/*
* USB cluster support for Armada 375 platform.
*
* Copyright (C) 2014 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2 or later. This program is licensed "as is"
* without any warranty of any kind, whether express or implied.
*
* Armada 375 comes with an USB2 host and device controller and an
* USB3 controller. The USB cluster control register allows to manage
* common features of both USB controllers.
*/
#include <dt-bindings/phy/phy.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#define USB2_PHY_CONFIG_DISABLE BIT(0)
struct armada375_cluster_phy {
struct phy *phy;
void __iomem *reg;
bool use_usb3;
int phy_provided;
};
static int armada375_usb_phy_init(struct phy *phy)
{
struct armada375_cluster_phy *cluster_phy;
u32 reg;
cluster_phy = phy_get_drvdata(phy);
if (!cluster_phy)
return -ENODEV;
reg = readl(cluster_phy->reg);
if (cluster_phy->use_usb3)
reg |= USB2_PHY_CONFIG_DISABLE;
else
reg &= ~USB2_PHY_CONFIG_DISABLE;
writel(reg, cluster_phy->reg);
return 0;
}
static const struct phy_ops armada375_usb_phy_ops = {
.init = armada375_usb_phy_init,
.owner = THIS_MODULE,
};
/*
* Only one controller can use this PHY. We shouldn't have the case
* when two controllers want to use this PHY. But if this case occurs
* then we provide a phy to the first one and return an error for the
* next one. This error has also to be an error returned by
* devm_phy_optional_get() so different from ENODEV for USB2. In the
* USB3 case it still optional and we use ENODEV.
*/
static struct phy *armada375_usb_phy_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct armada375_cluster_phy *cluster_phy = dev_get_drvdata(dev);
if (!cluster_phy)
return ERR_PTR(-ENODEV);
/*
* Either the phy had never been requested and then the first
* usb claiming it can get it, or it had already been
* requested in this case, we only allow to use it with the
* same configuration.
*/
if (WARN_ON((cluster_phy->phy_provided != PHY_NONE) &&
(cluster_phy->phy_provided != args->args[0]))) {
dev_err(dev, "This PHY has already been provided!\n");
dev_err(dev, "Check your device tree, only one controller can use it\n.");
if (args->args[0] == PHY_TYPE_USB2)
return ERR_PTR(-EBUSY);
else
return ERR_PTR(-ENODEV);
}
if (args->args[0] == PHY_TYPE_USB2)
cluster_phy->use_usb3 = false;
else if (args->args[0] == PHY_TYPE_USB3)
cluster_phy->use_usb3 = true;
else {
dev_err(dev, "Invalid PHY mode\n");
return ERR_PTR(-ENODEV);
}
/* Store which phy mode is used for next test */
cluster_phy->phy_provided = args->args[0];
return cluster_phy->phy;
}
static int armada375_usb_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct phy *phy;
struct phy_provider *phy_provider;
void __iomem *usb_cluster_base;
struct resource *res;
struct armada375_cluster_phy *cluster_phy;
cluster_phy = devm_kzalloc(dev, sizeof(*cluster_phy), GFP_KERNEL);
if (!cluster_phy)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
usb_cluster_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(usb_cluster_base))
return PTR_ERR(usb_cluster_base);
phy = devm_phy_create(dev, NULL, &armada375_usb_phy_ops);
if (IS_ERR(phy)) {
dev_err(dev, "failed to create PHY\n");
return PTR_ERR(phy);
}
cluster_phy->phy = phy;
cluster_phy->reg = usb_cluster_base;
dev_set_drvdata(dev, cluster_phy);
phy_set_drvdata(phy, cluster_phy);
phy_provider = devm_of_phy_provider_register(&pdev->dev,
armada375_usb_phy_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id of_usb_cluster_table[] = {
{ .compatible = "marvell,armada-375-usb-cluster", },
{ /* end of list */ },
};
MODULE_DEVICE_TABLE(of, of_usb_cluster_table);
static struct platform_driver armada375_usb_phy_driver = {
.probe = armada375_usb_phy_probe,
.driver = {
.of_match_table = of_usb_cluster_table,
.name = "armada-375-usb-cluster",
}
};
module_platform_driver(armada375_usb_phy_driver);
MODULE_DESCRIPTION("Armada 375 USB cluster driver");
MODULE_AUTHOR("Gregory CLEMENT <gregory.clement@free-electrons.com>");
MODULE_LICENSE("GPL");
