keystone_usb_phy_ops = {
  96         .init = keystone_usb_init,
  97         .power_on = keystone_usb_power_on,
  98         .power_off = keystone_usb_power_off,
  99         .exit = keystone_usb_exit,
 100 };
 101
 102 U_BOOT_DRIVER(keystone_usb_phy) = {
 103         .name   = "keystone_usb_phy",
 104         .id     = UCLASS_PHY,
 105         .of_match = keystone_usb_phy_ids,
 106         .ops = &keystone_usb_phy_ops,
 107         .probe = keystone_usb_phy_probe,
 108         .priv_auto_alloc_size = sizeof(struct keystone_usb_phy),
 109 };