cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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phy-armada375-usb2.c (3983B)

      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 armada375_cluster_phy *cluster_phy;
    109
    110	cluster_phy = devm_kzalloc(dev, sizeof(*cluster_phy), GFP_KERNEL);
    111	if (!cluster_phy)
    112		return  -ENOMEM;
    113
    114	usb_cluster_base = devm_platform_ioremap_resource(pdev, 0);
    115	if (IS_ERR(usb_cluster_base))
    116		return PTR_ERR(usb_cluster_base);
    117
    118	phy = devm_phy_create(dev, NULL, &armada375_usb_phy_ops);
    119	if (IS_ERR(phy)) {
    120		dev_err(dev, "failed to create PHY\n");
    121		return PTR_ERR(phy);
    122	}
    123
    124	cluster_phy->phy = phy;
    125	cluster_phy->reg = usb_cluster_base;
    126
    127	dev_set_drvdata(dev, cluster_phy);
    128	phy_set_drvdata(phy, cluster_phy);
    129
    130	phy_provider = devm_of_phy_provider_register(&pdev->dev,
    131						     armada375_usb_phy_xlate);
    132	return PTR_ERR_OR_ZERO(phy_provider);
    133}
    134
    135static const struct of_device_id of_usb_cluster_table[] = {
    136	{ .compatible = "marvell,armada-375-usb-cluster", },
    137	{ /* end of list */ },
    138};
    139
    140static struct platform_driver armada375_usb_phy_driver = {
    141	.probe	= armada375_usb_phy_probe,
    142	.driver = {
    143		.of_match_table	= of_usb_cluster_table,
    144		.name  = "armada-375-usb-cluster",
    145	}
    146};
    147builtin_platform_driver(armada375_usb_phy_driver);