xref: /openbmc/linux/drivers/usb/phy/phy-isp1301.c (revision f7d84fa7)
1 /*
2  * NXP ISP1301 USB transceiver driver
3  *
4  * Copyright (C) 2012 Roland Stigge
5  *
6  * Author: Roland Stigge <stigge@antcom.de>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/i2c.h>
16 #include <linux/usb/phy.h>
17 #include <linux/usb/isp1301.h>
18 
19 #define DRV_NAME		"isp1301"
20 
21 struct isp1301 {
22 	struct usb_phy		phy;
23 	struct mutex		mutex;
24 
25 	struct i2c_client	*client;
26 };
27 
28 #define phy_to_isp(p)		(container_of((p), struct isp1301, phy))
29 
30 static const struct i2c_device_id isp1301_id[] = {
31 	{ "isp1301", 0 },
32 	{ }
33 };
34 MODULE_DEVICE_TABLE(i2c, isp1301_id);
35 
36 static const struct of_device_id isp1301_of_match[] = {
37 	{.compatible = "nxp,isp1301" },
38 	{ },
39 };
40 MODULE_DEVICE_TABLE(of, isp1301_of_match);
41 
42 static struct i2c_client *isp1301_i2c_client;
43 
44 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
45 {
46 	return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
47 }
48 
49 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
50 {
51 	return __isp1301_write(isp, reg, value, 0);
52 }
53 
54 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
55 {
56 	return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
57 }
58 
59 static int isp1301_phy_init(struct usb_phy *phy)
60 {
61 	struct isp1301 *isp = phy_to_isp(phy);
62 
63 	/* Disable transparent UART mode first */
64 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
65 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
66 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
67 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
68 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
69 				| MC2_SPD_SUSP_CTRL));
70 
71 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
72 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
73 	isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
74 				| OTG1_DP_PULLDOWN));
75 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
76 				| OTG1_DP_PULLUP));
77 
78 	/* mask all interrupts */
79 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
80 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
81 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
82 
83 	return 0;
84 }
85 
86 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
87 {
88 	struct isp1301 *isp = phy_to_isp(phy);
89 
90 	if (on)
91 		isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
92 	else
93 		isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
94 
95 	return 0;
96 }
97 
98 static int isp1301_probe(struct i2c_client *client,
99 			 const struct i2c_device_id *i2c_id)
100 {
101 	struct isp1301 *isp;
102 	struct usb_phy *phy;
103 
104 	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
105 	if (!isp)
106 		return -ENOMEM;
107 
108 	isp->client = client;
109 	mutex_init(&isp->mutex);
110 
111 	phy = &isp->phy;
112 	phy->dev = &client->dev;
113 	phy->label = DRV_NAME;
114 	phy->init = isp1301_phy_init;
115 	phy->set_vbus = isp1301_phy_set_vbus;
116 	phy->type = USB_PHY_TYPE_USB2;
117 
118 	i2c_set_clientdata(client, isp);
119 	usb_add_phy_dev(phy);
120 
121 	isp1301_i2c_client = client;
122 
123 	return 0;
124 }
125 
126 static int isp1301_remove(struct i2c_client *client)
127 {
128 	struct isp1301 *isp = i2c_get_clientdata(client);
129 
130 	usb_remove_phy(&isp->phy);
131 	isp1301_i2c_client = NULL;
132 
133 	return 0;
134 }
135 
136 static struct i2c_driver isp1301_driver = {
137 	.driver = {
138 		.name = DRV_NAME,
139 		.of_match_table = isp1301_of_match,
140 	},
141 	.probe = isp1301_probe,
142 	.remove = isp1301_remove,
143 	.id_table = isp1301_id,
144 };
145 
146 module_i2c_driver(isp1301_driver);
147 
148 static int match(struct device *dev, void *data)
149 {
150 	struct device_node *node = (struct device_node *)data;
151 	return (dev->of_node == node) &&
152 		(dev->driver == &isp1301_driver.driver);
153 }
154 
155 struct i2c_client *isp1301_get_client(struct device_node *node)
156 {
157 	if (node) { /* reference of ISP1301 I2C node via DT */
158 		struct device *dev = bus_find_device(&i2c_bus_type, NULL,
159 						     node, match);
160 		if (!dev)
161 			return NULL;
162 		return to_i2c_client(dev);
163 	} else { /* non-DT: only one ISP1301 chip supported */
164 		return isp1301_i2c_client;
165 	}
166 }
167 EXPORT_SYMBOL_GPL(isp1301_get_client);
168 
169 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
170 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
171 MODULE_LICENSE("GPL");
172