Input: matrix-keymap - uninline and prepare for device tree support

Change matrix-keymap helper to be out-of-line, like sparse keymap,
allow the helper perform basic keymap validation and return errors,
and prepare for device tree support.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/matrix-keymap.c

@@ -0,0 +1,142 @@
+/*
+ * 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/kernel.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/of.h>
+#include <linux/export.h>
+#include <linux/gfp.h>
+#include <linux/slab.h>
+#include <linux/input/matrix_keypad.h>
+
+
+/**
+ * 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.
+ */
+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;
+
+	input_dev->keycode = keymap;
+	input_dev->keycodesize = sizeof(*keymap);
+	input_dev->keycodemax = rows << row_shift;
+
+	__set_bit(EV_KEY, input_dev->evbit);
+
+	for (i = 0; i < keymap_data->keymap_size; i++) {
+		unsigned int key = keymap_data->keymap[i];
+		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 %d (row: %d, col: %d, rows: %d, cols: %d)\n",
+				__func__, i, row, col, rows, cols);
+			return -EINVAL;
+		}
+
+		keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
+		__set_bit(code, input_dev->keybit);
+	}
+	__clear_bit(KEY_RESERVED, input_dev->keybit);
+
+	return 0;
+}
+EXPORT_SYMBOL(matrix_keypad_build_keymap);
+
+#ifdef CONFIG_OF
+struct matrix_keymap_data *
+matrix_keyboard_of_fill_keymap(struct device_node *np,
+			       const char *propname)
+{
+	struct matrix_keymap_data *kd;
+	u32 *keymap;
+	int proplen, i;
+	const __be32 *prop;
+
+	if (!np)
+		return NULL;
+
+	if (!propname)
+		propname = "linux,keymap";
+
+	prop = of_get_property(np, propname, &proplen);
+	if (!prop)
+		return NULL;
+
+	if (proplen % sizeof(u32)) {
+		pr_warn("Malformed keymap property %s in %s\n",
+			propname, np->full_name);
+		return NULL;
+	}
+
+	kd = kzalloc(sizeof(*kd), GFP_KERNEL);
+	if (!kd)
+		return NULL;
+
+	kd->keymap = keymap = kzalloc(proplen, GFP_KERNEL);
+	if (!kd->keymap) {
+		kfree(kd);
+		return NULL;
+	}
+
+	kd->keymap_size = proplen / sizeof(u32);
+
+	for (i = 0; i < kd->keymap_size; i++) {
+		u32 tmp = be32_to_cpup(prop + i);
+		int key_code, row, col;
+
+		row = (tmp >> 24) & 0xff;
+		col = (tmp >> 16) & 0xff;
+		key_code = tmp & 0xffff;
+		keymap[i] = KEY(row, col, key_code);
+	}
+
+	return kd;
+}
+EXPORT_SYMBOL_GPL(matrix_keyboard_of_fill_keymap);
+
+void matrix_keyboard_of_free_keymap(const struct matrix_keymap_data *kd)
+{
+	if (kd) {
+		kfree(kd->keymap);
+		kfree(kd);
+	}
+}
+EXPORT_SYMBOL_GPL(matrix_keyboard_of_free_keymap);
+#endif