gpio: add TS-5500 DIO blocks support

Technologic Systems TS-5500 provides digital I/O lines exposed through
pin blocks. On this platform, there are three of them, named DIO1, DIO2
and LCD port, that may be used as a DIO block.

The TS-5500 pin blocks are described in the product's wiki:
http://wiki.embeddedarm.com/wiki/TS-5500#Digital_I.2FO

This driver is not limited to the TS-5500 blocks. It can be extended to
support similar boards pin blocks, such as on the TS-5600.

This patch is the V2 of the previous https://lkml.org/lkml/2012/9/25/671
with corrections suggested by Linus Walleij.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jerome Oufella <jerome.oufella@savoirfairelinux.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/platform_data/gpio-ts5500.h b/include/linux/platform_data/gpio-ts5500.h
new file mode 100644
index 0000000..b10d11c
--- /dev/null
+++ b/include/linux/platform_data/gpio-ts5500.h
@@ -0,0 +1,27 @@
+/*
+ * GPIO (DIO) header for Technologic Systems TS-5500
+ *
+ * Copyright (c) 2012 Savoir-faire Linux Inc.
+ *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _PDATA_GPIO_TS5500_H
+#define _PDATA_GPIO_TS5500_H
+
+/**
+ * struct ts5500_dio_platform_data - TS-5500 pin block configuration
+ * @base:	The GPIO base number to use.
+ * @strap:	The only pin connected to an interrupt in a block is input-only.
+ *		If you need a bidirectional line which can trigger an IRQ, you
+ *		may strap it with an in/out pin. This flag indicates this case.
+ */
+struct ts5500_dio_platform_data {
+	int base;
+	bool strap;
+};
+
+#endif /* _PDATA_GPIO_TS5500_H */