ar1021_i2c also supports the ar1020 device I'm using. This is tested.
They also share the same datasheet:

   http://ww1.microchip.com/downloads/en/DeviceDoc/40001393C.pdf

So let users see that they have a compatible in front of them by adding
AR1020 to the driver's description.
Signed-off-by: NMartin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

We should not be forcing edge triggered interrupt, but rather let platform
decide the kind of trigger it needs to use. Also, the driver is not quite
safe with regard to edge-triggered interrupts as it does not try to kick
the controller after requesting/enabling IRQ.
Reviewed-By: NChristian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: NMartin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The name field in structure i2c_device_id is 20 characters, and we expect
it to be NULL-terminated, however we are trying to stuff it with 21 bytes
and thus NULL-terminator is lost. This causes issues when one creates
device with name "MICROCHIP_AR1021_I2C" as i2c core cuts off the last "C",
and automatic module loading by alias does not work as result.

The -I2C suffix in the device name is superfluous, we know what bus we are
dealing with, so let's drop it. Also, no other driver uses capitals, and
the manufacturer name is normally not included, except in very rare cases
of incompatible name collisions.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116211
Fixes: dd4cae8b ("Input: Add Microchip AR1021 i2c touchscreen")
Reviewed-By: NChristian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: NMartin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Use the common kernel coding style and corrently align parameters with
open parenthesis.
Signed-off-by: NMartin Kepplinger <martin.kepplinger@ginzinger.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

clk_prepare_enable() may fail, so we better check its return value and
propagate it in the case of error.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

If imx6ul_tsc_init() fails we should not return directly.

We should disable the previously acquired clocks in this case.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

sparse says:

  sur40.c:372:40: warning: restricted __le32 degrades to integer

the header's data is __le32 so we need to convert it before comparing.
Signed-off-by: NMartin Kepplinger <martink@posteo.de>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

gpiod API allows standard way of specifying GPIO polarity and takes it into
account when reading or setting GPIO state. It also allows us to switch to
common way of obtaining GPIO descriptor and away form legacy platform data.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of keying interrupt trigger off GPIO polarity, let's rely on
platform code to set it up properly for us.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of having standard interrupt handler and manually firing work item
to perform I2C reads, let's switch to threaded interrupts, which were
designed specifically for this purpose.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

We are reading GPIO state in a non-atomic context (workqueue), so we can
use "cansleep" variant, and thus make the driver available on systems where
GPIO controllers require sleeping when reading GPIO state.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of expecting that GPIO is always interrupt source, let's use
interrupt specified in I2C client.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Using devm_* APIs simpifies error handling and device teardown.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Use input_set_capability() instead of manipulating evbit/keybit
masks directly.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of manually converting big endian data on wire into host
endianness, let's use helpers to do that for us. It might save us
a few cycles if host endianness matches what's on wire.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Use idiomatic BIT(n) to form single-bit masks.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Also rename 'priv' variables to eeti.
Reviewed-by: NDaniel Mack <daniel@zonque.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Added missing of_match_table for max11801_ts driver with compatible as
"maxim,max11801_ts"
Signed-off-by: NJagan Teki <jagan@amarulasolutions.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Try a quick read from the device in mip4_query_device() to make sure
that the device is there, as we do not consider failures to retrieve
product name or resolution fatal.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Each time the HWMON devices are read (e.g. battery voltage) while the
touchscreen is held pressed, extra pen-up and pen-down events are
generated. This is fixed by avoiding the UP event when the touchscreen is
stopped.
Signed-off-by: NDavid Jander <david@protonic.nl>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.

But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.

As pointed by Hans de Goede, there's no mssl1680 and this is just used in
some ACPI systems to identify the gsl1680 chip. So isn't included in the
OF device ID table since a DT should use the proper device name instead.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory that lie beyond the end of the endpoint
array should a malicious device lack the expected endpoints.

Fixes: bdb5c57f ("Input: add sur40 driver for Samsung SUR40... ")
Signed-off-by: NJohan Hovold <johan@kernel.org>
Cc: stable@vger.kernel.org	# 3.13
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Update the code to use devm_* API so that driver core will manage
resources.
Signed-off-by: NYegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of manipulating capabilities bits of input device directly, let's
use input_set_capability() API.

Also, stop setting ABS_X/Y bits explicitly as input_set_abs_params() does
this for us.
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

We have switched the driver to use generic device properties API, so there
is no need to check for presence of DT node before trying parse properties.
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

With the switch to devm, there is no need for ad7879_probe() to return the
touchscreen structure, we can use plain error code. This also fixes issue
introduced with devm concersion, where we returned 0 on success (which
worked OK since IS_ERR(0) would not trigger, but was not correct
regardless).

