930 Commits

Author SHA1 Message Date
Jonathan Cameron
91664385e6 iio: adc: ti-ads8688: Fix alignment of buffer in iio_push_to_buffers_with_timestamp()
[ Upstream commit 61fa5dfa5f52806f5ce37a0ba5712c271eb22f98 ]

Add __aligned(8) to ensure the buffer passed to
iio_push_to_buffers_with_timestamp() is suitable for the naturally
aligned timestamp that will be inserted.

Fixes: f214ff521fb1 ("iio: ti-ads8688: Update buffer allocation for timestamps")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210613152301.571002-5-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:15:56 +02:00
Jonathan Cameron
3e8164ccae iio: adc: mxs-lradc: Fix buffer alignment in iio_push_to_buffers_with_timestamp()
[ Upstream commit 6a6be221b8bd561b053f0701ec752a5ed9007f69 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.
Add a comment on why the buffer is the size it is as not immediately
obvious.

Found during an audit of all calls of this function.

Fixes: 6dd112b9f85e ("iio: adc: mxs-lradc: Add support for ADC driver")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andreas Klinger <ak@it-klinger.de>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210613152301.571002-4-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:15:56 +02:00
Jonathan Cameron
3ce7cd150e iio: adc: hx711: Fix buffer alignment in iio_push_to_buffers_with_timestamp()
[ Upstream commit afe2a789fbf7acd1a05407fc7839cc08d23825e3 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of this function.

Fixes: d3bf60450d47 ("iio: hx711: add triggered buffer support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Andreas Klinger <ak@it-klinger.de>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20210613152301.571002-3-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:15:56 +02:00
Jonathan Cameron
df848efb61 iio: adc: vf610: Fix buffer alignment in iio_push_to_buffers_with_timestamp()
[ Upstream commit 7765dfaa22ea08abf0c175e7553826ba2a939632 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of uses of
iio_push_to_buffers_with_timestamp()

Fixes: 0010d6b44406 ("iio: adc: vf610: Add IIO buffer support for Vybrid ADC")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com>
Cc: Sanchayan Maity <maitysanchayan@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210501170121.512209-10-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:15:54 +02:00
Jonathan Cameron
b0d27f41be iio: adc: ti-ads1015: Fix buffer alignment in iio_push_to_buffers_with_timestamp()
[ Upstream commit d85d71dd1ab67eaa7351f69fec512d8f09d164e1 ]

To make code more readable, use a structure to express the channel
layout and ensure the timestamp is 8 byte aligned.

Found during an audit of all calls of this function.

Fixes: ecc24e72f437 ("iio: adc: Add TI ADS1015 ADC driver support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Daniel Baluta <daniel.baluta@nxp.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210501170121.512209-9-jic23@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-07-20 16:15:54 +02:00
YueHaibing
e95ba554ec iio: adc: ad7793: Add missing error code in ad7793_setup()
commit 4ed243b1da169bcbc1ec5507867e56250c5f1ff9 upstream.

Set error code while device ID query failed.

Fixes: 88bc30548aae ("IIO: ADC: New driver for AD7792/AD7793 3 Channel SPI ADC")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-03 08:38:04 +02:00
Jonathan Albrieux
ed1323e4d5 iio:adc:qcom-spmi-vadc: add default scale to LR_MUX2_BAT_ID channel
commit 7d200b283aa049fcda0d43dd6e03e9e783d2799c upstream.

Checking at both msm8909-pm8916.dtsi and msm8916.dtsi from downstream
it is indicated that "batt_id" channel has to be scaled with the default
function:

	chan@31 {
		label = "batt_id";
		reg = <0x31>;
		qcom,decimation = <0>;
		qcom,pre-div-channel-scaling = <0>;
		qcom,calibration-type = "ratiometric";
		qcom,scale-function = <0>;
		qcom,hw-settle-time = <0xb>;
		qcom,fast-avg-setup = <0>;
	};

Change LR_MUX2_BAT_ID scaling accordingly.

