LXR linux/drivers/phy/broadcom/phy-bcm-kona-usb2.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
   4 *
   5 * Copyright (C) 2013 Linaro Limited
   6 * Matt Porter <mporter@linaro.org>
   7 */
   8
   9#include <linux/clk.h>
  10#include <linux/delay.h>
  11#include <linux/err.h>
  12#include <linux/io.h>
  13#include <linux/module.h>
  14#include <linux/of.h>
  15#include <linux/phy/phy.h>
  16#include <linux/platform_device.h>
  17
  18#define OTGCTL                  (0)
  19#define OTGCTL_OTGSTAT2         BIT(31)
  20#define OTGCTL_OTGSTAT1         BIT(30)
  21#define OTGCTL_PRST_N_SW        BIT(11)
  22#define OTGCTL_HRESET_N         BIT(10)
  23#define OTGCTL_UTMI_LINE_STATE1 BIT(9)
  24#define OTGCTL_UTMI_LINE_STATE0 BIT(8)
  25
  26#define P1CTL                   (8)
  27#define P1CTL_SOFT_RESET        BIT(1)
  28#define P1CTL_NON_DRIVING       BIT(0)
  29
  30struct bcm_kona_usb {
  31        void __iomem *regs;
  32};
  33
  34static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
  35{
  36        u32 val;
  37
  38        val = readl(phy->regs + OTGCTL);
  39        if (on) {
  40                /* Configure and power PHY */
  41                val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
  42                         OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
  43                val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
  44        } else {
  45                val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
  46        }
  47        writel(val, phy->regs + OTGCTL);
  48}
  49
  50static int bcm_kona_usb_phy_init(struct phy *gphy)
  51{
  52        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
  53        u32 val;
  54
  55        /* Soft reset PHY */
  56        val = readl(phy->regs + P1CTL);
  57        val &= ~P1CTL_NON_DRIVING;
  58        val |= P1CTL_SOFT_RESET;
  59        writel(val, phy->regs + P1CTL);
  60        writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
  61        /* Reset needs to be asserted for 2ms */
  62        mdelay(2);
  63        writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
  64
  65        return 0;
  66}
  67
  68static int bcm_kona_usb_phy_power_on(struct phy *gphy)
  69{
  70        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
  71
  72        bcm_kona_usb_phy_power(phy, 1);
  73
  74        return 0;
  75}
  76
  77static int bcm_kona_usb_phy_power_off(struct phy *gphy)
  78{
  79        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
  80
  81        bcm_kona_usb_phy_power(phy, 0);
  82
  83        return 0;
  84}
  85
  86static const struct phy_ops ops = {
  87        .init           = bcm_kona_usb_phy_init,
  88        .power_on       = bcm_kona_usb_phy_power_on,
  89        .power_off      = bcm_kona_usb_phy_power_off,
  90        .owner          = THIS_MODULE,
  91};
  92
  93static int bcm_kona_usb2_probe(struct platform_device *pdev)
  94{
  95        struct device *dev = &pdev->dev;
  96        struct bcm_kona_usb *phy;
  97        struct resource *res;
  98        struct phy *gphy;
  99        struct phy_provider *phy_provider;
 100
 101        phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
 102        if (!phy)
 103                return -ENOMEM;
 104
 105        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 106        phy->regs = devm_ioremap_resource(&pdev->dev, res);
 107        if (IS_ERR(phy->regs))
 108                return PTR_ERR(phy->regs);
 109
 110        platform_set_drvdata(pdev, phy);
 111
 112        gphy = devm_phy_create(dev, NULL, &ops);
 113        if (IS_ERR(gphy))
 114                return PTR_ERR(gphy);
 115
 116        /* The Kona PHY supports an 8-bit wide UTMI interface */
 117        phy_set_bus_width(gphy, 8);
 118
 119        phy_set_drvdata(gphy, phy);
 120
 121        phy_provider = devm_of_phy_provider_register(dev,
 122                        of_phy_simple_xlate);
 123
 124        return PTR_ERR_OR_ZERO(phy_provider);
 125}
 126
 127static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
 128        { .compatible = "brcm,kona-usb2-phy" },
 129        { /* sentinel */ }
 130};
 131
 132MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
 133
 134static struct platform_driver bcm_kona_usb2_driver = {
 135        .probe          = bcm_kona_usb2_probe,
 136        .driver         = {
 137                .name   = "bcm-kona-usb2",
 138                .of_match_table = bcm_kona_usb2_dt_ids,
 139        },
 140};
 141
 142module_platform_driver(bcm_kona_usb2_driver);
 143
 144MODULE_ALIAS("platform:bcm-kona-usb2");
 145MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
 146MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
 147MODULE_LICENSE("GPL v2");
 148