We may want to get rid of the iio_priv_to_dev() helper. The reason is that
we will hide some of the members of the iio_dev structure (to prevent
drivers from accessing them directly), and that will also mean hiding the
implementation of the iio_priv_to_dev() helper inside the IIO core.
Hiding the implementation of iio_priv_to_dev() implies that some fast-paths
may not be fast anymore, so a general idea is to try to get rid of the
iio_priv_to_dev() altogether.
The iio_priv() helper won't be affected by the rework, as the iio_dev
struct will keep a reference to the private information.
For this driver, not using iio_priv_to_dev(), means reworking some paths to
pass the iio device and using iio_priv() to access the private information,
and also keeping a reference to the iio device for some quirky paths.
One [quirky] path is the at91_adc_workq_handler() which requires the IIO
device & the state struct to push to buffers.
Since this requires the back-ref to the IIO device, the
at91_adc_touch_pos() also uses it. This simplifies the patch a bit. The
information required in this function is mostly for debugging purposes.
Replacing it with a reference to the IIO device would have been a slightly
bigger change, which may not be worth it (for just the debugging purpose
and given that we need the back-ref to the IIO device anyway).
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
All devices using a triggered buffer need to attach and detach the trigger
to the device in order to properly work. Instead of doing this in each and
every driver by hand move this into the core.
At this point in time, all drivers should have been resolved to
attach/detach the poll-function in the same order.
This patch removes all explicit calls of iio_triggered_buffer_postenable()
& iio_triggered_buffer_predisable() in all drivers, since the core handles
now the pollfunc attach/detach.
The more peculiar change is for the 'at91-sama5d2_adc' driver, since it's
not immediately obvious that removing the hooks doesn't break anything.
Eugen was able to test on at91-sama5d2-adc driver, sama5d2-xplained board.
All seems to be fine.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Tested-by: Eugen Hristev <eugen.hristev@microchip.com> #for at91-sama5d2-adc
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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>
The iio_triggered_buffer_{predisable,postenable} functions attach/detach
poll functions.
In most cases the iio_triggered_buffer_postenable() should be called first
to attach the poll function, and then the driver can init the data to be
triggered.
In this case it's the other way around: the DMA code should be initialized
before the attaching the poll function and the reverse should be done when
un-initializing.
To make things easier when removing the iio_triggered_buffer_postenable() &
iio_triggered_buffer_predisable() functions from the IIO core API, the DMA
code has been moved into preenable() for init, and postdisable() for
uninit.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Reviewed-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This change moves the logic to check if the current channel is the
touchscreen channel to a separate helper.
This reduces some code duplication, but the main intent is to re-use this
in the next patches.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Reviewed-by: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This change will allow the at91-sama5d2_adc driver to use other triggers
than it's own.
In particular, tested with the sysfs trigger.
To be able to achieve this functionality, some changes were required:
1) Do not enable/disable channels when enabling/disabling the trigger.
This is because the trigger is enabled/disabled only for our trigger
(obviously). We need channels enabled/disabled regardless of what trigger is
being used.
2) Cope with DMA : DMA cannot be used when using another type of trigger.
Other triggers work through pollfunc, so we get polled anyway on every trigger.
Thus we have to obtain data at every trigger.
3) When to start conversion? The usual pollfunc (store time from subsystem)
would be in hard irq and this would be a good way, but current iio subsystem
recommends to have it in the threaded irq. Thus adding software start
code in this handler.
4) Buffer config: we need to setup buffer regardless of our own device's
trigger. We may get one attached later.
5) IRQ handling: we use our own device IRQ only if it's our own trigger
and we do not use DMA . If we use DMA, we use the DMA controller's IRQ.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
It can happen that on IRQ trigger, not all conversions are done if
we are enabling multiple channels.
The IRQ is triggered on first EOC (end of channel), but it can happen
that not all channels are done. This leads into erroneous reports to
userspace (zero values or previous values).
To solve this, in trigger handler, check if the mask of done channels
is the same as the mask of active scan channels.
If it's the same, proceed and push to buffers. Otherwise, use usleep
to sleep until the conversion is done or we timeout.
Normally, it should happen that in a short time fashion, all channels are
ready, since the first IRQ triggered.
If a hardware fault happens (for example the clock suddently dissappears),
the handler will not be completed, in which case we do not report anything to
userspace anymore.
Also, change from using the EOC interrupts to DRDY interrupt.
This helps with the fact that not 'n' interrupt statuses are enabled,
each being able to trigger an interrupt, and instead only data ready
interrupt can wake up the CPU. Like this, when data is ready, check in
handler which and how many channels are done. While the DRDY is raised,
other IRQs cannot occur. Once the channel data is being read, we ack the
IRQ and finish the conversion.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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: 5e1a1da0f8 ("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>
dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.
