Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 220 insertions, 0 deletions

diff --git a/kernel/arch/powerpc/platforms/powermac/backlight.c b/kernel/arch/powerpc/platforms/powermac/backlight.c
new file mode 100644
index 000000000..a00096b1c
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/powermac/backlight.c
@@ -0,0 +1,220 @@
+/*
+ * Miscellaneous procedures for dealing with the PowerMac hardware.
+ * Contains support for the backlight.
+ *
+ *   Copyright (C) 2000 Benjamin Herrenschmidt
+ *   Copyright (C) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/adb.h>
+#include <linux/pmu.h>
+#include <linux/atomic.h>
+#include <linux/export.h>
+#include <asm/prom.h>
+#include <asm/backlight.h>
+
+#define OLD_BACKLIGHT_MAX 15
+
+static void pmac_backlight_key_worker(struct work_struct *work);
+static void pmac_backlight_set_legacy_worker(struct work_struct *work);
+
+static DECLARE_WORK(pmac_backlight_key_work, pmac_backlight_key_worker);
+static DECLARE_WORK(pmac_backlight_set_legacy_work, pmac_backlight_set_legacy_worker);
+
+/* Although these variables are used in interrupt context, it makes no sense to
+ * protect them. No user is able to produce enough key events per second and
+ * notice the errors that might happen.
+ */
+static int pmac_backlight_key_queued;
+static int pmac_backlight_set_legacy_queued;
+
+/* The via-pmu code allows the backlight to be grabbed, in which case the
+ * in-kernel control of the brightness needs to be disabled. This should
+ * only be used by really old PowerBooks.
+ */
+static atomic_t kernel_backlight_disabled = ATOMIC_INIT(0);
+
+/* Protect the pmac_backlight variable below.
+   You should hold this lock when using the pmac_backlight pointer to
+   prevent its potential removal. */
+DEFINE_MUTEX(pmac_backlight_mutex);
+
+/* Main backlight storage
+ *
+ * Backlight drivers in this variable are required to have the "ops"
+ * attribute set and to have an update_status function.
+ *
+ * We can only store one backlight here, but since Apple laptops have only one
+ * internal display, it doesn't matter. Other backlight drivers can be used
+ * independently.
+ *
+ */
+struct backlight_device *pmac_backlight;
+
+int pmac_has_backlight_type(const char *type)
+{
+	struct device_node* bk_node = of_find_node_by_name(NULL, "backlight");
+
+	if (bk_node) {
+		const char *prop = of_get_property(bk_node,
+				"backlight-control", NULL);
+		if (prop && strncmp(prop, type, strlen(type)) == 0) {
+			of_node_put(bk_node);
+			return 1;
+		}
+		of_node_put(bk_node);
+	}
+
+	return 0;
+}
+
+int pmac_backlight_curve_lookup(struct fb_info *info, int value)
+{
+	int level = (FB_BACKLIGHT_LEVELS - 1);
+
+	if (info && info->bl_dev) {
+		int i, max = 0;
+
+		/* Look for biggest value */
+		for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
+			max = max((int)info->bl_curve[i], max);
+
+		/* Look for nearest value */
+		for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
+			int diff = abs(info->bl_curve[i] - value);
+			if (diff < max) {
+				max = diff;
+				level = i;
+			}
+		}
+
+	}
+
+	return level;
+}
+
+static void pmac_backlight_key_worker(struct work_struct *work)
+{
+	if (atomic_read(&kernel_backlight_disabled))
+		return;
+
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
+		int brightness;
+
+		props = &pmac_backlight->props;
+
+		brightness = props->brightness +
+			((pmac_backlight_key_queued?-1:1) *
+			 (props->max_brightness / 15));
+
+		if (brightness < 0)
+			brightness = 0;
+		else if (brightness > props->max_brightness)
+			brightness = props->max_brightness;
+
+		props->brightness = brightness;
+		backlight_update_status(pmac_backlight);
+	}
+	mutex_unlock(&pmac_backlight_mutex);
+}
+
+/* This function is called in interrupt context */
+void pmac_backlight_key(int direction)
+{
+	if (atomic_read(&kernel_backlight_disabled))
+		return;
+
+	/* we can receive multiple interrupts here, but the scheduled work
+	 * will run only once, with the last value
+	 */
+	pmac_backlight_key_queued = direction;
+	schedule_work(&pmac_backlight_key_work);
+}
+
+static int __pmac_backlight_set_legacy_brightness(int brightness)
+{
+	int error = -ENXIO;
+
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
+
+		props = &pmac_backlight->props;
+		props->brightness = brightness *
+			(props->max_brightness + 1) /
+			(OLD_BACKLIGHT_MAX + 1);
+
+		if (props->brightness > props->max_brightness)
+			props->brightness = props->max_brightness;
+		else if (props->brightness < 0)
+			props->brightness = 0;
+
+		backlight_update_status(pmac_backlight);
+
+		error = 0;
+	}
+	mutex_unlock(&pmac_backlight_mutex);
+
+	return error;
+}
+
+static void pmac_backlight_set_legacy_worker(struct work_struct *work)
+{
+	if (atomic_read(&kernel_backlight_disabled))
+		return;
+
+	__pmac_backlight_set_legacy_brightness(pmac_backlight_set_legacy_queued);
+}
+
+/* This function is called in interrupt context */
+void pmac_backlight_set_legacy_brightness_pmu(int brightness) {
+	if (atomic_read(&kernel_backlight_disabled))
+		return;
+
+	pmac_backlight_set_legacy_queued = brightness;
+	schedule_work(&pmac_backlight_set_legacy_work);
+}
+
+int pmac_backlight_set_legacy_brightness(int brightness)
+{
+	return __pmac_backlight_set_legacy_brightness(brightness);
+}
+
+int pmac_backlight_get_legacy_brightness()
+{
+	int result = -ENXIO;
+
+	mutex_lock(&pmac_backlight_mutex);
+	if (pmac_backlight) {
+		struct backlight_properties *props;
+
+		props = &pmac_backlight->props;
+
+		result = props->brightness *
+			(OLD_BACKLIGHT_MAX + 1) /
+			(props->max_brightness + 1);
+	}
+	mutex_unlock(&pmac_backlight_mutex);
+
+	return result;
+}
+
+void pmac_backlight_disable()
+{
+	atomic_inc(&kernel_backlight_disabled);
+}
+
+void pmac_backlight_enable()
+{
+	atomic_dec(&kernel_backlight_disabled);
+}
+
+EXPORT_SYMBOL_GPL(pmac_backlight);
+EXPORT_SYMBOL_GPL(pmac_backlight_mutex);
+EXPORT_SYMBOL_GPL(pmac_has_backlight_type);