iio: adc: mcp320x: Use devm_* APIs

devm_* APIs are device managed and make code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Oskar Andero <oskar.andero@gmail.com>
Signed-off-b

iio: adc: mcp320x: Use devm_* APIs

devm_* APIs are device managed and make code simpler.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Oskar Andero <oskar.andero@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

show more ...

iio: adc: add driver for MCP3204/08 12-bit ADC

This adds support for Microchip's 12 bit AD converters MCP3204 and
MCP3208. These chips communicates over SPI and supports single-ended
and pseudo-diff

iio: adc: add driver for MCP3204/08 12-bit ADC

This adds support for Microchip's 12 bit AD converters MCP3204 and
MCP3208. These chips communicates over SPI and supports single-ended
and pseudo-differential configurations.

Signed-off-by: Oskar Andero <oskar.andero@gmail.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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Replace HTTP links with HTTPS ones: drivers/iio

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

De

Replace HTTP links with HTTPS ones: drivers/iio

Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio:adc:mcp320x: Drop CONFIG_OF and of_match_ptr protections

These just prevent the driver being used with ACPI PRP0001.
They also get cut and paste into new drivers and we want to disco

iio:adc:mcp320x: Drop CONFIG_OF and of_match_ptr protections

These just prevent the driver being used with ACPI PRP0001.
They also get cut and paste into new drivers and we want to discourage
this from happening by cleaning it out in general.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Oskar Andero <oskar.andero@gmail.com>
Cc: Søren Andersen <san@rosetechnology.dk>
Cc: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

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iio: Remove superfluous of_node assignments

If a driver does not assign an of_node to a IIO device to IIO core will
automatically assign the of_node of the parent device. This automatic

iio: Remove superfluous of_node assignments

If a driver does not assign an of_node to a IIO device to IIO core will
automatically assign the of_node of the parent device. This automatic
assignment is done in the iio_device_register() function.

There is a fair amount of drivers that currently manually assign the
of_node of the IIO device. All but 4 of them can make use of the automatic
assignment though.

The exceptions are:
* mxs-lradc-adc: Which uses the of_node of the parent of the parent.
* stm32-dfsdm-adc, stm32-adc and stm32-dac: Which reference the of_node
assigned to the IIO device before iio_device_register() is called.

All other drivers are updated to use automatic assignment. This reduces
the amount of boilerplate code involved in setting up the IIO device.

The patch has mostly been auto-generated with the following semantic patch

// <smpl>
@exists@
expression indio_dev;
expression parent;
@@
indio_dev = \(devm_iio_device_alloc\|iio_device_alloc\)(&parent, ...)
...
-indio_dev->dev.of_node = parent.of_node;

@exists@
expression indio_dev;
expression parent;
@@
indio_dev = \(devm_iio_device_alloc\|iio_device_alloc\)(parent, ...)
...
-indio_dev->dev.of_node = parent->of_node;
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio: remove explicit IIO device parent assignment

This patch applies the semantic patch:
@@
expression I, P, SP;
@@
I = devm_iio_device_alloc(P, SP);
...
- I->

iio: remove explicit IIO device parent assignment

This patch applies the semantic patch:
@@
expression I, P, SP;
@@
I = devm_iio_device_alloc(P, SP);
...
- I->dev.parent = P;

It updates 302 files and does 307 deletions.
This semantic patch also removes some comments like
'/* Establish that the iio_dev is a child of the i2c device */'

But this is is only done in case where the block is left empty.

The patch does not seem to cover all cases. It looks like in some cases a
different variable is used in some cases to assign the parent, but it
points to the same reference.
In other cases, the block covered by ... may be just too big to be covered
by the semantic patch.

However, this looks pretty good as well, as it does cover a big bulk of the
drivers that should remove the parent assignment.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio: adc: mcp320x: Use new structure for SPI transfer delays

In a recent change to the SPI subsystem [1], a new `delay` struct was added
to replace the `delay_usecs`. This change replace

iio: adc: mcp320x: Use new structure for SPI transfer delays

In a recent change to the SPI subsystem [1], a new `delay` struct was added
to replace the `delay_usecs`. This change replaces the current
`delay_usecs` with `delay` for this driver.

The `spi_transfer_delay_exec()` function [in the SPI framework] makes sure
that both `delay_usecs` & `delay` are used (in this order to preserve
backwards compatibility).

[1] commit bebcfd272df6 ("spi: introduce `delay` field for
`spi_transfer` + spi_transfer_delay_exec()")

Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio: adc: mcp320x: Tidy up endian types in type cast.

