The device tree binding already lists compatible strings for these two
SoCs. They don't have the defect as seen on the H3, and the size and
register layout is the same as the A64. Furthermore, the driver does
not include nvmem cell definitions.
Add support for these two compatible strings, re-using the config for
the A64.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Originally the SID e-fuses were thought to be in big-endian format.
Later sources show that they are in fact native or little-endian.
The most compelling evidence is the thermal sensor calibration data,
which is a set of one to three 16-bit values. In native-endian they
are in 16-bit cells with increasing offsets, whereas with big-endian
they are in the wrong order, and a gap with no data will show if there
are one or three cells.
Switch to a native endian representation for the nvmem device. For the
H3, the register read-out method was already returning data in native
endian. This only affects the other SoCs.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The sunxi_sid driver currently uses a statically allocated nvmem_config
structure that is updated at probe time. This is sub-optimal as it
limits the driver to one instance, and also takes up space even if the
device is not present.
Modify the driver to allocate the nvmem_config structure at probe time,
plugging in the desired parameters along the way.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SID cells are 32-bit aligned, and a multiple of 32 bits in length. The
only outlier is the thermal sensor calibration data, which is 16 bits
per sensor. However a whole 64 bits is allocated for this purpose, so
we could consider it conforming to the rule above.
Also, the register read-out method assumes native endian, unlike the
direct MMIO method, which assumes big endian. Thus no endian conversion
is involved.
Under these assumptions, the register read-out method can be slightly
optimized. Instead of reading one word then discarding 3 bytes, read
the whole word directly into the buffer. However, for reads under 4
bytes or trailing bytes, we still use a scratch buffer to extract the
requested bytes.
We could go one step further if .word_size was 4, but changing that
would affect the sysfs interface's behavior.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the reg_read callbacks already support arbitrary, but 4-byte
aligned. offsets and lengths into the SID, there is no need for another
for loop just to use it to read 1 byte at a time.
Read out the whole SID block in one go.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The i.MX OCOTP controller is used in numerous Freescale/NXP
SoCs from the MXC family, so the strict dependency on the
i.MX6 SoC is too narrow. Broaden it to cover all the MXC
familiy members.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The i.MX8MQ uses the same OCOTP block as the i.MX7D, but with
fourfold increase in fuse banks.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the big char/misc driver patch pull request for 5.1-rc1.
The largest thing by far is the new habanalabs driver for their AI
accelerator chip. For now it is in the drivers/misc directory but will
probably move to a new directory soon along with other drivers of this
type.
Other than that, just the usual set of individual driver updates and
fixes. There's an "odd" merge in here from the DRM tree that they asked
me to do as the MEI driver is starting to interact with the i915 driver,
and it needed some coordination. All of those patches have been
properly acked by the relevant subsystem maintainers.
All of these have been in linux-next with no reported issues, most for
quite some time.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big char/misc driver patch pull request for 5.1-rc1.
The largest thing by far is the new habanalabs driver for their AI
accelerator chip. For now it is in the drivers/misc directory but will
probably move to a new directory soon along with other drivers of this
type.
Other than that, just the usual set of individual driver updates and
fixes. There's an "odd" merge in here from the DRM tree that they
asked me to do as the MEI driver is starting to interact with the i915
driver, and it needed some coordination. All of those patches have
been properly acked by the relevant subsystem maintainers.
All of these have been in linux-next with no reported issues, most for
quite some time"
* tag 'char-misc-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (219 commits)
habanalabs: adjust Kconfig to fix build errors
habanalabs: use %px instead of %p in error print
habanalabs: use do_div for 64-bit divisions
intel_th: gth: Fix an off-by-one in output unassigning
habanalabs: fix little-endian<->cpu conversion warnings
habanalabs: use NULL to initialize array of pointers
habanalabs: fix little-endian<->cpu conversion warnings
habanalabs: soft-reset device if context-switch fails
habanalabs: print pointer using %p
habanalabs: fix memory leak with CBs with unaligned size
habanalabs: return correct error code on MMU mapping failure
habanalabs: add comments in uapi/misc/habanalabs.h
habanalabs: extend QMAN0 job timeout
habanalabs: set DMA0 completion to SOB 1007
habanalabs: fix validation of WREG32 to DMA completion
habanalabs: fix mmu cache registers init
habanalabs: disable CPU access on timeouts
habanalabs: add MMU DRAM default page mapping
habanalabs: Dissociate RAZWI info from event types
misc/habanalabs: adjust Kconfig to fix build errors
...
blocking_notifier_call_chain() returns the value returned by the last
registered callback. A positive return value doesn't indicate an error
and an nvmem device should correctly register irrespective of any
notifier callback failures. Drop the retval check.
