input: rewrite virtio touchscreen / keyboard device

Simplified input processing logics.
Used proper virtio APIs.

Change-Id: I24a8564842fbb0d3833c4c2bf21e658c85c00cb0
Signed-off-by: SeokYeon Hwang <syeon.hwang@samsung.com>

2 files changed, 66 insertions, 113 deletions

diff --git a/drivers/maru/maru_virtio_keyboard.c b/drivers/maru/maru_virtio_keyboard.c
index f318ef153a84..a358493b128f 100644
--- a/drivers/maru/maru_virtio_keyboard.c
+++ b/drivers/maru/maru_virtio_keyboard.c
@@ -4,9 +4,8 @@
  * Copyright (c) 2011 Samsung Electronics Co., Ltd. All rights reserved.
  *
  * Contact:
- *  Kitae Kim <kitae.kim@samsung.com>
+ *  GiWoong Kim <giwoong.kim@samsung.com>
  *  SeokYeon Hwang <syeon.hwang@samsung.com>
- *  YeongKyoon Lee <yeongkyoon.lee@samsung.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -39,16 +38,20 @@
 #include <linux/virtio_ids.h>
 #include <linux/virtio_config.h>
 
+
 MODULE_LICENSE("GPL2");
-MODULE_AUTHOR("Kitae Kim <kt920.kim@samsung.com>");
-MODULE_DESCRIPTION("Emulator Virtio Keyboard Driver");
+MODULE_AUTHOR("SeokYeon Hwangm <syeon.hwang@samsung.com>");
+MODULE_DESCRIPTION("Emulator virtio keyboard driver");
+
 
 #define DRIVER_NAME "virtio-keyboard"
+
 #define VKBD_LOG(log_level, fmt, ...) \
 	printk(log_level "%s: " fmt, DRIVER_NAME, ##__VA_ARGS__)
 
-#define KBD_BUF_SIZE 100
-static int vqidx = 0;
+#define MAX_BUF_COUNT 100
+
+//#define DEBUG
 
 struct EmulKbdEvent
 {
@@ -62,14 +65,12 @@ struct virtio_keyboard
 	struct virtqueue *vq;
 	struct input_dev *idev;
 
-	struct EmulKbdEvent kbdevt[KBD_BUF_SIZE];
-	struct scatterlist sg[KBD_BUF_SIZE];
+	struct scatterlist sg[1];
+	struct EmulKbdEvent evtbuf[MAX_BUF_COUNT];
 
-	struct mutex event_mutex;
+	spinlock_t lock;
 };
 
-struct virtio_keyboard *vkbd;
-
 static struct virtio_device_id id_table[] = {
 	{ VIRTIO_ID_KEYBOARD, VIRTIO_DEV_ANY_ID },
 	{ 0 },
@@ -77,42 +78,36 @@ static struct virtio_device_id id_table[] = {
 
 static void vq_keyboard_handle(struct virtqueue *vq)
 {
-	int err = 0, len = 0;
-	void *data;
-	struct EmulKbdEvent kbdevent;
-
-	VKBD_LOG(KERN_DEBUG, "virtqueue callback.\n");
-	data = virtqueue_get_buf(vq, &len);
-	if (!data) {
-		VKBD_LOG(KERN_ERR, "there is no available buffer.\n");
-		return;
-	}
-
-	VKBD_LOG(KERN_DEBUG, "vqidx: %d\n", vqidx);
-	while (1) {
-		memcpy(&kbdevent, &vkbd->kbdevt[vqidx], sizeof(kbdevent));
-#if 1
-		if (kbdevent.code == 0) {
-			break;
-		}
+	unsigned int len; /* not used */
+	struct virtio_keyboard *vkbd = vq->vdev->priv;
+	struct EmulKbdEvent *event;
+
+	unsigned long flags;
+	int err;
+
+	spin_lock_irqsave(&vkbd->lock, flags);
+	while ((event = virtqueue_get_buf(vkbd->vq, &len)) != NULL) {
+		spin_unlock_irqrestore(&vkbd->lock, flags);
+#ifdef DEBUG
+        printk(KERN_ERR "keyboard code = %d, value = %d\n", event->code,
+                event->value);
 #endif
-		/* how to get keycode and value. */
-		input_event(vkbd->idev, EV_KEY, kbdevent.code, kbdevent.value);
+		input_event(vkbd->idev, EV_KEY, event->code, event->value);
 		input_sync(vkbd->idev);
-		printk(KERN_ERR "input_event code = %d, value = %d\n", kbdevent.code, kbdevent.value);
-		memset(&vkbd->kbdevt[vqidx], 0x00, sizeof(kbdevent));
-		vqidx++;
-		if (vqidx == KBD_BUF_SIZE) {
-			vqidx = 0;
+
+		// add new buffer
+		spin_lock_irqsave(&vkbd->lock, flags);
+		sg_init_one(vkbd->sg, event, sizeof(*event));
+		err = virtqueue_add_inbuf(vkbd->vq, vkbd->sg,
+				1, event, GFP_ATOMIC);
+
+		if (err < 0) {
+			printk(KERN_ERR "failed to add buffer!\n");
 		}
 	}
-	err = virtqueue_add_inbuf(vq, vkbd->sg, KBD_BUF_SIZE, (void *)vkbd->kbdevt, GFP_ATOMIC);
-	if (err < 0) {
-		VKBD_LOG(KERN_ERR, "failed to add buffer to virtqueue.\n");
-		return;
-	}
 