Fixes the sparse warning:
drivers/iio/adc/mcp320x.c:167:41: warning: incorrect type in argument 1 (different base types)
drivers

iio: adc: mcp320x: Tidy up endian types in type cast.

Fixes the sparse warning:
drivers/iio/adc/mcp320x.c:167:41: warning: incorrect type in argument 1 (different base types)
drivers/iio/adc/mcp320x.c:167:41: expected restricted __be32 const [usertype] *p
drivers/iio/adc/mcp320x.c:167:41: got unsigned int [usertype] *<noident>

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it u

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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iio: adc: mcp320x: Add support for mcp3550/1/3

These ADCs are marketed as single-channel 22 bit delta-sigma ADCs, but
in reality their resolution is 21 bit with an overrange or underrang

iio: adc: mcp320x: Add support for mcp3550/1/3

These ADCs are marketed as single-channel 22 bit delta-sigma ADCs, but
in reality their resolution is 21 bit with an overrange or underrange
of 12% beyond Vref. In other words, "full scale" means +/- 2^20.

This driver does not explicitly signal back to the user when an
overrange or underrange occurs, but the user can detect it by comparing
the raw value to +/- 2^20 (or the scaled value to Vref).

The chips feature an extended temperature range and high accuracy,
low noise characteristics, but their conversion times are slow with
up to 80 ms +/- 2% (on the MCP3550-50).

Hence, unlike the other ADCs supported by the driver, conversion does
not take place in realtime upon lowering CS. Instead, CS is asserted
for 8 usec to start the conversion. After waiting for the duration of
the conversion, the result can be fetched. While waiting, control of
the bus is ceased so it may be used by a different device.

After the result has been fetched and 10 us have passed, the chip goes
into shutdown and an additional power-up delay of 144 clock periods is
then required to wake the analog circuitry upon the next conversion
(footnote below table 4-1, page 16 in the spec).

Optionally, the chips can be used in so-called "continuous conversion
mode": Conversions then take place continuously and the last result may
be fetched at any time without observing a delay. The mode is enabled
by permanently driving CS low, e.g. by wiring it to ground. The driver
only supports "single conversion mode" for now but should be adaptable
to "continuous conversion mode" with moderate effort.

The chips clock out a 3 byte word, unlike the other ADCs supported by
the driver which all have a lower resolution than 16 bit and thus make
do with 2 bytes. Calculate the word length on probe by rounding up the
resolution to full bytes. Crucially, if the clock idles low, the
transfer is preceded by a useless Data Ready bit which increases its
length from 24 bit to 25 bit = 4 bytes (section 5.5 in the spec).
Autosense this based on the SPI slave's configuration.

Cc: Mathias Duckeck <m.duckeck@kunbus.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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Merge 4.14-rc4 into staging-next

We want the staging/iio fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iio: adc: mcp320x: Fix readout of negative voltages

Commit f686a36b4b79 ("iio: adc: mcp320x: Add support for mcp3301")
returns a signed voltage from mcp320x_adc_conversion() but neglects

iio: adc: mcp320x: Fix readout of negative voltages

Commit f686a36b4b79 ("iio: adc: mcp320x: Add support for mcp3301")
returns a signed voltage from mcp320x_adc_conversion() but neglects that
the caller interprets a negative return value as failure. Only mcp3301
(and the upcoming mcp3550/1/3) is affected as the other chips are
incapable of measuring negative voltages.

Fix and while at it, add mcp3301 to the list of supported chips at the
top of the file.

Fixes: f686a36b4b79 ("iio: adc: mcp320x: Add support for mcp3301")
Cc: Andrea Galbusera <gizero@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio: adc: mcp320x: Fix oops on module unload

The driver calls spi_get_drvdata() in its ->remove hook even though it
has never called spi_set_drvdata(). Stack trace for posterity:

iio: adc: mcp320x: Fix oops on module unload

The driver calls spi_get_drvdata() in its ->remove hook even though it
has never called spi_set_drvdata(). Stack trace for posterity:

