xref: /openbmc/linux/drivers/usb/phy/phy-isp1301.c (revision 0352f880)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * NXP ISP1301 USB transceiver driver
4  *
5  * Copyright (C) 2012 Roland Stigge
6  *
7  * Author: Roland Stigge <stigge@antcom.de>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/i2c.h>
13 #include <linux/usb/phy.h>
14 #include <linux/usb/isp1301.h>
15 
16 #define DRV_NAME		"isp1301"
17 
18 struct isp1301 {
19 	struct usb_phy		phy;
20 	struct mutex		mutex;
21 
22 	struct i2c_client	*client;
23 };
24 
25 #define phy_to_isp(p)		(container_of((p), struct isp1301, phy))
26 
27 static const struct i2c_device_id isp1301_id[] = {
28 	{ "isp1301", 0 },
29 	{ }
30 };
31 MODULE_DEVICE_TABLE(i2c, isp1301_id);
32 
33 static const struct of_device_id isp1301_of_match[] = {
34 	{.compatible = "nxp,isp1301" },
35 	{ },
36 };
37 MODULE_DEVICE_TABLE(of, isp1301_of_match);
38 
39 static struct i2c_client *isp1301_i2c_client;
40 
41 static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
42 {
43 	return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
44 }
45 
46 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
47 {
48 	return __isp1301_write(isp, reg, value, 0);
49 }
50 
51 static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
52 {
53 	return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
54 }
55 
56 static int isp1301_phy_init(struct usb_phy *phy)
57 {
58 	struct isp1301 *isp = phy_to_isp(phy);
59 
60 	/* Disable transparent UART mode first */
61 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
62 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
63 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
64 	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
65 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
66 				| MC2_SPD_SUSP_CTRL));
67 
68 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
69 	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
70 	isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
71 				| OTG1_DP_PULLDOWN));
72 	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
73 				| OTG1_DP_PULLUP));
74 
75 	/* mask all interrupts */
76 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
77 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
78 	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
79 
80 	return 0;
81 }
82 
83 static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
84 {
85 	struct isp1301 *isp = phy_to_isp(phy);
86 
87 	if (on)
88 		isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
89 	else
90 		isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
91 
92 	return 0;
93 }
94 
95 static int isp1301_probe(struct i2c_client *client,
96 			 const struct i2c_device_id *i2c_id)
97 {
98 	struct isp1301 *isp;
99 	struct usb_phy *phy;
100 
101 	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
102 	if (!isp)
103 		return -ENOMEM;
104 
105 	isp->client = client;
106 	mutex_init(&isp->mutex);
107 
108 	phy = &isp->phy;
109 	phy->dev = &client->dev;
110 	phy->label = DRV_NAME;
111 	phy->init = isp1301_phy_init;
112 	phy->set_vbus = isp1301_phy_set_vbus;
113 	phy->type = USB_PHY_TYPE_USB2;
114 
115 	i2c_set_clientdata(client, isp);
116 	usb_add_phy_dev(phy);
117 
118 	isp1301_i2c_client = client;
119 
120 	return 0;
121 }
122 
123 static void isp1301_remove(struct i2c_client *client)
124 {
125 	struct isp1301 *isp = i2c_get_clientdata(client);
126 
127 	usb_remove_phy(&isp->phy);
128 	isp1301_i2c_client = NULL;
129 }
130 
131 static struct i2c_driver isp1301_driver = {
132 	.driver = {
133 		.name = DRV_NAME,
134 		.of_match_table = isp1301_of_match,
135 	},
136 	.probe = isp1301_probe,
137 	.remove = isp1301_remove,
138 	.id_table = isp1301_id,
139 };
140 
141 module_i2c_driver(isp1301_driver);
142 
143 struct i2c_client *isp1301_get_client(struct device_node *node)
144 {
145 	struct i2c_client *client;
146 
147 	/* reference of ISP1301 I2C node via DT */
148 	client = of_find_i2c_device_by_node(node);
149 	if (client)
150 		return client;
151 
152 	/* non-DT: only one ISP1301 chip supported */
153 	return isp1301_i2c_client;
154 }
155 EXPORT_SYMBOL_GPL(isp1301_get_client);
156 
157 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
158 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
159 MODULE_LICENSE("GPL");
160