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