1
2#include <linux/module.h>
3#include <linux/virtio.h>
4#include <linux/virtio_config.h>
5#include <linux/input.h>
6#include <linux/slab.h>
7
8#include <uapi/linux/virtio_ids.h>
9#include <uapi/linux/virtio_input.h>
10
11struct virtio_input {
12 struct virtio_device *vdev;
13 struct input_dev *idev;
14 char name[64];
15 char serial[64];
16 char phys[64];
17 struct virtqueue *evt, *sts;
18 struct virtio_input_event evts[64];
19 spinlock_t lock;
20 bool ready;
21};
22
23static void virtinput_queue_evtbuf(struct virtio_input *vi,
24 struct virtio_input_event *evtbuf)
25{
26 struct scatterlist sg[1];
27
28 sg_init_one(sg, evtbuf, sizeof(*evtbuf));
29 virtqueue_add_inbuf(vi->evt, sg, 1, evtbuf, GFP_ATOMIC);
30}
31
32static void virtinput_recv_events(struct virtqueue *vq)
33{
34 struct virtio_input *vi = vq->vdev->priv;
35 struct virtio_input_event *event;
36 unsigned long flags;
37 unsigned int len;
38
39 spin_lock_irqsave(&vi->lock, flags);
40 if (vi->ready) {
41 while ((event = virtqueue_get_buf(vi->evt, &len)) != NULL) {
42 spin_unlock_irqrestore(&vi->lock, flags);
43 input_event(vi->idev,
44 le16_to_cpu(event->type),
45 le16_to_cpu(event->code),
46 le32_to_cpu(event->value));
47 spin_lock_irqsave(&vi->lock, flags);
48 virtinput_queue_evtbuf(vi, event);
49 }
50 virtqueue_kick(vq);
51 }
52 spin_unlock_irqrestore(&vi->lock, flags);
53}
54
55
56
57
58
59static int virtinput_send_status(struct virtio_input *vi,
60 u16 type, u16 code, s32 value)
61{
62 struct virtio_input_event *stsbuf;
63 struct scatterlist sg[1];
64 unsigned long flags;
65 int rc;
66
67 stsbuf = kzalloc(sizeof(*stsbuf), GFP_ATOMIC);
68 if (!stsbuf)
69 return -ENOMEM;
70
71 stsbuf->type = cpu_to_le16(type);
72 stsbuf->code = cpu_to_le16(code);
73 stsbuf->value = cpu_to_le32(value);
74 sg_init_one(sg, stsbuf, sizeof(*stsbuf));
75
76 spin_lock_irqsave(&vi->lock, flags);
77 if (vi->ready) {
78 rc = virtqueue_add_outbuf(vi->sts, sg, 1, stsbuf, GFP_ATOMIC);
79 virtqueue_kick(vi->sts);
80 } else {
81 rc = -ENODEV;
82 }
83 spin_unlock_irqrestore(&vi->lock, flags);
84
85 if (rc != 0)
86 kfree(stsbuf);
87 return rc;
88}
89
90static void virtinput_recv_status(struct virtqueue *vq)
91{
92 struct virtio_input *vi = vq->vdev->priv;
93 struct virtio_input_event *stsbuf;
94 unsigned long flags;
95 unsigned int len;
96
97 spin_lock_irqsave(&vi->lock, flags);
98 while ((stsbuf = virtqueue_get_buf(vi->sts, &len)) != NULL)
99 kfree(stsbuf);
100 spin_unlock_irqrestore(&vi->lock, flags);
101}
102
103static int virtinput_status(struct input_dev *idev, unsigned int type,
104 unsigned int code, int value)
105{
106 struct virtio_input *vi = input_get_drvdata(idev);
107
108 return virtinput_send_status(vi, type, code, value);
109}
110
111static u8 virtinput_cfg_select(struct virtio_input *vi,
112 u8 select, u8 subsel)
113{
114 u8 size;
115
116 virtio_cwrite_le(vi->vdev, struct virtio_input_config, select, &select);
117 virtio_cwrite_le(vi->vdev, struct virtio_input_config, subsel, &subsel);
118 virtio_cread_le(vi->vdev, struct virtio_input_config, size, &size);
119 return size;
120}
121
122static void virtinput_cfg_bits(struct virtio_input *vi, int select, int subsel,
123 unsigned long *bits, unsigned int bitcount)
124{
125 unsigned int bit;
126 u8 *virtio_bits;
127 u8 bytes;
128
129 bytes = virtinput_cfg_select(vi, select, subsel);
130 if (!bytes)
131 return;
132 if (bitcount > bytes * 8)
133 bitcount = bytes * 8;
134
135
136
137
138
139
140 virtio_bits = kzalloc(bytes, GFP_KERNEL);
141 if (!virtio_bits)
142 return;
143 virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config,
