Introduce open and close methods for the input device to keep the device
powered down when it is not in use. Also rework interaction between
interrupt thread and starting/shutting off/resetting the device: instead
of taking a mutex in the intterrupt thread and elsewhere disable interrupts
before transitioning the device in a new state.

The ESD handling is also separated from the IRQ thread; we poll regularly
at a given interval and simply skip reads if we see that valid interrupt
happened not so long ago. This allows us not cancel and reschedule ESD
work from interrupt context all the time.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

We will most likely rearm it yet again the IRQ thread so doing it here
is pointless.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

We do not need process context to send input events so let's switch to
a regular timer. I am going to get rid of taking ts->mutex in
tsc2005_irq_thread() later.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Sparse in unhappy when people use 0 instead of NULL for pointers so
let's rework the way we initialize spi_transfer structure in
tsc2005_cmd() and tsc2005_write().
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

If implementation to perform self-test/reset has not been provided by the
platform code hide 'selftest' sysfs attribute instead of returning error
when someone tries to use it.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

We need to make sure we have time/work initialized before requesting and
enabling interrupts, otherwise we might start using them way too early.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

We know what bus we are residing on (SPI) so let's make this data
available to the users.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Set up SPI device as parent of the input device so it gets placed into
proper place in sysfs tree.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

We should not leave garbage pointers in driver structure after we unbind
it from the device or if bind fails.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Add proper module description so that it would show in 'modinfo'
output.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The boot process is noisy as it is and input core already announces
all new device so let's get rid of the banner message in the driver.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

TSC2005 is not a platform driver so it should not define "platform:tsc2005"
module alias.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Newer code should not be using legacy suspend/resume methods but
rather supply dev_pm_ops structure as it allows better control
over power management.
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Instead of peeking into underlying device and using dev_get/set_drvdata(),
let's use SPI layer's implementation to access driver-private data
(which may be different from driver-core private data).
Tested-by: NAaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Discussions:

http://www.mail-archive.com/linux-omap@vger.kernel.org/msg26748.html

Introduce a driver for the Texas Instruments TSC2005 touchscreen
controller (http://focus.ti.com/docs/prod/folders/print/tsc2005.html).

The patch is based on a driver by Lauri Leukkunen, with modifications
by David Brownell, Phil Carmody, Imre Deak, Hiroshi DOYU, Ari Kauppi,
Tony Lindgren, Jarkko Nikula, Eero Nurkkala and Roman Tereshonkov.
Signed-off-by: NLauri Leukkunen <lauri.leukkunen@nokia.com>
[aaro.koskinen@nokia.com: patch description, rebasing & cleanup]
Signed-off-by: NAaro Koskinen <aaro.koskinen@nokia.com>
[ext-srikar.1.bhavanarayana@nokia.com: various fixes]
Signed-off-by: NSrikar <ext-srikar.1.bhavanarayana@nokia.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>