xref: /openbmc/linux/drivers/hid/hid-icade.c (revision ae213c44)
1 /*
2  *  ION iCade input driver
3  *
4  *  Copyright (c) 2012 Bastien Nocera <hadess@hadess.net>
5  *  Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
6  */
7 
8 /*
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the Free
11  * Software Foundation; either version 2 of the License, or (at your option)
12  * any later version.
13  */
14 
15 #include <linux/device.h>
16 #include <linux/hid.h>
17 #include <linux/module.h>
18 
19 #include "hid-ids.h"
20 
21 /*
22  *   ↑      A C Y L
23  *  ← →
24  *   ↓      B X Z R
25  *
26  *
27  *  UP ON,OFF  = w,e
28  *  RT ON,OFF  = d,c
29  *  DN ON,OFF  = x,z
30  *  LT ON,OFF  = a,q
31  *  A  ON,OFF  = y,t
32  *  B  ON,OFF  = h,r
33  *  C  ON,OFF  = u,f
34  *  X  ON,OFF  = j,n
35  *  Y  ON,OFF  = i,m
36  *  Z  ON,OFF  = k,p
37  *  L  ON,OFF  = o,g
38  *  R  ON,OFF  = l,v
39  */
40 
41 /* The translation code uses HID usage instead of input layer
42  * keys. This code generates a lookup table that makes
43  * translation quick.
44  *
45  * #include <linux/input.h>
46  * #include <stdio.h>
47  * #include <assert.h>
48  *
49  * #define unk     KEY_UNKNOWN
50  *
51  * < copy of hid_keyboard[] from hid-input.c >
52  *
53  * struct icade_key_translation {
54  *     int         from;
55  *     const char *to;
56  *     int         press;
57  * };
58  *
59  * static const struct icade_key_translation icade_keys[] = {
60  *    { KEY_W,        "KEY_UP",         1 },
61  *    { KEY_E,        "KEY_UP",         0 },
62  *    { KEY_D,        "KEY_RIGHT",      1 },
63  *    { KEY_C,        "KEY_RIGHT",      0 },
64  *    { KEY_X,        "KEY_DOWN",       1 },
65  *    { KEY_Z,        "KEY_DOWN",       0 },
66  *    { KEY_A,        "KEY_LEFT",       1 },
67  *    { KEY_Q,        "KEY_LEFT",       0 },
68  *    { KEY_Y,        "BTN_A",          1 },
69  *    { KEY_T,        "BTN_A",          0 },
70  *    { KEY_H,        "BTN_B",          1 },
71  *    { KEY_R,        "BTN_B",          0 },
72  *    { KEY_U,        "BTN_C",          1 },
73  *    { KEY_F,        "BTN_C",          0 },
74  *    { KEY_J,        "BTN_X",          1 },
75  *    { KEY_N,        "BTN_X",          0 },
76  *    { KEY_I,        "BTN_Y",          1 },
77  *    { KEY_M,        "BTN_Y",          0 },
78  *    { KEY_K,        "BTN_Z",          1 },
79  *    { KEY_P,        "BTN_Z",          0 },
80  *    { KEY_O,        "BTN_THUMBL",     1 },
81  *    { KEY_G,        "BTN_THUMBL",     0 },
82  *    { KEY_L,        "BTN_THUMBR",     1 },
83  *    { KEY_V,        "BTN_THUMBR",     0 },
84  *
85  *    { }
86  * };
87  *
88  * static int
89  * usage_for_key (int key)
90  * {
91  *     int i;
92  *     for (i = 0; i < 256; i++) {
93  *     if (hid_keyboard[i] == key)
94  *         return i;
95  *     }
96  *     assert(0);
97  * }
98  *
99  * int main (int argc, char **argv)
100  * {
101  *     const struct icade_key_translation *trans;
102  *     int max_usage = 0;
103  *
104  *     for (trans = icade_keys; trans->from; trans++) {
105  *         int usage = usage_for_key (trans->from);
106  *         max_usage = usage > max_usage ? usage : max_usage;
107  *     }
108  *
109  *     printf ("#define ICADE_MAX_USAGE %d\n\n", max_usage);
110  *     printf ("struct icade_key {\n");
111  *     printf ("\tu16 to;\n");
112  *     printf ("\tu8 press:1;\n");
113  *     printf ("};\n\n");
114  *     printf ("static const struct icade_key "
