Drivers using software buffers often store the timestamp in their data buffer
before calling iio_push_to_buffers() with that data buffer. Storing the
timestamp in the buffer usually involves some ugly pointer arithmetic. This
patch adds a new helper function called iio_push_buffers_with_timestamp() which
is similar to iio_push_to_buffers but takes an additional timestamp parameter.
The function will help to hide to uglyness in one central place instead of
exposing it in every driver. If timestamps are enabled for the IIO device
iio_push_buffers_with_timestamp() will store the timestamp as the last element
in buffer, before passing the buffer on to iio_push_buffers(). The buffer needs
large enough to hold the timestamp in this case. If timestamps are disabled
iio_push_buffers_with_timestamp() will behave just like iio_push_buffers().
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Cc: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Cc: Josh Wu <josh.wu@atmel.com>
Cc: Denis Ciocca <denis.ciocca@gmail.com>
Cc: Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
Cc: Ge Gao <ggao@invensense.com>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Marek Vasut <marex@denx.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

dev_to_iio_dev() is a false friend
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Previously the driver had only one-shot reading functionality.
This patch adds continuous sampling support to the driver.

Continuous sampling starts when buffer is enabled.
HW IRQ wakes worker thread that pushes samples to userspace.
Sampling stops when buffer is disabled by userspace.

Patil Rachna (TI) laid the ground work for ADC HW register access.
Russ Dill (TI) fixed bugs in the driver relevant to FIFOs and IRQs.

I fixed channel scanning so multiple ADC channels can be read
simultaneously and pushed to userspace.
Restructured the driver to fit IIO ABI.
And added INDIO_BUFFER_HARDWARE mode.
Signed-off-by: NZubair Lutfullah <zubair.lutfullah@gmail.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NRuss Dill <Russ.Dill@ti.com>
Acked-by: NLee Jones <lee.jones@linaro.org>
Acked-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

12 bit ADC data is stored in 32 bits of storage.
Change from u32 to u16 to reduce wasted memory.
Signed-off-by: NZubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Enable shared IRQ to allow ADC to share IRQ line from
parent MFD core. Only FIFO0 IRQs are for TSC and handled
on the TSC side.

Step mask would be updated from cached variable only previously.
In rare cases when both TSC and ADC are used, the cached
variable gets mixed up.
The step mask is written with the required mask every time.

Rachna Patil (TI) laid ground work for shared IRQ.
Signed-off-by: NZubair Lutfullah <zubair.lutfullah@gmail.com>
Acked-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

sizeof when applied to a pointer typed expression gives the size of the
pointer.
Found by coccinelle spatch "misc/noderef.cocci"
Signed-off-by: NThomas Meyer <thomas@m3y3r.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Acked-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

adding one return value check
fix one kerneldoc
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The max1361 driver uses the same callbacks as the triggered buffer default
buffer setup ops, so just remove the max1361 specific ops and let it use the
default ops.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Now that iio_push_to_buffers() takes a void pointer for the data parameter we
can remove those casts to u8*.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Now that iio_push_to_buffers() takes a void pointer for the data parameter we
can remove those casts to u8*.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Change the type of the 'data' parameter for iio_push_to_buffers() from 'u8 *' to
'const void *'. Drivers typically use the correct type (e.g. __be16 *) for their
data buffer. When passing the buffer to iio_push_to_buffers() it needs to be
cast to 'u8 *' for the compiler to not complain (and also having to add __force
if we want to keep sparse happy as well). Since the buffer implementation should
not care about the data layout (except the size of one sample) using a void
pointer is the correct thing to do. Also make it const as the buffer
implementations are not supposed to modify it.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The iio_cb_access struct is never modified so we can mark it as const.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

and drop obsolete #define
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Doing this makes it possible to access this control from within the kernel.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Acked-by: NPeter Meerwald <pmeerw@pmeerw.net>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>

Note that as this driver has output as well as output channels an
example of info_mask_shared_by_all that makes any sense does not exist.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>

These two additional info_mask bitmaps should allow all 'standard'
numeric attributes to be handled using the read_raw and write_raw
callbacks.  Whilst this should reduce code, the more important element
is that this makes these values easily accessible to in kernel users
of IIO devices.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>

Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>

Somehow this got missed when dropping all the code that used it
prior to the split.  Remove it now, there are no users.
Signed-off-by: NJonathan Cameron <jic23@kernel.org>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>

Use wake_up_interruptible_poll() instead of wake_up_interruptible() to only wake
up those threads that listen for input poll notifications.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

We can skip having to loop through all the device's buffers to see if a certain
buffer is active, if we let the buffer's list head point to itself when the
buffer is inactive.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

IIO uses anon_inode_get() to allocate file descriptors as part
of its ioctls. But those ioctls are lacking a flag argument
allowing userspace to choose options for the newly opened file
descriptor.

