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 <log.h>
  10 #include <dm/device.h>
  11 #include <generic-phy.h>
  12 #include <asm/io.h>
  13 #include <asm/arch/psc_defs.h>
  14 #include <linux/delay.h>
  15
  16 /* USB PHY control register offsets */
  17 #define USB_PHY_CTL_UTMI                0x0000
  18 #define USB_PHY_CTL_PIPE                0x0004
  19 #define USB_PHY_CTL_PARAM_1             0x0008
  20 #define USB_PHY_CTL_PARAM_2             0x000c
  21 #define USB_PHY_CTL_CLOCK               0x0010
  22 #define USB_PHY_CTL_PLL                 0x0014
  23
  24 #define PHY_OTG_VBUSVLDECTSEL           BIT(16)
  25 #define PHY_REF_SSP_EN                  BIT(29)
  26
  27 struct keystone_usb_phy {
  28         u32 psc_domain;
  29         void __iomem *reg;
  30 };
  31
  32 static int keystone_usb_init(struct phy *phy)
  33 {
  34         u32 val;
  35         int rc;
  36         struct udevice *dev = phy->dev;
  37         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  38
  39         /* Release USB from reset */
  40         rc = psc_enable_module(keystone->psc_domain);
  41         if (rc) {
  42                 debug("Cannot enable USB module");
  43                 return -rc;
  44         }
  45         mdelay(10);
  46
  47         /*
  48          * VBUSVLDEXTSEL has a default value of 1 in BootCfg but shouldn't.
  49          * It should always be cleared because our USB PHY has an onchip VBUS
  50          * analog comparator.
  51          */
  52         val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
  53         /* quit selecting the vbusvldextsel by default! */
  54         val &= ~PHY_OTG_VBUSVLDECTSEL;
  55         writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
  56
  57         return 0;
  58 }
  59
  60 static int keystone_usb_power_on(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_power_off(struct phy *phy)
  74 {
  75         u32 val;
  76         struct udevice *dev = phy->dev;
  77         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  78
  79         val = readl(keystone->reg + USB_PHY_CTL_CLOCK);
  80         val &= ~PHY_REF_SSP_EN;
  81         writel(val, keystone->reg + USB_PHY_CTL_CLOCK);
  82
  83         return 0;
  84 }
  85
  86 static int keystone_usb_exit(struct phy *phy)
  87 {
  88         struct udevice *dev = phy->dev;
  89         struct keystone_usb_phy *keystone = dev_get_priv(dev);
  90
  91         if (psc_disable_module(keystone->psc_domain))
  92                 debug("failed to disable USB module!\n");
  93
  94         return 0;
  95 }
  96
  97 static int keystone_usb_phy_probe(struct udevice *dev)
  98 {
  99         int rc;
 100         struct keystone_usb_phy *keystone = dev_get_priv(dev);
 101
 102         rc = dev_read_u32(dev, "psc-domain", &keystone->psc_domain);
 103         if (rc)
 104                 return rc;
 105
 106         keystone->reg = dev_remap_addr_index(dev, 0);
 107         if (!keystone->reg) {
 108                 pr_err("unable to remap usb phy\n");
 109                 return -EINVAL;
 110         }
 111         return 0;
 112 }
 113
 114 static const struct udevice_id keystone_usb_phy_ids[] = {
 115         { .compatible = "ti,keystone-usbphy" },
 116         { }
 117 };
 118
 119 static struct phy_ops keystone_usb_phy_ops = {
 120         .init = keystone_usb_init,
 121         .power_on = keystone_usb_power_on,
 122         .power_off = keystone_usb_power_off,
 123         .exit = keystone_usb_exit,
 124 };
 125
 126 U_BOOT_DRIVER(keystone_usb_phy) = {
 127         .name   = "keystone_usb_phy",
 128         .id     = UCLASS_PHY,
 129         .of_match = keystone_usb_phy_ids,
 130         .ops = &keystone_usb_phy_ops,
 131         .probe = keystone_usb_phy_probe,
 132         .priv_auto_alloc_size = sizeof(struct keystone_usb_phy),
 133 };