1 /* 2 * HID over I2C Open Firmware Subclass 3 * 4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com> 5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France 6 * Copyright (c) 2012 Red Hat, Inc 7 * 8 * This code was forked out of the core code, which was partly based on 9 * "USB HID support for Linux": 10 * 11 * Copyright (c) 1999 Andreas Gal 12 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz> 13 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc 14 * Copyright (c) 2007-2008 Oliver Neukum 15 * Copyright (c) 2006-2010 Jiri Kosina 16 * 17 * This file is subject to the terms and conditions of the GNU General Public 18 * License. See the file COPYING in the main directory of this archive for 19 * more details. 20 */ 21 22 #include <linux/delay.h> 23 #include <linux/device.h> 24 #include <linux/i2c.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/of.h> 28 #include <linux/pm.h> 29 #include <linux/regulator/consumer.h> 30 31 #include "i2c-hid.h" 32 33 struct i2c_hid_of { 34 struct i2chid_ops ops; 35 36 struct i2c_client *client; 37 struct regulator_bulk_data supplies[2]; 38 int post_power_delay_ms; 39 }; 40 41 static int i2c_hid_of_power_up(struct i2chid_ops *ops) 42 { 43 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops); 44 struct device *dev = &ihid_of->client->dev; 45 int ret; 46 47 ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies), 48 ihid_of->supplies); 49 if (ret) { 50 dev_warn(dev, "Failed to enable supplies: %d\n", ret); 51 return ret; 52 } 53 54 if (ihid_of->post_power_delay_ms) 55 msleep(ihid_of->post_power_delay_ms); 56 57 return 0; 58 } 59 60 static void i2c_hid_of_power_down(struct i2chid_ops *ops) 61 { 62 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops); 63 64 regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies), 65 ihid_of->supplies); 66 } 67 68 static int i2c_hid_of_probe(struct i2c_client *client, 69 const struct i2c_device_id *dev_id) 70 { 71 struct device *dev = &client->dev; 72 struct i2c_hid_of *ihid_of; 73 u16 hid_descriptor_address; 74 int ret; 75 u32 val; 76 77 ihid_of = devm_kzalloc(&client->dev, sizeof(*ihid_of), GFP_KERNEL); 78 if (!ihid_of) 79 return -ENOMEM; 80 81 ihid_of->ops.power_up = i2c_hid_of_power_up; 82 ihid_of->ops.power_down = i2c_hid_of_power_down; 83 84 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val); 85 if (ret) { 86 dev_err(&client->dev, "HID register address not provided\n"); 87 return -ENODEV; 88 } 89 if (val >> 16) { 90 dev_err(&client->dev, "Bad HID register address: 0x%08x\n", 91 val); 92 return -EINVAL; 93 } 94 hid_descriptor_address = val; 95 96 if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms", 97 &val)) 98 ihid_of->post_power_delay_ms = val; 99 100 ihid_of->supplies[0].supply = "vdd"; 101 ihid_of->supplies[1].supply = "vddl"; 102 ret = devm_regulator_bulk_get(&client->dev, 103 ARRAY_SIZE(ihid_of->supplies), 104 ihid_of->supplies); 105 if (ret) 106 return ret; 107 108 return i2c_hid_core_probe(client, &ihid_of->ops, 109 hid_descriptor_address); 110 } 111 112 static const struct of_device_id i2c_hid_of_match[] = { 113 { .compatible = "hid-over-i2c" }, 114 {}, 115 }; 116 MODULE_DEVICE_TABLE(of, i2c_hid_of_match); 117 118 static const struct i2c_device_id i2c_hid_of_id_table[] = { 119 { "hid", 0 }, 120 { "hid-over-i2c", 0 }, 121 { }, 122 }; 123 MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table); 124 125 static struct i2c_driver i2c_hid_of_driver = { 126 .driver = { 127 .name = "i2c_hid_of", 128 .pm = &i2c_hid_core_pm, 129 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 130 .of_match_table = of_match_ptr(i2c_hid_of_match), 131 }, 132 133 .probe = i2c_hid_of_probe, 134 .remove = i2c_hid_core_remove, 135 .shutdown = i2c_hid_core_shutdown, 136 .id_table = i2c_hid_of_id_table, 137 }; 138 139 module_i2c_driver(i2c_hid_of_driver); 140 141 MODULE_DESCRIPTION("HID over I2C OF driver"); 142 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>"); 143 MODULE_LICENSE("GPL"); 144