--- /dev/null
+/*
+ * Maru Virtio Rotary Device Driver
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd. All rights reserved.
+ *
+ * Contact:
+ * Jinhyung Jo <jinhyung.jo@samsung.com>
+ * Sangho Park <sangho1206.park@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributors:
+ * - S-Core Co., Ltd
+ *
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/input.h>
+#include <linux/miscdevice.h>
+#include <linux/slab.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+
+MODULE_LICENSE("GPL2");
+MODULE_AUTHOR("Jinhyung Jo <jinhyung.jo@samsung.com>");
+MODULE_DESCRIPTION("Emulator Virtio Rotary Driver");
+
+#define DRIVER_NAME "virtio-rotary"
+#define VR_LOG(log_level, fmt, ...) \
+ printk(log_level "%s: " fmt, DRIVER_NAME, ##__VA_ARGS__)
+
+#define ROTARY_BUF_SIZE 512
+static int vqidx;
+
+struct rotary_event {
+ int32_t delta;
+ int32_t type;
+};
+
+struct virtio_rotary {
+ struct virtio_device *vdev;
+ struct virtqueue *vq;
+ struct input_dev *idev;
+
+ struct rotary_event event[ROTARY_BUF_SIZE];
+ struct scatterlist sg[ROTARY_BUF_SIZE];
+
+ struct mutex mutex;
+};
+
+struct virtio_rotary *vrtr;
+
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_ROTARY, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static void vq_rotary_handler(struct virtqueue *vq)
+{
+ int err = 0, len = 0;
+ void *data;
+ struct rotary_event event;
+
+ data = virtqueue_get_buf(vq, &len);
+ if (!data) {
+ VR_LOG(KERN_ERR, "there is no available buffer\n");
+ return;
+ }
+
+ while (1) {
+ memcpy(&event,
+ &vrtr->event[vqidx],
+ sizeof(struct rotary_event));
+ if (event.delta == 0)
+ break;
+ VR_LOG(KERN_DEBUG,
+ "rotary event: vqidx(%d), delta(%d), type(%d)\n",
+ vqidx, event.delta, event.type);
+ input_report_rel(vrtr->idev, REL_X, event.delta);
+ input_report_rel(vrtr->idev, REL_Y, 0);
+ input_sync(vrtr->idev);
+ memset(&vrtr->event[vqidx],
+ 0x00,
+ sizeof(struct rotary_event));
+ vqidx++;
+ if (vqidx == ROTARY_BUF_SIZE)
+ vqidx = 0;
+ }
+ err = virtqueue_add_inbuf(vq,
+ vrtr->sg,
+ ROTARY_BUF_SIZE,
+ (void *)ROTARY_BUF_SIZE,
+ GFP_ATOMIC);
+ if (err < 0) {
+ VR_LOG(KERN_ERR, "failed to add buffer to virtqueue\n");
+ return;
+ }
+
+ virtqueue_kick(vrtr->vq);
+}
+
+static int input_rotary_open(struct input_dev *dev)
+{
+ VR_LOG(KERN_DEBUG, "input_rotary_open\n");
+ return 0;
+}
+
+static void input_rotary_close(struct input_dev *dev)
+{
+ VR_LOG(KERN_DEBUG, "input_rotary_close\n");
+}
+
+static int virtio_rotary_probe(struct virtio_device *vdev)
+{
+ int ret = 0;
+ int index = 0;
+
+ if (vrtr) {
+ VR_LOG(KERN_ERR, "driver is already exist\n");
+ return -EINVAL;
+ }
+
+ vqidx = 0;
+ vdev->priv = vrtr = kzalloc(sizeof(struct virtio_rotary), GFP_KERNEL);
+ if (!vrtr)
+ return -ENOMEM;
+
+ vrtr->vdev = vdev;
+ mutex_init(&vrtr->mutex);
