Allocate device read buffer at bootstrap and do not put it on the stack
since it is pretty big (~200B) and its size will increase adding support
to device hw timestamp.
Moreover this patch fixes following sparse warnings:
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c:250:17: warning: Variable length
array is used.
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c:283:55: error: cannot size
expression

Fixes: 290a6ce1 ("iio: imu: add support to lsm6dsx driver")
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Kernel-doc for @use_count does not currently have a field identifier.
All the rest of the fields do. @use_count is used internally and should
not be accessed directly by the driver so it should be marked as so.

Add [INTERN] identifier to @use_count field.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When building kernel documentation sphinx emits the following warning

	warning: No description found for parameter 'owner'

Add description for struct member 'owner'.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch fixes the following checkpatch.pl issue at multiple lines:

CHECK: Prefer using the BIT macro
Signed-off-by: NSumit Pundir <pundirsumit11@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

By default, watermark is set to '1'. Watermark is used to fine tune
cyclic dma buffer period. In case watermark is left untouched (e.g. 1)
and several channels are being scanned, buffer period is wrongly set
(e.g. to 1 sample). As a consequence, data is never pushed to upper layer.
Fix buffer period size, by taking scan channels number into account.

Fixes: 2763ea05 ("iio: adc: stm32: add optional dma support")
Signed-off-by: NFabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is the patch to the file ti_am335x_adc.c
which fixes the following coccinelle warning:

WARNING: Comparison to bool
Signed-off-by: NVenkat Prashanth B U <venkat.prashanth2498@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a clean-up patch which replaces DEVICE_ATTR() macro with the
file permission specific DEVICE_ATTR_RW() macro for compaction and
readability. Done using coccinelle.
Signed-off-by: NAishwarya Pant <aishpant@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver creates a number of const structures that it stores in the
data field of an of_device_id array.

Add const to the declaration of the location that receives a value
from the data field to ensure that the compiler will continue to check
that the value is not modified and remove the const-dropping cast on
the access to the data field.

Done using Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce regmap API support to access to i2c/spi bus instead of
using a custom support. Set max bulk read to
(32 / SAMPLE_SIZE) * SAMPLE_SIZE since spi_write_then_read() used in
regmap_spi indicates that is the max buffer length to use in order to
avoid a kmalloc for each bus access.
Remove lock mutex since concurrency is already managed by regmap API
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add conf_lock mutex to prevent concurrent FIFO configuration update

Fixes: 290a6ce1 (iio: imu: add support to lsm6dsx driver)
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Apply le16_to_cpu() to data read from the sensor in order to take into
account architecture endianness

Fixes: 290a6ce1 (iio: imu: add support to lsm6dsx driver)
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Move duplicated i2c/spi probe code in hts221_probe()
Signed-off-by: NLorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch affects BME280 and BMP280. The readout of the calibration
data is moved to the probe function. Each sensor data access triggered
reading the full calibration data before this patch. According to the
datasheet, Section 4.4.2., the calibration data is stored in non-volatile
memory.

Since the calibration data does not change, and cannot be changed by the
user, we can reduce bus traffic by reading the calibration data once.
Additionally, proper organization of the data types enables removing
some odd casts in the compensation formulas.
Signed-off-by: NStefan Tatschner <stefan.tatschner@gmail.com>
Tested-by: NAndreas Klinger <ak@it-klinger.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently, the registers are read out once per conversion interval. If
the reading is delayed as the conversion has not yet finished, this extra
time is treated as being part of the readout, although it should delay
the start of the poll interval. This results in the interval starting
slightly earlier in each iteration, until all time between reads is
spent polling the status registers instead of sleeping.

To fix this, the delay has to account for the state of the conversion
ready flag. Whenever the conversion is already finished, schedule the next
read on the regular interval, otherwise schedule it one interval after the
flag bit has been set.

Split the work function in two functions, one for the status poll and one
for reading the values, to be able to note down the time when the flag
bit is raised.
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As the timestamp is no longer (ab-)used to measure the function run time,
it can be taken at the correct time, i.e. when the conversion has finished.
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The iio timestamp clock is user selectable and may be non-monotonic. Also,
only part of the acquisition time is measured, thus the delay was longer
than intended.

