diff options
Diffstat (limited to 'drivers/phy/phy-armada375-usb2.c')
| -rw-r--r-- | drivers/phy/phy-armada375-usb2.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/drivers/phy/phy-armada375-usb2.c b/drivers/phy/phy-armada375-usb2.c new file mode 100644 index 000000000..8ccc3952c --- /dev/null +++ b/drivers/phy/phy-armada375-usb2.c @@ -0,0 +1,159 @@ +/* + * 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 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", + .owner = THIS_MODULE, + } +}; +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"); |