1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2021 Oleh Kravchenko <oleg@kaa.org.ua> 4 * 5 * SparkFun Qwiic Joystick 6 * Product page:https://www.sparkfun.com/products/15168 7 * Firmware and hardware sources:https://github.com/sparkfun/Qwiic_Joystick 8 */ 9 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 28 struct qwiic_jsk { 29 char phys[32]; 30 struct input_dev *dev; 31 struct i2c_client *client; 32 }; 33 34 struct qwiic_ver { 35 u8 major; 36 u8 minor; 37 }; 38 39 struct qwiic_data { 40 __be16 x; 41 __be16 y; 42 u8 thumb; 43 }; 44 45 static 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 62 static 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 121 static const struct of_device_id of_qwiic_match[] = { 122 { .compatible = "sparkfun,qwiic-joystick", }, 123 { }, 124 }; 125 MODULE_DEVICE_TABLE(of, of_qwiic_match); 126 #endif /* CONFIG_OF */ 127 128 static const struct i2c_device_id qwiic_id_table[] = { 129 { KBUILD_MODNAME }, 130 { } 131 }; 132 MODULE_DEVICE_TABLE(i2c, qwiic_id_table); 133 134 static 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 = qwiic_probe, 141 }; 142 module_i2c_driver(qwiic_driver); 143 144 MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>"); 145 MODULE_DESCRIPTION("SparkFun Qwiic Joystick driver"); 146 MODULE_LICENSE("GPL v2"); 147