Commit Graph

105 Commits

Author SHA1 Message Date
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
Vadym Kochan fc9eec4d64 nvmem: core: fix possibly memleak when use nvmem_cell_info_to_nvmem_cell()
Fix missing 'kfree_const(cell->name)' when call to
nvmem_cell_info_to_nvmem_cell() in several places:

     * after nvmem_cell_info_to_nvmem_cell() failed during
       nvmem_add_cells()

     * during nvmem_device_cell_{read,write} when cell->name is
       kstrdup'ed() without calling kfree_const() at the end, but
       really there is no reason to do that 'dup, because the cell
       instance is allocated on the stack for some short period to be
       read/write without exposing it to the caller.

So the new nvmem_cell_info_to_nvmem_cell_nodup() helper is introduced
which is used to convert cell_info -> cell without name duplication as
a lighweight version of nvmem_cell_info_to_nvmem_cell().

Fixes: e2a5402ec7 ("nvmem: Add nvmem_device based consumer apis.")
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Link: https://lore.kernel.org/r/20200923204456.14032-1-vadym.kochan@plvision.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-27 14:25:48 +02:00
Vadym Kochan b1c194dcdb nvmem: core: fix missing of_node_put() in of_nvmem_device_get()
of_parse_phandle() returns device_node with incremented ref count
which needs to be decremented by of_node_put() when device_node
is not used.

Fixes: e2a5402ec7 ("nvmem: Add nvmem_device based consumer apis.")
Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200917134437.16637-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 18:48:23 +02:00
Bartosz Golaszewski 1eb51d6a4f nvmem: switch to simpler IDA interface
We don't need to specify any ranges when allocating IDs so we can switch
to ida_alloc() and ida_free() instead of the ida_simple_ counterparts.

ida_simple_get(ida, 0, 0, gfp) is equivalent to
ida_alloc_range(ida, 0, UINT_MAX, gfp) which is equivalent to
ida_alloc(ida, gfp). Note: IDR will never actually allocate an ID
larger than INT_MAX.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200917134437.16637-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 18:48:23 +02:00
Tian Tao 28371cc610 nvmem: core: Use kobj_to_dev() instead of container_of()
Use kobj_to_dev() instead of container_of()

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200917134437.16637-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-17 18:48:23 +02:00
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
Andreas Färber 5037d368b2 nvmem: core: Add nvmem_cell_read_u8()
Complement the u16, u32 and u64 helpers with a u8 variant to ease
accessing byte-sized values.

This helper will be useful for Realtek Digital Home Center platforms,
which store some byte and sub-byte sized values in non-volatile memory.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 17:12:08 +02:00
Andreas Färber 3a7580710b nvmem: core: Grammar fixes for help text
It's "an unsigned" but "a U".
Similarly, "an entry" but "a binary entry".

While at it, also drop superfluous articles for negative and zero.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 17:12:08 +02:00
Douglas Anderson 8356671574 nvmem: Enforce nvmem stride in the sysfs interface
The 'struct nvmem_config' has a stride attribute that specifies the
needed alignment for accesses into the nvmem.  This is used in
nvmem_cell_info_to_nvmem_cell() but not in the sysfs read/write
functions.  If the alignment is important in one place it's important
everywhere, so let's add enforcement.

For now we'll consider it totally invalid to access with the wrong
alignment.  We could relax this in the read case where we could just
read some extra bytes and throw them away.  Relaxing it in the write
case seems harder (and less safe?) since we'd have to read some data
first and then write it back.  To keep it symmetric we'll just
disallow it in both cases.

Reported-by: Ravi Kumar Bokka <rbokka@codeaurora.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Ravi Kumar Bokka <rbokka@codeaurora.org>
Tested-by: Ravi Kumar Bokka <rbokka@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200722100705.7772-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 17:12:08 +02:00
Michael Auchter b96fc5416b nvmem: ensure sysfs writes handle write-protect pin
Commit 2a127da461 ("nvmem: add support for the write-protect pin")
added support for handling write-protect pins to the nvmem core, and
Commit 1c89074bf8 ("eeprom: at24: remove the write-protect pin support")
retrofitted the at24 driver to use this support.