Unable to handle kernel NULL pointer dereference at virtual address 00000220
Internal error: Oops: 5 [#1] SMP ARM
[<8072f564>] (mutex_lock) from [<7f1400d0>] (iio_device_unregister+0x24/0x7c [industrialio])
[<7f1400d0>] (iio_device_unregister [industrialio]) from [<7f15e020>] (mcp320x_remove+0x20/0x30 [mcp320x])
[<7f15e020>] (mcp320x_remove [mcp320x]) from [<8055a8cc>] (spi_drv_remove+0x2c/0x44)
[<8055a8cc>] (spi_drv_remove) from [<805087bc>] (__device_release_driver+0x98/0x134)
[<805087bc>] (__device_release_driver) from [<80509180>] (driver_detach+0xdc/0xe0)
[<80509180>] (driver_detach) from [<8050823c>] (bus_remove_driver+0x5c/0xb0)
[<8050823c>] (bus_remove_driver) from [<80509ab0>] (driver_unregister+0x38/0x58)
[<80509ab0>] (driver_unregister) from [<7f15e69c>] (mcp320x_driver_exit+0x14/0x1c [mcp320x])
[<7f15e69c>] (mcp320x_driver_exit [mcp320x]) from [<801a78d0>] (SyS_delete_module+0x184/0x1d0)
[<801a78d0>] (SyS_delete_module) from [<80108100>] (ret_fast_syscall+0x0/0x1c)

Fixes: f5ce4a7a9291 ("iio: adc: add driver for MCP3204/08 12-bit ADC")
Cc: Oskar Andero <oskar.andero@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

show more ...

iio: adc: mcp320x: Document struct mcp320x

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: mcp320x: Drop unnecessary of_device_id attributes

The driver sets a .data pointer for each .compatible string but never
calls of_device_get_match_data(). Instead, ADC properti

iio: adc: mcp320x: Drop unnecessary of_device_id attributes

The driver sets a .data pointer for each .compatible string but never
calls of_device_get_match_data(). Instead, ADC properties are looked up
with spi_get_device_id(). The .data pointer is therefore unnecessary,
so drop it.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio: adc: mcp320x: Speed up readout of single-channel ADCs

Single-channel converters such as mcp3001, mcp3201, mcp3301 and the
upcoming mcp3550/1/3 lack a MOSI pin, so there's no need to

iio: adc: mcp320x: Speed up readout of single-channel ADCs

Single-channel converters such as mcp3001, mcp3201, mcp3301 and the
upcoming mcp3550/1/3 lack a MOSI pin, so there's no need to call
mcp320x_channel_to_tx_data() for them.

Moreover, instead of calling spi_read() for these converters, which
generates an spi_message and spi_transfer on the stack on every readout,
it's more efficient to use the spi_message and spi_transfer[] included
in struct mcp320x (as we do for multi-channel ADCs), but initialize the
spi_message only with the receive transfer.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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iio:adc: drop assign iio_info.driver_module and iio_trigger_ops.owner

The equivalent of both of these are now done via macro magic when
the relevant register calls are made. The actual

iio:adc: drop assign iio_info.driver_module and iio_trigger_ops.owner

The equivalent of both of these are now done via macro magic when
the relevant register calls are made. The actual structure
elements will shortly go away.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>

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iio: adc: add missing of_node references to iio_dev

Adding missing indio_dev->dev.of_node references to allow iio consumers
to access the device channels.

Signed-off-by: Matt Ra

iio: adc: add missing of_node references to iio_dev

Adding missing indio_dev->dev.of_node references to allow iio consumers
to access the device channels.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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iio: adc: mcp320x: support more differential voltage measurement

mcp320x driver supports the pseudo-differential mode by
in_voltage'IN+'-voltage'IN-'_raw where (IN+, IN-) = (0, 1), (2, 3

iio: adc: mcp320x: support more differential voltage measurement

mcp320x driver supports the pseudo-differential mode by
in_voltage'IN+'-voltage'IN-'_raw where (IN+, IN-) = (0, 1), (2, 3), ...

mcp320x chips except MCP3X01 can also select swapped IN+ and IN-
pairs in the pseudo-differential mode.
i.e. in_voltage'IN+'-voltage'IN-'_raw where (IN+, IN-) = (1, 0),
(3, 2), ...

If the voltage level of IN+ is equal to or less than IN-, the
resultant code will be 000h. So it is useful to provide these, too.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Oskar Andero <oskar.andero@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Peter Meerwald <pmeerw@pmeerw.net>
Cc: linux-iio@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

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Merge tag 'iio-for-4.5a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First set of new device support, features and cleanups for IIO

Merge tag 'iio-for-4.5a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

First set of new device support, features and cleanups for IIO in the 4.5 cycle

Usual mixed bag, but the big item perhaps in this series is the DMA buffer
support added by Lars-Peter Clausen. It's been in the works for a long time
and it will be interesting to see what hardware support shows up now that
this is available.

