Commit graph

24 commits

Author SHA1 Message Date
Yue Haibing
4eaf928622 iio: Remove unused declarations
Commit 0f3a8c3f34 ("iio: Add support for creating IIO devices via configfs")
declared but never implemented iio_sw_device_type_configfs_{un}register().
Commit b662f809d4 ("iio: core: Introduce IIO software triggers") declared but
never implemented iio_sw_trigger_type_configfs_{un}register().
Commit a3e0b51884 ("iio: accel: add support for FXLS8962AF/FXLS8964AF accelerometers")
declared but never implemented fxls8962af_core_remove().
Commit 8dedcc3eee ("iio: core: centralize ioctl() calls to the main chardev")
declared but never implemented iio_device_ioctl().

Commit d430f3c36c ("iio: imu: inv_mpu6050: Use regmap instead of i2c specific functions")
removed inv_mpu6050_write_reg() but not its declaration.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20230811095701.35372-1-yuehaibing@huawei.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-09-12 10:42:03 +01:00
Lars-Peter Clausen
3c33b7b826 iio: Mark iio_device_type as const
The iio_device_type struct is never modified, mark it as const. This allows
it to be placed in a read-only memory section, which will protect against
accidental or deliberate modification.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20211031080421.2086-1-lars@metafoo.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-11-17 17:51:35 +00:00
Mihail Chindris
9eeee3b0bf iio: Add output buffer support
Currently IIO only supports buffer mode for capture devices like ADCs. Add
support for buffered mode for output devices like DACs.

The output buffer implementation is analogous to the input buffer
implementation. Instead of using read() to get data from the buffer write()
is used to copy data into the buffer.

poll() with POLLOUT will wakeup if there is space available.

Drivers can remove data from a buffer using iio_pop_from_buffer(), the
function can e.g. called from a trigger handler to write the data to
hardware.

A buffer can only be either a output buffer or an input, but not both. So,
for a device that has an ADC and DAC path, this will mean 2 IIO buffers
(one for each direction).

The direction of the buffer is decided by the new direction field of the
iio_buffer struct and should be set after allocating and before registering
it.

Co-developed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Co-developed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Mihail Chindris <mihail.chindris@analog.com>
Link: https://lore.kernel.org/r/20211007080035.2531-2-mihail.chindris@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-10-19 08:30:44 +01:00
Alexandru Ardelean
218bc53dc7 iio: buffer: fix use-after-free for attached_buffers array
Thanks to Lars for finding this.
The free of the 'attached_buffers' array should be done as late as
possible. This change moves it to iio_buffers_put(), which looks like
the best place for it, since it takes place right before the IIO device
data is free'd.
The free of this array will be handled by calling iio_device_free().
The iio_buffers_put() function is renamed to iio_device_detach_buffers()
since the role of this function changes a bit.

It looks like this issue was ocurring on the error path of
iio_buffers_alloc_sysfs_and_mask() and in
iio_buffers_free_sysfs_and_mask()

Added a comment in the doc-header of iio_device_attach_buffer() to
mention how this will be free'd in case anyone is reading the code
and becoming confused about it.

Fixes: ee708e6baa ("iio: buffer: introduce support for attaching more IIO buffers")
Reported-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Link: https://lore.kernel.org/r/20210307185444.32924-1-ardeleanalex@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-25 19:13:51 +00:00
Alexandru Ardelean
f73f7f4da5 iio: buffer: add ioctl() to support opening extra buffers for IIO device
With this change, an ioctl() call is added to open a character device for a
buffer. The ioctl() number is 'i' 0x91, which follows the
IIO_GET_EVENT_FD_IOCTL ioctl.

The ioctl() will return an FD for the requested buffer index. The indexes
are the same from the /sys/iio/devices/iio:deviceX/bufferY (i.e. the Y
variable).

Since there doesn't seem to be a sane way to return the FD for buffer0 to
be the same FD for the /dev/iio:deviceX, this ioctl() will return another
FD for buffer0 (or the first buffer). This duplicate FD will be able to
access the same buffer object (for buffer0) as accessing directly the
/dev/iio:deviceX chardev.