Signed-off-by: Jonathan Albrieux <jonathan.albrieux@gmail.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Fixes: 7c271eea7b8a ("iio: adc: spmi-vadc: Changes to support different scaling")
Link: https://lore.kernel.org/r/20210113151808.4628-2-jonathan.albrieux@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 11:07:35 +01:00
Jonathan Cameron
bf348faad0 iio:adc:stm32-adc: Add HAS_IOMEM dependency
commit 121875b28e3bd7519a675bf8ea2c2e793452c2bd upstream.

Seems that there are config combinations in which this driver gets enabled
and hence selects the MFD, but with out HAS_IOMEM getting pulled in
via some other route.  MFD is entirely contained in an
if HAS_IOMEM block, leading to the build issue in this bugzilla.

https://bugzilla.kernel.org/show_bug.cgi?id=209889

Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210124195034.22576-1-jic23@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-24 11:07:35 +01:00
Qinglang Miao
3c472f0a8b iio: adc: rockchip_saradc: fix missing clk_disable_unprepare() on error in rockchip_saradc_resume
commit 560c6b914c6ec7d9d9a69fddbb5bf3bf71433e8b upstream.

Fix the missing clk_disable_unprepare() of info->pclk
before return from rockchip_saradc_resume in the error
handling case when fails to prepare and enable info->clk.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Fixes: 44d6f2ef94f9 ("iio: adc: add driver for Rockchip saradc")
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201103120743.110662-1-miaoqinglang@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:26:15 +01:00
Jonathan Cameron
da58185f7b iio:adc:ti-adc12138 Fix alignment issue with timestamp
commit 293e809b2e8e608b65a949101aaf7c0bd1224247 upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses an array of smaller elements on the stack.

We move to a suitable structure in the iio_priv() data with alignment
explicitly requested.  This data is allocated with kzalloc so no
data can leak apart from previous readings. Note that previously
no leak at all could occur, but previous readings should never
be a problem.

In this case the timestamp location depends on what other channels
are enabled. As such we can't use a structure without misleading
by suggesting only one possible timestamp location.

Fixes: 50a6edb1b6e0 ("iio: adc: add ADC12130/ADC12132/ADC12138 ADC driver")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200722155103.979802-26-jic23@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05 11:08:50 +01:00
Jonathan Cameron
8a8900553d iio:adc:ti-adc0832 Fix alignment issue with timestamp
commit 39e91f3be4cba51c1560bcda3a343ed1f64dc916 upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses an array of smaller elements on the stack.

We fix this issues by moving to a suitable structure in the iio_priv()
data with alignment explicitly requested.  This data is allocated
with kzalloc so no data can leak apart from previous readings.
Note that previously no data could leak 'including' previous readings
but I don't think it is an issue to potentially leak them like
this now does.

In this case the postioning of the timestamp is depends on what
other channels are enabled. As such we cannot use a structure to
make the alignment explicit as it would be missleading by suggesting
only one possible location for the timestamp.

Fixes: 815bbc87462a ("iio: ti-adc0832: add triggered buffer support")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200722155103.979802-25-jic23@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-05 11:08:50 +01:00
Jonathan Cameron
62d46fa157 iio:adc:ti-adc081c Fix alignment and data leak issues
commit 54f82df2ba86e2a8e9cbf4036d192366e3905c89 upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses an array of smaller elements on the stack.
As Lars also noted this anti pattern can involve a leak of data to
userspace and that indeed can happen here.  We close both issues by
moving to a suitable structure in the iio_priv().

This data is allocated with kzalloc so no data can leak apart
from previous readings.

The eplicit alignment of ts is necessary to ensure correct padding
on x86_32 where s64 is only aligned to 4 bytes.

Fixes: 08e05d1fce5c ("ti-adc081c: Initial triggered buffer support")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:27 +02:00
Jonathan Cameron
234974cf05 iio:adc:max1118 Fix alignment of timestamp and data leak issues
commit db8f06d97ec284dc018e2e4890d2e5035fde8630 upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses an array of smaller elements on the stack.
As Lars also noted this anti pattern can involve a leak of data to
userspace and that indeed can happen here.  We close both issues by
moving to a suitable structure in the iio_priv() data.

