Currently AD7124-8 driver cannot use more than 8 IIO channels
because it was assigning the channel configurations bijectively
to channels specified in the device-tree. This is not possible
to do when using more than 8 channels as AD7124-8 has only 8
configuration registers.
To allow the user to use all channels at once the driver
will keep in memory configurations for all channels but
will program only 8 of them at a time on the device.
If multiple channels have the same configuration, only
one configuration register will be used. If there
are more configurations than available registers only
the last 8 used configurations will be allowed to exist
on the device in a LRU fashion.
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20210311091154.47785-2-alexandru.tachici@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This patch fixes the device name typo.
Fixes: 951ad47003 ("iio: adc: ad7124: move chip ID & name on the chip_info table")
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200902134222.28357-1-mircea.caprioru@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This change does the following:
* removes the SPI device table in favor of the OF device table
* adds 'name' && 'chip_id' fields to chip_info
* implements chip ID & silicon revision checking; the device ID for
AD7124-4 is 0x0, so just checking that value can be useless;
but at least the silicon revision isn't 0, so a non-zero value can be
used to check that "a" device is on the SPI bus; it's probably the best
way to narrow it down to one of the 2 AD7124 chip IDs
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
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>
This patch adds the posibility do read and write registers from userspace
using the kernel debug direct register access option.
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This patch adds the LOW_PASS_FILTER_3DB_FREQUENCY attribute
in iio_chan_spec for each channel. The used filters are sinc3
or sinc4. The filter type with the highest output data rate
is used when setting a low pass frequency in the channel's sysfs.
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Ad7124 data-sheet specifies that the falling edge
of the DOUT line should be used for an interrupt.
The current irq flag (IRQF_TRIGGER_LOW) used will
cause unwanted behaviour. When enabling the interrupt
it will fire once because the DOUT line is already low.
This will make the driver to read an unfinished conversion
from the chip.
This patch sets the irq type to the one specified in
the data-sheet.
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Before this patch the ad_sigma_delta implementation hardcoded
the irq trigger type to low, assuming that all Sigma-Delta ADCs
have the same interrupt-type.
This patch allows all drivers using the ad_sigma_delta layer to set the
irq trigger type to the one specified in the datasheet.
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This patch fixes device tree channel configuration.
ad7124 driver reads channels configuration from the device tree.
It expects to find channel specifications as child nodes.
Before this patch ad7124 driver assumed that the child nodes are parsed
by for_each_available_child_of_node in the order 0,1,2,3...
This is wrong and the real order of the children can be seen by running:
dtc -I fs /sys/firmware/devicetree/base on the machine.
For example, running this on an rpi 3B+ yields the real
children order: 4,2,0,7,5,3,1,6
Before this patch the driver assigned the channel configuration
like this:
- 0 <- 4
- 1 <- 2
- 2 <- 0
........
For example, the symptoms can be observed by connecting the 4th channel
to a 1V tension and then reading the in_voltage0-voltage19_raw sysfs
(multiplied of course by the scale) one would see that channel 0
measures 1V and channel 4 measures only noise.
Now the driver uses the reg property of each child in order to
correctly identify to which channel the parsed configuration
belongs to.
Fixes b3af341bbd: ("iio: adc: Add ad7124 support")
Signed-off-by: Alexandru Tachici <alexandru.tachici@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>
When the internal reference was selected by a channel it was not enabled.
This patch fixes that and enables it.
Fixes: b3af341bbd ("iio: adc: Add ad7124 support")
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This patch changes the channel configuration member of the device
structure from a fixed size array to a dynamic allocated one with a size
equal to the number of channels specified in the device tree. This will
ensure a more flexibility for compatible devices.
Ex. ad7124-4 - can have 4 differential or 8 pseudo-differential channels
ad7124-8 - can have 8 differential or 16 pseudo-differential channels
Also the device can suspport any other combination of differential and
pseudo-differential channels base on the physical number of inputs
available.
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This patch adds the option to enable the buffered mode for positive and
negative inputs. Each option can be enabled independently.
In buffered mode, the input channel feeds into a high impedance input stage
of the buffer amplifier. Therefore, the input can tolerate significant
source impedances and is tailored for direct connection to external
resistive type sensors such as strain gages or RTDs.
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The driver limits the user to use only 4/8 differential inputs, but this
device has the option to use pseudo-differential channels. This will
increase the number of channels to be equal with the number of inputs so 8
channels for ad7124-4 and 16 for ad7124-8.
This patch removes the check between channel nodes and num_inputs value.
Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
A return statement is indented one level too deeply; clean this
up by removing a tab.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
The ad7124-4 and ad7124-8 are a family of 4 and 8 channel sigma-delta ADCs
with 24-bit precision and reference.
Three power modes are available which in turn affect the output data rate:
* Full power: 9.38 SPS to 19,200 SPS
* Mid power: 2.34 SPS to 4800 SPS
* Low power: 1.17 SPS to 2400 SPS
The ad7124-4 can be configured to have four differential inputs, while
ad7124-8 can have 8. Moreover, ad7124 also supports per channel
configuration. Each configuration consists of gain, reference source,
output data rate and bipolar/unipolar configuration.
Datasheets:
Link: http://www.analog.com/media/en/technical-documentation/data-sheets/AD7124-4.pdf
Link: http://www.analog.com/media/en/technical-documentation/data-sheets/ad7124-8.pdf
Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