These changes broke write() on the nvmem sysfs attribute for eeproms
which utilize a write-protect pin, as the write callback invokes the
nvmem device's reg_write callback directly which no longer handles
changing the state of the write-protect pin.

Change the read and write callbacks for the sysfs attribute to invoke
nvmme_reg_read/nvmem_reg_write helpers which handle this, rather than
calling reg_read/reg_write directly.

Fixes: 2a127da461 ("nvmem: add support for the write-protect pin")
Signed-off-by: Michael Auchter <michael.auchter@ni.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200511145042.31223-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-15 16:20:02 +02:00
Srinivas Kandagatla 2a4542e55f nvmem: core: cleanup old eeprom compat entry attributes
file permission are derived based on various configs for
default nvmem sysfs file, reuse it to create the eeprom
compat file too.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200417121306.23121-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-28 15:02:48 +02:00
Srinivas Kandagatla 8440030527 nvmem: core: remove nvmem_sysfs_get_groups()
Now that we are using is_bin_visible callback, we do not need
nvmem_sysfs_get_groups() anymore so move all the relevant data-structures
and code to core.c

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200325131951.31887-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 19:23:49 +01:00
Srinivas Kandagatla 664f054938 nvmem: core: use is_bin_visible for permissions
By using is_bin_visible callback to set permissions will remove a
large list of attribute groups. These group permissions can be
dynamically derived in the callback.

Also add checks for read/write callbacks and set permissions accordingly.

Suggested-by: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200325131951.31887-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 19:23:48 +01:00
Srinivas Kandagatla f60442ddc4 nvmem: core: use device_register and device_unregister
use device_register/unregister instead of spliting them with no use.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200324171600.15606-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 18:56:38 +01:00
Srinivas Kandagatla e6de179d7a nvmem: core: add root_only member to nvmem device struct
As we are planning to move to use sysfs is_bin_visible callback,
having root_only as part of nvmem_device will help decide correct
permissions.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200325122116.15096-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 13:45:09 +01:00
Srinivas Kandagatla 061a320b32 nvmem: core: validate nvmem config before parsing
nvmem provider has to provide either reg_read/write, add a check
to enforce this.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:03 +01:00
Khouloud Touil a9c3766cb1 nvmem: release the write-protect pin
Put the write-protect GPIO descriptor in nvmem_release() so that it can
be automatically released when the associated device's reference count
drops to 0.

Fixes: 2a127da461 ("nvmem: add support for the write-protect pin")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Khouloud Touil <ktouil@baylibre.com>
Cc: stable <stable@vger.kernel.org>
[Bartosz: tweak the commit message]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:03 +01:00
Bartosz Golaszewski f7d8d7dcd9 nvmem: fix memory leak in error path
We need to free the ida mapping and nvmem struct if the write-protect
GPIO lookup fails.

Fixes: 2a127da461 ("nvmem: add support for the write-protect pin")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:02 +01:00
Bartosz Golaszewski 31c6ff51fd nvmem: add a newline for readability
Visibly separate the GPIO request from the previous operation in the
code with a newline.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:02 +01:00
Bartosz Golaszewski e280a8c64a nvmem: remove a stray newline in nvmem_register()
Two newlines are unnecessary - remove one.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:02 +01:00
Yangtao Li 8b977c5498 nvmem: core: add nvmem_cell_read_u64
Add nvmem_cell_read_u64() helper to ease read of an u64 value on consumer
side. This helper is useful on some sunxi platform that has 64 bits data
cells stored in no volatile memory.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:02 +01:00
Yangtao Li 6bb317ce75 nvmem: core: add nvmem_cell_read_common
Now there are nvmem_cell_read_u16 and nvmem_cell_read_u32.
They are very similar, let's strip out a common part.

And use nvmem_cell_read_common to simplify their implementation.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200310132257.23358-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-19 07:41:02 +01:00
Linus Torvalds 11777ee8b0 Merge branch 'i2c/for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "i2c core:

   - huge improvements and refactorizations of the Linux I2C
     documentation (lots of thanks to Luca for doing it and Jean for the
     careful review)

   - subsystem wide API conversion to i2c_new_client_device()

   - remove obsolete parport-light driver

   - smaller core updates (removal of 'extern', enabling more compile
     testing, use more helper macros)

   - and quite a bunch of driver updates (new IDs, simplifications,
     better PM, support of atomic transfers and other improvements)

  i2c-mux:

   - The main feature is the idle-state rework of the pca954x driver
     from Biwen Li

  at24 driver:

   - minor maintenance: update the license tag, sort headers

   - move support for the write-protect pin into nvmem core

   - add a reference to the new wp-gpios property in nvmem to at25
     bindings

   - add support for regulator and pm_runtime control"

* 'i2c/for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (91 commits)
  i2c: cros-ec-tunnel: Fix ACPI identifier
  i2c: cros-ec-tunnel: Fix slave device enumeration
  i2c: stm32f7: add PM_SLEEP suspend/resume support
  i2c: cadence: Fix wording in i2c-cadence driver
  i2c: cadence: Fix power management order of operations
  i2c: cadence: Fix error printing in case of defer
  i2c: cadence: Handle transfer_size rollover
  i2c: i801: Add support for Intel Comet Lake PCH-V
  docs: i2c: writing-clients: properly name the stop condition
  docs: i2c: i2c-protocol: use same wording as smbus-protocol
  docs: i2c: rename sections so the overall picture is clearer
  docs: i2c: old-module-parameters: use monospace instead of ""
  docs: i2c: old-module-parameters: clarify this is for obsolete kernels
  docs: i2c: old-module-parameters: fix internal hyperlink
  docs: i2c: instantiating-devices: use monospace for sysfs attributes
  docs: i2c: instantiating-devices: rearrange static instatiation
  docs: i2c: instantiating-devices: fix internal hyperlink
  docs: i2c: smbus-protocol: improve I2C Block transactions description
  docs: i2c: smbus-protocol: fix punctuation
  docs: i2c: smbus-protocol: fix typo
  ...
2020-02-07 12:54:13 -08:00
Bitan Biswas 16bb7abc4a nvmem: core: fix memory abort in cleanup path
nvmem_cell_info_to_nvmem_cell implementation has static
allocation of name. nvmem_add_cells_from_of() call may
return error and kfree name results in memory abort. Use
kstrdup_const() and kfree_const calls for name alloc and free.

Unable to handle kernel paging request at virtual address ffffffffffe44888
Mem abort info:
  ESR = 0x96000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
swapper pgtable: 64k pages, 48-bit VAs, pgdp=00000000815d0000
[ffffffffffe44888] pgd=0000000081d30803, pud=0000000081d30803,
pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 43 Comm: kworker/2:1 Tainted
Hardware name: quill (DT)
Workqueue: events deferred_probe_work_func
pstate: a0000005 (NzCv daif -PAN -UAO)
pc : kfree+0x38/0x278
lr : nvmem_cell_drop+0x68/0x80
sp : ffff80001284f9d0
x29: ffff80001284f9d0 x28: ffff0001f677e830
x27: ffff800011b0b000 x26: ffff0001c36e1008
x25: ffff8000112ad000 x24: ffff8000112c9000
x23: ffffffffffffffea x22: ffff800010adc7f0
x21: ffffffffffe44880 x20: ffff800011b0b068
x19: ffff80001122d380 x18: ffffffffffffffff
x17: 00000000d5cb4756 x16: 0000000070b193b8
x15: ffff8000119538c8 x14: 0720072007200720
x13: 07200720076e0772 x12: 07750762072d0765
x11: 0773077507660765 x10: 072f073007300730
x9 : 0730073207380733 x8 : 0000000000000151
x7 : 07660765072f0720 x6 : ffff0001c00e0f00
x5 : 0000000000000000 x4 : ffff0001c0b43800
x3 : ffff800011b0b068 x2 : 0000000000000000
x1 : 0000000000000000 x0 : ffffffdfffe00000
Call trace:
 kfree+0x38/0x278
 nvmem_cell_drop+0x68/0x80
 nvmem_device_remove_all_cells+0x2c/0x50
 nvmem_register.part.9+0x520/0x628
 devm_nvmem_register+0x48/0xa0
 tegra_fuse_probe+0x140/0x1f0
 platform_drv_probe+0x50/0xa0
 really_probe+0x108/0x348
 driver_probe_device+0x58/0x100
 __device_attach_driver+0x90/0xb0
 bus_for_each_drv+0x64/0xc8
 __device_attach+0xd8/0x138
 device_initial_probe+0x10/0x18
 bus_probe_device+0x90/0x98
 deferred_probe_work_func+0x74/0xb0
 process_one_work+0x1e0/0x358
 worker_thread+0x208/0x488
 kthread+0x118/0x120
 ret_from_fork+0x10/0x18
Code: d350feb5 f2dffbe0 aa1e03f6 8b151815 (f94006a0)
---[ end trace 49b1303c6b83198e ]---