Fixes: 381f688eee3d ("Input: ad7879 - use more devm interfaces")
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The conversion to devm accidentally removed setting up of I2C client data
upon successful probe of the touchscreen. Let's move this setting into the
core, so we do not forger about it again.

Fixes: 381f688eee3d ("Input: ad7879 - use more devm interfaces")
Acked-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add header file to fix these build errors:

../drivers/input/touchscreen/ad7879.c: In function 'ad7879_parse_dt':
../drivers/input/touchscreen/ad7879.c:505:2: error: implicit declaration of function 'device_property_read_u32' [-Werror=implicit-function-declaration]
  err = device_property_read_u32(dev, "adi,resistance-plate-x", &tmp);
  ^
../drivers/input/touchscreen/ad7879.c:512:2: error: implicit declaration of function 'device_property_read_u8' [-Werror=implicit-function-declaration]
  device_property_read_u8(dev, "adi,first-conversion-delay",
  ^
../drivers/input/touchscreen/ad7879.c:521:2: error: implicit declaration of function 'device_property_read_bool' [-Werror=implicit-function-declaration]
  ts->swap_xy = device_property_read_bool(dev, "touchscreen-swapped-x-y");
  ^
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Using regmap this is no longer required.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Up until now only platforms using legacy platform data were able to switch
AUX/VBAT/GPIO pin in GPIO mode and use it as regular GPIO line. Let's
allow platforms using generic device properties to do the same.
Reviewed-by: NMichael Hennerich <michael.hennerich@analog.com>
Tested-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

gpiochip_add now has a managed version, and we can remove sysfs attribute
group via devm_add_action_or_reset (at least until we have devm version of
sysfs_create_group). This allows us to get rid of ad7879_remove().
Reviewed-by: NMichael Hennerich <michael.hennerich@analog.com>
Tested-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of rolling our own infrastructure to provide uniform access to I2C
and SPI buses, let's switch to using regmap.
Reviewed-by: NMichael Hennerich <michael.hennerich@analog.com>
Tested-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Previously, tsc2007 would report as ABS_PRESSURE:
0              for no pressure (resistance infinite)
high value     for soft pressure (high resistance)
low value      for firm pressure (lower resistance)

This does not matter for most applications (e.g. GUI, Menu, Scrolling etc.)
where the ABS_PRESSURE is ignored and only BTN_TOUCH is processed to detect
screen taps.

Only some special graphics applications read the pressure channel and they
will be mixed up by this non-monotonic relation.

So we fix it to become:
0              for no pressure (resistance infinite)
low value      for soft pressure (high resistance)
high value     for firm pressure (lower resistance)

While this patch changes the values reported to userspace, ABS_PRESSURE is
used rarely by userspace. Most software only relies on BTN_TOUCH (boolean),
which is not affected by this patch. Some graphics software makes use of
the interface and does not work correctly with the currently used inverted
behaviour.
Signed-off-by: NH. Nikolaus Schaller <hns@goldelico.com>
Reviewed-By: NSebastian Reichel <sre@kernel.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Rename tsc2007_calculate_pressure to tsc2007_calculate_resistance because
that is what it does.
Signed-off-by: NH. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Do not manipulate evbits/keybits directly, use helper for that.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.

Before this patch:

$ modinfo drivers/input/touchscreen/zet6223.ko | grep alias
alias:          i2c:zet6223

After this patch:

$ modinfo drivers/input/touchscreen/zet6223.ko | grep alias
alias:          of:N*T*Czeitec,zet6223C*
alias:          of:N*T*Czeitec,zet6223
alias:          i2c:zet6223
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

The tsc2007 chip not only has a resistive touch screen controller but
also an external AUX adc imput which can be used for an ambient
light sensor, battery voltage monitoring or any general purpose.

Additionally it can measure the chip temperature.

This extension provides an iio interface for these adc channels.

Since it is not wasting much resources and is very straightforward,
we simply provide all other adc channels as optional iio interfaces
as weel. This can be used for debugging or special applications.

This patch also splits the tsc2007 driver in several source files:
tsc2007.h -- constants, structs and stubs
tsc2007_core.c -- functional parts of the original driver
tsc2007_iio.c -- the optional iio stuff

Makefile magic allows to conditionally link the iio stuff
if CONFIG_IIO=y or =m in a way that it works with
CONFIG_TOUCHSCREEN_TSC2007=m.
Signed-off-by: NH. Nikolaus Schaller <hns@goldelico.com>
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

1. check if chip is really present and don't succeed if it isn't.
2. if it succeeds, power down the chip until accessed
Signed-off-by: NH. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>