xref: /openbmc/linux/drivers/usb/phy/phy-am335x.c (revision c123905f)
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 
am335x_init(struct usb_phy * phy)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 
am335x_shutdown(struct usb_phy * phy)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 
am335x_phy_probe(struct platform_device * pdev)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);
61 	if (ret)
62 		return ret;
63 
64 	am_phy->usb_phy_gen.phy.init = am335x_init;
65 	am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
66 
67 	platform_set_drvdata(pdev, am_phy);
68 	device_init_wakeup(dev, true);
69 
70 	/*
71 	 * If we leave PHY wakeup enabled then AM33XX wakes up
72 	 * immediately from DS0. To avoid this we mark dev->power.can_wakeup
73 	 * to false. The same is checked in suspend routine to decide
74 	 * on whether to enable PHY wakeup or not.
75 	 * PHY wakeup works fine in standby mode, there by allowing us to
76 	 * handle remote wakeup, wakeup on disconnect and connect.
77 	 */
78 
79 	device_set_wakeup_enable(dev, false);
80 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
81 
82 	return usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
83 }
84 
am335x_phy_remove(struct platform_device * pdev)85 static void am335x_phy_remove(struct platform_device *pdev)
86 {
87 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
88 
89 	usb_remove_phy(&am_phy->usb_phy_gen.phy);
90 }
91 
92 #ifdef CONFIG_PM_SLEEP
am335x_phy_suspend(struct device * dev)93 static int am335x_phy_suspend(struct device *dev)
94 {
95 	struct am335x_phy *am_phy = dev_get_drvdata(dev);
96 
97 	/*
98 	 * Enable phy wakeup only if dev->power.can_wakeup is true.
99 	 * Make sure to enable wakeup to support remote wakeup	in
100 	 * standby mode ( same is not supported in OFF(DS0) mode).
101 	 * Enable it by doing
102 	 * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
103 	 */
104 
105 	if (device_may_wakeup(dev))
106 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
107 
108 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
109 
110 	return 0;
111 }
112 
am335x_phy_resume(struct device * dev)113 static int am335x_phy_resume(struct device *dev)
114 {
115 	struct am335x_phy	*am_phy = dev_get_drvdata(dev);
116 
117 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
118 
119 	if (device_may_wakeup(dev))
120 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
121 
122 	return 0;
123 }
124 #endif
125 
126 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
127 
128 static const struct of_device_id am335x_phy_ids[] = {
129 	{ .compatible = "ti,am335x-usb-phy" },
130 	{ }
131 };
132 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
133 
134 static struct platform_driver am335x_phy_driver = {
135 	.probe          = am335x_phy_probe,
136 	.remove_new     = am335x_phy_remove,
137 	.driver         = {
138 		.name   = "am335x-phy-driver",
139 		.pm = &am335x_pm_ops,
140 		.of_match_table = am335x_phy_ids,
141 	},
142 };
143 
144 module_platform_driver(am335x_phy_driver);
145 MODULE_LICENSE("GPL v2");
146