linux-toradex.git/drivers/base/Kconfig, branch tegra

drivers/base: add bus for System-on-Chip devices

2017-03-31T08:24:52+00:00

Traditionally, any System-on-Chip based platform creates a flat list
of platform_devices directly under /sys/devices/platform.

In order to give these some better structure, this introduces a new
bus type for soc_devices that are registered with the new
soc_device_register() function.  All devices that are on the same
chip should then be registered as child devices of the soc device.

The soc bus also exports a few standardised device attributes which
allow user space to query the specific type of soc.

Signed-off-by: Lee Jones 
Signed-off-by: Greg Kroah-Hartman 
(cherry picked from commit 74d1d82cdaaec727f5072eb1c9f49b7e920e076f)

dma-buf: Introduce dma buffer sharing mechanism

2012-02-03T13:20:29+00:00

This is the first step in defining a dma buffer sharing mechanism.

A new buffer object dma_buf is added, with operations and API to allow easy
sharing of this buffer object across devices.

The framework allows:
- creation of a buffer object, its association with a file pointer, and
   associated allocator-defined operations on that buffer. This operation is
   called the 'export' operation.
- different devices to 'attach' themselves to this exported buffer object, to
  facilitate backing storage negotiation, using dma_buf_attach() API.
- the exported buffer object to be shared with the other entity by asking for
   its 'file-descriptor (fd)', and sharing the fd across.
- a received fd to get the buffer object back, where it can be accessed using
   the associated exporter-defined operations.
- the exporter and user to share the scatterlist associated with this buffer
   object using map_dma_buf and unmap_dma_buf operations.

Atleast one 'attach()' call is required to be made prior to calling the
map_dma_buf() operation.

Couple of building blocks in map_dma_buf() are added to ease introduction
of sync'ing across exporter and users, and late allocation by the exporter.

For this first version, this framework will work with certain conditions:
- *ONLY* exporter will be allowed to mmap to userspace (outside of this
   framework - mmap is not a buffer object operation),
- currently, *ONLY* users that do not need CPU access to the buffer are
   allowed.

More details are there in the documentation patch.

This is based on design suggestions from many people at the mini-summits[1],
most notably from Arnd Bergmann , Rob Clark  and
Daniel Vetter .

The implementation is inspired from proof-of-concept patch-set from
Tomasz Stanislawski , who demonstrated buffer sharing
between two v4l2 devices. [2]

[1]: https://wiki.linaro.org/OfficeofCTO/MemoryManagement
[2]: http://lwn.net/Articles/454389

Change-Id: I8ebd858ad86242ee7b02d5f42bb25c3edbd64fca
Signed-off-by: Sumit Semwal 
Signed-off-by: Sumit Semwal 
Reviewed-by: Daniel Vetter 
Reviewed-by: Dave Airlie 
Reviewed-and-Tested-by: Rob Clark 
Signed-off-by: Dave Airlie 
Signed-off-by: Hiroshi DOYU 
[Hiroshi DOYU: Backported from v3.3-rc1]
Reviewed-on: http://git-master/r/78384
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Varun Wadekar 
Reviewed-by: Ken Adams

Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6

2011-07-26T06:06:24+00:00

* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
  updated Documentation/ja_JP/SubmittingPatches
  debugfs: add documentation for debugfs_create_x64
  uio: uio_pdrv_genirq: Add OF support
  firmware: gsmi: remove sysfs entries when unload the module
  Documentation/zh_CN: Fix messy code file email-clients.txt
  driver core: add more help description for "path to uevent helper"
  driver-core: modify FIRMWARE_IN_KERNEL help message
  driver-core: Kconfig grammar corrections in firmware configuration
  DOCUMENTATION: Replace create_device() with device_create().
  DOCUMENTATION: Update overview.txt in Doc/driver-model.
  pti: pti_tty_install documentation mispelling.

regmap: Add generic non-memory mapped register access API

2011-07-23T06:56:03+00:00

There are many places in the tree where we implement register access for
devices on non-memory mapped buses, especially I2C and SPI. Since hardware
designers seem to have settled on a relatively consistent set of register
interfaces this can be effectively factored out into shared code.  There
are a standard set of formats for marshalling data for exchange with the
device, with the actual I/O mechanisms generally being simple byte
streams.

We create an abstraction for marshaling data into formats which can be
sent on the control interfaces, and create a standard method for
plugging in actual transport underneath that.

This is mostly a refactoring and renaming of the bottom level of the
existing code for sharing register I/O which we have in ASoC. A
subsequent patch in this series converts ASoC to use this.  The main
difference in interface is that reads return values by writing to a
location provided by a pointer rather than in the return value, ensuring
we can use the full range of the type for register data.  We also use
unsigned types rather than ints for the same reason.

As some of the devices can have very large register maps the existing
ASoC code also contains infrastructure for managing register caches.
This cache work will be moved over in a future stage to allow for
separate review, the current patch only deals with the physical I/O.

Signed-off-by: Mark Brown 
Acked-by: Liam Girdwood 
Acked-by: Greg Kroah-Hartman 
Acked-by: Wolfram Sang 
Acked-by: Grant Likely

driver core: add more help description for "path to uevent helper"

2011-07-01T22:12:15+00:00

The kernel configuration UEVENT_HELPER_PATH is a string to
the uevent helper program. Add more description about how
to disable this feature and how to enable it again during
runtime.

Signed-off-by: Márton Németh 
Signed-off-by: Greg Kroah-Hartman

driver-core: modify FIRMWARE_IN_KERNEL help message

2011-07-01T22:12:03+00:00

The help message for the configuration variable was inconsistent
with the way "make firmware_install" really works.

Signed-off-by: matt mooney 
Signed-off-by: Greg Kroah-Hartman

driver-core: Kconfig grammar corrections in firmware configuration

2011-07-01T22:12:02+00:00

Fix some grammatical errors and reword a few sentences.

Signed-off-by: matt mooney 
Signed-off-by: Greg Kroah-Hartman

PM: Remove sysdev suspend, resume and shutdown operations

2011-05-11T19:37:15+00:00

Since suspend, resume and shutdown operations in struct sysdev_class
and struct sysdev_driver are not used any more, remove them.  Also
drop sysdev_suspend(), sysdev_resume() and sysdev_shutdown() used
for executing those operations and modify all of their users
accordingly.  This reduces kernel code size quite a bit and reduces
its complexity.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Greg Kroah-Hartman

Introduce ARCH_NO_SYSDEV_OPS config option (v2)

2011-03-23T21:16:41+00:00

Introduce Kconfig option allowing architectures where sysdev
operations used during system suspend, resume and shutdown have been
completely replaced with struct sycore_ops operations to avoid
building sysdev code that will never be used.

Make callbacks in struct sys_device and struct sysdev_driver depend
on ARCH_NO_SYSDEV_OPS to allows us to verify if all of the references
have been actually removed from the code the given architecture
depends on.

Make x86 select ARCH_NO_SYSDEV_OPS.

Signed-off-by: Rafael J. Wysocki

kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

2011-01-21T01:02:05+00:00

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.

Reviewed-by: Ingo Molnar 
Acked-by: David Woodhouse 
Signed-off-by: David Rientjes 
Cc: Greg KH 
Cc: "David S. Miller" 
Cc: Jens Axboe 
Cc: Arnd Bergmann 
Cc: Robin Holt 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds