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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/input/touchscreen/of_touchscreen.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
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>
Diffstat (limited to 'kernel/drivers/input/touchscreen/of_touchscreen.c')
-rw-r--r--kernel/drivers/input/touchscreen/of_touchscreen.c87
1 files changed, 87 insertions, 0 deletions
diff --git a/kernel/drivers/input/touchscreen/of_touchscreen.c b/kernel/drivers/input/touchscreen/of_touchscreen.c
new file mode 100644
index 000000000..b82b5207c
--- /dev/null
+++ b/kernel/drivers/input/touchscreen/of_touchscreen.c
@@ -0,0 +1,87 @@
+/*
+ * Generic DT helper functions for touchscreen devices
+ *
+ * Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/of.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+
+static u32 of_get_optional_u32(struct device_node *np,
+ const char *property)
+{
+ u32 val = 0;
+
+ of_property_read_u32(np, property, &val);
+
+ return val;
+}
+
+static void touchscreen_set_params(struct input_dev *dev,
+ unsigned long axis,
+ int max, int fuzz)
+{
+ struct input_absinfo *absinfo;
+
+ if (!test_bit(axis, dev->absbit)) {
+ /*
+ * Emit a warning only if the axis is not a multitouch
+ * axis, which might not be set by the driver.
+ */
+ if (!input_is_mt_axis(axis))
+ dev_warn(&dev->dev,
+ "DT specifies parameters but the axis is not set up\n");
+ return;
+ }
+
+ absinfo = &dev->absinfo[axis];
+ absinfo->maximum = max;
+ absinfo->fuzz = fuzz;
+}
+
+/**
+ * touchscreen_parse_of_params - parse common touchscreen DT properties
+ * @dev: device that should be parsed
+ *
+ * This function parses common DT properties for touchscreens and setups the
+ * input device accordingly. The function keeps previously setuped default
+ * values if no value is specified via DT.
+ */
+void touchscreen_parse_of_params(struct input_dev *dev)
+{
+ struct device_node *np = dev->dev.parent->of_node;
+ u32 maximum, fuzz;
+
+ input_alloc_absinfo(dev);
+ if (!dev->absinfo)
+ return;
+
+ maximum = of_get_optional_u32(np, "touchscreen-size-x");
+ fuzz = of_get_optional_u32(np, "touchscreen-fuzz-x");
+ if (maximum || fuzz) {
+ touchscreen_set_params(dev, ABS_X, maximum, fuzz);
+ touchscreen_set_params(dev, ABS_MT_POSITION_X, maximum, fuzz);
+ }
+
+ maximum = of_get_optional_u32(np, "touchscreen-size-y");
+ fuzz = of_get_optional_u32(np, "touchscreen-fuzz-y");
+ if (maximum || fuzz) {
+ touchscreen_set_params(dev, ABS_Y, maximum, fuzz);
+ touchscreen_set_params(dev, ABS_MT_POSITION_Y, maximum, fuzz);
+ }
+
+ maximum = of_get_optional_u32(np, "touchscreen-max-pressure");
+ fuzz = of_get_optional_u32(np, "touchscreen-fuzz-pressure");
+ if (maximum || fuzz) {
+ touchscreen_set_params(dev, ABS_PRESSURE, maximum, fuzz);
+ touchscreen_set_params(dev, ABS_MT_PRESSURE, maximum, fuzz);
+ }
+}
+EXPORT_SYMBOL(touchscreen_parse_of_params);