1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/module.h>
3 #include <linux/platform_device.h>
4 #include <linux/err.h>
5 #include <linux/of.h>
6 #include <linux/io.h>
7 #include <linux/delay.h>
8 #include <linux/usb/otg.h>
9 #include "phy-am335x-control.h"
10 
11 struct am335x_control_usb {
12 	struct device *dev;
13 	void __iomem *phy_reg;
14 	void __iomem *wkup;
15 	spinlock_t lock;
16 	struct phy_control phy_ctrl;
17 };
18 
19 #define AM335X_USB0_CTRL		0x0
20 #define AM335X_USB1_CTRL		0x8
21 #define AM335x_USB_WKUP			0x0
22 
23 #define USBPHY_CM_PWRDN		(1 << 0)
24 #define USBPHY_OTG_PWRDN	(1 << 1)
25 #define USBPHY_OTGVDET_EN	(1 << 19)
26 #define USBPHY_OTGSESSEND_EN	(1 << 20)
27 
28 #define AM335X_PHY0_WK_EN	(1 << 0)
29 #define AM335X_PHY1_WK_EN	(1 << 8)
30 
am335x_phy_wkup(struct phy_control * phy_ctrl,u32 id,bool on)31 static void am335x_phy_wkup(struct  phy_control *phy_ctrl, u32 id, bool on)
32 {
33 	struct am335x_control_usb *usb_ctrl;
34 	u32 val;
35 	u32 reg;
36 
37 	usb_ctrl = container_of(phy_ctrl, struct am335x_control_usb, phy_ctrl);
38 
39 	switch (id) {
40 	case 0:
41 		reg = AM335X_PHY0_WK_EN;
42 		break;
43 	case 1:
44 		reg = AM335X_PHY1_WK_EN;
45 		break;
46 	default:
47 		WARN_ON(1);
48 		return;
49 	}
50 
51 	spin_lock(&usb_ctrl->lock);
52 	val = readl(usb_ctrl->wkup);
53 
54 	if (on)
55 		val |= reg;
56 	else
57 		val &= ~reg;
58 
59 	writel(val, usb_ctrl->wkup);
60 	spin_unlock(&usb_ctrl->lock);
61 }
62 
am335x_phy_power(struct phy_control * phy_ctrl,u32 id,enum usb_dr_mode dr_mode,bool on)63 static void am335x_phy_power(struct phy_control *phy_ctrl, u32 id,
64 				enum usb_dr_mode dr_mode, bool on)
65 {
66 	struct am335x_control_usb *usb_ctrl;
67 	u32 val;
68 	u32 reg;
69 
70 	usb_ctrl = container_of(phy_ctrl, struct am335x_control_usb, phy_ctrl);
71 
72 	switch (id) {
73 	case 0:
74 		reg = AM335X_USB0_CTRL;
75 		break;
76 	case 1:
77 		reg = AM335X_USB1_CTRL;
78 		break;
79 	default:
80 		WARN_ON(1);
81 		return;
82 	}
83 
84 	val = readl(usb_ctrl->phy_reg + reg);
85 	if (on) {
86 		if (dr_mode == USB_DR_MODE_HOST) {
87 			val &= ~(USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN |
88 					USBPHY_OTGVDET_EN);
89 			val |= USBPHY_OTGSESSEND_EN;
90 		} else {
91 			val &= ~(USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN);
92 			val |= USBPHY_OTGVDET_EN | USBPHY_OTGSESSEND_EN;
93 		}
94 	} else {
95 		val |= USBPHY_CM_PWRDN | USBPHY_OTG_PWRDN;
96 	}
97 
98 	writel(val, usb_ctrl->phy_reg + reg);
99 
100 	/*
101 	 * Give the PHY ~1ms to complete the power up operation.
102 	 * Tests have shown unstable behaviour if other USB PHY related
103 	 * registers are written too shortly after such a transition.
104 	 */
105 	if (on)
106 		mdelay(1);
107 }
108 
109 static const struct phy_control ctrl_am335x = {
110 	.phy_power = am335x_phy_power,
111 	.phy_wkup = am335x_phy_wkup,
112 };
113 
114 static const struct of_device_id omap_control_usb_id_table[] = {
115 	{ .compatible = "ti,am335x-usb-ctrl-module", .data = &ctrl_am335x },
116 	{}
117 };
118 MODULE_DEVICE_TABLE(of, omap_control_usb_id_table);
119 
120 static struct platform_driver am335x_control_driver;
match(struct device * dev,const void * data)121 static int match(struct device *dev, const void *data)
122 {
123 	const struct device_node *node = (const struct device_node *)data;
124 	return dev->of_node == node &&
125 		dev->driver == &am335x_control_driver.driver;
126 }
127 
am335x_get_phy_control(struct device * dev)128 struct phy_control *am335x_get_phy_control(struct device *dev)
129 {
130 	struct device_node *node;
131 	struct am335x_control_usb *ctrl_usb;
132 
133 	node = of_parse_phandle(dev->of_node, "ti,ctrl_mod", 0);
134 	if (!node)
135 		return NULL;
136 
137 	dev = bus_find_device(&platform_bus_type, NULL, node, match);
138 	of_node_put(node);
139 	if (!dev)
140 		return NULL;
141 
142 	ctrl_usb = dev_get_drvdata(dev);
143 	put_device(dev);
144 	if (!ctrl_usb)
145 		return NULL;
146 	return &ctrl_usb->phy_ctrl;
147 }
148 EXPORT_SYMBOL_GPL(am335x_get_phy_control);
149 
am335x_control_usb_probe(struct platform_device * pdev)150 static int am335x_control_usb_probe(struct platform_device *pdev)
151 {
152 	struct am335x_control_usb *ctrl_usb;
153 	const struct of_device_id *of_id;
154 	const struct phy_control *phy_ctrl;
155 
156 	of_id = of_match_node(omap_control_usb_id_table, pdev->dev.of_node);
157 	if (!of_id)
158 		return -EINVAL;
159 
160 	phy_ctrl = of_id->data;
161 
162 	ctrl_usb = devm_kzalloc(&pdev->dev, sizeof(*ctrl_usb), GFP_KERNEL);
163 	if (!ctrl_usb)
164 		return -ENOMEM;
165 
166 	ctrl_usb->dev = &pdev->dev;
167 
168 	ctrl_usb->phy_reg = devm_platform_ioremap_resource_byname(pdev, "phy_ctrl");
169 	if (IS_ERR(ctrl_usb->phy_reg))
170 		return PTR_ERR(ctrl_usb->phy_reg);
171 
172 	ctrl_usb->wkup = devm_platform_ioremap_resource_byname(pdev, "wakeup");
173 	if (IS_ERR(ctrl_usb->wkup))
174 		return PTR_ERR(ctrl_usb->wkup);
175 
176 	spin_lock_init(&ctrl_usb->lock);
177 	ctrl_usb->phy_ctrl = *phy_ctrl;
178 
179 	dev_set_drvdata(ctrl_usb->dev, ctrl_usb);
180 	return 0;
181 }
182 
183 static struct platform_driver am335x_control_driver = {
184 	.probe		= am335x_control_usb_probe,
185 	.driver		= {
186 		.name	= "am335x-control-usb",
187 		.of_match_table = omap_control_usb_id_table,
188 	},
189 };
190 
191 module_platform_driver(am335x_control_driver);
192 MODULE_DESCRIPTION("AM335x USB PHY Control Driver");
193 MODULE_LICENSE("GPL v2");
194