When userspace needs to find a specific device, it currently isn't easy to
resolve a /sys/devices/ path from a specific device tree node. Nor is it
easy to obtain the compatible list for devices.
This patch generalizes the code that inserts OF_* values into the uevent
device attribute so that any device that is attached to an OF node will
have that information exported to userspace. Without this patch only
platform devices and some powerpc-specific busses have access to this
data.
The original function also creates a MODALIAS property for the compatible
list, but that code has not been generalized into the common case because
it has the potential to break module loading on a lot of bus types. Bus
types are still responsible for their own MODALIAS properties.
Boot tested on ARM and compile tested on PowerPC and SPARC.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Frederic Lambert <frdrc66@gmail.com>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Mark Brown <broonie@sirena.org.uk>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
PM / Hibernate: Implement compat_ioctl for /dev/snapshot
PM / Freezer: fix return value of freezable_schedule_timeout_killable()
PM / shmobile: Allow the A4R domain to be turned off at run time
PM / input / touchscreen: Make st1232 use device PM QoS constraints
PM / QoS: Introduce dev_pm_qos_add_ancestor_request()
PM / shmobile: Remove the stay_on flag from SH7372's PM domains
PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume
PM / shmobile: Add support for the sh7372 A4S power domain / sleep mode
PM: Drop generic_subsys_pm_ops
PM / Sleep: Remove forward-only callbacks from AMBA bus type
PM / Sleep: Remove forward-only callbacks from platform bus type
PM: Run the driver callback directly if the subsystem one is not there
PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
PM/Devfreq: Add Exynos4-bus device DVFS driver for Exynos4210/4212/4412.
PM / Sleep: Merge internal functions in generic_ops.c
PM / Sleep: Simplify generic system suspend callbacks
PM / Hibernate: Remove deprecated hibernation snapshot ioctls
PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
ARM: S3C64XX: Implement basic power domain support
PM / shmobile: Use common always on power domain governor
...
Fix up trivial conflict in fs/xfs/xfs_buf.c due to removal of unused
XBT_FORCE_SLEEP bit
The forward-only PM callbacks provided by the platform bus type are
not necessary any more, because the PM core executes driver callbacks
when the corresponding subsystem callbacks are not present, so drop
them.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
platform_device_register_full doesn't modify *pdevinfo so it can be
marked as const without further adaptions.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits)
mm: memory hotplug: Check if pages are correctly reserved on a per-section basis
Revert "memory hotplug: Correct page reservation checking"
Update email address for stable patch submission
dynamic_debug: fix undefined reference to `__netdev_printk'
dynamic_debug: use a single printk() to emit messages
dynamic_debug: remove num_enabled accounting
dynamic_debug: consolidate repetitive struct _ddebug descriptor definitions
uio: Support physical addresses >32 bits on 32-bit systems
sysfs: add unsigned long cast to prevent compile warning
drivers: base: print rejected matches with DEBUG_DRIVER
memory hotplug: Correct page reservation checking
memory hotplug: Refuse to add unaligned memory regions
remove the messy code file Documentation/zh_CN/SubmitChecklist
ARM: mxc: convert device creation to use platform_device_register_full
new helper to create platform devices with dma mask
docs/driver-model: Update device class docs
docs/driver-model: Document device.groups
kobj_uevent: Ignore if some listeners cannot handle message
dynamic_debug: make netif_dbg() call __netdev_printk()
dynamic_debug: make netdev_dbg() call __netdev_printk()
...
compared to the most powerful and already existing helper (namely
platform_device_register_resndata) this allows to specify a dma_mask.
To make eventual extensions later more easy, a struct holding the used
information is created instead of passing the information by function
parameters.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If id_entry is available then it is used. However if we remove first the
driver followed by the device, then the id_entry is pointing to driver's
memory which is long gone.
Since id->name and plat->name are equal there is no point in
distinguishing them.
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Warning(drivers/base/platform.c:50): No description found for parameter 'pdev'
Warning(drivers/base/platform.c:50): Excess function parameter 'dev' description in 'arch_setup_pdev_archdata'
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some architectures we need to setup pdev_archdata before we add the
device. Waiting til a bus_notifier is too late since we might need the
pdev_archdata in the bus notifier. One example is setting up of dma_mask
pointers such that it can be used in a bus_notifier.