This data is allocated with kzalloc so no data can leak apart
from previous readings.

The explicit alignment of ts is necessary to ensure correct padding
on architectures where s64 is only 4 bytes aligned such as x86_32.

Fixes: a9e9c7153e96 ("iio: adc: add max1117/max1118/max1119 ADC driver")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:27 +02:00
Jonathan Cameron
e7a63f2877 iio:adc:ina2xx Fix timestamp alignment issue.
commit f8cd222feb82ecd82dcf610fcc15186f55f9c2b5 upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses a 32 byte array of smaller elements on the stack.
As Lars also noted this anti pattern can involve a leak of data to
userspace and that indeed can happen here.  We close both issues by
moving to a suitable structure in the iio_priv() data with alignment
explicitly requested.  This data is allocated with kzalloc so no
data can leak apart from previous readings. The explicit alignment
isn't technically needed here, but it reduced fragility and avoids
cut and paste into drivers where it will be needed.

If we want this in older stables will need manual backport due to
driver reworks.

Fixes: c43a102e67db ("iio: ina2xx: add support for TI INA2xx Power Monitors")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Cc: Marc Titinger <mtitinger@baylibre.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:27 +02:00
Jonathan Cameron
5acf848605 iio:adc:ti-adc084s021 Fix alignment and data leak issues.
commit a661b571e3682705cb402a5cd1e970586a3ec00f upstream.

One of a class of bugs pointed out by Lars in a recent review.
iio_push_to_buffers_with_timestamp assumes the buffer used is aligned
to the size of the timestamp (8 bytes).  This is not guaranteed in
this driver which uses an array of smaller elements on the stack.
As Lars also noted this anti pattern can involve a leak of data to
userspace and that indeed can happen here.  We close both issues by
moving to a suitable structure in the iio_priv().

This data is allocated with kzalloc so no data can leak apart from
previous readings.

The force alignment of ts is not strictly necessary in this case
but reduces the fragility of the code.

Fixes: 3691e5a69449 ("iio: adc: add driver for the ti-adc084s021 chip")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: Mårten Lindahl <martenli@axis.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:27 +02:00
Maxim Kochetkov
da2eb70c3c iio: adc: ti-ads1015: fix conversion when CONFIG_PM is not set
commit e71e6dbe96ac80ac2aebe71a6a942e7bd60e7596 upstream.

To stop conversion ads1015_set_power_state() function call unimplemented
function __pm_runtime_suspend() from pm_runtime_put_autosuspend()
if CONFIG_PM is not set.
In case of CONFIG_PM is not set: __pm_runtime_suspend() returns -ENOSYS,
so ads1015_read_raw() failed because ads1015_set_power_state() returns an
error.

If CONFIG_PM is disabled, there is no need to start/stop conversion.
Fix it by adding return 0 function variant if CONFIG_PM is not set.

Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Fixes: ecc24e72f437 ("iio: adc: Add TI ADS1015 ADC driver support")
Tested-by: Maxim Kiselev <bigunclemax@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:26 +02:00
Angelo Compagnucci
4fea86da6a iio: adc: mcp3422: fix locking on error path
[ Upstream commit a139ffa40f0c24b753838b8ef3dcf6ad10eb7854 ]

Reading from the chip should be unlocked on error path else the lock
could never being released.

Fixes: 07914c84ba30 ("iio: adc: Add driver for Microchip MCP3422/3/4 high resolution ADC")
Fixes: 3f1093d83d71 ("iio: adc: mcp3422: fix locking scope")
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Angelo Compagnucci <angelo.compagnucci@gmail.com>
Link: https://lore.kernel.org/r/20200901093218.1500845-1-angelo.compagnucci@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-09-17 13:45:26 +02:00
Angelo Compagnucci
4e8bf9d2ba iio: adc: mcp3422: fix locking scope
commit 3f1093d83d7164e4705e4232ccf76da54adfda85 upstream.

