LXR linux/drivers/phy/marvell/phy-armada375-usb2.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * USB cluster support for Armada 375 platform.
   4 *
   5 * Copyright (C) 2014 Marvell
   6 *
   7 * Gregory CLEMENT <gregory.clement@free-electrons.com>
   8 *
   9 * Armada 375 comes with an USB2 host and device controller and an
  10 * USB3 controller. The USB cluster control register allows to manage
  11 * common features of both USB controllers.
  12 */
  13
  14#include <dt-bindings/phy/phy.h>
  15#include <linux/init.h>
  16#include <linux/io.h>
  17#include <linux/kernel.h>
  18#include <linux/of_address.h>
  19#include <linux/phy/phy.h>
  20#include <linux/platform_device.h>
  21
  22#define USB2_PHY_CONFIG_DISABLE BIT(0)
  23
  24struct armada375_cluster_phy {
  25        struct phy *phy;
  26        void __iomem *reg;
  27        bool use_usb3;
  28        int phy_provided;
  29};
  30
  31static int armada375_usb_phy_init(struct phy *phy)
  32{
  33        struct armada375_cluster_phy *cluster_phy;
  34        u32 reg;
  35
  36        cluster_phy = phy_get_drvdata(phy);
  37        if (!cluster_phy)
  38                return -ENODEV;
  39
  40        reg = readl(cluster_phy->reg);
  41        if (cluster_phy->use_usb3)
  42                reg |= USB2_PHY_CONFIG_DISABLE;
  43        else
  44                reg &= ~USB2_PHY_CONFIG_DISABLE;
  45        writel(reg, cluster_phy->reg);
  46
  47        return 0;
  48}
  49
  50static const struct phy_ops armada375_usb_phy_ops = {
  51        .init = armada375_usb_phy_init,
  52        .owner = THIS_MODULE,
  53};
  54
  55/*
  56 * Only one controller can use this PHY. We shouldn't have the case
  57 * when two controllers want to use this PHY. But if this case occurs
  58 * then we provide a phy to the first one and return an error for the
  59 * next one. This error has also to be an error returned by
  60 * devm_phy_optional_get() so different from ENODEV for USB2. In the
  61 * USB3 case it still optional and we use ENODEV.
  62 */
  63static struct phy *armada375_usb_phy_xlate(struct device *dev,
  64                                        struct of_phandle_args *args)
  65{
  66        struct armada375_cluster_phy *cluster_phy = dev_get_drvdata(dev);
  67
  68        if (!cluster_phy)
  69                return  ERR_PTR(-ENODEV);
  70
  71        /*
  72         * Either the phy had never been requested and then the first
  73         * usb claiming it can get it, or it had already been
  74         * requested in this case, we only allow to use it with the
  75         * same configuration.
  76         */
  77        if (WARN_ON((cluster_phy->phy_provided != PHY_NONE) &&
  78                        (cluster_phy->phy_provided != args->args[0]))) {
  79                dev_err(dev, "This PHY has already been provided!\n");
  80                dev_err(dev, "Check your device tree, only one controller can use it\n.");
  81                if (args->args[0] == PHY_TYPE_USB2)
  82                        return ERR_PTR(-EBUSY);
  83                else
  84                        return ERR_PTR(-ENODEV);
  85        }
  86
  87        if (args->args[0] == PHY_TYPE_USB2)
  88                cluster_phy->use_usb3 = false;
  89        else if (args->args[0] == PHY_TYPE_USB3)
  90                cluster_phy->use_usb3 = true;
  91        else {
  92                dev_err(dev, "Invalid PHY mode\n");
  93                return ERR_PTR(-ENODEV);
  94        }
  95
  96        /* Store which phy mode is used for next test */
  97        cluster_phy->phy_provided = args->args[0];
  98
  99        return cluster_phy->phy;
 100}
 101
 102static int armada375_usb_phy_probe(struct platform_device *pdev)
 103{
 104        struct device *dev = &pdev->dev;
 105        struct phy *phy;
 106        struct phy_provider *phy_provider;
 107        void __iomem *usb_cluster_base;
 108        struct resource *res;
 109        struct armada375_cluster_phy *cluster_phy;
 110
 111        cluster_phy = devm_kzalloc(dev, sizeof(*cluster_phy), GFP_KERNEL);
 112        if (!cluster_phy)
 113                return  -ENOMEM;
 114
 115        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 116        usb_cluster_base = devm_ioremap_resource(&pdev->dev, res);
 117        if (IS_ERR(usb_cluster_base))
 118                return PTR_ERR(usb_cluster_base);
 119
 120        phy = devm_phy_create(dev, NULL, &armada375_usb_phy_ops);
 121        if (IS_ERR(phy)) {
 122                dev_err(dev, "failed to create PHY\n");
 123                return PTR_ERR(phy);
 124        }
 125
 126        cluster_phy->phy = phy;
 127        cluster_phy->reg = usb_cluster_base;
 128
 129        dev_set_drvdata(dev, cluster_phy);
 130        phy_set_drvdata(phy, cluster_phy);
 131
 132        phy_provider = devm_of_phy_provider_register(&pdev->dev,
 133                                                     armada375_usb_phy_xlate);
 134        return PTR_ERR_OR_ZERO(phy_provider);
 135}
 136
 137static const struct of_device_id of_usb_cluster_table[] = {
 138        { .compatible = "marvell,armada-375-usb-cluster", },
 139        { /* end of list */ },
 140};
 141
 142static struct platform_driver armada375_usb_phy_driver = {
 143        .probe  = armada375_usb_phy_probe,
 144        .driver = {
 145                .of_match_table = of_usb_cluster_table,
 146                .name  = "armada-375-usb-cluster",
 147        }
 148};
 149builtin_platform_driver(armada375_usb_phy_driver);
 150