1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Pericom PI3USB30532 Type-C cross switch / mux driver
4  *
5  * Copyright (c) 2017-2018 Hans de Goede <hdegoede@redhat.com>
6  */
7 
8 #include <linux/i2c.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/mutex.h>
12 #include <linux/usb/typec_dp.h>
13 #include <linux/usb/typec_mux.h>
14 
15 #define PI3USB30532_CONF			0x00
16 
17 #define PI3USB30532_CONF_OPEN			0x00
18 #define PI3USB30532_CONF_SWAP			0x01
19 #define PI3USB30532_CONF_4LANE_DP		0x02
20 #define PI3USB30532_CONF_USB3			0x04
21 #define PI3USB30532_CONF_USB3_AND_2LANE_DP	0x06
22 
23 struct pi3usb30532 {
24 	struct i2c_client *client;
25 	struct mutex lock; /* protects the cached conf register */
26 	struct typec_switch *sw;
27 	struct typec_mux *mux;
28 	u8 conf;
29 };
30 
pi3usb30532_set_conf(struct pi3usb30532 * pi,u8 new_conf)31 static int pi3usb30532_set_conf(struct pi3usb30532 *pi, u8 new_conf)
32 {
33 	int ret = 0;
34 
35 	if (pi->conf == new_conf)
36 		return 0;
37 
38 	ret = i2c_smbus_write_byte_data(pi->client, PI3USB30532_CONF, new_conf);
39 	if (ret) {
40 		dev_err(&pi->client->dev, "Error writing conf: %d\n", ret);
41 		return ret;
42 	}
43 
44 	pi->conf = new_conf;
45 	return 0;
46 }
47 
pi3usb30532_sw_set(struct typec_switch * sw,enum typec_orientation orientation)48 static int pi3usb30532_sw_set(struct typec_switch *sw,
49 			      enum typec_orientation orientation)
50 {
51 	struct pi3usb30532 *pi = typec_switch_get_drvdata(sw);
52 	u8 new_conf;
53 	int ret;
54 
55 	mutex_lock(&pi->lock);
56 	new_conf = pi->conf;
57 
58 	switch (orientation) {
59 	case TYPEC_ORIENTATION_NONE:
60 		new_conf = PI3USB30532_CONF_OPEN;
61 		break;
62 	case TYPEC_ORIENTATION_NORMAL:
63 		new_conf &= ~PI3USB30532_CONF_SWAP;
64 		break;
65 	case TYPEC_ORIENTATION_REVERSE:
66 		new_conf |= PI3USB30532_CONF_SWAP;
67 		break;
68 	}
69 
70 	ret = pi3usb30532_set_conf(pi, new_conf);
71 	mutex_unlock(&pi->lock);
72 
73 	return ret;
74 }
75 
76 static int
pi3usb30532_mux_set(struct typec_mux * mux,struct typec_mux_state * state)77 pi3usb30532_mux_set(struct typec_mux *mux, struct typec_mux_state *state)
78 {
79 	struct pi3usb30532 *pi = typec_mux_get_drvdata(mux);
80 	u8 new_conf;
81 	int ret;
82 
83 	mutex_lock(&pi->lock);
84 	new_conf = pi->conf;
85 
86 	switch (state->mode) {
87 	case TYPEC_STATE_SAFE:
88 		new_conf = (new_conf & PI3USB30532_CONF_SWAP) |
89 			   PI3USB30532_CONF_OPEN;
90 		break;
91 	case TYPEC_STATE_USB:
92 		new_conf = (new_conf & PI3USB30532_CONF_SWAP) |
93 			   PI3USB30532_CONF_USB3;
94 		break;
95 	case TYPEC_DP_STATE_C:
96 	case TYPEC_DP_STATE_E:
97 		new_conf = (new_conf & PI3USB30532_CONF_SWAP) |
98 			   PI3USB30532_CONF_4LANE_DP;
99 		break;
100 	case TYPEC_DP_STATE_D:
101 		new_conf = (new_conf & PI3USB30532_CONF_SWAP) |
102 			   PI3USB30532_CONF_USB3_AND_2LANE_DP;
103 		break;
104 	default:
105 		break;
106 	}
107 
108 	ret = pi3usb30532_set_conf(pi, new_conf);
109 	mutex_unlock(&pi->lock);
110 
111 	return ret;
112 }
113 
pi3usb30532_probe(struct i2c_client * client)114 static int pi3usb30532_probe(struct i2c_client *client)
115 {
116 	struct device *dev = &client->dev;
117 	struct typec_switch_desc sw_desc = { };
118 	struct typec_mux_desc mux_desc = { };
119 	struct pi3usb30532 *pi;
120 	int ret;
121 
122 	pi = devm_kzalloc(dev, sizeof(*pi), GFP_KERNEL);
123 	if (!pi)
124 		return -ENOMEM;
125 
126 	pi->client = client;
127 	mutex_init(&pi->lock);
128 
129 	ret = i2c_smbus_read_byte_data(client, PI3USB30532_CONF);
130 	if (ret < 0) {
131 		dev_err(dev, "Error reading config register %d\n", ret);
132 		return ret;
133 	}
134 	pi->conf = ret;
135 
136 	sw_desc.drvdata = pi;
137 	sw_desc.fwnode = dev->fwnode;
138 	sw_desc.set = pi3usb30532_sw_set;
139 
140 	pi->sw = typec_switch_register(dev, &sw_desc);
141 	if (IS_ERR(pi->sw)) {
142 		dev_err(dev, "Error registering typec switch: %ld\n",
143 			PTR_ERR(pi->sw));
144 		return PTR_ERR(pi->sw);
145 	}
146 
147 	mux_desc.drvdata = pi;
148 	mux_desc.fwnode = dev->fwnode;
149 	mux_desc.set = pi3usb30532_mux_set;
150 
151 	pi->mux = typec_mux_register(dev, &mux_desc);
152 	if (IS_ERR(pi->mux)) {
153 		typec_switch_unregister(pi->sw);
154 		dev_err(dev, "Error registering typec mux: %ld\n",
155 			PTR_ERR(pi->mux));
156 		return PTR_ERR(pi->mux);
157 	}
158 
159 	i2c_set_clientdata(client, pi);
160 	return 0;
161 }
162 
pi3usb30532_remove(struct i2c_client * client)163 static int pi3usb30532_remove(struct i2c_client *client)
164 {
165 	struct pi3usb30532 *pi = i2c_get_clientdata(client);
166 
167 	typec_mux_unregister(pi->mux);
168 	typec_switch_unregister(pi->sw);
169 	return 0;
170 }
171 
172 static const struct i2c_device_id pi3usb30532_table[] = {
173 	{ "pi3usb30532" },
174 	{ }
175 };
176 MODULE_DEVICE_TABLE(i2c, pi3usb30532_table);
177 
178 static struct i2c_driver pi3usb30532_driver = {
179 	.driver = {
180 		.name = "pi3usb30532",
181 	},
182 	.probe_new	= pi3usb30532_probe,
183 	.remove		= pi3usb30532_remove,
184 	.id_table	= pi3usb30532_table,
185 };
186 
187 module_i2c_driver(pi3usb30532_driver);
188 
189 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
190 MODULE_DESCRIPTION("Pericom PI3USB30532 Type-C mux driver");
191 MODULE_LICENSE("GPL");
192