Input: touchscreen - broaden use-cases described in comments

Now that the helper functions have been moved to drivers/input/ so
that all input devices may use them, the introductory comments can
be updated to remove any implication that the helper functions are
solely limited to touchscreens.

This patch also scrubs any remaining use of 'DT' since there isn't
any actual dependency on OF. A minor spelling error is resolved as
well ('setups' -> 'sets up').
Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/20210301234928.4298-3-jeff@labundy.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen.c

 // SPDX-License-Identifier: GPL-2.0-only
 /*
- *  Generic DT helper functions for touchscreen devices
+ *  Generic helper functions for touchscreens and other two-dimensional
+ *  pointing devices
  *
  *  Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
  */
@@ -37,7 +38,7 @@ static void touchscreen_set_params(struct input_dev *dev,
 
 	if (!test_bit(axis, dev->absbit)) {
 		dev_warn(&dev->dev,
-			 "DT specifies parameters but the axis %lu is not set up\n",
+			 "Parameters are specified but the axis %lu is not set up\n",
 			 axis);
 		return;
 	}
@@ -49,7 +50,7 @@ static void touchscreen_set_params(struct input_dev *dev,
 }
 
 /**
- * touchscreen_parse_properties - parse common touchscreen DT properties
+ * touchscreen_parse_properties - parse common touchscreen properties
  * @input: input device that should be parsed
  * @multitouch: specifies whether parsed properties should be applied to
  *	single-touch or multi-touch axes
@@ -57,9 +58,9 @@ static void touchscreen_set_params(struct input_dev *dev,
  *	axis swap and invert info for use with touchscreen_report_x_y();
  *	or %NULL
  *
- * This function parses common DT properties for touchscreens and setups the
+ * This function parses common properties for touchscreens and sets up the
  * input device accordingly. The function keeps previously set up default
- * values if no value is specified via DT.
+ * values if no value is specified.
  */
 void touchscreen_parse_properties(struct input_dev *input, bool multitouch,
 				  struct touchscreen_properties *prop)
@@ -203,4 +204,4 @@ void touchscreen_report_pos(struct input_dev *input,
 EXPORT_SYMBOL(touchscreen_report_pos);
 
 MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("Device-tree helpers functions for touchscreen devices");
+MODULE_DESCRIPTION("Helper functions for touchscreens and other devices");