New core features + associate cleanup.
* Add generic DMA buffer infrastructure
* Add a DMAengine framework based buffer
Also associated minor changes.
- Set the device buffer watermark based on the minimum watermark for all
attached buffers rather than just the 'primary' one.
- iio_buffer_init - only set the watermark default if one hasn't already
been provided. This allows simple support for devices with a fixed
watermark.
- read only attribute for watermark on fixed watermark devices.
- add explicit buffer enable/disable callbacks to allow the buffer to
do more than trivial actions when it is being turned on and off.
* IIO_VAL_INT support in write_raw_get_fmt function.

New device support
* Freescale MMA7455/7456L accelerometers
* Memsic MXC6255XC accelerometer
* ST lis2dh12 accelerometer
* TI ADS8688 ADC
* TI Palamas (twl6035/7) gpadc

New driver features
* mma8452
- support either of the available interrupt pins to cope with the case
where board layout has lead to a particular one being connected.

Staging graduation
* Dummy driver
- this driver acts as both an example and a test device for those with
out hardware to develop userspace code against.

Cleanups and minor bits and bobs.
* treewide
- Sort out the ordering of iio_device_register/unregister vs runtime
pm function calls so that it's all nice and consistent and not race
prone.
- Check sscanf return values. None of the cases will actually happen as
the strings are supplied internally, but best to be consistent on this.
* ad7780
- switch over to the gpio descriptor interface and remove the now unused
platform data which gets rid of a header entirely.
* ad7793
- drop a pointless else statement.
* at91_adc
- Swap kmalloc_array in for a kmalloc doing the same job.
* dummy
- get rid of some commented out lines that snuck in during the move of
the driver.
* lm3533-als
- Print an error message on provision of an invalid resistance.
* mcp320x
- Add compatible strings with vendor prefix and deprecate those with
no vendor prefix.
* mxs-lradc
- Use BIT macro in various places rather than shifted ones.
* pa12203001
- Power off the chip if the registration fails.
* pulsedlight-lidar-lite
- add runtime PM support.
* xilinx XADC
- constify an iio_buffer_setup_ops structure.

show more ...

Merge tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
"Quite a lot of activity in SPI this cycle, almost all of it in drive

Merge tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
"Quite a lot of activity in SPI this cycle, almost all of it in drivers
with a few minor improvements and tweaks in the core.

- Updates to pxa2xx to support Intel Broxton and multiple chip selects.
- Support for big endian in the bcm63xx driver.
- Multiple slave support for the mt8173
- New driver for the auxiliary SPI controller in bcm2835 SoCs.
- Support for Layerscale SoCs in the Freescale DSPI driver"

* tag 'spi-v4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (87 commits)
spi: pxa2xx: Rework self-initiated platform data creation for non-ACPI
spi: pxa2xx: Add support for Intel Broxton
spi: pxa2xx: Detect number of enabled Intel LPSS SPI chip select signals
spi: pxa2xx: Add output control for multiple Intel LPSS chip selects
spi: pxa2xx: Use LPSS prefix for defines that are Intel LPSS specific
spi: Add DSPI support for layerscape family
spi: ti-qspi: improve ->remove() callback
spi/spi-xilinx: Fix race condition on last word read
spi: Drop owner assignment from spi_drivers
spi: Add THIS_MODULE to spi_driver in SPI core
spi: Setup the master controller driver before setting the chipselect
spi: dw: replace magic constant by DW_SPI_DR
spi: mediatek: mt8173 spi multiple devices support
spi: mediatek: handle controller_data in mtk_spi_setup
spi: mediatek: remove mtk_spi_config
spi: mediatek: Update document devicetree bindings to support multiple devices
spi: fix kernel-doc warnings about missing return desc in spi.c
spi: fix kernel-doc warnings about missing return desc in spi.h
spi: pxa2xx: Align a few defines
spi: pxa2xx: Save other reg_cs_ctrl bits when configuring chip select
...

show more ...

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

show more ...

iio: adc: mcp320x: Add compatible with vendor prefix to OF table

The driver Device Tree binding now documents compatible strings that have
a vendor prefix, so add these to the OF device

iio: adc: mcp320x: Add compatible with vendor prefix to OF table

The driver Device Tree binding now documents compatible strings that have
a vendor prefix, so add these to the OF device ID table to match and mark
the old ones as deprecated explaining that should not be used anymore.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

show more ...

iio: adc: mcp320x: Set struct spi_driver .of_match_table

The driver has an OF id table but the .of_match_table is not set so
the SPI core can't do an OF style match and the table was unu

iio: adc: mcp320x: Set struct spi_driver .of_match_table

The driver has an OF id table but the .of_match_table is not set so
the SPI core can't do an OF style match and the table was unused.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

show more ...

Merge tag 'iio-for-4.3b-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new device support, features and cleanup for t

Merge tag 'iio-for-4.3b-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second set of new device support, features and cleanup for the 4.3 cycle.
Take 2 also includes a fix set that was too late for the 4.2 cycle.

