Input: matrix-keypad - add function to build device keymap

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

1 files changed, 32 insertions, 0 deletions

diff --git a/include/linux/input/matrix_keypad.h b/include/linux/input/matrix_keypad.h
index 15d5903af2dd..b3cd42d50e16 100644
--- a/include/linux/input/matrix_keypad.h
+++ b/include/linux/input/matrix_keypad.h
@@ -63,4 +63,36 @@ struct matrix_keypad_platform_data {
         bool            wakeup;
 };
 
+/**
+ * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
+ * @keymap_data: keymap supplied by the platform code
+ * @row_shift: number of bits to shift row value by to advance to the next
+ * line in the keymap
+ * @keymap: expanded version of keymap that is suitable for use by
+ * matrix keyboad driver
+ * @keybit: pointer to bitmap of keys supported by input device
+ *
+ * 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.
+ */
+static inline void
+matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
+                           unsigned int row_shift,
+                           unsigned short *keymap, unsigned long *keybit)
+{
+        int i;
+
+        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);
+
+                keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
+                __set_bit(code, keybit);
+        }
+        __clear_bit(KEY_RESERVED, keybit);
+}
+
 #endif /* _MATRIX_KEYPAD_H */