xref: /openbmc/linux/drivers/usb/phy/phy-am335x.c (revision 4f6cce39)
1 #include <linux/module.h>
2 #include <linux/platform_device.h>
3 #include <linux/dma-mapping.h>
4 #include <linux/usb/otg.h>
5 #include <linux/usb/usb_phy_generic.h>
6 #include <linux/slab.h>
7 #include <linux/clk.h>
8 #include <linux/of.h>
9 #include <linux/of_address.h>
10 #include <linux/usb/of.h>
11 
12 #include "phy-am335x-control.h"
13 #include "phy-generic.h"
14 
15 struct am335x_phy {
16 	struct usb_phy_generic usb_phy_gen;
17 	struct phy_control *phy_ctrl;
18 	int id;
19 	enum usb_dr_mode dr_mode;
20 };
21 
22 static int am335x_init(struct usb_phy *phy)
23 {
24 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
25 
26 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
27 	return 0;
28 }
29 
30 static void am335x_shutdown(struct usb_phy *phy)
31 {
32 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
33 
34 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
35 }
36 
37 static int am335x_phy_probe(struct platform_device *pdev)
38 {
39 	struct am335x_phy *am_phy;
40 	struct device *dev = &pdev->dev;
41 	int ret;
42 
43 	am_phy = devm_kzalloc(dev, sizeof(*am_phy), GFP_KERNEL);
44 	if (!am_phy)
45 		return -ENOMEM;
46 
47 	am_phy->phy_ctrl = am335x_get_phy_control(dev);
48 	if (!am_phy->phy_ctrl)
49 		return -EPROBE_DEFER;
50 
51 	am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
52 	if (am_phy->id < 0) {
53 		dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
54 		return am_phy->id;
55 	}
56 
57 	am_phy->dr_mode = of_usb_get_dr_mode_by_phy(pdev->dev.of_node, -1);
58 
59 	ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL);
60 	if (ret)
61 		return ret;
62 
63 	ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
64 	if (ret)
65 		return ret;
66 	am_phy->usb_phy_gen.phy.init = am335x_init;
67 	am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
68 
69 	platform_set_drvdata(pdev, am_phy);
70 	device_init_wakeup(dev, true);
71 
72 	/*
73 	 * If we leave PHY wakeup enabled then AM33XX wakes up
74 	 * immediately from DS0. To avoid this we mark dev->power.can_wakeup
75 	 * to false. The same is checked in suspend routine to decide
76 	 * on whether to enable PHY wakeup or not.
77 	 * PHY wakeup works fine in standby mode, there by allowing us to
78 	 * handle remote wakeup, wakeup on disconnect and connect.
79 	 */
80 
81 	device_set_wakeup_enable(dev, false);
82 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
83 
84 	return 0;
85 }
86 
87 static int am335x_phy_remove(struct platform_device *pdev)
88 {
89 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
90 
91 	usb_remove_phy(&am_phy->usb_phy_gen.phy);
92 	return 0;
93 }
94 
95 #ifdef CONFIG_PM_SLEEP
96 static int am335x_phy_suspend(struct device *dev)
97 {
98 	struct platform_device	*pdev = to_platform_device(dev);
99 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
100 
101 	/*
102 	 * Enable phy wakeup only if dev->power.can_wakeup is true.
103 	 * Make sure to enable wakeup to support remote wakeup	in
104 	 * standby mode ( same is not supported in OFF(DS0) mode).
105 	 * Enable it by doing
106 	 * echo enabled > /sys/bus/platform/devices/<usb-phy-id>/power/wakeup
107 	 */
108 
109 	if (device_may_wakeup(dev))
110 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, true);
111 
112 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, false);
113 
114 	return 0;
115 }
116 
117 static int am335x_phy_resume(struct device *dev)
118 {
119 	struct platform_device	*pdev = to_platform_device(dev);
120 	struct am335x_phy	*am_phy = platform_get_drvdata(pdev);
121 
122 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, am_phy->dr_mode, true);
123 
124 	if (device_may_wakeup(dev))
125 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
126 
127 	return 0;
128 }
129 #endif
130 
131 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
132 
133 static const struct of_device_id am335x_phy_ids[] = {
134 	{ .compatible = "ti,am335x-usb-phy" },
135 	{ }
136 };
137 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
138 
139 static struct platform_driver am335x_phy_driver = {
140 	.probe          = am335x_phy_probe,
141 	.remove         = am335x_phy_remove,
142 	.driver         = {
143 		.name   = "am335x-phy-driver",
144 		.pm = &am335x_pm_ops,
145 		.of_match_table = am335x_phy_ids,
146 	},
147 };
148 
149 module_platform_driver(am335x_phy_driver);
150 MODULE_LICENSE("GPL v2");
151