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);