Locking should be held for the entire reading sequence involving setting
the channel, waiting for the channel switch and reading from the
channel.
If not, reading from a channel can result mixing with the reading from
another channel.

Fixes: 07914c84ba30 ("iio: adc: Add driver for Microchip MCP3422/3/4 high resolution ADC")
Signed-off-by: Angelo Compagnucci <angelo.compagnucci@gmail.com>
Link: https://lore.kernel.org/r/20200819075525.1395248-1-angelo.compagnucci@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 13:45:26 +02:00
Fabrice Gasnier
d268f8ddbb iio: adc: stm32-dfsdm: fix device used to request dma
[ Upstream commit b455d06e6fb3c035711e8aab1ca18082ccb15d87 ]

DMA channel request should use device struct from platform device struct.
Currently it's using iio device struct. But at this stage when probing,
device struct isn't yet registered (e.g. device_register is done in
iio_device_register). Since commit 71723a96b8b1 ("dmaengine: Create
symlinks between DMA channels and slaves"), a warning message is printed
as the links in sysfs can't be created, due to device isn't yet registered:
- Cannot create DMA slave symlink
- Cannot create DMA dma:rx symlink

Fix this by using device struct from platform device to request dma chan.

Fixes: eca949800d2d ("IIO: ADC: add stm32 DFSDM support for PDM microphone")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:37:45 +02:00
Peter Ujfalusi
ae862e350a iio: adc: stm32-dfsdm: Use dma_request_chan() instead dma_request_slave_channel()
[ Upstream commit a9ab624edd9186fbad734cfe5d606a6da3ca34db ]

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Olivier Moysan <olivier.moysan@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:37:45 +02:00
Fabrice Gasnier
90af01f6d9 iio: adc: stm32-adc: fix device used to request dma
[ Upstream commit 52cd91c27f3908b88e8b25aed4a4d20660abcc45 ]

DMA channel request should use device struct from platform device struct.
Currently it's using iio device struct. But at this stage when probing,
device struct isn't yet registered (e.g. device_register is done in
iio_device_register). Since commit 71723a96b8b1 ("dmaengine: Create
symlinks between DMA channels and slaves"), a warning message is printed
as the links in sysfs can't be created, due to device isn't yet registered:
- Cannot create DMA slave symlink
- Cannot create DMA dma:rx symlink

Fix this by using device struct from platform device to request dma chan.

Fixes: 2763ea0585c99 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:37:44 +02:00
Peter Ujfalusi
cdaedaba68 iio: adc: stm32-adc: Use dma_request_chan() instead dma_request_slave_channel()
[ Upstream commit 735404b846dffcb320264f62b76e6f70012214dd ]

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 17:37:44 +02:00
YueHaibing
55e889ead4 iio:ad7797: Use correct attribute_group
commit 28535877ac5b2b84f0d394fd67a5ec71c0c48b10 upstream.

It should use ad7797_attribute_group in ad7797_info,
according to commit ("iio:ad7793: Add support for the ad7796 and ad7797").

Scale is fixed for the ad7796 and not programmable, hence
should not have the scale_available attribute.

Fixes: fd1a8b912841 ("iio:ad7793: Add support for the ad7796 and ad7797")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:25:49 +02:00
Lars-Peter Clausen
5d42466b62 iio: xilinx-xadc: Make sure not exceed maximum samplerate
commit 3b7f9dbb827ce8680b98490215e698b6079a9ec5 upstream.

The XADC supports a samplerate of up to 1MSPS. Unfortunately the hardware
does not have a FIFO, which means it generates an interrupt for each
conversion sequence. At one 1MSPS this creates an interrupt storm that
causes the system to soft-lock.

For this reason the driver limits the maximum samplerate to 150kSPS.
Currently this check is only done when setting a new samplerate. But it is
also possible that the initial samplerate configured in the FPGA bitstream
exceeds the limit.

