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>
This function can fail so check its return value in nvmem_register()
and act accordingly.
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>
There are two empty lines between devm_nvmem_unregister() and
__nvmem_device_get(). Remove one.
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 provided helper for iterating over list entries without having
to use the list_entry() macro.
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>
This field is never set and is only used in a single error message.
Remove the field and use nvmem_dev_name() instead.
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>
Kernel users don't have any means of checking the names of nvmem
devices. Add a routine that returns the name of the nvmem provider.
This will be useful for future nvmem notifier subscribers - otherwise
they can't check what device is being added/removed.
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_device_get() should return ERR_PTR() on error or valid pointer
on success, but one of the code path seems to return NULL, so fix it.
Reported-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i.MX6SLL is a new SoC of i.MX6 family, 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>
This patch add the efuse driver which is embeded in Spreadtrum SC27XX
series PMICs. The sc27xx efuse contains 32 blocks and each block's
data width is 16 bits.
Signed-off-by: Freeman Liu <freeman.liu@spreadtrum.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>
At over 4000 #includes, <linux/platform_device.h> is the 9th most
#included header file in the Linux kernel. It does not need
<linux/mod_devicetable.h>, so drop that header and explicitly add
<linux/mod_devicetable.h> to source files that need it.
4146 #include <linux/platform_device.h>
After this patch, there are 225 files that use <linux/mod_devicetable.h>,
for a reduction of around 3900 times that <linux/mod_devicetable.h>
does not have to be read & parsed.
225 #include <linux/mod_devicetable.h>
This patch was build-tested on 20 different arch-es.
It also makes these drivers SubmitChecklist#1 compliant.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kbuild test robot <lkp@intel.com> # drivers/media/platform/vimc/
Reported-by: kbuild test robot <lkp@intel.com> # drivers/pinctrl/pinctrl-u300.c
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nvmem ncells can be over written by calling nvmem_add_cells()
multiple times. I see there is no real point of maintaining count
of cells when we have a list of cell.
Remove this to avoid any confusion!
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the quest to remove all stack VLA usage from the kernel[1], this
uses the maximum allocation size for the stack and adds a sanity check,
similar to what has already be done for the regular rave-sp driver.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Tested-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit ca04d9d3e1 ("phy: qcom-qusb2: New driver for QUSB2 PHY on
Qcom chips") you can see a call like:
devm_nvmem_cell_get(dev, NULL);
Note that the cell ID passed to the function is NULL. This is because
the qcom-qusb2 driver is expected to work only on systems where the
PHY node is hooked up via device-tree and is nameless.
This works OK for the most part. The first thing nvmem_cell_get()
does is to call of_nvmem_cell_get() and there it's documented that a
NULL name is fine. The problem happens when the call to
of_nvmem_cell_get() returns -EINVAL. In such a case we'll fall back
to nvmem_cell_get_from_list() and eventually might (if nvmem_cells
isn't an empty list) crash with something that looks like:
strcmp
nvmem_find_cell
__nvmem_device_get
nvmem_cell_get_from_list
nvmem_cell_get
devm_nvmem_cell_get
qusb2_phy_probe
There are several different ways we could fix this problem:
One could argue that perhaps the qcom-qusb2 driver should be changed
to use of_nvmem_cell_get() which is allowed to have a NULL name. In
that case, we'd need to add a patche to introduce
devm_of_nvmem_cell_get() since the qcom-qusb2 driver is using devm
managed resources.
One could also argue that perhaps we could just add a name to
qcom-qusb2. That would be OK but I believe it effectively changes the
device tree bindings, so maybe it's a no-go.
In this patch I have chosen to fix the problem by simply not crashing
when a NULL cell_id is passed to nvmem_cell_get().
NOTE: that for the qcom-qusb2 driver the "nvmem-cells" property is
defined to be optional and thus it's expected to be a common case that
we would hit this crash and this is more than just a theoretical fix.
Fixes: ca04d9d3e1 ("phy: qcom-qusb2: New driver for QUSB2 PHY on Qcom chips")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Function nvmem_reg_read can return a non zero value indicating an error.
This returned value must be read and error propagated to
nvmem_cell_prepare_write_buffer. Silence the following gcc warning (W=1):
drivers/nvmem/core.c:1093:9: warning: variable 'rc' set but
not used [-Wunused-but-set-variable]
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Document dev parameter which not described in devm_nvmem_unregister
and devm_nvmem_register functions.