We add weak noop version of arch_setup_pdev_archdata() and allow the arch
code to override with access the full definitions of struct device,
struct platform_device, and struct pdev_archdata.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This reverts 737a3bb941 ("Driver core: move platform device
creation helpers to .init.text (if MODULE=n)"). That patch assumed that
platform_device_register_resndata() is only ever called from __init code
but that isn't true in the case ioctl->drm_ioctl->radeon_cp_init().
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=35192
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reported-by: Anthony Basile <blueness@gentoo.org>
Cc: Greg KH <gregkh@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (44 commits)
debugfs: Silence DEBUG_STRICT_USER_COPY_CHECKS=y warning
sysfs: remove "last sysfs file:" line from the oops messages
drivers/base/memory.c: fix warning due to "memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION"
memory hotplug: Speed up add/remove when blocks are larger than PAGES_PER_SECTION
SYSFS: Fix erroneous comments for sysfs_update_group().
driver core: remove the driver-model structures from the documentation
driver core: Add the device driver-model structures to kerneldoc
Translated Documentation/email-clients.txt
RAW driver: Remove call to kobject_put().
reboot: disable usermodehelper to prevent fs access
efivars: prevent oops on unload when efi is not enabled
Allow setting of number of raw devices as a module parameter
Introduce CONFIG_GOOGLE_FIRMWARE
driver: Google Memory Console
driver: Google EFI SMI
x86: Better comments for get_bios_ebda()
x86: get_bios_ebda_length()
misc: fix ti-st build issues
params.c: Use new strtobool function to process boolean inputs
debugfs: move to new strtobool
...
Fix up trivial conflicts in fs/debugfs/file.c due to the same patch
being applied twice, and an unrelated cleanup nearby.
The platform_bus_set_pm_ops() operation is deprecated in favor of the
new device power domain infrastructre implemented in commit
7538e3db6e (PM: add support for device
power domains)
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Once shmobile platforms have been converted to using power domains
for overriding the platform bus type's PM callbacks, it isn't
necessary to use the __weakly defined wrappers around the generinc
runtime PM callbacks in the platform bus type any more.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Export the default PM callbacks defined for the platform bus type so
that they can be used by power domains for suspending and resuming
platform devices in the future.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This makes the res = NULL case more consistant to the res != NULL case
as now both overwrite pdev->resource.
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes the data = NULL case more consistent to the data != NULL case.
The functional change is that now
platform_device_add_data(somepdev, NULL, somesize)
sets pdev->dev.platform_data to NULL instead of not touching it.
Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In order for MFD drivers to fetch their cell pointer but also their
platform data one, an mfd cell pointer is added to the platform_device
structure.
That allows all MFD sub devices drivers to be MFD agnostic, unless
they really need to access their MFD cell data. Most of them don't,
especially the ones for IPs used by both MFD and non MFD SoCs.
Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg KH <gregkh@suse.de>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose. However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation. Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.
To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6:
mtd/m25p80: add support to parse the partitions by OF node
of/irq: of_irq.c needs to include linux/irq.h
of/mips: Cleanup some include directives/files.
of/mips: Add device tree support to MIPS
of/flattree: Eliminate need to provide early_init_dt_scan_chosen_arch
of/device: Rework to use common platform_device_alloc() for allocating devices
of/xsysace: Fix OF probing on little-endian systems
of: use __be32 types for big-endian device tree data
of/irq: remove references to NO_IRQ in drivers/of/platform.c
of/promtree: add package-to-path support to pdt
of/promtree: add of_pdt namespace to pdt code
of/promtree: no longer call prom_ functions directly; use an ops structure
of/promtree: make drivers/of/pdt.c no longer sparc-only
sparc: break out some PROM device-tree building code out into drivers/of
of/sparc: convert various prom_* functions to use phandle
sparc: stop exporting openprom.h header
powerpc, of_serial: Endianness issues setting up the serial ports
of: MTD: Fix OF probing on little-endian systems
of: GPIO: Fix OF probing on little-endian systems
There's no need to explicitly check for data and resources being NULL,
as platform_device_add_{data,resources}() do this internally nowadays.
This makes the code more linear and less indented.
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some users of platform_device_add_{data,resources}() assume that
NULL data and resources will be handled specially, i.e. just ignored.