As we had a lot of tools and docs work in this set, I have broken those
out into their own categories in this description.

Fixes from the pull request '4th set of IIO fixes for the 4.2 cycle'.
* Poll functions for both event chardev and the buffer one were returning
negative error codes (via a positive value).
* A recent change to lsiio adding some error handling that was wrong and
stopped the tool working.
* bmg160 was missing some dependencies in Kconfig
* berlin2-adc had a misshandled register (wrote a value rather than a bitmap)

New device support
* TI opt3001 light sensor
* TXC PA12 ALS and proximity sensor.
* mcp3301 ADC support (in mcp320x driver)
* ST lsm303agr accelerometer and magnetometer drivers (plus some st-sensors
common support to allow different WHOAMI register addresses, devices with
fixed scale and allow interrupt equiped magnetometers).
* ADIS16305, ADIS16367, ADIS16445IMUs (in the adis16400 driver)
* ADIS16266 gyro (in the adis16260 driver)
* ADIS16137 gyro (in the adis16136 driver)

New functionality
* mmc35240 DT bindings.
* Inverse unit conversion macros to aid handing of values written to sysfs
attributes.

Core cleanup
* Forward declaration of struct iio_trigger to avoid a compile warning.

Driver cleanup / fixes
* mxs-lradc
- Clarify which parts are supported.
- Fix spelling erorrs.
- Missing/extra includes
- reorder includes
- add datasheet name listings for all usable channels (to allow them
to be bound by name from consumer drivers)
* acpi-als - add some function prefixes as per general iio style.
* bmc150_magn - replace a magic value with the existing define.
* vf610 - determine possible sample frequencies taking into account the
electrical characteristics (defining a minimum sample time)
* dht11
- whitespace
- additional docs
- avoid mulitple assignments in one line
- Use the new funciton ktime_get_resolution_ns to cleanup a nasty trick
previously used for timing.
* Fix all drivers that consider 0 a valid IRQ for historical reasons.
* Export I2C module alias info where previously missing (to allow autoprobing)
* Export OF module alias info where previously missing.
* mmc35240 - switch some variables into arrays to improve readability.
* mlx90614 - define some magic numbers for readability.
* bmc150_magn
- expand area locked by a mutex to cover all the use of the
data->buffer.
- use descriptive naming for a mask instead of a magic value.
* berin2-adc
- pass up an error code rather that a generic error
- constify the iio_chan_spec
- some other little tidy ups.
* stk8312
- fix a dependency on triggered buffers in kconfig
- add a check for invalid attribute values
- improve error handling by returning error codes where possible and
return immediately where relevant
- rework macro defs to use GENMASK etc
- change some variable types to reduce unnecessary casting
- clean up code style
- drop a local buffer copy for bulk reads and use the one in data->buffer
instead.
* adis16400 - the adis16448 gyroscope scale was wrong.
* adis16480 - some more wrong scales for various parts.
* adis16300 - has an undocumented product id and serial number registers so
use them.
* iio_simple_dummy - fix some wrong code indentation.
* bmc150-accel - use the chip ID to detect the chip present rather than
verifying the expected part was there. This was in response to a wrong
ACPI entry on the WinBook TW100.
* mma8452
- fix _get_hp_filter_index
- drop a double include
- pass up an error code rather than rewriting it
- range check input values to attribute writes
- register defs tidy up using GENMASK and reordering them to be easier to
follow.
- various coding style cleanups
- put the Kconfig entry in the write place (alphabetically).

Tools related
* Tools cleanup - drop an explicity NULL comparison, some unnecessary braces,
use the ARRAY_SIZE macro, send error messages to stderr instead of dropping
them in the middle of normal output.
* Fix tools to allow that scale and offset attributes are optional.
* More tools fixes including allowing true 32bit data (previously an overflow
prevented more than 31bits)
* Drop a stray header guard that ended up in a c file.
* Make calc_digits static as it isn't exported or in the header.
* Set ci_array pointer to NULL after free as a protection against non safe
usage of the tools core code. Also convert a double pointer to a single
one as the extra level of indirection was unnecessary.

Docs
* DocBook introduction by Daniel Baluta. Glad we are beginning to
draw together some more introductory docs to suplement the various
tools / examples.
* Drop bytes_per_datum sysfs attribute docs as it no longer exists.
* A whole load of missing / fixing of kernel-doc for the core of IIO.
* Document the trigger name sysfs attribute in the ABI docs.
* Minor typos in the ABI docs related to power down modes.

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