In this case when starting to capture data without first changing the
samplerate the system can overload.

To prevent this check the currently configured samplerate in the probe
function and reduce it to the maximum if necessary.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:31:26 +02:00
Lars-Peter Clausen
9bb4af3663 iio: xilinx-xadc: Fix sequencer configuration for aux channels in simultaneous mode
commit 8bef455c8b1694547ee59e8b1939205ed9d901a6 upstream.

The XADC has two internal ADCs. Depending on the mode it is operating in
either one or both of them are used. The device manual calls this
continuous (one ADC) and simultaneous (both ADCs) mode.

The meaning of the sequencing register for the aux channels changes
depending on the mode.

In continuous mode each bit corresponds to one of the 16 aux channels. And
the single ADC will convert them one by one in order.

In simultaneous mode the aux channels are split into two groups the first 8
channels are assigned to the first ADC and the other 8 channels to the
second ADC. The upper 8 bits of the sequencing register are unused and the
lower 8 bits control both ADCs. This means a bit needs to be set if either
the corresponding channel from the first group or the second group (or
both) are set.

Currently the driver does not have the special handling required for
simultaneous mode. Add it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:31:25 +02:00
Lars-Peter Clausen
96a0dc7e5e iio: xilinx-xadc: Fix clearing interrupt when enabling trigger
commit f954b098fbac4d183219ce5b42d76d6df2aed50a upstream.

When enabling the trigger and unmasking the end-of-sequence (EOS) interrupt
the EOS interrupt should be cleared from the status register. Otherwise it
is possible that it was still set from a previous capture. If that is the
case the interrupt would fire immediately even though no conversion has
been done yet and stale data is being read from the device.

The old code only clears the interrupt if the interrupt was previously
unmasked. Which does not make much sense since the interrupt is always
masked at this point and in addition masking the interrupt does not clear
the interrupt from the status register. So the clearing needs to be done
unconditionally.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:31:25 +02:00
Lars-Peter Clausen
66961103c0 iio: xilinx-xadc: Fix ADC-B powerdown
commit e44ec7794d88f918805d700240211a9ec05ed89d upstream.

The check for shutting down the second ADC is inverted. This causes it to
be powered down when it should be enabled. As a result channels that are
supposed to be handled by the second ADC return invalid conversion results.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Fixes: bdc8cda1d010 ("iio:adc: Add Xilinx XADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:31:25 +02:00
Olivier Moysan
7363ec6221 iio: adc: stm32-adc: fix sleep in atomic context
commit e2042d2936dfc84e9c600fe9b9d0039ca0e54b7d upstream.

This commit fixes the following error:
"BUG: sleeping function called from invalid context at kernel/irq/chip.c"

In DMA mode suppress the trigger irq handler, and make the buffer
transfers directly in DMA callback, instead.

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 16:31:25 +02:00
Eugen Hristev
78863b863a iio: adc: at91-sama5d2_adc: fix differential channels in triggered mode
commit a500f3bd787f8224341e44b238f318c407b10897 upstream.

The differential channels require writing the channel offset register (COR).
Otherwise they do not work in differential mode.
The configuration of COR is missing in triggered mode.

Fixes: 5e1a1da0f8c9 ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 08:06:10 +01:00
Geert Uytterhoeven
346812c25f iio: adc: max9611: Fix too short conversion time delay
[ Upstream commit 9fd229c478fbf77c41c8528aa757ef14210365f6 ]

As of commit b9ddd5091160793e ("iio: adc: max9611: Fix temperature
reading in probe"), max9611 initialization sometimes fails on the
Salvator-X(S) development board with:

    max9611 4-007f: Invalid value received from ADC 0x8000: aborting
    max9611: probe of 4-007f failed with error -5

The max9611 driver tests communications with the chip by reading the die
temperature during the probe function, which returns an invalid value.

According to the datasheet, the typical ADC conversion time is 2 ms, but
no minimum or maximum values are provided.  Maxim Technical Support
confirmed this was tested with temperature Ta=25 degreeC, and promised
to inform me if a maximum/minimum value is available (they didn't get
back to me, so I assume it is not).