Also, there is no IIO_BUFFER_GET_BUFFER_COUNT ioctl() implemented, as the
index for each buffer (and the count) can be deduced from the
'/sys/bus/iio/devices/iio:deviceX/bufferY' folders (i.e the number of
bufferY folders).

Used following C code to test this:
-------------------------------------------------------------------

 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/ioctl.h>
 #include <fcntl.h"
 #include <errno.h>

 #define IIO_BUFFER_GET_FD_IOCTL      _IOWR('i', 0x91, int)

int main(int argc, char *argv[])
{
        int fd;
        int fd1;
        int ret;

        if ((fd = open("/dev/iio:device0", O_RDWR))<0) {
                fprintf(stderr, "Error open() %d errno %d\n",fd, errno);
                return -1;
        }

        fprintf(stderr, "Using FD %d\n", fd);

        fd1 = atoi(argv[1]);

        ret = ioctl(fd, IIO_BUFFER_GET_FD_IOCTL, &fd1);
        if (ret < 0) {
                fprintf(stderr, "Error for buffer %d ioctl() %d errno %d\n", fd1, ret, errno);
                close(fd);
                return -1;
        }

        fprintf(stderr, "Got FD %d\n", fd1);

        close(fd1);
        close(fd);

        return 0;
}
-------------------------------------------------------------------

Results are:
-------------------------------------------------------------------
 # ./test 0
 Using FD 3
 Got FD 4

 # ./test 1
 Using FD 3
 Got FD 4

 # ./test 2
 Using FD 3
 Got FD 4

 # ./test 3
 Using FD 3
 Got FD 4

 # ls /sys/bus/iio/devices/iio\:device0
 buffer  buffer0  buffer1  buffer2  buffer3  dev
 in_voltage_sampling_frequency  in_voltage_scale
 in_voltage_scale_available
 name  of_node  power  scan_elements  subsystem  uevent
-------------------------------------------------------------------

iio:device0 has some fake kfifo buffers attached to an IIO device.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-21-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-11 20:47:05 +00:00
Alexandru Ardelean
ee708e6baa iio: buffer: introduce support for attaching more IIO buffers
With this change, calling iio_device_attach_buffer() will actually attach
more buffers.
Right now this doesn't do any validation of whether a buffer is attached
twice; maybe that can be added later (if needed). Attaching a buffer more
than once should yield noticeably bad results.

The first buffer is the legacy buffer, so a reference is kept to it.

At this point, accessing the data for the extra buffers (that are added
after the first one) isn't possible yet.

The iio_device_attach_buffer() is also changed to return an error code,
which for now is -ENOMEM if the array could not be realloc-ed for more
buffers.
To adapt to this new change iio_device_attach_buffer() is called last in
all place where it's called. The realloc failure is a bit difficult to
handle during un-managed calls when unwinding, so it's better to have this
as the last error in the setup_buffer calls.

At this point, no driver should call iio_device_attach_buffer() directly,
it should call one of the {devm_}iio_triggered_buffer_setup() or
devm_iio_kfifo_buffer_setup() or devm_iio_dmaengine_buffer_setup()
functions. This makes iio_device_attach_buffer() a bit easier to handle.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-20-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-11 20:47:05 +00:00
Alexandru Ardelean
be24dcb113 iio: core: wrap iio device & buffer into struct for character devices
In order to keep backwards compatibility with the current chardev
mechanism, and in order to add support for multiple buffers per IIO device,
we need to pass both the IIO device & IIO buffer to the chardev.

This is particularly needed for the iio_buffer_read_outer() function, where
we need to pass another buffer object than 'indio_dev->buffer'.

