xref: /linux/drivers/usb/phy/phy-isp1301.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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 
35 static struct i2c_client *isp1301_i2c_client;
36 
37 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
38 {
39 	return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
40 }
41 
42 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
43 {
44 	return __isp1301_write(isp, reg, value, 0);
45 }
46 
47 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
48 {
49 	return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
50 }
51 
52 static int isp1301_phy_init(struct usb_phy *phy)
53 {
54 	struct isp1301 *isp = phy_to_isp(phy);
55 
56 	/* Disable transparent UART mode first */
57 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
58 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
59 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
60 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
61 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
62 				| MC2_SPD_SUSP_CTRL));
63 
64 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
65 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
66 	isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
67 				| OTG1_DP_PULLDOWN));
68 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
69 				| OTG1_DP_PULLUP));
70 
71 	/* mask all interrupts */
72 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
73 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
74 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
75 
76 	return 0;
77 }
78 
79 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
80 {
81 	struct isp1301 *isp = phy_to_isp(phy);
82 
83 	if (on)
84 		isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
85 	else
86 		isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
87 
88 	return 0;
89 }
90 
91 static int isp1301_probe(struct i2c_client *client,
92 			 const struct i2c_device_id *i2c_id)
93 {
94 	struct isp1301 *isp;
95 	struct usb_phy *phy;
96 
97 	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
98 	if (!isp)
99 		return -ENOMEM;
100 
101 	isp->client = client;
102 	mutex_init(&isp->mutex);
103 
104 	phy = &isp->phy;
105 	phy->dev = &client->dev;
106 	phy->label = DRV_NAME;
107 	phy->init = isp1301_phy_init;
108 	phy->set_vbus = isp1301_phy_set_vbus;
109 	phy->type = USB_PHY_TYPE_USB2;
110 
111 	i2c_set_clientdata(client, isp);
112 	usb_add_phy_dev(phy);
113 
114 	isp1301_i2c_client = client;
115 
116 	return 0;
117 }
118 
119 static int isp1301_remove(struct i2c_client *client)
120 {
121 	struct isp1301 *isp = i2c_get_clientdata(client);
122 
123 	usb_remove_phy(&isp->phy);
124 	isp1301_i2c_client = NULL;
125 
126 	return 0;
127 }
128 
129 static struct i2c_driver isp1301_driver = {
130 	.driver = {
131 		.name = DRV_NAME,
132 	},
133 	.probe = isp1301_probe,
134 	.remove = isp1301_remove,
135 	.id_table = isp1301_id,
136 };
137 
138 module_i2c_driver(isp1301_driver);
139 
140 static int match(struct device *dev, void *data)
141 {
142 	struct device_node *node = (struct device_node *)data;
143 	return (dev->of_node == node) &&
144 		(dev->driver == &isp1301_driver.driver);
145 }
146 
147 struct i2c_client *isp1301_get_client(struct device_node *node)
148 {
149 	if (node) { /* reference of ISP1301 I2C node via DT */
150 		struct device *dev = bus_find_device(&i2c_bus_type, NULL,
151 						     node, match);
152 		if (!dev)
153 			return NULL;
154 		return to_i2c_client(dev);
155 	} else { /* non-DT: only one ISP1301 chip supported */
156 		return isp1301_i2c_client;
157 	}
158 }
159 EXPORT_SYMBOL_GPL(isp1301_get_client);
160 
161 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
162 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
163 MODULE_LICENSE("GPL");
164