However, the driver assumes a 1 ms conversion time.  Usually the
usleep_range() call returns after more than 1.8 ms, hence it succeeds.
When it returns earlier, the data register may be read too early, and
the previous measurement value will be returned.  After boot, this is
the temperature POR (power-on reset) value, causing the failure above.

Fix this by increasing the delay from 1000-2000 µs to 3000-3300 µs.

Note that this issue has always been present, but it was exposed by the
aformentioned commit.

Fixes: 69780a3bbc0b1e7e ("iio: adc: Add Maxim max9611 ADC driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09 10:18:55 +01:00
Alexandru Ardelean
77a6a2656c iio: dln2-adc: fix iio_triggered_buffer_postenable() position
[ Upstream commit a7bddfe2dfce1d8859422124abe1964e0ecd386e ]

The iio_triggered_buffer_postenable() hook should be called first to
attach the poll function. The iio_triggered_buffer_predisable() hook is
called last (as is it should).

This change moves iio_triggered_buffer_postenable() to be called first. It
adds iio_triggered_buffer_predisable() on the error paths of the postenable
hook.
For the predisable hook, some code-paths have been changed to make sure
that the iio_triggered_buffer_predisable() hook gets called in case there
is an error before it.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-31 16:35:33 +01:00
Miquel Raynal
eec8f08dc8 iio: adc: max1027: Reset the device at probe time
[ Upstream commit db033831b4f5589f9fcbadb837614a7c4eac0308 ]

All the registers are configured by the driver, let's reset the chip
at probe time, avoiding any conflict with a possible earlier
configuration.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-31 16:35:17 +01:00
Stefan Agner
cd3de5870c iio: adc: max9611: explicitly cast gain_selectors
[ Upstream commit b1ec0802503820ccbc894aadfd2a44da20232f5e ]

After finding a reasonable gain, the function converts the configured
gain to a gain configuration option selector enum max9611_csa_gain.
Make the conversion clearly visible by using an explicit cast. This
also avoids a warning seen with clang:
  drivers/iio/adc/max9611.c:292:16: warning: implicit conversion from
      enumeration type 'enum max9611_conf_ids' to different enumeration
      type 'enum max9611_csa_gain' [-Wenum-conversion]
                        *csa_gain = gain_selectors[i];
                                  ~ ^~~~~~~~~~~~~~~~~

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20 18:45:20 +01:00
Fabrice Gasnier
a428996147 iio: adc: stm32-adc: fix stopping dma
commit e6afcf6c598d6f3a0c9c408bfeddb3f5730608b0 upstream.

There maybe a race when using dmaengine_terminate_all(). The predisable
routine may call iio_triggered_buffer_predisable() prior to a pending DMA
callback.
Adopt dmaengine_terminate_sync() to ensure there's no pending DMA request
before calling iio_triggered_buffer_predisable().

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12 19:20:40 +01:00
Remi Pommarel
78e6415d4f iio: adc: meson_saradc: Fix memory allocation order
[ Upstream commit de10ac47597e7a3596b27631d0d5ce5f48d2c099 ]

meson_saradc's irq handler uses priv->regmap so make sure that it is
allocated before the irq get enabled.

This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
managed resources are freed in the inverted order they had been
allocated, priv->regmap was freed before the spurious fake irq that
CONFIG_DEBUG_SHIRQ adds called the handler.

