1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/input/matrix-keymap.c b/drivers/input/matrix-keymap.c
new file mode 100644
index 000000000000..443ad64b7f2a
--- /dev/null
+++ b/drivers/input/matrix-keymap.c
@@ -0,0 +1,163 @@
+/*
+ * Helpers for matrix keyboard bindings
+ *
+ * Copyright (C) 2012 Google, Inc
+ *
+ * Author:
+ *	Olof Johansson <olof@lixom.net>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/kernel.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/of.h>
+#include <linux/export.h>
+#include <linux/input/matrix_keypad.h>
+
+static bool matrix_keypad_map_key(struct input_dev *input_dev,
+				  unsigned int rows, unsigned int cols,
+				  unsigned int row_shift, unsigned int key)
+{
+	unsigned short *keymap = input_dev->keycode;
+	unsigned int row = KEY_ROW(key);
+	unsigned int col = KEY_COL(key);
+	unsigned short code = KEY_VAL(key);
+
+	if (row >= rows || col >= cols) {
+		dev_err(input_dev->dev.parent,
+			"%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
+			__func__, key, row, col, rows, cols);
+		return false;
+	}
+
+	keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
+	__set_bit(code, input_dev->keybit);
+
+	return true;
+}
+
+#ifdef CONFIG_OF
+static int matrix_keypad_parse_of_keymap(const char *propname,
+					 unsigned int rows, unsigned int cols,
+					 struct input_dev *input_dev)
+{
+	struct device *dev = input_dev->dev.parent;
+	struct device_node *np = dev->of_node;
+	unsigned int row_shift = get_count_order(cols);
+	unsigned int max_keys = rows << row_shift;
+	unsigned int proplen, i, size;
+	const __be32 *prop;
+
+	if (!np)
+		return -ENOENT;
+
+	if (!propname)
+		propname = "linux,keymap";
+
+	prop = of_get_property(np, propname, &proplen);
+	if (!prop) {
+		dev_err(dev, "OF: %s property not defined in %s\n",
+			propname, np->full_name);
+		return -ENOENT;
+	}
+
+	if (proplen % sizeof(u32)) {
+		dev_err(dev, "OF: Malformed keycode property %s in %s\n",
+			propname, np->full_name);
+		return -EINVAL;
+	}
+
+	size = proplen / sizeof(u32);
+	if (size > max_keys) {
+		dev_err(dev, "OF: %s size overflow\n", propname);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < size; i++) {
+		unsigned int key = be32_to_cpup(prop + i);
+
+		if (!matrix_keypad_map_key(input_dev, rows, cols,
+					   row_shift, key))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+#else
+static int matrix_keypad_parse_of_keymap(const char *propname,
+					 unsigned int rows, unsigned int cols,
+					 struct input_dev *input_dev)
+{
+	return -ENOSYS;
+}
+#endif
+
+/**
+ * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
+ * @keymap_data: keymap supplied by the platform code
+ * @keymap_name: name of device tree property containing keymap (if device
+ *	tree support is enabled).
+ * @rows: number of rows in target keymap array
+ * @cols: number of cols in target keymap array
+ * @keymap: expanded version of keymap that is suitable for use by
+ * matrix keyboard driver
+ * @input_dev: input devices for which we are setting up the keymap
+ *
+ * This function converts platform keymap (encoded with KEY() macro) into
+ * an array of keycodes that is suitable for using in a standard matrix
+ * keyboard driver that uses row and col as indices.
+ *
+ * If @keymap_data is not supplied and device tree support is enabled
+ * it will attempt load the keymap from property specified by @keymap_name
+ * argument (or "linux,keymap" if @keymap_name is %NULL).
+ *
+ * Callers are expected to set up input_dev->dev.parent before calling this
+ * function.
+ */
+int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
+			       const char *keymap_name,
+			       unsigned int rows, unsigned int cols,
+			       unsigned short *keymap,
+			       struct input_dev *input_dev)
+{
+	unsigned int row_shift = get_count_order(cols);
+	int i;
+	int error;
+
+	input_dev->keycode = keymap;
+	input_dev->keycodesize = sizeof(*keymap);
+	input_dev->keycodemax = rows << row_shift;
+
+	__set_bit(EV_KEY, input_dev->evbit);
+
+	if (keymap_data) {
+		for (i = 0; i < keymap_data->keymap_size; i++) {
+			unsigned int key = keymap_data->keymap[i];
+
+			if (!matrix_keypad_map_key(input_dev, rows, cols,
+						   row_shift, key))
+				return -EINVAL;
+		}
+	} else {
+		error = matrix_keypad_parse_of_keymap(keymap_name, rows, cols,
+						      input_dev);
+		if (error)
+			return error;
+	}
+
+	__clear_bit(KEY_RESERVED, input_dev->keybit);
+
+	return 0;
+}
+EXPORT_SYMBOL(matrix_keypad_build_keymap);