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10#include <linux/bits.h>
11#include <linux/i2c.h>
12#include <linux/input.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15
16#define DRV_NAME "qwiic-joystick"
17
18#define QWIIC_JSK_REG_VERS 1
19#define QWIIC_JSK_REG_DATA 3
20
21#define QWIIC_JSK_MAX_AXIS GENMASK(9, 0)
22#define QWIIC_JSK_FUZZ 2
23#define QWIIC_JSK_FLAT 2
24#define QWIIC_JSK_POLL_INTERVAL 16
25#define QWIIC_JSK_POLL_MIN 8
26#define QWIIC_JSK_POLL_MAX 32
27
28struct qwiic_jsk {
29 char phys[32];
30 struct input_dev *dev;
31 struct i2c_client *client;
32};
33
34struct qwiic_ver {
35 u8 major;
36 u8 minor;
37};
38
39struct qwiic_data {
40 __be16 x;
41 __be16 y;
42 u8 thumb;
43};
44
45static void qwiic_poll(struct input_dev *input)
46{
47 struct qwiic_jsk *priv = input_get_drvdata(input);
48 struct qwiic_data data;
49 int err;
50
51 err = i2c_smbus_read_i2c_block_data(priv->client, QWIIC_JSK_REG_DATA,
52 sizeof(data), (u8 *)&data);
53 if (err != sizeof(data))
54 return;
55
56 input_report_abs(input, ABS_X, be16_to_cpu(data.x) >> 6);
57 input_report_abs(input, ABS_Y, be16_to_cpu(data.y) >> 6);
58 input_report_key(input, BTN_THUMBL, !data.thumb);
59 input_sync(input);
60}
61
62static int qwiic_probe(struct i2c_client *client)
63{
64 struct qwiic_jsk *priv;
65 struct qwiic_ver vers;
66 int err;
67
68 err = i2c_smbus_read_i2c_block_data(client, QWIIC_JSK_REG_VERS,
69 sizeof(vers), (u8 *)&vers);
70 if (err < 0)
71 return err;
72 if (err != sizeof(vers))
73 return -EIO;
74
75 dev_dbg(&client->dev, "SparkFun Qwiic Joystick, FW: %u.%u\n",
76 vers.major, vers.minor);
77
78 priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
79 if (!priv)
80 return -ENOMEM;
81
82 priv->client = client;
83 snprintf(priv->phys, sizeof(priv->phys),
84 "i2c/%s", dev_name(&client->dev));
85 i2c_set_clientdata(client, priv);
86
87 priv->dev = devm_input_allocate_device(&client->dev);
88 if (!priv->dev)
89 return -ENOMEM;
90
91 priv->dev->id.bustype = BUS_I2C;
92 priv->dev->name = "SparkFun Qwiic Joystick";
93 priv->dev->phys = priv->phys;
94 input_set_drvdata(priv->dev, priv);
95
96 input_set_abs_params(priv->dev, ABS_X, 0, QWIIC_JSK_MAX_AXIS,
97 QWIIC_JSK_FUZZ, QWIIC_JSK_FLAT);
98 input_set_abs_params(priv->dev, ABS_Y, 0, QWIIC_JSK_MAX_AXIS,
99 QWIIC_JSK_FUZZ, QWIIC_JSK_FLAT);
100 input_set_capability(priv->dev, EV_KEY, BTN_THUMBL);
101
102 err = input_setup_polling(priv->dev, qwiic_poll);
103 if (err) {
104 dev_err(&client->dev, "failed to set up polling: %d\n", err);
105 return err;
106 }
107 input_set_poll_interval(priv->dev, QWIIC_JSK_POLL_INTERVAL);
108 input_set_min_poll_interval(priv->dev, QWIIC_JSK_POLL_MIN);
109 input_set_max_poll_interval(priv->dev, QWIIC_JSK_POLL_MAX);
110
111 err = input_register_device(priv->dev);
112 if (err) {
113 dev_err(&client->dev, "failed to register joystick: %d\n", err);
114 return err;
115 }
116
117 return 0;
118}
119
120#ifdef CONFIG_OF
121static const struct of_device_id of_qwiic_match[] = {
122 { .compatible = "sparkfun,qwiic-joystick", },
123 { },
124};
125MODULE_DEVICE_TABLE(of, of_qwiic_match);
126#endif
127
128static const struct i2c_device_id qwiic_id_table[] = {
129 { KBUILD_MODNAME, 0 },
130 { },
131};
132MODULE_DEVICE_TABLE(i2c, qwiic_id_table);
133
134static struct i2c_driver qwiic_driver = {
135 .driver = {
136 .name = DRV_NAME,
137 .of_match_table = of_match_ptr(of_qwiic_match),
138 },
139 .id_table = qwiic_id_table,
140 .probe_new = qwiic_probe,
141};
142module_i2c_driver(qwiic_driver);
143
144MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
145MODULE_DESCRIPTION("SparkFun Qwiic Joystick driver");
146MODULE_LICENSE("GPL v2");
147
