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
24 struct armada375_cluster_phy {
25 struct phy *phy;
26 void __iomem *reg;
27 bool use_usb3;
28 int phy_provided;
29 };
30
armada375_usb_phy_init(struct phy * phy)31 static 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
50 static 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 */
armada375_usb_phy_xlate(struct device * dev,struct of_phandle_args * args)63 static 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
armada375_usb_phy_probe(struct platform_device * pdev)102 static 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
135 static const struct of_device_id of_usb_cluster_table[] = {
136 { .compatible = "marvell,armada-375-usb-cluster", },
137 { /* end of list */ },
138 };
139
140 static 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 };
147 builtin_platform_driver(armada375_usb_phy_driver);
148