Fixes: bee1138bea ("nvmem: add a notifier chain")
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds zynqmp nvmem firmware driver to access the
SoC revision information from the hardware register.
Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
The imx-ocotp nvmem driver supports the i.MX 7D SoC too. Allow to select
the imx-ocotp driver even if only the i.MX 7D SoC has been selected.
Fixes: 711d454779 ("nvmem: octop: Add i.MX7D support")
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Once the correct cell has been found there is no need to continue
iterating, just stop there. While at it replace the goto used to leave
the loop with simple break statements.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
__nvmem_device_get() make use of bus_find_device() to get the relevant
device and this function increase the reference count of the device
found, however this is not accounted for anywhere. Fix
__nvmem_device_get() and __nvmem_device_put() to properly release this
reference count.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In nvmem_device_get(), when the device lookup fails with DT it
currently fallback on nvmem_find() which is wrong for two reasons.
First nvmem_find() return NULL when nothing is found instead of an
ERR_PTR. But nvmem_find() also just lookup the device, it doesn't
reference the module and increment the reference count like it is done
in the DT path.
To fix this we replace the call to nvmem_find() with a call to
__nvmem_device_get() which does all the referencing and return a
proper ERR_PTR in case of error.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
of_nvmem_device_get() would crash if NULL was passed as a connection
ID. Rework this to use the usual sementic of assuming the first
connection when no connection ID is given.
Furthermore of_nvmem_device_get() would return -EINVAL when it failed
to resolve the connection, making it impossible to properly implement
an optional connection. Return -ENOENT instead to let the caller know
that the connection doesn't exists.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the cell list is not empty and nvmem_find_cell_by_node/name() is
called for a cell that is not present in the list they will return an
invalid pointer instead of NULL. This happen because
list_for_each_entry() stop once it reach the list head again, but as
the list head is not contained in a struct nvmem_cell the iteration
variable then contains an invalid value.
This is easily solved by using a variable to iterate over the list and
one to return the cell found.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
of_nvmem_cell_get() should return -ENOENT when a cell isn't defined,
otherwise callers can't distinguish between a missing cell and other
errors.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If no write callback is given the device should be marked as read-only.
While at it also move from a bit or to a logical or as that is a logical
expression.
Signed-off-by: Alban Bedel <albeu@free.fr>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In comparision to the i.MX6UL the lower cost variants i.MX6ULL/ULZ only
supports 8 OTP banks a 8 words.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i.MX7ULP is a new SoC of i.MX family which has 8 kbit eFuse OTP,
enable ocotp driver support for this SoC.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add ACPI support to bcm ocotp driver
This patch is based on Linux-4.20-rc7.
Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Spreadtrum SC27XX efuse data are organized by blocks and each block
contains 2 bytes data. Moreover the nvmem core always pass the offset
in byte to the controller, so we should change the offset in byte to
the correct block index and block offset to read the data.
Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We want to add nvmem support for MTD. TI DaVinci is the first platform
that will be using it, but only in non-DT mode. In order not to
introduce any new interface to supporting of which we would have to
commit - add a new config option that tells nvmem not to use the DT
node of the parent device.
This way we won't be creating nvmem devices corresponding with MTD
partitions defined in device tree. By default MTD will set this new
field to true.
Once a set of bindings for MTD nvmem cells is agreed upon, we'll be
able to remove this option.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since we put static variable to a header file it's copied to each module
that includes the header. But not all of them are actually using it.
Move nvmem_type_str array to its only user to make a compiler happy:
In file included from include/linux/rtc.h:18,
from drivers/rtc/rtc-proc.c:15:
include/linux/nvmem-provider.h:29:27: warning: 'nvmem_type_str'
defined but not used [-Wunused-const-variable=]
static const char * const nvmem_type_str[] = {
^~~~~~~~~~~~~~
Suggested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Suggested-by: Joe Perches <joe@perches.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Get and enable the peripheral clock required by the efuse device.
The driver has been handle to work without it so far because the
clock was left enabled by default but it won't be the case soon.
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a type attribute so userspace is able to know how the data is stored as
this can help taking the correct decision when selecting which device to
use. This will also help program display the proper warnings when burning
fuses for example.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
NVMEM DT support seems to be totally broken after
commit e888d445ac ("nvmem: resolve cells from DT at registration time")
Fix this!