+
+ vrtr->vq = virtio_find_single_vq(vrtr->vdev,
+ vq_rotary_handler,
+ "maru-rotary-vq");
+ if (IS_ERR(vrtr->vq)) {
+ ret = PTR_ERR(vrtr->vq);
+ kfree(vrtr);
+ vdev->priv = NULL;
+ return ret;
+ }
+
+ for (index = 0; index < ROTARY_BUF_SIZE; index++) {
+ sg_init_one(&vrtr->sg[index],
+ &vrtr->event[index],
+ sizeof(struct rotary_event));
+ }
+ ret = virtqueue_add_inbuf(vrtr->vq,
+ vrtr->sg,
+ ROTARY_BUF_SIZE,
+ (void *)ROTARY_BUF_SIZE,
+ GFP_ATOMIC);
+
+ /* register for input device */
+ vrtr->idev = input_allocate_device();
+ if (!vrtr->idev) {
+ VR_LOG(KERN_ERR, "failed to allocate a input device\n");
+ kfree(vrtr);
+ vdev->priv = NULL;
+ return -ENOMEM;
+ }
+
+ vrtr->idev->name = DRIVER_NAME;
+ vrtr->idev->dev.parent = &vdev->dev;
+ vrtr->idev->id.vendor = 0x0001;
+ vrtr->idev->id.product = 0x0001;
+ vrtr->idev->id.version = 0x0100;
+
+ input_set_drvdata(vrtr->idev, vrtr);
+ vrtr->idev->open = input_rotary_open;
+ vrtr->idev->close = input_rotary_close;
+
+ __set_bit(EV_REL, vrtr->idev->evbit);
+ __set_bit(EV_KEY, vrtr->idev->evbit);
+ __set_bit(REL_X, vrtr->idev->relbit);
+ __set_bit(REL_Y, vrtr->idev->relbit);
+ __set_bit(BTN_LEFT, vrtr->idev->keybit);
+
+ input_set_capability(vrtr->idev, EV_REL, REL_X);
+ input_set_capability(vrtr->idev, EV_REL, REL_Y);
+ input_set_capability(vrtr->idev, EV_REL, REL_Z);
+
+ ret = input_register_device(vrtr->idev);
+ if (ret) {
+ VR_LOG(KERN_ERR, "failed to register a input device\n");
+ input_free_device(vrtr->idev);
+ kfree(vrtr);
+ vdev->priv = NULL;
+ return ret;
+ }
+
+ virtqueue_kick(vrtr->vq);
+ VR_LOG(KERN_INFO, "driver probe done\n");
+
+ return 0;
+}
+
+static void virtio_rotary_remove(struct virtio_device *vdev)
+{
+ if (!vrtr) {
+ VR_LOG(KERN_ERR, "rotary instance is NULL\n");
+ return;
+ }
+
+ vdev->config->reset(vdev);
+ vdev->config->del_vqs(vdev);
+
+ input_unregister_device(vrtr->idev);
+
+ kfree(vrtr);
+ vrtr = NULL;
+ VR_LOG(KERN_INFO, "driver is removed\n");
+}
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+
+static struct virtio_driver virtio_rotary_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .owner = THIS_MODULE,
+ },
+ .id_table = id_table,
+ .probe = virtio_rotary_probe,
+ .remove = virtio_rotary_remove,
+#if 0
+#ifdef CONFIG_PM
+ .freeze = virtio_rotary_freeze,
+ .restore = virtio_rotary_restore,
+#endif
+#endif
+};
+
+static int __init virtio_rotary_init(void)
+{
+ VR_LOG(KERN_INFO, "driver is initialized\n");
+ return register_virtio_driver(&virtio_rotary_driver);
+}
+
+static void __exit virtio_rotary_exit(void)
+{
+ VR_LOG(KERN_INFO, "driver is destroyed\n");
+ unregister_virtio_driver(&virtio_rotary_driver);
+}
+
+module_init(virtio_rotary_init);
+module_exit(virtio_rotary_exit);
projects / sdk / emulator / emulator-kernel.git / commitdiff