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 
__isp1301_write(struct isp1301 * isp,u8 reg,u8 value,u8 clear)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 
isp1301_write(struct isp1301 * isp,u8 reg,u8 value)46 static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
47 {
48 	return __isp1301_write(isp, reg, value, 0);
49 }
50 
isp1301_clear(struct isp1301 * isp,u8 reg,u8 value)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 
isp1301_phy_init(struct usb_phy * phy)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 
isp1301_phy_set_vbus(struct usb_phy * phy,int on)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 
isp1301_probe(struct i2c_client * client)95 static int isp1301_probe(struct i2c_client *client)
96 {
97 	struct isp1301 *isp;
98 	struct usb_phy *phy;
99 
100 	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
101 	if (!isp)
102 		return -ENOMEM;
103 
104 	isp->client = client;
105 	mutex_init(&isp->mutex);
106 
107 	phy = &isp->phy;
108 	phy->dev = &client->dev;
109 	phy->label = DRV_NAME;
110 	phy->init = isp1301_phy_init;
111 	phy->set_vbus = isp1301_phy_set_vbus;
112 	phy->type = USB_PHY_TYPE_USB2;
113 
114 	i2c_set_clientdata(client, isp);
115 	usb_add_phy_dev(phy);
116 
117 	isp1301_i2c_client = client;
118 
119 	return 0;
120 }
121 
isp1301_remove(struct i2c_client * client)122 static void isp1301_remove(struct i2c_client *client)
123 {
124 	struct isp1301 *isp = i2c_get_clientdata(client);
125 
126 	usb_remove_phy(&isp->phy);
127 	isp1301_i2c_client = NULL;
128 }
129 
130 static struct i2c_driver isp1301_driver = {
131 	.driver = {
132 		.name = DRV_NAME,
133 		.of_match_table = isp1301_of_match,
134 	},
135 	.probe_new = isp1301_probe,
136 	.remove = isp1301_remove,
137 	.id_table = isp1301_id,
138 };
139 
140 module_i2c_driver(isp1301_driver);
141 
isp1301_get_client(struct device_node * node)142 struct i2c_client *isp1301_get_client(struct device_node *node)
143 {
144 	struct i2c_client *client;
145 
146 	/* reference of ISP1301 I2C node via DT */
147 	client = of_find_i2c_device_by_node(node);
148 	if (client)
149 		return client;
150 
151 	/* non-DT: only one ISP1301 chip supported */
152 	return isp1301_i2c_client;
153 }
154 EXPORT_SYMBOL_GPL(isp1301_get_client);
155 
156 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
157 MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
158 MODULE_LICENSE("GPL");
159