xref: /openbmc/linux/drivers/usb/phy/phy-am335x.c (revision 2359ccdd)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/module.h>
3 #include <linux/platform_device.h>
4 #include <linux/dma-mapping.h>
5 #include <linux/usb/otg.h>
6 #include <linux/usb/usb_phy_generic.h>
7 #include <linux/slab.h>
8 #include <linux/clk.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 #include <linux/usb/of.h>
12 
13 #include "phy-am335x-control.h"
14 #include "phy-generic.h"
15 
16 struct am335x_phy {
17 	struct usb_phy_generic usb_phy_gen;
18 	struct phy_control *phy_ctrl;
19 	int id;
20 	enum usb_dr_mode dr_mode;
21 };
22 
23 static int am335x_init(struct usb_phy *phy)
24 {
25 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
26 
27 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
28 	return 0;
29 }
30 
31 static void am335x_shutdown(struct usb_phy *phy)
32 {
33 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
34 
35 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
36 }
37 
38 static int am335x_phy_probe(struct platform_device *pdev)
39 {
40 	struct am335x_phy *am_phy;
41 	struct device *dev = &pdev->dev;
42 	int ret;
43 
44 	am_phy = devm_kzalloc(dev, sizeof(*am_phy), GFP_KERNEL);
45 	if (!am_phy)
46 		return -ENOMEM;
47 
48 	am_phy->phy_ctrl = am335x_get_phy_control(dev);
49 	if (!am_phy->phy_ctrl)
50 		return -EPROBE_DEFER;
51 
52 	am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
53 	if (am_phy->id < 0) {
54 		dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
55 		return am_phy->id;
56 	}
57 
58 	am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1);
59 
60 	ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL);
61 	if (ret)
62 		return ret;
63 
64 	ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
65 	if (ret)
66 		return ret;
67 	am_phy->usb_phy_gen.phy.init = am335x_init;
68 	am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
69 
70 	platform_set_drvdata(pdev, am_phy);
71 	device_init_wakeup(dev, true);
72 
73 	/*
74 	 * If we leave PHY wakeup enabled then AM33XX wakes up
75 	 * immediately from DS0. To avoid this we mark dev->power.can_wakeup
76 	 * to false. The same is checked in suspend routine to decide
77 	 * on whether to enable PHY wakeup or not.
78 	 * PHY wakeup works fine in standby mode, there by allowing us to
79 	 * handle remote wakeup, wakeup on disconnect and connect.
80 	 */
81 
82 	device_set_wakeup_enable(dev, false);
83 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
84 
85 	return 0;
86 }
87 
88 static int am335x_phy_remove(struct platform_device *pdev)
89 {
90 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
91 
92 	usb_remove_phy(&am_phy->usb_phy_gen.phy);
93 	return 0;
94 }
95 
96 #ifdef CONFIG_PM_SLEEP
97 static int am335x_phy_suspend(struct device *dev)
98 {
99 	struct platform_device	*pdev = to_platform_device(dev);
100 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
101 
102 	/*
103 	 * Enable phy wakeup only if dev->power.can_wakeup is true.
104 	 * Make sure to enable wakeup to support remote wakeup	in
105 	 * standby mode ( same is not supported in OFF(DS0) mode).
106 	 * Enable it by doing
107 	 * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
108 	 */
109 
110 	if (device_may_wakeup(dev))
111 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
112 
113 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
114 
115 	return 0;
116 }
117 
118 static int am335x_phy_resume(struct device *dev)
119 {
120 	struct platform_device	*pdev = to_platform_device(dev);
121 	struct am335x_phy	*am_phy = platform_get_drvdata(pdev);
122 
123 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
124 
125 	if (device_may_wakeup(dev))
126 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
127 
128 	return 0;
129 }
130 #endif
131 
132 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
133 
134 static const struct of_device_id am335x_phy_ids[] = {
135 	{ .compatible = "ti,am335x-usb-phy" },
136 	{ }
137 };
138 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
139 
140 static struct platform_driver am335x_phy_driver = {
141 	.probe          = am335x_phy_probe,
142 	.remove         = am335x_phy_remove,
143 	.driver         = {
144 		.name   = "am335x-phy-driver",
145 		.pm = &am335x_pm_ops,
146 		.of_match_table = am335x_phy_ids,
147 	},
148 };
149 
150 module_platform_driver(am335x_phy_driver);
151 MODULE_LICENSE("GPL v2");
152