xref: /openbmc/linux/drivers/hid/hid-icade.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  ION iCade input driver
4  *
5  *  Copyright (c) 2012 Bastien Nocera <hadess@hadess.net>
6  *  Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
7  */
8 
9 /*
10  */
11 
12 #include <linux/device.h>
13 #include <linux/hid.h>
14 #include <linux/module.h>
15 
16 #include "hid-ids.h"
17 
18 /*
19  *   ↑      A C Y L
20  *  ← →
21  *   ↓      B X Z R
22  *
23  *
24  *  UP ON,OFF  = w,e
25  *  RT ON,OFF  = d,c
26  *  DN ON,OFF  = x,z
27  *  LT ON,OFF  = a,q
28  *  A  ON,OFF  = y,t
29  *  B  ON,OFF  = h,r
30  *  C  ON,OFF  = u,f
31  *  X  ON,OFF  = j,n
32  *  Y  ON,OFF  = i,m
33  *  Z  ON,OFF  = k,p
34  *  L  ON,OFF  = o,g
35  *  R  ON,OFF  = l,v
36  */
37 
38 /* The translation code uses HID usage instead of input layer
39  * keys. This code generates a lookup table that makes
40  * translation quick.
41  *
42  * #include <linux/input.h>
43  * #include <stdio.h>
44  * #include <assert.h>
45  *
46  * #define unk     KEY_UNKNOWN
47  *
48  * < copy of hid_keyboard[] from hid-input.c >
49  *
50  * struct icade_key_translation {
51  *     int         from;
52  *     const char *to;
53  *     int         press;
54  * };
55  *
56  * static const struct icade_key_translation icade_keys[] = {
57  *    { KEY_W,        "KEY_UP",         1 },
58  *    { KEY_E,        "KEY_UP",         0 },
59  *    { KEY_D,        "KEY_RIGHT",      1 },
60  *    { KEY_C,        "KEY_RIGHT",      0 },
61  *    { KEY_X,        "KEY_DOWN",       1 },
62  *    { KEY_Z,        "KEY_DOWN",       0 },
63  *    { KEY_A,        "KEY_LEFT",       1 },
64  *    { KEY_Q,        "KEY_LEFT",       0 },
65  *    { KEY_Y,        "BTN_A",          1 },
66  *    { KEY_T,        "BTN_A",          0 },
67  *    { KEY_H,        "BTN_B",          1 },
68  *    { KEY_R,        "BTN_B",          0 },
69  *    { KEY_U,        "BTN_C",          1 },
70  *    { KEY_F,        "BTN_C",          0 },
71  *    { KEY_J,        "BTN_X",          1 },
72  *    { KEY_N,        "BTN_X",          0 },
73  *    { KEY_I,        "BTN_Y",          1 },
74  *    { KEY_M,        "BTN_Y",          0 },
75  *    { KEY_K,        "BTN_Z",          1 },
76  *    { KEY_P,        "BTN_Z",          0 },
77  *    { KEY_O,        "BTN_THUMBL",     1 },
78  *    { KEY_G,        "BTN_THUMBL",     0 },
79  *    { KEY_L,        "BTN_THUMBR",     1 },
80  *    { KEY_V,        "BTN_THUMBR",     0 },
81  *
82  *    { }
83  * };
84  *
85  * static int
86  * usage_for_key (int key)
87  * {
88  *     int i;
89  *     for (i = 0; i < 256; i++) {
90  *     if (hid_keyboard[i] == key)
91  *         return i;
92  *     }
93  *     assert(0);
94  * }
95  *
96  * int main (int argc, char **argv)
97  * {
98  *     const struct icade_key_translation *trans;
99  *     int max_usage = 0;
100  *
101  *     for (trans = icade_keys; trans->from; trans++) {
102  *         int usage = usage_for_key (trans->from);
103  *         max_usage = usage > max_usage ? usage : max_usage;
104  *     }
105  *
106  *     printf ("#define ICADE_MAX_USAGE %d\n\n", max_usage);
107  *     printf ("struct icade_key {\n");
108  *     printf ("\tu16 to;\n");
109  *     printf ("\tu8 press:1;\n");
110  *     printf ("};\n\n");
111  *     printf ("static const struct icade_key "
112  *             "icade_usage_table[%d] = {\n", max_usage + 1);