Fixes: 3af109131b7eb8 ("iio: adc: meson-saradc: switch from polling to interrupt mode")
Reported-by: Elie Roudninski <xademax@gmail.com>
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Elie ROUDNINSKI <xademax@gmail.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-06 13:05:39 +01:00
Fabrice Gasnier
f6c715708f iio: adc: stm32-adc: fix a race when using several adcs with dma and irq
[ Upstream commit dcb10920179ab74caf88a6f2afadecfc2743b910 ]

End of conversion may be handled by using IRQ or DMA. There may be a
race when two conversions complete at the same time on several ADCs.
EOC can be read as 'set' for several ADCs, with:
- an ADC configured to use IRQs. EOCIE bit is set. The handler is normally
  called in this case.
- an ADC configured to use DMA. EOCIE bit isn't set. EOC triggers the DMA
  request instead. It's then automatically cleared by DMA read. But the
  handler gets called due to status bit is temporarily set (IRQ triggered
  by the other ADC).
So both EOC status bit in CSR and EOCIE control bit must be checked
before invoking the interrupt handler (e.g. call ISR only for
IRQ-enabled ADCs).

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-17 13:45:23 -07:00
Fabrice Gasnier
a9968a4d63 iio: adc: stm32-adc: move registers definitions
[ Upstream commit 31922f62bb527d749b99dbc776e514bcba29b7fe ]

Move STM32 ADC registers definitions to common header.
This is precursor patch to:
- iio: adc: stm32-adc: fix a race when using several adcs with dma and irq

It keeps registers definitions as a whole block, to ease readability and
allow simple access path to EOC bits (readl) in stm32-adc-core driver.

Fixes: 2763ea0585c9 ("iio: adc: stm32: add optional dma support")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-17 13:45:22 -07:00
Hans de Goede
811616a640 iio: adc: axp288: Override TS pin bias current for some models
commit 972917419a0ba25afbf69d5d8c9fa644d676f887 upstream.

Since commit 9bcf15f75cac ("iio: adc: axp288: Fix TS-pin handling") we
preserve the bias current set by the firmware at boot.  This fixes issues
we were seeing on various models, but it seems our old hardcoded 80ųA bias
current was working around a firmware bug on at least one model laptop.

In order to both have our cake and eat it, this commit adds a dmi based
list of models where we need to override the firmware set bias current and
adds the one model we now know needs this to it: The Lenovo Ideapad 100S
(11 inch version).

Fixes: 9bcf15f75cac ("iio: adc: axp288: Fix TS-pin handling")
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=203829
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-17 13:45:13 -07:00
Marco Felsch
99757b1d9c iio: adc: ad799x: fix probe error handling
commit c62dd44901cfff12acc5792bf3d2dec20bcaf392 upstream.

Since commit 0f7ddcc1bff1 ("iio:adc:ad799x: Write default config on probe
and reset alert status on probe") the error path is wrong since it
leaves the vref regulator on. Fix this by disabling both regulators.

Fixes: 0f7ddcc1bff1 ("iio:adc:ad799x: Write default config on probe and reset alert status on probe")
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-17 13:45:12 -07:00
Andreas Klinger
2cb6f0417e iio: adc: hx711: fix bug in sampling of data
commit 4043ecfb5fc4355a090111e14faf7945ff0fdbd5 upstream.

Fix bug in sampling function hx711_cycle() when interrupt occures while
PD_SCK is high. If PD_SCK is high for at least 60 us power down mode of
the sensor is entered which in turn leads to a wrong measurement.

Switch off interrupts during a PD_SCK high period and move query of DOUT
to the latest point of time which is at the end of PD_SCK low period.

This bug exists in the driver since it's initial addition. The more
interrupts on the system the higher is the probability that it happens.

Fixes: c3b2fdd0ea7e ("iio: adc: hx711: Add IIO driver for AVIA HX711")
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-17 13:45:12 -07:00
Olivier Moysan
0ae0c43abc iio: adc: stm32-dfsdm: fix data type
commit c6013bf50e2a2a94ab3d012e191096432aa50c6f upstream.

Fix the data type as DFSDM raw output is complements 2,
24bits left aligned in a 32-bit register.
This change does not affect AUDIO path
- Set data as signed for IIO (as for AUDIO)
- Set 8 bit right shift for IIO.
The 8 LSBs bits of data contains channel info and are masked.