 	virtqueue_kick(vkbd->vq);
+	spin_unlock_irqrestore(&vkbd->lock, flags);
 }
 
 static int input_keyboard_open(struct input_dev *dev)
@@ -126,42 +121,22 @@ static void input_keyboard_close(struct input_dev *dev)
 	VKBD_LOG(KERN_DEBUG, "input_keyboard_close\n");
 }
 
-#if 0
-static int virtio_keyboard_open(struct inode *inode, struct file *file)
-{
-	VKBD_LOG(KERN_DEBUG, "opened.\n");
-	return 0;
-}
-
-static int virtio_keyboard_release(struct inode *inode, struct file *file)
-{
-	VKBD_LOG(KERN_DEBUG, "closed\n");
-	return 0;
-}
-
-struct file_operations virtio_keyboard_fops = {
-	.owner   = THIS_MODULE,
-	.open	= virtio_keyboard_open,
-	.release = virtio_keyboard_release,
-};
-#endif
-
 static int virtio_keyboard_probe(struct virtio_device *vdev)
 {
 	int ret = 0;
 	int index = 0;
+	int err = 0;
+	unsigned long flags;
+	struct virtio_keyboard *vkbd;
 
 	VKBD_LOG(KERN_INFO, "driver is probed\n");
-	vqidx = 0;
 
-	vdev->priv = vkbd = kmalloc(sizeof(struct virtio_keyboard), GFP_KERNEL);
+	vdev->priv = vkbd = kzalloc(sizeof(struct virtio_keyboard), GFP_KERNEL);
 	if (!vkbd) {
 		return -ENOMEM;
 	}
-	memset(&vkbd->kbdevt, 0x00, sizeof(vkbd->kbdevt));
 
 	vkbd->vdev = vdev;
-	mutex_init(&vkbd->event_mutex);
 
 	vkbd->vq = virtio_find_single_vq(vkbd->vdev, vq_keyboard_handle, "virtio-keyboard-vq");
 	if (IS_ERR(vkbd->vq)) {
@@ -171,20 +146,6 @@ static int virtio_keyboard_probe(struct virtio_device *vdev)
 		return ret;
 	}
 
-	for (; index < KBD_BUF_SIZE; index++) {
-		sg_set_buf(&vkbd->sg[index],
-				&vkbd->kbdevt[index],
-				sizeof(struct EmulKbdEvent));
-	}
-
-	ret = virtqueue_add_inbuf(vkbd->vq, vkbd->sg, KBD_BUF_SIZE, (void *)vkbd->kbdevt, GFP_ATOMIC);
-	if (ret < 0) {
-		VKBD_LOG(KERN_ERR, "failed to add buffer to virtqueue.\n");
-		kfree(vkbd);
-		vdev->priv = NULL;
-		return ret;
-	}
-
 	/* register for input device */
 	vkbd->idev = input_allocate_device();
 	if (!vkbd->idev) {
@@ -229,11 +190,22 @@ static int virtio_keyboard_probe(struct virtio_device *vdev)
 		return ret;
 	}
 
-	for (; index < KBD_BUF_SIZE; index++) {
-		sg_set_buf(&vkbd->sg[index],
-				&vkbd->kbdevt[index],
-				sizeof(struct EmulKbdEvent));
+	spin_lock_irqsave(&vkbd->lock, flags);
+	for (index = 0; index < MAX_BUF_COUNT; index++) {
+		sg_init_one(vkbd->sg, &vkbd->evtbuf[index], sizeof(&vkbd->evtbuf[index]));
+
+		err = virtqueue_add_inbuf(vkbd->vq, vkbd->sg,
+				1, &vkbd->evtbuf[index], GFP_ATOMIC);
+
+		if (err < 0) {
+			printk(KERN_ERR "failed to add buffer\n");
+
+			kfree(vkbd);
+			vdev->priv = NULL;
+			return err;
+		}
 	}
+	spin_unlock_irqrestore(&vkbd->lock, flags);
 
 	virtqueue_kick(vkbd->vq);
 