The dma_request_chan() is the standard API to request slave channel,
clients should be moved away from the legacy API to allow us to retire
them.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cleans up the sparse warning:
CHECK drivers/iio/adc/at91-sama5d2_adc.c
drivers/iio/adc/at91-sama5d2_adc.c:1486:31: warning: Using plain integer as NULL pointer
drivers/iio/adc/at91-sama5d2_adc.c:1509:31: warning: Using plain integer as NULL pointer
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Eugen Hristev <eugen.hristev@microchip.com>
Based on 1 normalized pattern(s):
this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 285 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This code is problematic because we're supposed to be writing an int but
we instead write to only the high 16 bits. This doesn't work on big
endian systems, and there is a potential that the bottom 16 bits are
used without being initialized.
Fixes: 23ec2774f1 ("iio: adc: at91-sama5d2_adc: add support for position and pressure channels")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Tested-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This implements oversampling support for the SAMA5d2 ADC device.
Enabling oversampling : OSR can improve resolution from 12 bits to
13 or 14 bits.
Changing the channel specification to have 14 bits, and we shift the value
1 bit to the left if we have oversampling for just one extra bit, and two
bits to the left if we have no oversampling (old support).
From this commit on, the converted values for all the voltage channels
change to 14 bits real data, with most insignificant two bits always zero
if oversampling is not enabled.
sysfs object oversampling_ratio has been enabled and
oversampling_ratio_available will list possible values (1 or 4 or 16) having
1 as default (no oversampling, 1 sample for each conversion).
Special care was required for the triggered buffer scenario (+ DMA), to
adjust the values accordingly.
Touchscreen measurements supported by this driver are not affected by
oversampling, they are still on 12 bits (scale handing is already included
in the driver).
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This implements the support for position and pressure for the included
touchscreen support in the SAMA5D2 SOC ADC block.
Two position channels are added and one for pressure.
They can be read in raw format, or through a buffer.
A normal use case is for a consumer driver to register a callback buffer
for these channels.
When the touchscreen channels are in the active scan mask,
the driver will start the touchscreen sampling and push the data to the
buffer.
Some parts of this patch are based on initial original work by
Mohamed Jamsheeth Hajanajubudeen and Bandaru Venkateswara Swamy
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
When iterating through the channels, the index in the array is not the
scan index. Added an xlate function to translate to the proper index.
The result of the bug is that the channel array is indexed with a wrong index,
thus instead of the proper channel, we access invalid memory, which may
lead to invalid results and/or corruption.
This will be used also for devicetree channel xlate.
Fixes: 5e1a1da0f ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support")
Fixes: 073c66201 ("iio: adc: at91-sama5d2_adc: add support for DMA")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Need to acknowledge DRDY irq in direct mode/ software
triggered mode. Otherwise, on the next conversion, overrun
flag will be raised, which is not a correct state.
This doesn't affect the functionality, but will generate
possible incorrect overrun reports.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Added support for DMA transfers. The implementation uses the user watermark
to decide whether DMA will be used or not. For watermark 1, DMA will not be
used. If watermark is bigger, DMA will be used.
Sysfs attributes are created to indicate whether the DMA is used,
with hwfifo_enabled, and the current DMA watermark is readable
in hwfifo_watermark. Minimum and maximum values are in hwfifo_watermark_min
and hwfifo_watermark_max.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This fix allows platforms to probe correctly even if the
trigger edge property is missing. The hardware trigger
will no longer be registered in the sybsystem
Preserves backwards compatibility with the support that
was in the driver before the hardware trigger.
https://storage.kernelci.org/mainline/master/v4.14-rc2-255-g74d83ec2b734/arm/sama5_defconfig/lab-free-electrons/boot-at91-sama5d2_xplained.txt
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Fixes: 5e1a1da0f ("iio: adc: at91-sama5d2_adc: add hw trigger and buffer support")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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>
Making the const array startup_lookup static rather having it on the
stack saves 69 bytes. Add in missing int specifier to clean up a
checkpatch warning.
Before:
text data bss dec hex filename
10297 2800 128 13225 33a9 drivers/iio/adc/at91-sama5d2_adc.o
After:
text data bss dec hex filename
10140 2888 128 13156 3364 drivers/iio/adc/at91-sama5d2_adc.o
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Added support for suspend/resume functionality for the ADC IP
in sama5d2 SoC.
In order to enter Suspend to ram mode (backup + self refresh mode for
memory), in which the ADC IP is no longer powered, we need to reset the
pins to default state, for the scenario when they are also used for I2C
bus to communicate with the PMIC.
On resume, we need to reconfigure the ADC IP registers and reconfigure the
trigger registers in the case when the suspend procedure is done while
sysfs has the buffer and trigger enabled.
In the case the suspend happens exactly during a software triggered
conversion, the request will time out, because we reset and power down
the ADC.
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Added support for the external hardware trigger on pin ADTRG,
integrated the three possible edges into the driver
and created buffer management for data retrieval
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Add signed differential channels and update the voltage scale for
differential conversions.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Do not erase previous configuration of the mode register when setting
the sampling frequency.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Use var type for sizeof argument instead of the struct name.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
vref_uv has to be an int.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This driver supports the new version of the Atmel ADC device introduced
with the SAMA5D2 SoC family.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