In such case it's advised to use O_CLOEXEC by default so that
userspace is allowed to choose, without race, if the file descriptor
is going to be inherited across exec().

KVM usage of anon_inode_getfd() was fixed in a previous patchset [1],
so IIO is the only subsystem using anon_inode_getfd() with a fixed set
of flags not including O_CLOEXEC.

This patch set O_CLOEXEC flag on the event file descriptor created
with anon_inode_getfd() to not leak file descriptors across exec().

Links:

- Secure File Descriptor Handling (Ulrich Drepper, 2008)
  http://udrepper.livejournal.com/20407.html

- Excuse me son, but your code is leaking !!! (Dan Walsh, March 2012)
  http://danwalsh.livejournal.com/53603.html

- [1] kvm: use anon_inode_getfd() with O_CLOEXEC flag
  http://lkml.kernel.org/r/cover.1377372576.git.ydroneaud@opteya.comSigned-off-by: NYann Droneaud <ydroneaud@opteya.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Add a new driver for the ambient light/proximity sensor
device. The driver exposes three channels: light_clear
light_ir and proximity. It also supports triggered buffer,
high and low ambient light threshold event and proximity
detection events.
Signed-off-by: NJacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

This patch adds device tree binding documentation
for the gp2ap020a00f proximity/als sensor.
Signed-off-by: NJacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

chip has four 16-bit channels for red, green, blue, clear color
intensity; driver supports the TCS3x7x family of devices and was
tested with a TCS34725 chip; further information here:
http://www.ams.com/eng/Products/Light-Sensors/Color-Sensor/TCS34725

v2 (thanks to Jonathan Cameron):
* drop dynamic buffer allocation, buffer is in tcs3472_data
* limit sysfs output to PAGE_SIZE
* check val2 == 0 when writing CALIBSCALE
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Cc: Jon Brenner <jon.brenner@ams.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

At the moment the number of channels specified is dictated by the first
sensor supported by the driver. As we add support for more sensors this
is likely to vary. Instead of using the ARRAY_SIZE() of the LPS331AP's
channel specifier we'll use a new adaptable 'struct st_sensors' element
instead.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Acked-by: NDenis Ciocca <denis.ciocca@st.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Due to the MACRO used, the task of reading, understanding and maintaining
the LPS331AP's channel descriptor is substantially difficult. This patch
is based on the view that it's better to have easy to read, maintainable
code than to save a few lines here and there. For that reason we're
expanding the array so initialisation is completed in full.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

They're currently named *_1_*, for 'Sensor 1', but the code will be much
more readable if we use the naming convention *_LPS331AP_* instead.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Saving a few lines of code.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Some chips either don't support it or fail to provide adequate documentation,
so sometimes it's impossible to enable the feature even if it is supported.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Acked-by: NDenis Ciocca <denis.ciocca@st.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

driver for the TSL4531 family of 16-bit I2C ambient light
sensors; information is here:
http://www.ams.com/eng/Products/Light-Sensors/Ambient-Light-Sensor-ALS/TSL45315

the chip offers simple lux output

v3 (thanks Lars-Peter Clausen):
* add mutex to when updating integration time
* fix chip ID checking
* code cleanups
v2:
* rename to tsl4351
* use INT_TIME
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Integration time is in seconds; it controls the measurement
time and influences the gain of a sensor.

There are two typical ways that scaling is implemented in a device:
1) input amplifier,
2) reference to the ADC is changed.
These both result in the accuracy of the ADC varying (by applying its
sampling over a more relevant range).

Integration time is a way of dealing with noise inherent in the analog
sensor itself.  In the case of a light sensor, a mixture of photon noise
and device specific noise.  Photon noise is dealt with by either improving
the efficiency of the sensor, (more photons actually captured) which is not
easily varied dynamically, or by integrating the measurement over a longer
time period.  Note that this can also be thought of as an averaging of a
number of individual samples and is infact sometimes implemented this way.
Altering integration time implies that the duration of a measurement changes,
a fact the device's user may be interested in.

Hence it makes sense to distinguish between integration time and simple
scale. In some devices both types of control are present and whilst they
will have similar effects on the amplitude of the reading, their effect
on the noise of the measurements will differ considerably.

Used by adjd_s311, tsl4531, tcs3472
The following drivers have similar controls (and could be adapted):
* tsl2563 (integration time is controlled via CALIBSCALE among other things)
* tsl2583 (has integration_time device_attr, but driver doesn't use channels yet)
* tsl2x7x (has integration_time attr)
Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Cc: Jon Brenner <jon.brenner@ams.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Barry Song <21cnbao@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

devm_iio_device_alloc makes code simpler.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Cc: Graff Yang <graff.yang@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>