But the platform core ends up calling kmemdup(NULL, 0, ...), which
returns a non-NULL result (i.e. ZERO_SIZE_PTR), which causes drivers
to oops on a valid code, something like:
if (platform_data)
stuff = platform_data->stuff;
This patch makes the platform core a bit more safe for such cases.
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently, the platform_bus allows customization of several of the
busses dev_pm_ops methods by using weak symbols so that platform code
can override them. The weak-symbol approach is not scalable when
wanting to support multiple platforms in a single kernel binary.
Instead, provide __init methods for platform code to customize the
dev_pm_ops methods at runtime.
NOTE: after these dynamic methods are merged, the weak symbols should
be removed from drivers/base/platform.c. AFAIK, this will only
affect SH and sh-mobile which should be converted to use this
runtime approach instead of the weak symbols. After SH &
sh-mobile are converted, the weak symobols could be removed.
Tested on OMAP3.
Cc: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In theory (although not *yet* in practice), a driver being passed
to platform_driver_probe might have driver.bus set to something
other than platform_bus_type. Locking drv->driver.bus is always
correct.
Signed-off-by: Patrick Pannuto <ppannuto@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current code allocates and manages platform_devices created from
the device tree manually. It also uses an unsafe shortcut for
allocating the platform_device and the resource table at the same
time. (which I added in the last rework; sorry).
This patch refactors the code to use platform_device_alloc() for
allocating new devices. This reduces the amount of custom code
implemented by of_platform, eliminates the unsafe alloc trick, and has
the side benefit of letting the platform_bus code manage freeing the
device data and resources when the device is freed.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michal Simek <monstr@monstr.eu>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (28 commits)
driver core: device_rename's new_name can be const
sysfs: Remove owner field from sysfs struct attribute
powerpc/pci: Remove owner field from attribute initialization in PCI bridge init
regulator: Remove owner field from attribute initialization in regulator core driver
leds: Remove owner field from attribute initialization in bd2802 driver
scsi: Remove owner field from attribute initialization in ARCMSR driver
scsi: Remove owner field from attribute initialization in LPFC driver
cgroupfs: create /sys/fs/cgroup to mount cgroupfs on
Driver core: Add BUS_NOTIFY_BIND_DRIVER
driver core: fix memory leak on one error path in bus_register()
debugfs: no longer needs to depend on SYSFS
sysfs: Fix one more signature discrepancy between sysfs implementation and docs.
sysfs: fix discrepancies between implementation and documentation
dcdbas: remove a redundant smi_data_buf_free in dcdbas_exit
dmi-id: fix a memory leak in dmi_id_init error path
sysfs: sysfs_chmod_file's attr can be const
firmware: Update hotplug script
Driver core: move platform device creation helpers to .init.text (if MODULE=n)
Driver core: reduce duplicated code for platform_device creation
Driver core: use kmemdup in platform_device_add_resources
...
Platform devices should only be called by init code, so it should be
possible to move creation helpers to .init.text -- at least if modules
are disabled.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes the two similar functions platform_device_register_simple
and platform_device_register_data one line inline functions using a new
generic function platform_device_register_resndata.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This makes platform_device_add_resources look like
platform_device_add_data.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
of_platform_bus was being used in the same manner as the platform_bus.
The only difference being that of_platform_bus devices are generated
from data in the device tree, and platform_bus devices are usually
statically allocated in platform code. Having them separate causes
the problem of device drivers having to be registered twice if it
was possible for the same device to appear on either bus.
This patch removes of_platform_bus_type and registers all of_platform
bus devices and drivers on the platform bus instead. A previous patch
made the of_device structure an alias for the platform_device structure,
and a shim is used to adapt of_platform_drivers to the platform bus.
After all of of_platform_bus drivers are converted to be normal platform
drivers, the shim code can be removed.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
As part of the merge between platform bus and of_platform bus, add the
ability to do of-style matching to the platform bus.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
CC: Michal Simek <monstr@monstr.eu>
CC: Grant Likely <grant.likely@secretlab.ca>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: linux-kernel@vger.kernel.org
CC: microblaze-uclinux@itee.uq.edu.au
CC: linuxppc-dev@ozlabs.org
CC: devicetree-discuss@lists.ozlabs.org
When runtime PM for platform_bus was added, it allowed for platforms
to customize the runtime PM methods since they are defined as weak
symbols.
