Some STMPE devices support entering sleep mode automatically on a
specified timeout of inactivity on the I2C bus with the host system.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Sundar R Iyer <sundar.iyer@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Add support for the STMPE family of I/O Expanders from
STMicroelectronics.  These devices include upto 24 gpios and a varying
selection of blocks, including PWM, keypad, and touchscreen controllers.
This patch adds the MFD core.

[l.fu@pengutronix.de: fix stmpe811 enable hook]
[l.fu@pengutronix.de: add touchscreen platform data]
Acked-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>