Commit Graph

23 Commits

Author SHA1 Message Date
Srinivas Kandagatla 5008062f1c nvmem: core: add nvmem cell post processing callback
Some NVMEM providers have certain nvmem cells encoded, which requires
post processing before actually using it.

For example mac-address is stored in either in ascii or delimited or reverse-order.

Having a post-process callback hook to provider drivers would enable them to
do this vendor specific post processing before nvmem consumers see it.

Tested-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20211013131957.30271-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-13 15:33:17 +02:00
Linus Torvalds eed0218e8c Char / Misc driver updates for 5.14-rc1
Here is the big set of char / misc and other driver subsystem updates
 for 5.14-rc1.  Included in here are:
 	- habanna driver updates
 	- fsl-mc driver updates
 	- comedi driver updates
 	- fpga driver updates
 	- extcon driver updates
 	- interconnect driver updates
 	- mei driver updates
 	- nvmem driver updates
 	- phy driver updates
 	- pnp driver updates
 	- soundwire driver updates
 	- lots of other tiny driver updates for char and misc drivers
 
 This is looking more and more like the "various driver subsystems mushed
 together" tree...
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.14-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 set of char / misc and other driver subsystem updates
  for 5.14-rc1. Included in here are:

   - habanalabs driver updates

   - fsl-mc driver updates

   - comedi driver updates

   - fpga driver updates

   - extcon driver updates

   - interconnect driver updates

   - mei driver updates

   - nvmem driver updates

   - phy driver updates

   - pnp driver updates

   - soundwire driver updates

   - lots of other tiny driver updates for char and misc drivers

  This is looking more and more like the "various driver subsystems
  mushed together" tree...

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits)
  mcb: Use DEFINE_RES_MEM() helper macro and fix the end address
  PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable
  bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls
  bus: mhi: Wait for M2 state during system resume
  bus: mhi: core: Fix power down latency
  intel_th: Wait until port is in reset before programming it
  intel_th: msu: Make contiguous buffers uncached
  intel_th: Remove an unused exit point from intel_th_remove()
  stm class: Spelling fix
  nitro_enclaves: Set Bus Master for the NE PCI device
  misc: ibmasm: Modify matricies to matrices
  misc: vmw_vmci: return the correct errno code
  siox: Simplify error handling via dev_err_probe()
  fpga: machxo2-spi: Address warning about unused variable
  lkdtm/heap: Add init_on_alloc tests
  selftests/lkdtm: Enable various testable CONFIGs
  lkdtm: Add CONFIG hints in errors where possible
  lkdtm: Enable DOUBLE_FAULT on all architectures
  lkdtm/heap: Add vmalloc linear overflow test
  lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE
  ...
2021-07-05 13:42:16 -07:00
Jiri Prchal fd307a4ad3 nvmem: prepare basics for FRAM support
Added enum and string for FRAM (ferroelectric RAM) to expose it as file
named "fram".
Added documentation of sysfs file.

Signed-off-by: Jiri Prchal <jiri.prchal@aksignal.cz>
Link: https://lore.kernel.org/r/20210611094601.95131-2-jiri.prchal@aksignal.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-11 12:23:10 +02:00
Michael Walle 1333a67795 nvmem: core: allow specifying of_node
Until now, the of_node of the parent device is used. Some devices
provide more than just the nvmem provider. To avoid name space clashes,
add a way to allow specifying the nvmem cells in subnodes. Consider the
following example:

    flash@0 {
        compatible = "jedec,spi-nor";

        partitions {
            compatible = "fixed-partitions";
            #address-cells = <1>;
            #size-cells = <1>;

            partition@0 {
                reg = <0x000000 0x010000>;
            };
        };

        otp {
            compatible = "user-otp";
            #address-cells = <1>;
            #size-cells = <1>;

            serial-number@0 {
                reg = <0x0 0x8>;
            };
        };
    };

There the nvmem provider might be the MTD partition or the OTP region of
the flash.

Add a new config->of_node parameter, which if set, will be used instead
of the parent's of_node.

Signed-off-by: Michael Walle <michael@walle.cc>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210424110608.15748-2-michael@walle.cc
2021-05-10 12:42:46 +02:00
Evan Green fd3bb8f54a nvmem: core: Add support for keepout regions
Introduce support into the nvmem core for arrays of register ranges
that should not result in actual device access. For these regions a
constant byte (repeated) is returned instead on read, and writes are
quietly ignored and returned as successful.

This is useful for instance if certain efuse regions are protected
from access by Linux because they contain secret info to another part
of the system (like an integrated modem).

Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20201127102837.19366-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-27 16:10:06 +01:00
Srinivas Kandagatla 731aa3fae8 nvmem: core: add support to auto devid
For nvmem providers which have multiple instances, it is required
to suffix the provider name with proper id, so that they do not
confict for the same name. Currently the core does not handle
this case properly eventhough core already has logic to generate the id.

This patch add new devid type NVMEM_DEVID_AUTO for providers to be
able to allow core to assign id and append it to provier name.

Reported-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 17:12:08 +02:00
Khouloud Touil 2a127da461 nvmem: add support for the write-protect pin
The write-protect pin handling looks like a standard property that
could benefit other users if available in the core nvmem framework.

Instead of modifying all the memory drivers to check this pin, make
the NVMEM subsystem check if the write-protect GPIO being passed
through the nvmem_config or defined in the device tree and pull it
low whenever writing to the memory.