Since we'll also open some chardevs via anon inodes, we can pass extra
buffers in that function by assigning another object to the
iio_dev_buffer_pair object.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-17-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-11 20:47:04 +00:00
Alexandru Ardelean
3e3d11b2e4 iio: add reference to iio buffer on iio_dev_attr
This change adds a reference to a 'struct iio_buffer' object on the
iio_dev_attr object. This way, we can use the created iio_dev_attr objects
on per-buffer basis (since they're allocated anyway).

A minor downside of this change is that the number of parameters on
__iio_add_chan_devattr() grows by 1. This looks like it could do with a bit
of a re-think.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-14-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-11 20:47:04 +00:00
Alexandru Ardelean
32f171724e iio: core: rework iio device group creation
Up until now, the device groups that an IIO device had were limited to 6.
Two of these groups would account for buffer attributes (the buffer/ and
scan_elements/ directories).

Since we want to add multiple buffers per IIO device, this number may not
be enough, when adding a second buffer. So, this change reallocates the
groups array whenever an IIO device group is added, via a
iio_device_register_sysfs_group() helper.

This also means that the groups array should be assigned to
'indio_dev.dev.groups' really late, right before {cdev_}device_add() is
called to do the entire setup.
And we also must take care to free this array when the sysfs resources are
being cleaned up.

With this change we can also move the 'groups' & 'groupcounter' fields to
the iio_dev_opaque object. Up until now, this didn't make a whole lot of
sense (especially since we weren't sure how multibuffer support would look
like in the end).
But doing it now kills one birds with one stone.

An alternative, would be to add a configurable Kconfig symbol
CONFIG_IIO_MAX_BUFFERS_PER_DEVICE (or something like that) and compute a
static maximum of the groups we can support per IIO device. But that would
probably annoy a few people since that would make the system less
configurable.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20210215104043.91251-11-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-11 20:47:03 +00:00
Alexandru Ardelean
8dedcc3eee iio: core: centralize ioctl() calls to the main chardev
The aim of this is to improve a bit the organization of ioctl() calls in
IIO core. Currently the chardev is split across IIO core sub-modules/files.
The main chardev has to be able to handle ioctl() calls, and if we need to
add buffer ioctl() calls, this would complicate things.

The 'industrialio-core.c' file will provide a 'iio_device_ioctl()' which
will iterate over a list of ioctls registered with the IIO device. These
can be event ioctl() or buffer ioctl() calls, or something else.

Each ioctl() handler will have to return a IIO_IOCTL_UNHANDLED code (which
is positive 1), if the ioctl() did not handle the call in any. This
eliminates any potential ambiguities about negative error codes, which
should fail the call altogether.

If any ioctl() returns 0, it was considered that it was serviced
successfully and the loop will exit.

This change also moves the handling of the IIO_GET_EVENT_FD_IOCTL command
inside 'industrialio-event.c', where this is better suited.

This patch is a combination of 2 other patches from an older series:
Patch 1: iio: core: add simple centralized mechanism for ioctl() handlers
  Link: https://lore.kernel.org/linux-iio/20200427131100.50845-6-alexandru.ardelean@analog.com/
Patch 2: iio: core: use new common ioctl() mechanism
  Link: https://lore.kernel.org/linux-iio/20200427131100.50845-7-alexandru.ardelean@analog.com/

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924084155.99406-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-11-14 15:31:25 +00:00
Lars-Peter Clausen
f6d4033d2a iio: buffer: rename 'read_first_n' callback to 'read'
It is implied that 'read' will read the first n bytes and not e.g. bytes
only from offsets within the buffer that are a prime number.

This change is non-functional, mostly just a rename.
A secondary intent with this patch is to make room later to add a write
callback.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2019-12-29 15:20:09 +00:00
Thomas Gleixner
d2912cb15b 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>
2019-06-19 17:09:55 +02:00
Al Viro
afc9a42b74 the rest of drivers/*: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:06:58 -05:00
Gregor Boirie
bc2b7dab62 iio:core: timestamping clock selection support
Adds a new per-device sysfs attribute "current_timestamp_clock" to allow
userspace to select a particular POSIX clock for buffered samples and
events timestamping.