Fixes: badcdff107 ("nvmem: Convert to using %pOFn instead of device_node.name")
Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200109104017.6249-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-10 13:52:13 +01:00
Bartosz Golaszewski a99d2c6ccd nvmem: fix a 'makes pointer from integer without a cast' build warning
nvmem_register() returns a pointer, not a long int. Use ERR_CAST() to
cast the struct gpio_desc pointer to struct nvmem_device.

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 2a127da461 ("nvmem: add support for the write-protect pin")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
2020-01-10 12:11:30 +01:00
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
Thomas Bogendoerfer 8c2a2b8c2f
nvmem: core: add nvmem_device_find
nvmem_device_find provides a way to search for nvmem devices with
the help of a match function simlair to bus_find_device.

Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: linux-serial@vger.kernel.org
2019-10-07 09:47:37 -07:00
Suzuki K Poulose cfba5de9b9 drivers: Introduce device lookup variants by of_node
Introduce wrappers for {bus/driver/class}_find_device() to
locate devices by its of_node.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: dri-devel@lists.freedesktop.org
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: devicetree@vger.kernel.org
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: linux-i2c@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-spi@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Alan Tull <atull@kernel.org>
Cc: linux-fpga@vger.kernel.org
Cc: Peter Rosin <peda@axentia.se>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Thor Thayer <thor.thayer@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Peter Rosin <peda@axentia.se>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # I2C part
Acked-by: Moritz Fischer <mdf@kernel.org> # For FPGA part
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20190723221838.12024-3-suzuki.poulose@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-30 13:07:41 +02:00
Suzuki K Poulose 418e3ea157 bus_find_device: Unify the match callback with class_find_device
There is an arbitrary difference between the prototypes of
bus_find_device() and class_find_device() preventing their callers
from passing the same pair of data and match() arguments to both of
them, which is the const qualifier used in the prototype of
class_find_device().  If that qualifier is also used in the
bus_find_device() prototype, it will be possible to pass the same
match() callback function to both bus_find_device() and
class_find_device(), which will allow some optimizations to be made in
order to avoid code duplication going forward.  Also with that, constify
the "data" parameter as it is passed as a const to the match function.

For this reason, change the prototype of bus_find_device() to match
the prototype of class_find_device() and adjust its callers to use the
const qualifier in accordance with the new prototype of it.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Kershner <david.kershner@unisys.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Harald Freudenberger <freude@linux.ibm.com>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Jamet <michael.jamet@intel.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Sebastian Ott <sebott@linux.ibm.com>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Yehezkel Bernat <YehezkelShB@gmail.com>
Cc: rafael@kernel.org
Acked-by: Corey Minyard <minyard@acm.org>
Acked-by: David Kershner <david.kershner@unisys.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # for the I2C parts
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-24 05:22:31 +02:00
Srinivas Kandagatla ae0c2d7255 nvmem: core: add NVMEM_SYSFS Kconfig
Many nvmem providers are not very keen on having default sysfs
nvmem entry, as most of the usecases for them are inside kernel
itself. And in some cases read/writes to some areas in nvmem are
restricted and trapped at secure monitor level, so accessing them
from userspace would result in board reboots.

