linux-stable.git/drivers/nvmem/core.c, branch linux-5.17.y

nvmem: core: Fix a conflict between MTD and NVMEM on wp-gpios property

2022-02-21T16:59:25+00:00

Wp-gpios property can be used on NVMEM nodes and the same property can
be also used on MTD NAND nodes. In case of the wp-gpios property is
defined at NAND level node, the GPIO management is done at NAND driver
level. Write protect is disabled when the driver is probed or resumed
and is enabled when the driver is released or suspended.

When no partitions are defined in the NAND DT node, then the NAND DT node
will be passed to NVMEM framework. If wp-gpios property is defined in
this node, the GPIO resource is taken twice and the NAND controller
driver fails to probe.

It would be possible to set config->wp_gpio at MTD level before calling
nvmem_register function but NVMEM framework will toggle this GPIO on
each write when this GPIO should only be controlled at NAND level driver
to ensure that the Write Protect has not been enabled.

A way to fix this conflict is to add a new boolean flag in nvmem_config
named ignore_wp. In case ignore_wp is set, the GPIO resource will
be managed by the provider.

Fixes: 2a127da461a9 ("nvmem: add support for the write-protect pin")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Kerello 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20220220151432.16605-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: set size for sysfs bin file

2021-12-03T15:03:37+00:00

For some reason we never set the size for nvmem sysfs binary file.
Set this.

Reported-by: Gilles BULOZ 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20211130133909.6154-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

Merge 5.15-rc6 into char-misc-next

2021-10-18T07:29:27+00:00

We need the char/misc fixes in here for merging and testing.

Signed-off-by: Greg Kroah-Hartman

nvmem: core: add nvmem cell post processing callback

2021-10-13T13:33:17+00:00

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 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20211013131957.30271-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: rework nvmem cell instance creation

2021-10-13T13:33:17+00:00

In the existing design, we do not create a instance per nvmem cell consumer
but we directly refer cell from nvmem cell list that are added to provider.

However this design has some limitations when consumers want to assign name
or connection id the nvmem cell instance, ex: via "nvmem-cell-names" or
id in nvmem_cell_get(id).

Having a name associated with nvmem cell consumer instance will help
provider drivers in performing post processing of nvmem cell data if required
before data is seen by the consumers. This is pretty normal with some vendors
storing nvmem cells like mac-address in a vendor specific data layouts that
are not directly usable by the consumer drivers.

With this patch nvmem cell will be created dynamically during nvmem_cell_get
and destroyed in nvmem_cell_put, allowing consumers to associate name with
nvmem cell consumer instance.

With this patch a new struct nvmem_cell_entry replaces struct nvmem_cell
for storing nvmem cell information within the core.
This patch does not change nvmem-consumer interface based on nvmem_cell.

Tested-by: Joakim Zhang 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20211013131957.30271-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells

2021-10-13T13:09:58+00:00

If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic

 *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);

will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we
subtract one from that making a large number that is then shifted more than the
number of bits that fit into an unsigned long.

UBSAN reports this problem:

 UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8
 shift exponent 64 is too large for 64-bit type 'unsigned long'
 CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9
 Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  dump_backtrace+0x0/0x170
  show_stack+0x24/0x30
  dump_stack_lvl+0x64/0x7c
  dump_stack+0x18/0x38
  ubsan_epilogue+0x10/0x54
  __ubsan_handle_shift_out_of_bounds+0x180/0x194
  __nvmem_cell_read+0x1ec/0x21c
  nvmem_cell_read+0x58/0x94
  nvmem_cell_read_variable_common+0x4c/0xb0
  nvmem_cell_read_variable_le_u32+0x40/0x100
  a6xx_gpu_init+0x170/0x2f4
  adreno_bind+0x174/0x284
  component_bind_all+0xf0/0x264
  msm_drm_bind+0x1d8/0x7a0
  try_to_bring_up_master+0x164/0x1ac
  __component_add+0xbc/0x13c
  component_add+0x20/0x2c
  dp_display_probe+0x340/0x384
  platform_probe+0xc0/0x100
  really_probe+0x110/0x304
  __driver_probe_device+0xb8/0x120
  driver_probe_device+0x4c/0xfc
  __device_attach_driver+0xb0/0x128
  bus_for_each_drv+0x90/0xdc
  __device_attach+0xc8/0x174
  device_initial_probe+0x20/0x2c
  bus_probe_device+0x40/0xa4
  deferred_probe_work_func+0x7c/0xb8
  process_one_work+0x128/0x21c
  process_scheduled_works+0x40/0x54
  worker_thread+0x1ec/0x2a8
  kthread+0x138/0x158
  ret_from_fork+0x10/0x20

Fix it by making sure there are any bits to mask out.

Fixes: 69aba7948cbe ("nvmem: Add a simple NVMEM framework for consumers")
Cc: Douglas Anderson 
Cc: stable@vger.kernel.org
Signed-off-by: Stephen Boyd 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20211013124511.18726-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: fix error handling while validating keepout regions

2021-08-06T13:18:40+00:00

Current error path on failure of validating keepout regions is calling
put_device, eventhough the device is not even registered at that point.

Fix this by adding proper error handling of freeing ida and nvmem.

Fixes: fd3bb8f54a88 ("nvmem: core: Add support for keepout regions")
Cc: 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20210806085947.22682-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2021-07-05T20:42:16+00:00

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
  ...

nvmem: core: add a missing of_node_put

2021-06-11T10:34:04+00:00

'for_each_child_of_node' performs an of_node_get on each iteration, so a
return from the middle of the loop requires an of_node_put.

Fixes: e888d445ac33 ("nvmem: resolve cells from DT at registration time")
Cc: 
Signed-off-by: Christophe JAILLET 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20210611102321.11509-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: prepare basics for FRAM support

2021-06-11T10:23:10+00:00

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 
Link: https://lore.kernel.org/r/20210611094601.95131-2-jiri.prchal@aksignal.cz
Signed-off-by: Greg Kroah-Hartman