xref: /openbmc/linux/drivers/usb/phy/phy-am335x.c (revision ca55b2fe)
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/regulator/consumer.h>
9 #include <linux/of.h>
10 #include <linux/of_address.h>
11 
12 #include "am35x-phy-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 };
20 
21 static int am335x_init(struct usb_phy *phy)
22 {
23 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
24 
25 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, true);
26 	return 0;
27 }
28 
29 static void am335x_shutdown(struct usb_phy *phy)
30 {
31 	struct am335x_phy *am_phy = dev_get_drvdata(phy->dev);
32 
33 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
34 }
35 
36 static int am335x_phy_probe(struct platform_device *pdev)
37 {
38 	struct am335x_phy *am_phy;
39 	struct device *dev = &pdev->dev;
40 	int ret;
41 
42 	am_phy = devm_kzalloc(dev, sizeof(*am_phy), GFP_KERNEL);
43 	if (!am_phy)
44 		return -ENOMEM;
45 
46 	am_phy->phy_ctrl = am335x_get_phy_control(dev);
47 	if (!am_phy->phy_ctrl)
48 		return -EPROBE_DEFER;
49 	am_phy->id = of_alias_get_id(pdev->dev.of_node, "phy");
50 	if (am_phy->id < 0) {
51 		dev_err(&pdev->dev, "Missing PHY id: %d\n", am_phy->id);
52 		return am_phy->id;
53 	}
54 
55 	ret = usb_phy_gen_create_phy(dev, &am_phy->usb_phy_gen, NULL);
56 	if (ret)
57 		return ret;
58 
59 	ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
60 	if (ret)
61 		return ret;
62 	am_phy->usb_phy_gen.phy.init = am335x_init;
63 	am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
64 
65 	platform_set_drvdata(pdev, am_phy);
66 	device_init_wakeup(dev, true);
67 
68 	/*
69 	 * If we leave PHY wakeup enabled then AM33XX wakes up
70 	 * immediately from DS0. To avoid this we mark dev->power.can_wakeup
71 	 * to false. The same is checked in suspend routine to decide
72 	 * on whether to enable PHY wakeup or not.
73 	 * PHY wakeup works fine in standby mode, there by allowing us to
74 	 * handle remote wakeup, wakeup on disconnect and connect.
75 	 */
76 
77 	device_set_wakeup_enable(dev, false);
78 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
79 
80 	return 0;
81 }
82 
83 static int am335x_phy_remove(struct platform_device *pdev)
84 {
85 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
86 
87 	usb_remove_phy(&am_phy->usb_phy_gen.phy);
88 	return 0;
89 }
90 
91 #ifdef CONFIG_PM_SLEEP
92 static int am335x_phy_suspend(struct device *dev)
93 {
94 	struct platform_device	*pdev = to_platform_device(dev);
95 	struct am335x_phy *am_phy = platform_get_drvdata(pdev);
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, false);
109 
110 	return 0;
111 }
112 
113 static int am335x_phy_resume(struct device *dev)
114 {
115 	struct platform_device	*pdev = to_platform_device(dev);
116 	struct am335x_phy	*am_phy = platform_get_drvdata(pdev);
117 
118 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, true);
119 
120 	if (device_may_wakeup(dev))
121 		phy_ctrl_wkup(am_phy->phy_ctrl, am_phy->id, false);
122 
123 	return 0;
124 }
125 #endif
126 
127 static SIMPLE_DEV_PM_OPS(am335x_pm_ops, am335x_phy_suspend, am335x_phy_resume);
128 
129 static const struct of_device_id am335x_phy_ids[] = {
130 	{ .compatible = "ti,am335x-usb-phy" },
131 	{ }
132 };
133 MODULE_DEVICE_TABLE(of, am335x_phy_ids);
134 
135 static struct platform_driver am335x_phy_driver = {
136 	.probe          = am335x_phy_probe,
137 	.remove         = am335x_phy_remove,
138 	.driver         = {
139 		.name   = "am335x-phy-driver",
140 		.pm = &am335x_pm_ops,
141 		.of_match_table = am335x_phy_ids,
142 	},
143 };
144 
145 module_platform_driver(am335x_phy_driver);
146 MODULE_LICENSE("GPL v2");
147