113  *     for (trans = icade_keys; trans->from; trans++) {
114  *         printf ("\t[%d] = { %s, %d },\n",
115  *                 usage_for_key (trans->from), trans->to, trans->press);
116  *     }
117  *     printf ("};\n");
118  *
119  *     return 0;
120  * }
121  */
122 
123 #define ICADE_MAX_USAGE 29
124 
125 struct icade_key {
126 	u16 to;
127 	u8 press:1;
128 };
129 
130 static const struct icade_key icade_usage_table[30] = {
131 	[26] = { KEY_UP, 1 },
132 	[8] = { KEY_UP, 0 },
133 	[7] = { KEY_RIGHT, 1 },
134 	[6] = { KEY_RIGHT, 0 },
135 	[27] = { KEY_DOWN, 1 },
136 	[29] = { KEY_DOWN, 0 },
137 	[4] = { KEY_LEFT, 1 },
138 	[20] = { KEY_LEFT, 0 },
139 	[28] = { BTN_A, 1 },
140 	[23] = { BTN_A, 0 },
141 	[11] = { BTN_B, 1 },
142 	[21] = { BTN_B, 0 },
143 	[24] = { BTN_C, 1 },
144 	[9] = { BTN_C, 0 },
145 	[13] = { BTN_X, 1 },
146 	[17] = { BTN_X, 0 },
147 	[12] = { BTN_Y, 1 },
148 	[16] = { BTN_Y, 0 },
149 	[14] = { BTN_Z, 1 },
150 	[19] = { BTN_Z, 0 },
151 	[18] = { BTN_THUMBL, 1 },
152 	[10] = { BTN_THUMBL, 0 },
153 	[15] = { BTN_THUMBR, 1 },
154 	[25] = { BTN_THUMBR, 0 },
155 };
156 
157 static const struct icade_key *icade_find_translation(u16 from)
158 {
159 	if (from > ICADE_MAX_USAGE)
160 		return NULL;
161 	return &icade_usage_table[from];
162 }
163 
164 static int icade_event(struct hid_device *hdev, struct hid_field *field,
165 		struct hid_usage *usage, __s32 value)
166 {
167 	const struct icade_key *trans;
168 
169 	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput ||
170 			!usage->type)
171 		return 0;
172 
173 	/* We ignore the fake key up, and act only on key down */
174 	if (!value)
175 		return 1;
176 
177 	trans = icade_find_translation(usage->hid & HID_USAGE);
178 
179 	if (!trans)
180 		return 1;
181 
182 	input_event(field->hidinput->input, usage->type,
183 			trans->to, trans->press);
184 
185 	return 1;
186 }
187 
188 static int icade_input_mapping(struct hid_device *hdev, struct hid_input *hi,
189 		struct hid_field *field, struct hid_usage *usage,
190 		unsigned long **bit, int *max)
191 {
192 	const struct icade_key *trans;
193 
194 	if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD) {
195 		trans = icade_find_translation(usage->hid & HID_USAGE);
196 
197 		if (!trans)
198 			return -1;
199 
200 		hid_map_usage(hi, usage, bit, max, EV_KEY, trans->to);
201 		set_bit(trans->to, hi->input->keybit);
202 
203 		return 1;
204 	}
205 
206 	/* ignore others */
207 	return -1;
208 
209 }
210 
211 static int icade_input_mapped(struct hid_device *hdev, struct hid_input *hi,
212 		struct hid_field *field, struct hid_usage *usage,
213 		unsigned long **bit, int *max)
214 {
215 	if (usage->type == EV_KEY)
216 		set_bit(usage->type, hi->input->evbit);
217 
218 	return -1;
219 }
220 
221 static const struct hid_device_id icade_devices[] = {
222 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ION, USB_DEVICE_ID_ICADE) },
223 
224 	{ }
225 };
226 MODULE_DEVICE_TABLE(hid, icade_devices);
227 
228 static struct hid_driver icade_driver = {
229 	.name = "icade",
230 	.id_table = icade_devices,
231 	.event = icade_event,
232 	.input_mapped = icade_input_mapped,
233 	.input_mapping = icade_input_mapping,
234 };
235 module_hid_driver(icade_driver);
236 
237 MODULE_LICENSE("GPL");
238 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
239 MODULE_DESCRIPTION("ION iCade input driver");
240