1 // SPDX-License-Identifier: GPL-2.0-only
2 /* MCP23S08 I2C GPIO driver */
3 
4 #include <linux/i2c.h>
5 #include <linux/mod_devicetable.h>
6 #include <linux/module.h>
7 #include <linux/regmap.h>
8 
9 #include "pinctrl-mcp23s08.h"
10 
mcp230xx_probe(struct i2c_client * client)11 static int mcp230xx_probe(struct i2c_client *client)
12 {
13 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
14 	struct device *dev = &client->dev;
15 	unsigned int type = id->driver_data;
16 	struct mcp23s08 *mcp;
17 	int ret;
18 
19 	mcp = devm_kzalloc(dev, sizeof(*mcp), GFP_KERNEL);
20 	if (!mcp)
21 		return -ENOMEM;
22 
23 	switch (type) {
24 	case MCP_TYPE_008:
25 		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x08_regmap);
26 		mcp->reg_shift = 0;
27 		mcp->chip.ngpio = 8;
28 		mcp->chip.label = "mcp23008";
29 		break;
30 
31 	case MCP_TYPE_017:
32 		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x17_regmap);
33 		mcp->reg_shift = 1;
34 		mcp->chip.ngpio = 16;
35 		mcp->chip.label = "mcp23017";
36 		break;
37 
38 	case MCP_TYPE_018:
39 		mcp->regmap = devm_regmap_init_i2c(client, &mcp23x17_regmap);
40 		mcp->reg_shift = 1;
41 		mcp->chip.ngpio = 16;
42 		mcp->chip.label = "mcp23018";
43 		break;
44 
45 	default:
46 		dev_err(dev, "invalid device type (%d)\n", type);
47 		return -EINVAL;
48 	}
49 
50 	if (IS_ERR(mcp->regmap))
51 		return PTR_ERR(mcp->regmap);
52 
53 	mcp->irq = client->irq;
54 	mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
55 
56 	ret = mcp23s08_probe_one(mcp, dev, client->addr, type, -1);
57 	if (ret)
58 		return ret;
59 
60 	i2c_set_clientdata(client, mcp);
61 
62 	return 0;
63 }
64 
65 static const struct i2c_device_id mcp230xx_id[] = {
66 	{ "mcp23008", MCP_TYPE_008 },
67 	{ "mcp23017", MCP_TYPE_017 },
68 	{ "mcp23018", MCP_TYPE_018 },
69 	{ }
70 };
71 MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
72 
73 static const struct of_device_id mcp23s08_i2c_of_match[] = {
74 	{
75 		.compatible = "microchip,mcp23008",
76 		.data = (void *) MCP_TYPE_008,
77 	},
78 	{
79 		.compatible = "microchip,mcp23017",
80 		.data = (void *) MCP_TYPE_017,
81 	},
82 	{
83 		.compatible = "microchip,mcp23018",
84 		.data = (void *) MCP_TYPE_018,
85 	},
86 /* NOTE: The use of the mcp prefix is deprecated and will be removed. */
87 	{
88 		.compatible = "mcp,mcp23008",
89 		.data = (void *) MCP_TYPE_008,
90 	},
91 	{
92 		.compatible = "mcp,mcp23017",
93 		.data = (void *) MCP_TYPE_017,
94 	},
95 	{ }
96 };
97 MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
98 
99 static struct i2c_driver mcp230xx_driver = {
100 	.driver = {
101 		.name	= "mcp230xx",
102 		.of_match_table = mcp23s08_i2c_of_match,
103 	},
104 	.probe_new	= mcp230xx_probe,
105 	.id_table	= mcp230xx_id,
106 };
107 
mcp23s08_i2c_init(void)108 static int __init mcp23s08_i2c_init(void)
109 {
110 	return i2c_add_driver(&mcp230xx_driver);
111 }
112 
113 /*
114  * Register after I²C postcore initcall and before
115  * subsys initcalls that may rely on these GPIOs.
116  */
117 subsys_initcall(mcp23s08_i2c_init);
118 
mcp23s08_i2c_exit(void)119 static void mcp23s08_i2c_exit(void)
120 {
121 	i2c_del_driver(&mcp230xx_driver);
122 }
123 module_exit(mcp23s08_i2c_exit);
124 
125 MODULE_LICENSE("GPL");
126