Index used in of_nvmem_cell_get() to find cell is specific to
consumer, It can not be used for searching the cell in provider.
Use device_node instead of this to find the matching cell in device
tree case.
Fixes: e888d445ac ("nvmem: resolve cells from DT at registration time")
Reported-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nvmem_find_cell_by_index() is only called from inside an #ifdef,
so we get a build warning without CONFIG_OF:
drivers/nvmem/core.c:496:1: error: 'nvmem_find_cell_by_index' defined but not used [-Werror=unused-function]
Move it into the same #ifdef as the caller to avoid the warning.
Fixes: e888d445ac ("nvmem: resolve cells from DT at registration time")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove a variable that's no longer used from lpc18xx_eeprom_remove().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We check if the pointer returned by __nvmem_device_get() is not NULL
while we should actually check if it is not IS_ERR(nvmem). Fix it.
While we're at it: fix the next error path where we should assign an
error value to cell before returning.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In preparation to remove the node name pointer from struct device_node,
convert printf users to use the %pOFn format specifier.
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
[srinivas: rebased on top of next]
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now we have new api nvmem_add/del_cell_table() we do not want users to use
nvmem_add_cells() anymore. So mark it accordingly. I guess it was missed in
original cleanup patch.
This also fixes below warning:
core.c:355:5: warning: no previous prototype for 'nvmem_add_cells'
[-Wmissing-prototypes]
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The argument representing the cell name in the nvmem_cell_get() family
of functions is not consistend between function prototypes and
definitions. Name it 'id' in all those routines. This is in line with
other frameworks and can represent both the DT cell name from the
nvmem-cell-names property as well as the con_id field from cell
lookup entries.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a blocking notifier chain with four events (add and remove for
both devices and cells) so that users can get notified about the
addition of nvmem resources they're waiting for.
We'll use this instead of the at24 setup callback in the mityomapl138
board file.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a way for machine code users to associate devices with nvmem cells.
This restores the support for non-DT systems but following a different
approach. Cells must now be associated with devices using provided
routines and data structures before they can be retrieved using
nvmem_cell_get().
It's still possible to define cells statically in nvmem_config but
cells created this way still need to be associated with consumers using
lookup entries.
Note that nvmem_find() must be moved higher in the source file as we
want to call it from __nvmem_device_get() for devices that don't have
a device node.
The signature of __nvmem_device_get() is also changed as it's no longer
used to retrieve cells.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently we're creating a new cell structure everytime a DT user
calls nvmem_cell_get().
Change this behavior by resolving the cells during nvmem provider
registration and adding all cells to the provider's list. Make
of_nvmem_cell_get() just parse the phandle and look the cell up
in the relevant provider's list.
Don't drop the cell in nvmem_cell_put().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add new structs and routines allowing users to define nvmem cells from
machine code. This global list of entries is parsed when a provider
is registered and cells are associated with the relevant nvmem_device
struct.
A possible improvement for the future is to allow users to register
cell tables after the nvmem provider has been registered by updating
the cell list at each call to nvmem_(add|del)_cell_table().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nvmem subsystem keeps a global list of cells that, for non-DT systems,
can only be referenced by cell name, which makes it impossible to have
more than one nvmem device with cells named the same.
This patch makes every nvmem device the owner of the list of its cells.
This effectively removes the support for non-DT systems, but it will
be reintroduced following a different approach in subsequent patches.
This isn't a problem as support for board files in nvmem is currently
broken anyway: any user that would try to get an nvmem cell from the
global cell list would remove the cell after the calling
nvmem_cell_put(). This can cause anything from a subsequent user not
being able to get the cell to double free errors if more users hold
reference to the same cell at the same time.
Fortunately there are no such users which allows us to rework this part.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We switched the nvmem framework to using kref instead of manually
checking the current number of users in nvmem_unregister() so this
function can no longer fail. We also converted all remaining users
that still checked the return value of nvmem_unregister() to using
devm_nvmem_register(). Make the routine return void.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the managed version of nvmem_register().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver currently returns -EINVAL if kzalloc() fails in probe().
Change it to -ENOMEM as it should be.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use kref for reference counting. Use an approach similar to the one
seen in the common clock subsystem: don't actually destroy the nvmem
device until the last user puts it. This way we can get rid of the
users check from nvmem_unregister().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fabrice Gasnier