1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * OMAP OTG controller driver
4 *
5 * Based on code from tahvo-usb.c and isp1301_omap.c drivers.
6 *
7 * Copyright (C) 2005-2006 Nokia Corporation
8 * Copyright (C) 2004 Texas Instruments
9 * Copyright (C) 2004 David Brownell
10 */
11
12 #include <linux/io.h>
13 #include <linux/err.h>
14 #include <linux/extcon.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/platform_device.h>
19 #include <linux/platform_data/usb-omap1.h>
20
21 struct otg_device {
22 void __iomem *base;
23 bool id;
24 bool vbus;
25 struct extcon_dev *extcon;
26 struct notifier_block vbus_nb;
27 struct notifier_block id_nb;
28 };
29
30 #define OMAP_OTG_CTRL 0x0c
31 #define OMAP_OTG_ASESSVLD (1 << 20)
32 #define OMAP_OTG_BSESSEND (1 << 19)
33 #define OMAP_OTG_BSESSVLD (1 << 18)
34 #define OMAP_OTG_VBUSVLD (1 << 17)
35 #define OMAP_OTG_ID (1 << 16)
36 #define OMAP_OTG_XCEIV_OUTPUTS \
37 (OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \
38 OMAP_OTG_VBUSVLD | OMAP_OTG_ID)
39
omap_otg_ctrl(struct otg_device * otg_dev,u32 outputs)40 static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs)
41 {
42 u32 l;
43
44 l = readl(otg_dev->base + OMAP_OTG_CTRL);
45 l &= ~OMAP_OTG_XCEIV_OUTPUTS;
46 l |= outputs;
47 writel(l, otg_dev->base + OMAP_OTG_CTRL);
48 }
49
omap_otg_set_mode(struct otg_device * otg_dev)50 static void omap_otg_set_mode(struct otg_device *otg_dev)
51 {
52 if (!otg_dev->id && otg_dev->vbus)
53 /* Set B-session valid. */
54 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD);
55 else if (otg_dev->vbus)
56 /* Set A-session valid. */
57 omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD);
58 else if (!otg_dev->id)
59 /* Set B-session end to indicate no VBUS. */
60 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND);
61 }
62
omap_otg_id_notifier(struct notifier_block * nb,unsigned long event,void * ptr)63 static int omap_otg_id_notifier(struct notifier_block *nb,
64 unsigned long event, void *ptr)
65 {
66 struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb);
67
68 otg_dev->id = event;
69 omap_otg_set_mode(otg_dev);
70
71 return NOTIFY_DONE;
72 }
73
omap_otg_vbus_notifier(struct notifier_block * nb,unsigned long event,void * ptr)74 static int omap_otg_vbus_notifier(struct notifier_block *nb,
75 unsigned long event, void *ptr)
76 {
77 struct otg_device *otg_dev = container_of(nb, struct otg_device,
78 vbus_nb);
79
80 otg_dev->vbus = event;
81 omap_otg_set_mode(otg_dev);
82
83 return NOTIFY_DONE;
84 }
85
omap_otg_probe(struct platform_device * pdev)86 static int omap_otg_probe(struct platform_device *pdev)
87 {
88 const struct omap_usb_config *config = pdev->dev.platform_data;
89 struct otg_device *otg_dev;
90 struct extcon_dev *extcon;
91 int ret;
92 u32 rev;
93
94 if (!config || !config->extcon)
95 return -ENODEV;
96
97 extcon = extcon_get_extcon_dev(config->extcon);
98 if (IS_ERR(extcon))
99 return PTR_ERR(extcon);
100
101 otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL);
102 if (!otg_dev)
103 return -ENOMEM;
104
105 otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]);
106 if (IS_ERR(otg_dev->base))
107 return PTR_ERR(otg_dev->base);
108
109 otg_dev->extcon = extcon;
110 otg_dev->id_nb.notifier_call = omap_otg_id_notifier;
111 otg_dev->vbus_nb.notifier_call = omap_otg_vbus_notifier;
112
113 ret = devm_extcon_register_notifier(&pdev->dev, extcon,
114 EXTCON_USB_HOST, &otg_dev->id_nb);
115 if (ret)
116 return ret;
117
118 ret = devm_extcon_register_notifier(&pdev->dev, extcon,
119 EXTCON_USB, &otg_dev->vbus_nb);
120 if (ret) {
121 return ret;
122 }
123
124 otg_dev->id = extcon_get_state(extcon, EXTCON_USB_HOST);
125 otg_dev->vbus = extcon_get_state(extcon, EXTCON_USB);
126 omap_otg_set_mode(otg_dev);
127
128 rev = readl(otg_dev->base);
129
130 dev_info(&pdev->dev,
131 "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n",
132 (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id,
133 otg_dev->vbus);
134
135 platform_set_drvdata(pdev, otg_dev);
136
137 return 0;
138 }
139
140 static struct platform_driver omap_otg_driver = {
141 .probe = omap_otg_probe,
142 .driver = {
143 .name = "omap_otg",
144 },
145 };
146 module_platform_driver(omap_otg_driver);
147
148 MODULE_DESCRIPTION("OMAP USB OTG controller driver");
149 MODULE_LICENSE("GPL");
150 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
151