This patch allows platforms to also extend the system PM methods with
custom hooks so runtime PM and system PM extensions can be managed
together by custom platform-specific code.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Rafael Wysocki <rjw@sisk.pl>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (127 commits)
sh: update defconfigs.
sh: Fix up the NUMA build for recent LMB changes.
sh64: provide a stub per_cpu_trap_init() definition.
sh: fix up CONFIG_KEXEC=n build.
sh: fixup the docbook paths for clock framework shuffling.
driver core: Early dev_name() depends on slab_is_available().
sh: simplify WARN usage in SH clock driver
sh: Check return value of clk_get on ms7724
sh: Check return value of clk_get on ecovec24
sh: move sh clock-cpg.c contents to drivers/sh/clk-cpg.c
sh: move sh clock.c contents to drivers/sh/clk.
sh: move sh asm/clock.h contents to linux/sh_clk.h V2
sh: remove unused clock lookup
sh: switch boards to clkdev
sh: switch sh4-202 to clkdev
sh: switch shx3 to clkdev
sh: switch sh7757 to clkdev
sh: switch sh7763 to clkdev
sh: switch sh7780 to clkdev
sh: switch sh7786 to clkdev
...
Make the platform resource input parameters of platform_device_add_resources()
and platform_device_register_simple() const, as the resources are copied and
never modified.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
The early dev_name() setup needs to do an allocation which can only be
satisfied under slab_is_available() conditions. Some of the early
platform drivers may be initialized before this point, and those still
need to contend themselves with an empty dev_name.
This fixes up a regression with the SH earlyprintk which was bailing out
prior to hitting the early probe path due to not being able to satisfy
the early allocation. Other early platform drivers (such as the early
timers) that need to match the dev name are sufficiently late that
allocations are already possible.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Currently the default runtime PM callbacks for platform devices return
-ENOSYS, preventing the use of runtime PM platforms until they have
provided at least a default implementation. This hinders the use of
runtime PM by devices which work with many platforms such as memory
mapped devices, MFDs and on chip IPs shared by multiple architectures.
Change the default implementation to the standard pm_generic_runtime
one, allowing drivers to use runtime PM without per-architecture
changes.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This is just a simple refactoring patch on top of the early dev_name()
support, converting from kstrdup() to kasprintf() as suggested by Kay.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
A number of functions in the driver core return ERR_PTR() values on
error. Document this in the kernel-doc of the functions.
Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch updates the kernel-doc notation for early
platform functions.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Presently early platform devices suffer from the fact they are unable to
use dev_xxx() calls early on due to dev_name() and others being
unavailable at the time ->probe() is called.
This implements early init_name construction from the matched name/id
pair following the semantics of the late device/driver match. As a
result, matched IDs (inclusive of requested ones) are preserved when the
handoff from the early platform code happens at kobject initialization
time.
Since we still require kmalloc slabs to be available at this point, using
kstrdup() for establishing the init_name works fine. This subsequently
needs to be tested from dev_name() prior to the init_name being cleared
by the driver core. We don't kfree() since others will already have a
handle on the string long before the kobject initialization takes place.
This is also needed to permit drivers to use the clock framework early,
without having to manually construct their own device IDs from the match
id/name pair locally (needed by the early console and timer code on sh
and arm).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
The function name must be followed by a space, hypen, space, and a
short description.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes a warning on several pxa based machines:
arch/arm/mach-pxa/ssp.c:475: warning: initialization discards qualifiers from pointer target type
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Vikram Dhillon <dhillonv10@gmail.com>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Many legacy-style module create singleton platform devices themselves,
along with corresponding platform driver. Instead of replicating error
handling code in all such drivers, provide a helper that allocates and
registers a single platform device and a driver and binds them together.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This allows MFD's to register/bind drivers for their sub devices while
still being compiled as a module.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add early_platform_init_buffer() support and update the
early platform driver code to allow passing parameters
to the driver on the kernel command line.
early_platform_init_buffer() simply allows early platform
drivers to provide a pointer and length to a memory area
where the remaining part of the kernel command line option
will be stored.
Needed to pass baud rate and other serial port options
to the reworked early serial console code on SuperH.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>