xref: /openbmc/linux/drivers/usb/phy/phy-isp1301.c (revision 9cfc5c90)
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 struct i2c_client *isp1301_i2c_client;
37 
38 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
39 {
40 	return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
41 }
42 
43 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
44 {
45 	return __isp1301_write(isp, reg, value, 0);
46 }
47 
48 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
49 {
50 	return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
51 }
52 
53 static int isp1301_phy_init(struct usb_phy *phy)
54 {
55 	struct isp1301 *isp = phy_to_isp(phy);
56 
57 	/* Disable transparent UART mode first */
58 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
59 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
60 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
61 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
62 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
63 				| MC2_SPD_SUSP_CTRL));
64 
65 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
66 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
67 	isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
68 				| OTG1_DP_PULLDOWN));
69 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
70 				| OTG1_DP_PULLUP));
71 
72 	/* mask all interrupts */
73 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
74 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
75 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
76 
77 	return 0;
78 }
79 
80 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
81 {
82 	struct isp1301 *isp = phy_to_isp(phy);
83 
84 	if (on)
85 		isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
86 	else
87 		isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
88 
89 	return 0;
90 }
91 
92 static int isp1301_probe(struct i2c_client *client,
93 			 const struct i2c_device_id *i2c_id)
94 {
95 	struct isp1301 *isp;
96 	struct usb_phy *phy;
97 
98 	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
99 	if (!isp)
100 		return -ENOMEM;
101 
102 	isp->client = client;
103 	mutex_init(&isp->mutex);
104 
105 	phy = &isp->phy;
106 	phy->dev = &client->dev;
107 	phy->label = DRV_NAME;
108 	phy->init = isp1301_phy_init;
109 	phy->set_vbus = isp1301_phy_set_vbus;
110 	phy->type = USB_PHY_TYPE_USB2;
111 
112 	i2c_set_clientdata(client, isp);
113 	usb_add_phy_dev(phy);
114 
115 	isp1301_i2c_client = client;
116 
117 	return 0;
118 }
119 
120 static int isp1301_remove(struct i2c_client *client)
121 {
122 	struct isp1301 *isp = i2c_get_clientdata(client);
123 
124 	usb_remove_phy(&isp->phy);
125 	isp1301_i2c_client = NULL;
126 
127 	return 0;
128 }
129 
130 static struct i2c_driver isp1301_driver = {
131 	.driver = {
132 		.name = DRV_NAME,
133 	},
134 	.probe = isp1301_probe,
135 	.remove = isp1301_remove,
136 	.id_table = isp1301_id,
137 };
138 
139 module_i2c_driver(isp1301_driver);
140 
141 static int match(struct device *dev, void *data)
142 {
143 	struct device_node *node = (struct device_node *)data;
144 	return (dev->of_node == node) &&
145 		(dev->driver == &isp1301_driver.driver);
146 }
147 
148 struct i2c_client *isp1301_get_client(struct device_node *node)
149 {
150 	if (node) { /* reference of ISP1301 I2C node via DT */
151 		struct device *dev = bus_find_device(&i2c_bus_type, NULL,
152 						     node, match);
153 		if (!dev)
154 			return NULL;
155 		return to_i2c_client(dev);
156 	} else { /* non-DT: only one ISP1301 chip supported */
157 		return isp1301_i2c_client;
158 	}
159 }
160 EXPORT_SYMBOL_GPL(isp1301_get_client);
161 
162 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
163 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
164 MODULE_LICENSE("GPL");
165