tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * HID support for Vivaldi Keyboard
4 *
5 * Copyright 2020 Google LLC.
6 * Author: Sean O'Brien <seobrien@chromium.org>
7 */
8
9#include <linux/hid.h>
10#include <linux/module.h>
11
12#define MIN_FN_ROW_KEY 1
13#define MAX_FN_ROW_KEY 24
14#define HID_VD_FN_ROW_PHYSMAP 0x00000001
15#define HID_USAGE_FN_ROW_PHYSMAP (HID_UP_GOOGLEVENDOR | HID_VD_FN_ROW_PHYSMAP)
16
17static struct hid_driver hid_vivaldi;
18
19struct vivaldi_data {
20 u32 function_row_physmap[MAX_FN_ROW_KEY - MIN_FN_ROW_KEY + 1];
21 int max_function_row_key;
22};
23
24static ssize_t function_row_physmap_show(struct device *dev,
25 struct device_attribute *attr,
26 char *buf)
27{
28 struct hid_device *hdev = to_hid_device(dev);
29 struct vivaldi_data *drvdata = hid_get_drvdata(hdev);
30 ssize_t size = 0;
31 int i;
32
33 if (!drvdata->max_function_row_key)
34 return 0;
35
36 for (i = 0; i < drvdata->max_function_row_key; i++)
37 size += sprintf(buf + size, "%02X ",
38 drvdata->function_row_physmap[i]);
39 size += sprintf(buf + size, "\n");
40 return size;
41}
42
43DEVICE_ATTR_RO(function_row_physmap);
44static struct attribute *sysfs_attrs[] = {
45 &dev_attr_function_row_physmap.attr,
46 NULL
47};
48
49static const struct attribute_group input_attribute_group = {
50 .attrs = sysfs_attrs
51};
52
53static int vivaldi_probe(struct hid_device *hdev,
54 const struct hid_device_id *id)
55{
56 struct vivaldi_data *drvdata;
57 int ret;
58
59 drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
60 if (!drvdata)
61 return -ENOMEM;
62
63 hid_set_drvdata(hdev, drvdata);
64
65 ret = hid_parse(hdev);
66 if (ret)
67 return ret;
68
69 return hid_hw_start(hdev, HID_CONNECT_DEFAULT);
70}
71
72static void vivaldi_feature_mapping(struct hid_device *hdev,
73 struct hid_field *field,
74 struct hid_usage *usage)
75{
76 struct vivaldi_data *drvdata = hid_get_drvdata(hdev);
77 int fn_key;
78 int ret;
79 u32 report_len;
80 u8 *buf;
81
82 if (field->logical != HID_USAGE_FN_ROW_PHYSMAP ||
83 (usage->hid & HID_USAGE_PAGE) != HID_UP_ORDINAL)
84 return;
85
86 fn_key = (usage->hid & HID_USAGE);
87 if (fn_key < MIN_FN_ROW_KEY || fn_key > MAX_FN_ROW_KEY)
88 return;
89 if (fn_key > drvdata->max_function_row_key)
90 drvdata->max_function_row_key = fn_key;
91
92 buf = hid_alloc_report_buf(field->report, GFP_KERNEL);
93 if (!buf)
94 return;
95
96 report_len = hid_report_len(field->report);
97 ret = hid_hw_raw_request(hdev, field->report->id, buf,
98 report_len, HID_FEATURE_REPORT,
99 HID_REQ_GET_REPORT);
100 if (ret < 0) {
101 dev_warn(&hdev->dev, "failed to fetch feature %d\n",
102 field->report->id);
103 goto out;
104 }
105
106 ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, buf,
107 report_len, 0);
108 if (ret) {
109 dev_warn(&hdev->dev, "failed to report feature %d\n",
110 field->report->id);
111 goto out;
112 }
113
114 drvdata->function_row_physmap[fn_key - MIN_FN_ROW_KEY] =
115 field->value[usage->usage_index];
116
117out:
118 kfree(buf);
119}
120
121static int vivaldi_input_configured(struct hid_device *hdev,
122 struct hid_input *hidinput)
123{
124 return sysfs_create_group(&hdev->dev.kobj, &input_attribute_group);
125}
126
127static const struct hid_device_id vivaldi_table[] = {
128 { HID_DEVICE(HID_BUS_ANY, HID_GROUP_VIVALDI, HID_ANY_ID,
129 HID_ANY_ID) },
130 { }
131};
132
133MODULE_DEVICE_TABLE(hid, vivaldi_table);
134
135static struct hid_driver hid_vivaldi = {
136 .name = "hid-vivaldi",
137 .id_table = vivaldi_table,
138 .probe = vivaldi_probe,
139 .feature_mapping = vivaldi_feature_mapping,
140 .input_configured = vivaldi_input_configured,
141};
142
143module_hid_driver(hid_vivaldi);
144
145MODULE_AUTHOR("Sean O'Brien");
146MODULE_DESCRIPTION("HID vivaldi driver");
147MODULE_LICENSE("GPL");