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
18struct 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
27static const struct i2c_device_id isp1301_id[] = {
28	{ "isp1301", 0 },
29	{ }
30};
31MODULE_DEVICE_TABLE(i2c, isp1301_id);
32
33static const struct of_device_id isp1301_of_match[] = {
34	{.compatible = "nxp,isp1301" },
35	{ },
36};
37MODULE_DEVICE_TABLE(of, isp1301_of_match);
38
39static struct i2c_client *isp1301_i2c_client;
40
41static 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
46static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
47{
48	return __isp1301_write(isp, reg, value, 0);
49}
50
51static 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
56static 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
83static 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
95static 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
123static int 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	return 0;
131}
132
133static struct i2c_driver isp1301_driver = {
134	.driver = {
135		.name = DRV_NAME,
136		.of_match_table = isp1301_of_match,
137	},
138	.probe = isp1301_probe,
139	.remove = isp1301_remove,
140	.id_table = isp1301_id,
141};
142
143module_i2c_driver(isp1301_driver);
144
145static int match(struct device *dev, const void *data)
146{
147	const struct device_node *node = (const struct device_node *)data;
148	return (dev->of_node == node) &&
149		(dev->driver == &isp1301_driver.driver);
150}
151
152struct i2c_client *isp1301_get_client(struct device_node *node)
153{
154	if (node) { /* reference of ISP1301 I2C node via DT */
155		struct device *dev = bus_find_device(&i2c_bus_type, NULL,
156						     node, match);
157		if (!dev)
158			return NULL;
159		return to_i2c_client(dev);
160	} else { /* non-DT: only one ISP1301 chip supported */
161		return isp1301_i2c_client;
162	}
163}
164EXPORT_SYMBOL_GPL(isp1301_get_client);
165
166MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
167MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
168MODULE_LICENSE("GPL");
169