video: tegra: Add control device to dc extension driver

This device exposes control over everything that's not specific to one
of T20's two display controllers.  It supports:
- output devices
- event delivery
- hotplug events

bug 818525

Change-Id: I3a46f1dddc483b08ed3ee91a4f9c64111c1fd7eb
Signed-off-by: Robert Morell <rmorell@nvidia.com>
Reviewed-on: http://git-master/r/40520
Reviewed-by: Varun Colbert <vcolbert@nvidia.com>
Tested-by: Varun Colbert <vcolbert@nvidia.com>

1 files changed, 220 insertions, 0 deletions

diff --git a/drivers/video/tegra/dc/ext/control.c b/drivers/video/tegra/dc/ext/control.c
new file mode 100644
index 000000000000..6cc2f9a7d54a
--- /dev/null
+++ b/drivers/video/tegra/dc/ext/control.c
@@ -0,0 +1,220 @@
+/*
+ * drivers/video/tegra/dc/ext/control.c
+ *
+ * Copyright (C) 2011, NVIDIA Corporation
+ *
+ * Author: Robert Morell <rmorell@nvidia.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.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+#include "tegra_dc_ext_priv.h"
+
+static struct tegra_dc_ext_control g_control;
+
+int tegra_dc_ext_process_hotplug(int output)
+{
+	return tegra_dc_ext_queue_hotplug(&g_control, output);
+}
+
+static int
+get_output_properties(struct tegra_dc_ext_control_output_properties *properties)
+{
+	/* TODO: this should be more dynamic */
+	if (properties->handle > 2)
+		return -EINVAL;
+
+	switch (properties->handle) {
+	case 0:
+		properties->type = TEGRA_DC_EXT_LVDS;
+		properties->connected = 1;
+		break;
+	case 1:
+		properties->type = TEGRA_DC_EXT_HDMI;
+		properties->connected = 1;
+		break;
+	default:
+		return -EINVAL;
+	}
+	properties->associated_head = properties->handle;
+
+	return 0;
+}
+
+static int get_output_edid(struct tegra_dc_ext_control_output_edid *edid)
+{
+	/* XXX implement me */
+	return -ENOTSUPP;
+}
+
+static int set_event_mask(struct tegra_dc_ext_control_user *user, u32 mask)
+{
+	struct list_head *list, *tmp;
+
+	if (mask & ~TEGRA_DC_EXT_EVENT_MASK_ALL)
+		return -EINVAL;
+
+	mutex_lock(&user->lock);
+
+	user->event_mask = mask;
+
+	list_for_each_safe(list, tmp, &user->event_list) {
+		struct tegra_dc_ext_event_list *ev_list;
+		ev_list = list_entry(list, struct tegra_dc_ext_event_list,
+			list);
+		if (!(mask & ev_list->event.type)) {
+			list_del(list);
+			kfree(ev_list);
+		}
+	}
+	mutex_unlock(&user->lock);
+
+	return 0;
+}
+
+static long tegra_dc_ext_control_ioctl(struct file *filp, unsigned int cmd,
+				       unsigned long arg)
+{
+	void __user *user_arg = (void __user *)arg;
+	struct tegra_dc_ext_control_user *user = filp->private_data;
+
+	switch (cmd) {
+	case TEGRA_DC_EXT_CONTROL_GET_NUM_OUTPUTS:
+	{
+		u32 num = tegra_dc_ext_get_num_outputs();
+
+		if (copy_to_user(user_arg, &num, sizeof(num)))
+			return -EFAULT;
+
+		return 0;
+	}
+	case TEGRA_DC_EXT_CONTROL_GET_OUTPUT_PROPERTIES:
+	{
+		struct tegra_dc_ext_control_output_properties args;
+		int ret;
+
+		if (copy_from_user(&args, user_arg, sizeof(args)))
+			return -EFAULT;
+
+		ret = get_output_properties(&args);
+
+		if (copy_to_user(user_arg, &args, sizeof(args)))
+			return -EFAULT;
+
+		return ret;
+	}
+	case TEGRA_DC_EXT_CONTROL_GET_OUTPUT_EDID:
+	{
+		struct tegra_dc_ext_control_output_edid args;
+		int ret;
+
+		if (copy_from_user(&args, user_arg, sizeof(args)))
+			return -EFAULT;
+
+		ret = get_output_edid(&args);
+
+		if (copy_to_user(user_arg, &args, sizeof(args)))
+			return -EFAULT;
+
+		return ret;
+	}
+	case TEGRA_DC_EXT_CONTROL_SET_EVENT_MASK:
+		return set_event_mask(user, (u32) arg);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int tegra_dc_ext_control_open(struct inode *inode, struct file *filp)
+{
+	struct tegra_dc_ext_control_user *user;
+	struct tegra_dc_ext_control *control;
+
+	user = kzalloc(sizeof(*user), GFP_KERNEL);
+	if (!user)
+		return -ENOMEM;
+
+	control = container_of(inode->i_cdev, struct tegra_dc_ext_control,
+		cdev);
+	user->control = control;;
+
+	INIT_LIST_HEAD(&user->event_list);
+	mutex_init(&user->lock);
+
+	filp->private_data = user;
+
+	mutex_lock(&control->lock);
+	list_add(&user->list, &control->users);
+	mutex_unlock(&control->lock);
+
+	return 0;
+}
+
+static int tegra_dc_ext_control_release(struct inode *inode, struct file *filp)
+{
+	struct tegra_dc_ext_control_user *user = filp->private_data;
+	struct tegra_dc_ext_control *control = user->control;
+
+	/* This will free any pending events for this user */
+	set_event_mask(user, 0);
+
+	mutex_lock(&control->lock);
+	list_del(&user->list);
+	mutex_unlock(&control->lock);
+
+	kfree(user);
+
+	return 0;
+}
+
+static const struct file_operations tegra_dc_ext_event_devops = {
+	.owner =		THIS_MODULE,
+	.open =			tegra_dc_ext_control_open,
+	.release =		tegra_dc_ext_control_release,
+	.read =			tegra_dc_ext_event_read,
+	.unlocked_ioctl =	tegra_dc_ext_control_ioctl,
+};
+
+int tegra_dc_ext_control_init(void)
+{
+	struct tegra_dc_ext_control *control = &g_control;
+	int ret;
+
+	cdev_init(&control->cdev, &tegra_dc_ext_event_devops);
+	control->cdev.owner = THIS_MODULE;
+	ret = cdev_add(&control->cdev, tegra_dc_ext_devno, 1);
+	if (ret)
+		return ret;
+
+	control->dev = device_create(tegra_dc_ext_class,
+				     NULL,
+				     tegra_dc_ext_devno,
+				     NULL,
+				     "tegra_dc_ctrl");
+	if (IS_ERR(control->dev)) {
+		ret = PTR_ERR(control->dev);
+		cdev_del(&control->cdev);
+	}
+
+	mutex_init(&control->lock);
+
+	INIT_LIST_HEAD(&control->users);
+
+	return ret;
+}