This patch adds new NVMEM_SYSFS Kconfig to make binary sysfs entry
an optional one. This provision will give more flexibility to users.
This patch also moves existing sysfs code to a new file so that its
not compiled in when its not really required.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Gaurav Kohli <gkohli@codeaurora.org>
Tested-by: Gaurav Kohli <gkohli@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 19:44:33 +02:00
Jorge Ramirez-Ortiz 2fe518fecb nvmem: core: fix read buffer in place
When the bit_offset in the cell is zero, the pointer to the msb will
not be properly initialized (ie, will still be pointing to the first
byte in the buffer).

This being the case, if there are bits to clear in the msb, those will
be left untouched while the mask will incorrectly clear bit positions
on the first byte.

This commit also makes sure that any byte unused in the cell is
cleared.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 19:43:12 +02:00
Fabrice Gasnier 0a9b2d1ce4 nvmem: core: add nvmem_cell_read_u16
Add nvmem_cell_read_u16() helper to ease read of an u16 value on consumer
side. This is inspired by nvmem_cell_read_u32() function.
This helper is useful on stm32 that has 16 bits data cells stored in non
volatile memory.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25 19:43:12 +02:00
Bartosz Golaszewski f4853e1c32 nvmem: core: don't check the return value of notifier chain call
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>
2019-02-19 14:50:11 +01:00
Alban Bedel 9bfd8198ba nvmem: core: Avoid useless iterations in nvmem_cell_get_from_lookup()
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>
2019-01-31 16:24:15 +01:00
Alban Bedel 73e9dc4d56 nvmem: core: Fix device reference leak
__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>
2019-01-31 16:24:15 +01:00
Alban Bedel 95b65195d5 nvmem: core: Always reference the device returned by nvmem_device_get()
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>
2019-01-31 16:24:14 +01:00
Alban Bedel d4e7fef1a9 nvmem: core: Properly handle connection ID in of_nvmem_device_get()
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>
2019-01-31 16:24:14 +01:00
Alban Bedel 1c83267473 nvmem: core: Fix cell lookup when no cell is found
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>
2019-01-31 16:24:14 +01:00
Alban Bedel 5087cc198e nvmem: core: Fix of_nvmem_cell_get() for optional cells
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>
2019-01-31 16:24:14 +01:00
Alban Bedel 1716cfe8be nvmem: core: Set the provider read-only when no write callback is given
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>
2019-01-31 16:24:14 +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
Srinivas Kandagatla 0749aa25af nvmem: core: fix regression in of_nvmem_cell_get()
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>
2018-11-11 09:15:29 -08:00
Arnd Bergmann 3c53e2352a nvmem: hide unused nvmem_find_cell_by_index function
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>
2018-10-15 15:56:15 +02:00
Bartosz Golaszewski cccb3b19e7 nvmem: fix nvmem_cell_get_from_lookup()
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>
2018-10-15 15:56:15 +02:00
Rob Herring badcdff107 nvmem: Convert to using %pOFn instead of device_node.name
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>
2018-10-15 15:56:14 +02:00
Srinivas Kandagatla ef92ab3001 nvmem: make nvmem_add_cells() static
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>
2018-09-28 15:14:55 +02:00
Bartosz Golaszewski e7e07f4f7b nvmem: use octal permissions instead of constants
Checkpatch emits a warning when using symbolic permissions. Use octal
permissions 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>
2018-09-28 15:14:55 +02:00
Bartosz Golaszewski 48f63a2c10 nvmem: fix commenting style
Remove a redundant '*/' as pointed out by checkpatch.

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