kernel/linux.git/include/linux/iio/buffer.h, branch v6.6.132

iio: Add output buffer support

2021-10-19T07:30:44+00:00

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 Signed-off-by: Lars-Peter Clausen Co-developed-by: Alexandru Ardelean Signed-off-by: Alexandru Ardelean Signed-off-by: Mihail Chindris Link: https://lore.kernel.org/r/20211007080035.2531-2-mihail.chindris@analog.com Signed-off-by: Jonathan Cameron

iio: core: Introduce iio_push_to_buffers_with_ts_unaligned()

2021-10-19T07:29:22+00:00

Whilst it is almost always possible to arrange for scan data to be read directly into a buffer that is suitable for passing to iio_push_to_buffers_with_timestamp(), there are a few places where leading data needs to be skipped over. For these cases introduce a function that will allocate an appropriate sized and aligned bounce buffer (if not already allocated) and copy the unaligned data into that before calling iio_push_to_buffers_with_timestamp() on the bounce buffer. We tie the lifespace of this buffer to that of the iio_dev.dev which should ensure no memory leaks occur. Signed-off-by: Jonathan Cameron Reviewed-by: Nuno Sá Link: https://lore.kernel.org/r/20210613151039.569883-2-jic23@kernel.org

iio: buffer: introduce support for attaching more IIO buffers

2021-03-11T20:47:05+00:00

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 Link: https://lore.kernel.org/r/20210215104043.91251-20-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron

iio: buffer: remove iio_buffer_set_attrs() helper

2020-11-21T14:53:37+00:00

The iio_buffer_set_attrs() is no longer used in the drivers, so it can be removed now. Signed-off-by: Alexandru Ardelean Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20200929125949.69934-10-alexandru.ardelean@analog.com Signed-off-by: Jonathan Cameron

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

2019-06-19T15:09:55+00:00

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 Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

iio:buffer.h - split into buffer.h and buffer_impl.h

2017-01-10T19:54:55+00:00

buffer.h supplies everything needed for devices using buffers. buffer_impl.h supplies access to the internals as needed to write a buffer implementation. This was really motivated by the mess that turned up in the kernel-doc documentation pulled in by the new sphinx docs. It made it clear that our logical separations in headers were generally terrible. The buffer case was easy to sort out without greatly effecting drivers so here it is. Signed-off-by: Jonathan Cameron Reviewed-by: Lars-Peter Clausen

iio:buffer: Push implementation of iio_device_attach_buffer into .c file

2017-01-10T19:54:54+00:00

This is a precursor to the splitting of buffer.h into parts relevant to buffer implementation vs those for devices using buffers. struct buffer is about to become opaque as far as the header is concerned. Signed-off-by: Jonathan Cameron Reviewed-by: Lars-Peter Clausen

iio:buffer:iio_push_to_buffers_with_timestamp fix kernel-doc.

2017-01-10T19:54:52+00:00

Wrong start of kernel doc comment /* -> /** Signed-off-by: Jonathan Cameron Reviewed-by: Lars-Peter Clausen

iio:buffers: Push some docs down into the .c file.

2017-01-10T19:54:51+00:00

Ancient legacy of me doing it wrong which it is nice to clear up whilst we are here. Signed-off-by: Jonathan Cameron Reviewed-by: Lars-Peter Clausen

iio:buffer: Stop exporting iio_scan_mask_query

2017-01-10T19:54:51+00:00

Nothing uses it outside of core code. Signed-off-by: Jonathan Cameron Reviewed-by: Lars-Peter Clausen