Use a monotonic timestamp to track the time for the next poll iteration.
The timestamp is advanced by the sampling interval each iteration. In case
the conversion overrruns the register readout (i.e. fast sampling combined
with a slow bus), one or multiple samples will be dropped.
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When building kernel documentation sphinx emits the following warnings

No description found for parameter 'iio_dev'
Excess function parameter 'indio_dev' description in 'iio_device_register'

These warnings are caused by a macro with a different argument identifier to the
one listed in the kernel-docs.

Change macro argument to be the same as the docs.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Calibration register is used for calculating current register in
hardware according to datasheet:
current = shunt_volt * calib_register / 2048 (ina 226)
current = shunt_volt * calib_register / 4096 (ina 219)

Fix calib_register value to 2048 for ina226 and 4096 for ina 219 in
order to avoid truncation error and provide best precision allowed
by shunt_voltage measurement. Make current scale value follow changes
of shunt_resistor from sysfs as calib_register value is now fixed.

Power_lsb value should also follow shunt_resistor changes as stated in
datasheet:
power_lsb = 25 * current_lsb (ina 226)
power_lsb = 20 * current_lsb (ina 219)

This is a part of the patchset: https://lkml.org/lkml/2017/11/22/394Signed-off-by: NMaciej Purski <m.purski@samsung.com>
Reviewed-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Clean up checkpatch warning:
CHECK: Unnecessary parentheses around 'st->devid != ID_AD7195'
Signed-off-by: NJi-Hun Kim <jihuun.k@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is a patch to the at91_adc.c file that fixes up a brace
warning found by the checkpatch.pl tool
Signed-off-by: NVenkat Prashanth B U <venkat.prashanth2498@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Return value in hx711_reset() should indicate status of dout otherwise the
calling function is reporting an error as false positive

If there are two reads too close to each other, then the second one will
never succeed. This happens especially when using buffered mode with both
channels enabled.

When changing the channel on every trigger event the former 100 ms are not
enough for waiting until the device indicates normal mode.

Wait up to 1 second until the device turns into normal mode.
Signed-off-by: NAndreas Klinger <ak@it-klinger.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add buffer to device data struct and add trigger function

Data format is quite simple:
      voltage - channel 0   32 Bit
      voltage - channel 1   32 Bit
      timestamp             64 Bit

Using both channels at the same time is working quite slow because of
changing the channel which needs a dummy read.
Signed-off-by: NAndreas Klinger <ak@it-klinger.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The conversion time can be up to 16 seconds (8 ms per channel, 2 channels,
1024 times averaging).
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Although the datasheet states the CNVR flag is cleared by reading the
BUS_VOLTAGE register, it is actually cleared by reading any of the
voltage/current/power registers.

The behaviour has been confirmed by TI support:
http://e2e.ti.com/support/amplifiers/current-shunt-monitors/f/931/p/647053/2378282Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The timestamp is inserted into the buffer after the sample data by
iio_push_to_buffers_with_timestamp, document the space requirement for
the timestamp.
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

iio_push_to_buffers_with_timestamp expects a void pointer, so the cast
is both unnecessary and misleading.
Signed-off-by: NStefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On some Meson8 devices the channel muxes are not programmed. This
results in garbage values when trying to read channels that are not set
up.
Fix this by initializing the channel 0 and 1 muxes in
MESON_SAR_ADC_CHAN_10_SW as well as the muxes for all other channels in
MESON_SAR_ADC_AUX_SW based on what the vendor driver does (which is
simply a 1:1 mapping of channel number and channel mux).
This only showed up on Meson8 devices, because for GXBB and newer BL30
is taking care of initializing the channel muxes.

This additionally fixes a typo in the
MESON_SAR_ADC_AUX_SW_MUX_SEL_CHAN_MASK macro because the old definition
assumed that the register fields were 2 bit wide, while they are
actually 3 bit wide.
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

GX SoCs use a 1.2 MHz ADC clock, while the older SoCs use a 1.14 MHz
clock.