Fix below warnings when kernel is compiled with W=1
drivers/nvmem/core.c:579: warning: Function parameter or member
'dev' not described in 'devm_nvmem_register'
nvmem/core.c:615: warning: Function parameter or member 'dev'
not described in 'devm_nvmem_unregister'
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add write support to the meson-gx efuse driver.
Beware, this efuse is one time programmable !
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
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>
Most of the code and variables in the read callback is not necessary.
Keep only what is required.
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>
Having a global structure holding a reference to the device
structure is not very nice. Allocate the econfig instead and fill
the nvmem information as before
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
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>
Not all platforms use device tree. It is useful to be able to add
cells to a NVMEM device from code. Export nvmem_add_cells() so making
this possible.
This required changing the parameters a bit, so that just the cells
and the number of cells are passed, not the whole nvmem config
structure.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the big set of char/misc driver patches for 4.17-rc1.
There are a lot of little things in here, nothing huge, but all
important to the different hardware types involved:
- thunderbolt driver updates
- parport updates (people still care...)
- nvmem driver updates
- mei updates (as always)
- hwtracing driver updates
- hyperv driver updates
- extcon driver updates
- and a handfull of even smaller driver subsystem and individual
driver updates
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWsShSQ8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ykNqwCfUbfvopswb1PesHCLABDBsFQChgoAniDa6pS9
kI8TN5MdLN85UU27Mkb6
=BzFR
-----END PGP SIGNATURE-----
Merge tag 'char-misc-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc updates from Greg KH:
"Here is the big set of char/misc driver patches for 4.17-rc1.
There are a lot of little things in here, nothing huge, but all
important to the different hardware types involved:
- thunderbolt driver updates
- parport updates (people still care...)
- nvmem driver updates
- mei updates (as always)
- hwtracing driver updates
- hyperv driver updates
- extcon driver updates
- ... and a handful of even smaller driver subsystem and individual
driver updates
All of these have been in linux-next with no reported issues"
* tag 'char-misc-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (149 commits)
hwtracing: Add HW tracing support menu
intel_th: Add ACPI glue layer
intel_th: Allow forcing host mode through drvdata
intel_th: Pick up irq number from resources
intel_th: Don't touch switch routing in host mode
intel_th: Use correct method of finding hub
intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate
stm class: Make dummy's master/channel ranges configurable
stm class: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate
MAINTAINERS: Bestow upon myself the care for drivers/hwtracing
hv: add SPDX license id to Kconfig
hv: add SPDX license to trace
Drivers: hv: vmbus: do not mark HV_PCIE as perf_device
Drivers: hv: vmbus: respect what we get from hv_get_synint_state()
/dev/mem: Avoid overwriting "err" in read_mem()
eeprom: at24: use SPDX identifier instead of GPL boiler-plate
eeprom: at24: simplify the i2c functionality checking
eeprom: at24: fix a line break
eeprom: at24: tweak newlines
eeprom: at24: refactor at24_probe()
...
The new of_get_nvmem_mac_address() helper function causes a link error
with CONFIG_NVMEM=m:
drivers/of/of_net.o: In function `of_get_nvmem_mac_address':
of_net.c:(.text+0x168): undefined reference to `of_nvmem_cell_get'
of_net.c:(.text+0x19c): undefined reference to `nvmem_cell_read'
of_net.c:(.text+0x1a8): undefined reference to `nvmem_cell_put'
I could not come up with a good solution for this, as the code is always
built-in. Using an #if IS_REACHABLE() check around it would solve the
link time issue but then stop it from working in that configuration.
Making of_nvmem_cell_get() an inline function could also solve that, but
seems a bit ugly since it's somewhat larger than most inline functions,
and it would just bring that problem into the callers. Splitting the
function into a separate file might be an alternative.
This uses the big hammer by making CONFIG_NVMEM itself a 'bool' symbol,
which avoids the problem entirely but makes the vmlinux larger for anyone
that might use NVMEM support but doesn't need it built-in otherwise.
Fixes: 9217e566bd ("of_net: Implement of_get_nvmem_mac_address helper")
Cc: Mike Looijmans <mike.looijmans@topic.nl>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mike Looijmans
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems that doing some operation will make the value pre-read on H3
SID controller wrong again, so all operation should be performed by
register.
Change the SID reading to use register only.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The i.MX7 family has similar SNVS hardware so make the snvs-lpgpr
support it along with the i.MX6 family. The register interface is the
same except for the number and offset of the general purpose registers.
Signed-off-by: Andrey Yurovsky <yurovsky@gmail.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