115  *             "icade_usage_table[%d] = {\n", max_usage + 1);
116  *     for (trans = icade_keys; trans->from; trans++) {
117  *         printf ("\t[%d] = { %s, %d },\n",
118  *                 usage_for_key (trans->from), trans->to, trans->press);
119  *     }
120  *     printf ("};\n");
121  *
122  *     return 0;
123  * }
124  */
125 
126 #define ICADE_MAX_USAGE 29
127 
128 struct icade_key {
129 	u16 to;
130 	u8 press:1;
131 };
132 
133 static const struct icade_key icade_usage_table[30] = {
134 	[26] = { KEY_UP, 1 },
135 	[8] = { KEY_UP, 0 },
136 	[7] = { KEY_RIGHT, 1 },
137 	[6] = { KEY_RIGHT, 0 },
138 	[27] = { KEY_DOWN, 1 },
139 	[29] = { KEY_DOWN, 0 },
140 	[4] = { KEY_LEFT, 1 },
141 	[20] = { KEY_LEFT, 0 },
142 	[28] = { BTN_A, 1 },
143 	[23] = { BTN_A, 0 },
144 	[11] = { BTN_B, 1 },
145 	[21] = { BTN_B, 0 },
146 	[24] = { BTN_C, 1 },
147 	[9] = { BTN_C, 0 },
148 	[13] = { BTN_X, 1 },
149 	[17] = { BTN_X, 0 },
150 	[12] = { BTN_Y, 1 },
151 	[16] = { BTN_Y, 0 },
152 	[14] = { BTN_Z, 1 },
153 	[19] = { BTN_Z, 0 },
154 	[18] = { BTN_THUMBL, 1 },
155 	[10] = { BTN_THUMBL, 0 },
156 	[15] = { BTN_THUMBR, 1 },
157 	[25] = { BTN_THUMBR, 0 },
158 };
159 
160 static const struct icade_key *icade_find_translation(u16 from)
161 {
162 	if (from > ICADE_MAX_USAGE)
163 		return NULL;
164 	return &icade_usage_table[from];
165 }
166 
167 static int icade_event(struct hid_device *hdev, struct hid_field *field,
168 		struct hid_usage *usage, __s32 value)
169 {
170 	const struct icade_key *trans;
171 
172 	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput ||
173 			!usage->type)
174 		return 0;
175 
176 	/* We ignore the fake key up, and act only on key down */
177 	if (!value)
178 		return 1;
179 
180 	trans = icade_find_translation(usage->hid & HID_USAGE);
181 
182 	if (!trans)
183 		return 1;
184 
185 	input_event(field->hidinput->input, usage->type,
186 			trans->to, trans->press);
187 
188 	return 1;
189 }
190 
191 static int icade_input_mapping(struct hid_device *hdev, struct hid_input *hi,
192 		struct hid_field *field, struct hid_usage *usage,
193 		unsigned long **bit, int *max)
194 {
195 	const struct icade_key *trans;
196 
197 	if ((usage->hid & HID_USAGE_PAGE) == HID_UP_KEYBOARD) {
198 		trans = icade_find_translation(usage->hid & HID_USAGE);
199 
200 		if (!trans)
201 			return -1;
202 
203 		hid_map_usage(hi, usage, bit, max, EV_KEY, trans->to);
204 		set_bit(trans->to, hi->input->keybit);
205 
206 		return 1;
207 	}
208 
209 	/* ignore others */
210 	return -1;
211 
212 }
213 
214 static int icade_input_mapped(struct hid_device *hdev, struct hid_input *hi,
215 		struct hid_field *field, struct hid_usage *usage,
216 		unsigned long **bit, int *max)
217 {
218 	if (usage->type == EV_KEY)
219 		set_bit(usage->type, hi->input->evbit);
220 
221 	return -1;
222 }
223 
224 static const struct hid_device_id icade_devices[] = {
225 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ION, USB_DEVICE_ID_ICADE) },
226 
227 	{ }
228 };
229 MODULE_DEVICE_TABLE(hid, icade_devices);
230 
231 static struct hid_driver icade_driver = {
232 	.name = "icade",
233 	.id_table = icade_devices,
234 	.event = icade_event,
235 	.input_mapped = icade_input_mapped,
236 	.input_mapping = icade_input_mapping,
237 };
238 module_hid_driver(icade_driver);
239 
240 MODULE_LICENSE("GPL");
241 MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
242 MODULE_DESCRIPTION("ION iCade input driver");
243