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Fixes: e2e6771c6462 ("IIO: ADC: add STM32 DFSDM sigma delta ADC support")
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-19 09:09:40 +02:00
Arnd Bergmann
5026932adb iio: adc: gyroadc: fix uninitialized return code
[ Upstream commit 90c6260c1905a68fb596844087f2223bd4657fee ]

gcc-9 complains about a blatant uninitialized variable use that
all earlier compiler versions missed:

drivers/iio/adc/rcar-gyroadc.c:510:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]

Return -EINVAL instead here and a few lines above it where
we accidentally return 0 on failure.

Cc: stable@vger.kernel.org
Fixes: 059c53b32329 ("iio: adc: Add Renesas GyroADC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-16 08:22:22 +02:00
Krzysztof Kozlowski
0d7f329e24 iio: adc: exynos-adc: Use proper number of channels for Exynos4x12
[ Upstream commit 103cda6a3b8d2c10d5f8cd7abad118e9db8f4776 ]

Exynos4212 and Exynos4412 have only four ADC channels so using
"samsung,exynos-adc-v1" compatible (for eight channels ADCv1) on them is
wrong.  Add a new compatible for Exynos4x12.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-16 08:22:06 +02:00
Jonathan Bakker
7f588a7262 iio: adc: exynos-adc: Add S5PV210 variant
[ Upstream commit 882bf52fdeab47dbe991cc0e564b0b51c571d0a3 ]

S5PV210's ADC variant is almost the same as v1 except that it has 10
channels and doesn't require the pmu register

Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-09-16 08:22:05 +02:00
Jacopo Mondi
367d103a4a iio: adc: max9611: Fix temperature reading in probe
commit b9ddd5091160793ee9fac10da765cf3f53d2aaf0 upstream.

The max9611 driver reads the die temperature at probe time to validate
the communication channel. Use the actual read value to perform the test
instead of the read function return value, which was mistakenly used so
far.

The temperature reading test was only successful because the 0 return
value is in the range of supported temperatures.

Fixes: 69780a3bbc0b ("iio: adc: Add Maxim max9611 ADC driver")
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-25 10:47:59 +02:00
Joe Perches
fcab378301 iio: adc: max9611: Fix misuse of GENMASK macro
commit ae8cc91a7d85e018c0c267f580820b2bb558cd48 upstream.

Arguments are supposed to be ordered high then low.

Signed-off-by: Joe Perches <joe@perches.com>
Fixes: 69780a3bbc0b ("iio: adc: Add Maxim max9611 ADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-16 10:12:37 +02:00
Fabien Dessenne
b59f7650a5 iio: adc: stm32-dfsdm: missing error case during probe
[ Upstream commit d2fc0156963cae8f1eec8e2dd645fbbf1e1c1c8e ]

During probe, check the devm_ioremap_resource() error value.
Also return the devm_clk_get() error value instead of -EINVAL.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31 07:26:56 +02:00
Fabien Dessenne
302e4cdca1 iio: adc: stm32-dfsdm: manage the get_irq error case
[ Upstream commit 3e53ef91f826957dec013c47707ffc1bb42b42d7 ]

During probe, check the "get_irq" error value.

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>
Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-07-31 07:26:56 +02:00
Sean Nyekjaer
5dede5c9e6 iio: adc: ti-ads8688: fix timestamp is not updated in buffer
commit e6d12298310fa1dc11f1d747e05b168016057fdd upstream.

When using the hrtimer iio trigger timestamp isn't updated.
If we use iio_get_time_ns it is updated correctly.

Fixes: 2a86487786b5c ("iio: adc: ti-ads8688: add trigger and buffer support")
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-09 09:17:15 +02:00
Justin Chen
ef8e5a7840 iio: adc: ti-ads7950: Fix improper use of mlock
[ Upstream commit abbde2792999c9ad3514dd25d7f8d9a96034fe16 ]

Indio->mlock is used for protecting the different iio device modes.
It is currently not being used in this way. Replace the lock with
an internal lock specifically used for protecting the SPI transfer
buffer.

Signed-off-by: Justin Chen <justinpopo6@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31 06:46:25 -07:00