144 u.bitmap),
145 virtio_bits, bytes);
146 for (bit = 0; bit < bitcount; bit++) {
147 if (virtio_bits[bit / 8] & (1 << (bit % 8)))
148 __set_bit(bit, bits);
149 }
150 kfree(virtio_bits);
151
152 if (select == VIRTIO_INPUT_CFG_EV_BITS)
153 __set_bit(subsel, vi->idev->evbit);
154}
155
156static void virtinput_cfg_abs(struct virtio_input *vi, int abs)
157{
158 u32 mi, ma, re, fu, fl;
159
160 virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ABS_INFO, abs);
161 virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.min, &mi);
162 virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.max, &ma);
163 virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.res, &re);
164 virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.fuzz, &fu);
165 virtio_cread_le(vi->vdev, struct virtio_input_config, u.abs.flat, &fl);
166 input_set_abs_params(vi->idev, abs, mi, ma, fu, fl);
167 input_abs_set_res(vi->idev, abs, re);
168}
169
170static int virtinput_init_vqs(struct virtio_input *vi)
171{
172 struct virtqueue *vqs[2];
173 vq_callback_t *cbs[] = { virtinput_recv_events,
174 virtinput_recv_status };
175 static const char * const names[] = { "events", "status" };
176 int err;
177
178 err = virtio_find_vqs(vi->vdev, 2, vqs, cbs, names, NULL);
179 if (err)
180 return err;
181 vi->evt = vqs[0];
182 vi->sts = vqs[1];
183
184 return 0;
185}
186
187static void virtinput_fill_evt(struct virtio_input *vi)
188{
189 unsigned long flags;
190 int i, size;
191
192 spin_lock_irqsave(&vi->lock, flags);
193 size = virtqueue_get_vring_size(vi->evt);
194 if (size > ARRAY_SIZE(vi->evts))
195 size = ARRAY_SIZE(vi->evts);
196 for (i = 0; i < size; i++)
197 virtinput_queue_evtbuf(vi, &vi->evts[i]);
198 virtqueue_kick(vi->evt);
199 spin_unlock_irqrestore(&vi->lock, flags);
200}
201
202static int virtinput_probe(struct virtio_device *vdev)
203{
204 struct virtio_input *vi;
205 unsigned long flags;
206 size_t size;
207 int abs, err;
208
209 if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
210 return -ENODEV;
211
212 vi = kzalloc(sizeof(*vi), GFP_KERNEL);
213 if (!vi)
214 return -ENOMEM;
215
216 vdev->priv = vi;
217 vi->vdev = vdev;
218 spin_lock_init(&vi->lock);
219
220 err = virtinput_init_vqs(vi);
221 if (err)
222 goto err_init_vq;
223
224 vi->idev = input_allocate_device();
225 if (!vi->idev) {
226 err = -ENOMEM;
227 goto err_input_alloc;
228 }
229 input_set_drvdata(vi->idev, vi);
230
231 size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_NAME, 0);
232 virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config,
233 u.string),
234 vi->name, min(size, sizeof(vi->name)));
235 size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_SERIAL, 0);
236 virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config,
237 u.string),
238 vi->serial, min(size, sizeof(vi->serial)));
239 snprintf(vi->phys, sizeof(vi->phys),
240 "virtio%d/input0", vdev->index);
241 vi->idev->name = vi->name;
242 vi->idev->phys = vi->phys;
243 vi->idev->uniq = vi->serial;
244
245 size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_DEVIDS, 0);
246 if (size >= sizeof(struct virtio_input_devids)) {
247 virtio_cread_le(vi->vdev, struct virtio_input_config,
248 u.ids.bustype, &vi->idev->id.bustype);
249 virtio_cread_le(vi->vdev, struct virtio_input_config,
250 u.ids.vendor, &vi->idev->id.vendor);
251 virtio_cread_le(vi->vdev, struct virtio_input_config,
252 u.ids.product, &vi->idev->id.product);
253 virtio_cread_le(vi->vdev, struct virtio_input_config,
254 u.ids.version, &vi->idev->id.version);
255 } else {
256 vi->idev->id.bustype = BUS_VIRTUAL;
257 }