There was a suggestion for introducing the gpiodesc from pdata, but
as pdata is already removed it could be replaced by adding it to
nvmem_config.

Reference: https://lists.96boards.org/pipermail/dev/2018-August/001056.html

Signed-off-by: Khouloud Touil <ktouil@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2020-01-09 10:48:54 +01:00
Bartosz Golaszewski 517f14d9cf nvmem: add new config option
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>
2018-12-06 15:45:46 +01:00
Andy Shevchenko a8b44d5d2e nvmem: Move nvmem_type_str array to its only user
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>
2018-12-06 15:45:46 +01:00
Alexandre Belloni 1668845366 nvmem: add type attribute
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>
2018-12-06 15:45:45 +01:00
Bartosz Golaszewski 20167b70c8 nvmem: use EOPNOTSUPP instead of ENOSYS
Checkpatch emits warnings when using ENOSYS. Some of the frameworks
started using EOPNOTSUPP as return values for API functions when given
subsystem is disabled in Kconfig.

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>
2018-09-28 15:14:55 +02:00
Bartosz Golaszewski b1c1db9883 nvmem: use SPDX license identifiers
Use SPDX license identiefiers to core nvmem files and remove GPL 2.0
license boilerplate.

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>
2018-09-28 15:14:54 +02:00
Bartosz Golaszewski b985f4cba6 nvmem: add support for cell info
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>
2018-09-28 15:14:54 +02:00
Bartosz Golaszewski bf58e8820c nvmem: change the signature of nvmem_unregister()
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>
2018-09-28 15:14:54 +02:00
Andrew Lunn b3db17e4b8 drivers: nvmem: Export nvmem_add_cells()
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>
2018-05-14 16:20:48 +02:00
Andrey Smirnov f1f50eca5f nvmem: Introduce devm_nvmem_(un)register()
Introduce devm_nvmem_register()/devm_nvmem_unregister() to make
.remove() unnecessary in trivial drivers.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: cphealy@gmail.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-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>
2018-03-14 19:28:13 +01:00
Andrey Smirnov fd0f4906a3 nvmem: core: Allow specifying device name verbatim
Add code to allow avoid having nvmem core append a numeric suffix to
the end of the name by passing config->id of -1.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: cphealy@gmail.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-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>
2018-03-14 19:28:13 +01:00
Andrey Smirnov 0b2ed745e7 nvmem: Document struct nvmem_config
Add a simple description of struct nvmem_config and its fields.

Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: cphealy@gmail.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-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>
2018-03-14 19:28:13 +01:00
Arnd Bergmann 42a6e09960 nvmem: include linux/err.h from header
The new support for nvmem devices from the rtc layer caused a build
error in some configurations:

include/linux/nvmem-provider.h: In function 'nvmem_register':
include/linux/nvmem-provider.h:51:9: error: implicit declaration of function 'ERR_PTR' [-Werror=implicit-function-declaration]

This adds the missing include to ensure we can always include
the header.

Fixes: 697e5a47aa ("rtc: add generic nvmem support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
2017-07-10 14:27:39 +02:00
Srinivas Kandagatla 795ddd18d3 nvmem: core: remove regmap dependency
nvmem uses regmap_raw_read/write apis to read/write data from providers,
regmap raw apis stopped working with recent kernels which removed raw
accessors on mmio bus. This resulted in broken nvmem for providers
which are based on regmap mmio bus. This issue can be fixed temporarly
by moving to other regmap apis, but we might hit same issue in future.
Moving to interfaces based on read/write callbacks from providers would
be more robust.

This patch removes regmap dependency from nvmem and introduces
read/write callbacks from the providers.

Without this patch nvmem providers like qfprom based on regmap mmio
bus would not work.

Reported-by: Rajendra Nayak <rjendra@qti.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01 14:01:00 -07:00
Andrew Lunn b6c217ab9b nvmem: Add backwards compatibility support for older EEPROM drivers.
Older drivers made an 'eeprom' file available in the /sys device
directory. Have the NVMEM core provide this to retain backwards
compatibility.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01 16:55:48 -08:00
Andrew Lunn 811b0d6538 nvmem: Add flag to export NVMEM to root only
Legacy AT24, AT25 EEPROMs are exported in sys so that only root can
read the contents. The EEPROMs may contain sensitive information. Add
a flag so the provide can indicate that NVMEM should also restrict
access to root only.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-01 16:55:48 -08:00
Srinivas Kandagatla eace75cfdc nvmem: Add a simple NVMEM framework for nvmem providers
This patch adds just providers part of the framework just to enable easy
review.

Up until now, NVMEM drivers like eeprom were stored in drivers/misc,
where they all had to duplicate pretty much the same code to register
a sysfs file, allow in-kernel users to access the content of the devices
they were driving, etc.

This was also a problem as far as other in-kernel users were involved,
since the solutions used were pretty much different from on driver to
another, there was a rather big abstraction leak.

This introduction of this framework aims at solving this. It also
introduces DT representation for consumer devices to go get the data
they require (MAC Addresses, SoC/Revision ID, part numbers, and so on)
from the nvmems.

Having regmap interface to this framework would give much better
abstraction for nvmems on different buses.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
[Maxime Ripard: intial version of eeprom framework]
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-05 13:43:12 -07:00