A comment in the driver from Amlogic's GPL kernel says that it's
running at 1.28 MHz. However, it's actually programming a divider of
20 + 1. With a XTAL clock of 24 MHz this results in a frequency of
1.14 MHz. (their calculation might be based on a 27 MHz XTAL clock,
but this is not what we have on the Meson8 and Meson8b SoCs).

The ADC was still working with the 1.2MHz clock. In my own tests I did
not see a difference between 1.2 and 1.14 MHz (regardless of the clock
frequency used, the ADC results were identical).
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The name of the file is "current_timetamp_clock" not
"timestamp_clock".

Fixes: bc2b7dab ("iio:core: timestamping clock selection support")
Cc: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

These duplicate includes have been found with scripts/checkincludes.pl but
they have been removed manually to avoid removing false positives.
Signed-off-by: NPravin Shedge <pravin.shedge4linux@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Found with scripts/coccinelle/misc/boolconv.cocci.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add SPDX identifier in stm32's files in IIO directory
Signed-off-by: NBenjamin Gaignard <benjamin.gaignard@st.com>
Acked-by: NFabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Structures st_uvis25_i2c_regmap_config and st_uvis25_spi_regmap_config are
local to the source and do not need to be in global scope, so make them
both static.

Cleans up sparse warnings:
warning: symbol 'st_uvis25_i2c_regmap_config' was not declared. Should
it be static?
warning: symbol 'st_uvis25_spi_regmap_config' was not declared. Should
it be static?
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a sysfs attribute that exposes buffer data available to userspace.
This attribute can be checked at runtime to determine the overall buffer
fill level (across all allocated buffers).
Signed-off-by: NMatt Fornero <matt.fornero@mathworks.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This replaces the custom license information text with the appropriate
SPDX identifier. While the information here stays the same, it is easier
to read.
Signed-off-by: NMartin Kepplinger <martink@posteo.de>
Acked-by: NPeter Meerwald-Stadler <pmeerw@pmeerw.net>
Acked-by: NHarinath Nampally <harinath922@gmail.com>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

getnstimeofday() suffers from the overflow in y2038 on 32-bit
architectures and requires a conversion into the nanosecond format that
we want here.

This changes ssp_parse_dataframe() to use ktime_get_real_ns() directly,
which does not have that problem.

An open question is what time base should be used here. Normally
timestamps should use ktime_get_ns() or ktime_get_boot_ns() to read
monotonic time instead of "real" time, which suffers from time jumps
due to settimeofday() calls or leap seconds.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As discussed with Marc Zyngier: irq_sim_init() and its devres variant
should return the base of the allocated interrupt range on success
rather than 0. This will be modified later - first, change the way
users handle the return value of these routines.
Signed-off-by: NBartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We need the staging fixes in here as well.
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull x86 fixes from Thomas Gleixner:
 "A couple of fixlets for x86:

   - Fix the ESPFIX double fault handling for 5-level pagetables

   - Fix the commandline parsing for 'apic=' on 32bit systems and update
     documentation

   - Make zombie stack traces reliable

   - Fix kexec with stack canary

   - Fix the delivery mode for APICs which was missed when the x86
     vector management was converted to single target delivery. Caused a
     regression due to the broken hardware which ignores affinity
     settings in lowest prio delivery mode.

   - Unbreak modules when AMD memory encryption is enabled

   - Remove an unused parameter of prepare_switch_to"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Switch all APICs to Fixed delivery mode
  x86/apic: Update the 'apic=' description of setting APIC driver
  x86/apic: Avoid wrong warning when parsing 'apic=' in X86-32 case
  x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR)
  x86: Remove unused parameter of prepare_switch_to
  x86/stacktrace: Make zombie stack traces reliable
  x86/mm: Unbreak modules that use the DMA API
  x86/build: Make isoimage work on Debian
  x86/espfix/64: Fix espfix double-fault handling on 5-level systems