@@ -242,6 +214,8 @@ static int virtio_keyboard_probe(struct virtio_device *vdev)
 
 static void virtio_keyboard_remove(struct virtio_device *vdev)
 {
+	struct virtio_keyboard *vkbd = vdev->priv;
+
 	VKBD_LOG(KERN_INFO, "driver is removed.\n");
 	if (!vkbd) {
 		VKBD_LOG(KERN_ERR, "vkbd is NULL.\n");
diff --git a/drivers/maru/maru_virtio_touchscreen.c b/drivers/maru/maru_virtio_touchscreen.c
index ef77bccf111f..5aa04f87e551 100644
--- a/drivers/maru/maru_virtio_touchscreen.c
+++ b/drivers/maru/maru_virtio_touchscreen.c
@@ -40,9 +40,10 @@
 #include <linux/virtio_config.h>
 #include <linux/kthread.h>
 
+
 MODULE_LICENSE("GPL2");
-MODULE_AUTHOR("GiWoong Kim <giwoong.kim@samsung.com>");
-MODULE_DESCRIPTION("Emulator Virtio Touchscreen driver");
+MODULE_AUTHOR("SeokYeon Hwangm <syeon.hwang@samsung.com>");
+MODULE_DESCRIPTION("Emulator virtio touchscreen driver");
 
 
 #define DEVICE_NAME "virtio-touchscreen"
@@ -52,7 +53,7 @@ MODULE_DESCRIPTION("Emulator Virtio Touchscreen driver");
 
 #define MAX_BUF_COUNT MAX_TRKID
 
-//#define DEBUG_TS
+//#define DEBUG
 
 /* This structure must match the qemu definitions */
 struct touch_event
@@ -92,18 +93,13 @@ static void vq_touchscreen_callback(struct virtqueue *vq)
 	unsigned long flags;
 	int err;
 
-#ifdef DEBUG_TS
-	printk(KERN_INFO "vq touchscreen callback\n");
-#endif
-
 	spin_lock_irqsave(&vt->lock, flags);
 	while ((event = virtqueue_get_buf(vt->vq, &len)) != NULL) {
 		spin_unlock_irqrestore(&vt->lock, flags);
-#ifdef DEBUG_TS
-		printk(KERN_INFO "touch x=%d, y=%d, z=%d, state=%d, len=%d\n",
+#ifdef DEBUG
+		printk(KERN_INFO "touchscreen x=%d, y=%d, z=%d, state=%d, len=%d\n",
 				event->x, event->y, event->z, event->state, len);
 #endif
-
 		finger_id = event->z;
 
 		if (finger_id < MAX_TRKID) {
@@ -137,23 +133,12 @@ static void vq_touchscreen_callback(struct virtqueue *vq)
 		if (err < 0) {
 			printk(KERN_ERR "failed to add buffer!\n");
 		}
-	};
+	}
+
 	virtqueue_kick(vt->vq);
 	spin_unlock_irqrestore(&vt->lock, flags);
 }
 
-static int virtio_touchscreen_open(struct inode *inode, struct file *file)
-{
-	printk(KERN_INFO "virtio touchscreen device is opened\n");
-	return 0;
-}
-
-static int virtio_touchscreen_release(struct inode *inode, struct file *file)
-{
-	printk(KERN_INFO "virtio touchscreen device is closed\n");
-	return 0;
-}
-
 static int input_touchscreen_open(struct input_dev *dev)
 {
 	printk(KERN_INFO "input touchscreen device is opened\n");
@@ -165,13 +150,8 @@ static void input_touchscreen_close(struct input_dev *dev)
 	printk(KERN_INFO "input touchscreen device is closed\n");
 }
 
-struct file_operations virtio_touchscreen_fops = {
-	.owner   = THIS_MODULE,
-	.open    = virtio_touchscreen_open,
-	.release = virtio_touchscreen_release,
-};
-
 extern char *saved_command_line;
+
 #define VM_RESOLUTION_KEY "vm_resolution="
 
 static int virtio_touchscreen_probe(struct virtio_device *vdev)
@@ -309,7 +289,6 @@ static int virtio_touchscreen_probe(struct virtio_device *vdev)
 	spin_unlock_irqrestore(&vt->lock, flags);
 
 	virtqueue_kick(vt->vq);
-	index = 0;
 
 	return 0;
 }