Following clocks, as listed in clock_gettime(2), are supported:
CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW,
CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_COARSE, CLOCK_BOOTTIME and
CLOCK_TAI.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Acked-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-06-30 19:41:38 +01:00
Lars-Peter Clausen
3e1b6c95b9 iio: Move buffer registration to the core
Originally device and buffer registration were kept as separate operations
in IIO to allow to register two distinct sets of channels for buffered and
non-buffered operations. This has since already been further restricted and
the channel set registered for the buffer needs to be a subset of the
channel set registered for the device. Additionally the possibility to not
have a raw (or processed) attribute for a channel which was registered for
the device was added a while ago. This means it is possible to not register
any device level attributes for a channel even if it is registered for the
device. Also if a channel's scan_index is set to -1 and the channel is
registered for the buffer it is ignored.

So in summary it means it is possible to register the same channel array for
both the device and the buffer yet still end up with distinctive sets of
channels for both of them. This makes the argument for having to have to
manually register the channels for both the device and the buffer invalid.
Considering that the vast majority of all drivers want to register the same
set of channels for both the buffer and the device it makes sense to move
the buffer registration into the core to avoid some boiler-plate code in the
device driver setup path.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-12-12 12:28:31 +00:00
Srinivas Pandruvada
9fbfb4b37e IIO: core: Introduce read_raw_multi
This callback is introduced to overcome some limitations of existing
read_raw callback. The functionality of both existing read_raw and
read_raw_multi is similar, both are used to request values from the
device. The current read_raw callback allows only two return values.
The new read_raw_multi allows returning multiple values. Instead of
passing just address of val and val2, it passes length and pointer
to values. Depending on the type and length of passed buffer, iio
client drivers can return multiple values.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-04-29 22:05:32 +01:00
Lars-Peter Clausen
3661f3f5e9 iio: Factor IIO value formating into its own function
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-10-12 12:23:33 +01:00
Lars-Peter Clausen
84088ebd14 iio: Add a helper to free a list of IIO device attributes
We have the same code to free a IIO device attribute list in multiple place.
This patch adds a new helper function to take care of this and replaces the
custom instances with a call to the helper function. Note that we do not need to
call list_del() for each of the list items since we will never look at any of
the list items nor the list itself again.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-10-12 12:17:34 +01:00
Lars-Peter Clausen
d2f0a48f36 iio: Wakeup poll and blocking reads when the device is unregistered
Once the device has been unregistered there won't be any new data no matter how
long a userspace application waits, so we might as well wake them up and let
them know.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-10-12 12:05:36 +01:00
Greg Kroah-Hartman
e2aad1d571 Merge 3.12-rc2 into staging-next.
This resolves the merge problem with two iio drivers that Stephen
Rothwell pointed out.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-25 08:59:04 -07:00
Lars-Peter Clausen
a87c82e454 iio: Stop sampling when the device is removed
Make sure to stop sampling when the device is removed, otherwise it will
continue to sample forever.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-09-21 12:36:30 +01:00
Jonathan Cameron
3704432fb1 iio: refactor info mask and ext_info attribute creation.
Introduce an enum to specify whether the attribute is separate or
shared.

Factor out the bitmap handling for loop into a separate function.

Tidy up error handling and add a NULL assignment to squish a false
positive warning from GCC.

Change ext_info shared type from boolean to enum and update in all
drivers.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
2013-09-15 17:43:20 +01:00
Guenter Roeck
17d82b47a2 iio: Add OF support
Provide bindings and parse OF data during initialization.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2013-03-16 10:17:59 +00:00
Jonathan Cameron
a980e04609 IIO: Move the core files to drivers/iio
Take the core support + the kfifo buffer implentation out of
staging.  Whilst we are far from done in improving this subsystem
it is now at a stage where the userspae interfaces (provided by
the core) can be considered stable.

Drivers will follow over a longer time scale.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-25 11:11:38 -07:00
Renamed from drivers/staging/iio/iio_core.h (Browse further)