linux.git/drivers/iio/buffer/industrialio-buffer-dmaengine.c, branch v5.6

iio: buffer: rename 'read_first_n' callback to 'read'

2019-12-29T15:20:09+00:00

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 
Signed-off-by: Alexandru Ardelean 
Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Report buffer length requirements

2019-12-29T15:20:09+00:00

The dmaengine buffer has some length alignment requirements that can differ
from platform to platform. If the length alignment requirements are not met
unexpected behavior like dropping of samples can occur.

Currently these requirements are not reported and applications need to know
the requirements of the platform by some out-of-band means.

Add a new buffer attribute that reports the length alignment requirements
called `length_align_bytes`. The reported length alignment is in bytes that
means the buffer length alignment in sample sets depends on the number of
enabled channels and the bytes per channel. Applications using this
attribute to determine the buffer size requirements need to consider this.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Alexandru Ardelean 
Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Add module information

2019-12-29T15:20:08+00:00

Make sure that the industrialio-buffer-dmaengine has proper license
information so it can be build as a module and loaded without tainting the
kernel.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Alexandru Ardelean 
Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Use dma_request_chan() directly for channel request

2019-11-16T16:21:56+00:00

dma_request_slave_channel_reason() is:
	dma_request_chan(dev, name)

Signed-off-by: Peter Ujfalusi 
Reviewed-by: Vinod Koul 
Signed-off-by: Jonathan Cameron

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 149

2019-05-30T18:25:18+00:00

Based on 1 normalized pattern(s):

  licensed under the gpl 2 or later

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 82 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Reviewed-by: Kate Stewart 
Reviewed-by: Richard Fontana 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190524100845.150836982@linutronix.de
Signed-off-by: Greg Kroah-Hartman

iio: buffer-dmaengine: Add missing header buffer_impl.h

2017-06-13T19:56:05+00:00

Add buffer_impl.h as buffer.h was split into interface for using and
for internals. Without this industrialio-buffer-dmaengine.c fails
to compile.

Fixes:
commit 33dd94cb972175249258329c4aaffddcc82c2005 ("iio:buffer.h - split
into buffer.h and buffer_impl.h")

Signed-off-by: Phil Reid 
Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Use dmaengine_terminate_sync()

2016-02-09T21:05:17+00:00

The DMAengine framework gained support for synchronized transfer
termination. Use the new dmaengine_terminate_sync() function instead of
dmaengine_terminate_all(), this avoids a potential race condition when
disabling the buffer.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron

iio: Add a DMAengine framework based buffer

2015-10-25T13:55:32+00:00

Add a generic fully device independent DMA buffer implementation that uses
the DMAegnine framework to perform the DMA transfers. This can be used by
converter drivers that whish to provide a DMA buffer for converters that
are connected to a DMA core that implements the DMAengine API.

Apart from allocating the buffer using iio_dmaengine_buffer_alloc() and
freeing it using iio_dmaengine_buffer_free() no additional converter driver
specific code is required when using this DMA buffer implementation.

Signed-off-by: Lars-Peter Clausen 
Signed-off-by: Jonathan Cameron