258
259 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_PROP_BITS, 0,
260 vi->idev->propbit, INPUT_PROP_CNT);
261 size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REP);
262 if (size)
263 __set_bit(EV_REP, vi->idev->evbit);
264
265 vi->idev->dev.parent = &vdev->dev;
266 vi->idev->event = virtinput_status;
267
268
269 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_KEY,
270 vi->idev->keybit, KEY_CNT);
271 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REL,
272 vi->idev->relbit, REL_CNT);
273 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_ABS,
274 vi->idev->absbit, ABS_CNT);
275 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_MSC,
276 vi->idev->mscbit, MSC_CNT);
277 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SW,
278 vi->idev->swbit, SW_CNT);
279
280
281 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_LED,
282 vi->idev->ledbit, LED_CNT);
283 virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SND,
284 vi->idev->sndbit, SND_CNT);
285
286 if (test_bit(EV_ABS, vi->idev->evbit)) {
287 for (abs = 0; abs < ABS_CNT; abs++) {
288 if (!test_bit(abs, vi->idev->absbit))
289 continue;
290 virtinput_cfg_abs(vi, abs);
291 }
292 }
293
294 virtio_device_ready(vdev);
295 vi->ready = true;
296 err = input_register_device(vi->idev);
297 if (err)
298 goto err_input_register;
299
300 virtinput_fill_evt(vi);
301 return 0;
302
303err_input_register:
304 spin_lock_irqsave(&vi->lock, flags);
305 vi->ready = false;
306 spin_unlock_irqrestore(&vi->lock, flags);
307 input_free_device(vi->idev);
308err_input_alloc:
309 vdev->config->del_vqs(vdev);
310err_init_vq:
311 kfree(vi);
312 return err;
313}
314
315static void virtinput_remove(struct virtio_device *vdev)
316{
317 struct virtio_input *vi = vdev->priv;
318 void *buf;
319 unsigned long flags;
320
321 spin_lock_irqsave(&vi->lock, flags);
322 vi->ready = false;
323 spin_unlock_irqrestore(&vi->lock, flags);
324
325 input_unregister_device(vi->idev);
326 vdev->config->reset(vdev);
327 while ((buf = virtqueue_detach_unused_buf(vi->sts)) != NULL)
328 kfree(buf);
329 vdev->config->del_vqs(vdev);
330 kfree(vi);
331}
332
333#ifdef CONFIG_PM_SLEEP
334static int virtinput_freeze(struct virtio_device *vdev)
335{
336 struct virtio_input *vi = vdev->priv;
337 unsigned long flags;
338
339 spin_lock_irqsave(&vi->lock, flags);
340 vi->ready = false;
341 spin_unlock_irqrestore(&vi->lock, flags);
342
343 vdev->config->del_vqs(vdev);
344 return 0;
345}
346
347static int virtinput_restore(struct virtio_device *vdev)
348{
349 struct virtio_input *vi = vdev->priv;
350 int err;
351
352 err = virtinput_init_vqs(vi);
353 if (err)
354 return err;
355
356 virtio_device_ready(vdev);
357 vi->ready = true;
358 virtinput_fill_evt(vi);
359 return 0;
360}
361#endif
362
363static unsigned int features[] = {
364
365};
366static struct virtio_device_id id_table[] = {
367 { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID },
368 { 0 },
369};
370
371static struct virtio_driver virtio_input_driver = {
372 .driver.name = KBUILD_MODNAME,
373 .driver.owner = THIS_MODULE,
374 .feature_table = features,
375 .feature_table_size = ARRAY_SIZE(features),
376 .id_table = id_table,
377 .probe = virtinput_probe,
378 .remove = virtinput_remove,
379#ifdef CONFIG_PM_SLEEP
380 .freeze = virtinput_freeze,
381 .restore = virtinput_restore,
382#endif
383};
384
385module_virtio_driver(virtio_input_driver);
386MODULE_DEVICE_TABLE(virtio, id_table);
387
388MODULE_LICENSE("GPL");
389MODULE_DESCRIPTION("Virtio input device driver");
390MODULE_AUTHOR("Gerd Hoffmann <kraxel@redhat.com>");
391
