linux-stable.git/drivers/regulator, branch v5.4.252

regulator: core: Streamline debugfs operations

2023-07-27T06:37:07+00:00

[ Upstream commit 08880713ceec023dd94d634f1e8902728c385939 ]

If CONFIG_DEBUG_FS is not set:

    regulator: Failed to create debugfs directory
    ...
    regulator-dummy: Failed to create debugfs directory

As per the comments for debugfs_create_dir(), errors returned by this
function should be expected, and ignored:

 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
 * returned.
 *
 * NOTE: it's expected that most callers should _ignore_ the errors returned
 * by this function. Other debugfs functions handle the fact that the "dentry"
 * passed to them could be an error and they don't crash in that case.
 * Drivers should generally work fine even if debugfs fails to init anyway.

Adhere to the debugfs spirit, and streamline all operations by:
  1. Demoting the importance of the printed error messages to debug
     level, like is already done in create_regulator(),
  2. Further ignoring any returned errors, as by design, all debugfs
     functions are no-ops when passed an error pointer.

Fixes: 2bf1c45be3b8f3a3 ("regulator: Fix error checking for debugfs_create_dir")
Signed-off-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/2f8bb6e113359ddfab7b59e4d4274bd4c06d6d0a.1685013051.git.geert+renesas@glider.be
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: core: Fix more error checking for debugfs_create_dir()

2023-07-27T06:37:07+00:00

[ Upstream commit 2715bb11cfff964aa33946847f9527cfbd4874f5 ]

In case of failure, debugfs_create_dir() does not return NULL, but an
error pointer.  Most incorrect error checks were fixed, but the one in
create_regulator() was forgotten.

Fix the remaining error check.

Fixes: 2bf1c45be3b8f3a3 ("regulator: Fix error checking for debugfs_create_dir")
Signed-off-by: Geert Uytterhoeven 
Link: https://lore.kernel.org/r/ee980a108b5854dd8ce3630f8f673e784e057d17.1685013051.git.geert+renesas@glider.be
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: Fix error checking for debugfs_create_dir

2023-06-21T13:44:09+00:00

[ Upstream commit 2bf1c45be3b8f3a3f898d0756c1282f09719debd ]

This patch fixes the error checking in core.c in debugfs_create_dir.
The correct way to check if an error occurred is 'IS_ERR' inline function.

Signed-off-by: Osama Muhammad

regulator: stm32-pwr: fix of_iomap leak

2023-05-17T09:35:38+00:00

[ Upstream commit c4a413e56d16a2ae84e6d8992f215c4dcc7fac20 ]

Smatch reports:
drivers/regulator/stm32-pwr.c:166 stm32_pwr_regulator_probe() warn:
'base' from of_iomap() not released on lines: 151,166.

In stm32_pwr_regulator_probe(), base is not released
when devm_kzalloc() fails to allocate memory or
devm_regulator_register() fails to register a new regulator device,
which may cause a leak.

To fix this issue, replace of_iomap() with
devm_platform_ioremap_resource(). devm_platform_ioremap_resource()
is a specialized function for platform devices.
It allows 'base' to be automatically released whether the probe
function succeeds or fails.

Besides, use IS_ERR(base) instead of !base
as the return value of devm_platform_ioremap_resource()
can either be a pointer to the remapped memory or
an ERR_PTR() encoded error code if the operation fails.

Fixes: dc62f951a6a8 ("regulator: stm32-pwr: Fix return value check in stm32_pwr_regulator_probe()")
Signed-off-by: YAN SHI 
Reported-by: kernel test robot 
Link: https://lore.kernel.org/oe-kbuild-all/202304111750.o2643eJN-lkp@intel.com/
Reviewed-by: Dongliang Mu 
Link: https://lore.kernel.org/r/20230412033529.18890-1-m202071378@hust.edu.cn
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: core: Avoid lockdep reports when resolving supplies

2023-05-17T09:35:37+00:00

[ Upstream commit cba6cfdc7c3f1516f0d08ddfb24e689af0932573 ]

An automated bot told me that there was a potential lockdep problem
with regulators. This was on the chromeos-5.15 kernel, but I see
nothing that would be different downstream compared to upstream. The
bot said:
  ============================================
  WARNING: possible recursive locking detected
  5.15.104-lockdep-17461-gc1e499ed6604 #1 Not tainted
  --------------------------------------------
  kworker/u16:4/115 is trying to acquire lock:
  ffffff8083110170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: create_regulator+0x398/0x7ec

  but task is already holding lock:
  ffffff808378e170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: ww_mutex_trylock+0x3c/0x7b8

  other info that might help us debug this:
   Possible unsafe locking scenario:

         CPU0
         ----
    lock(regulator_ww_class_mutex);
    lock(regulator_ww_class_mutex);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  4 locks held by kworker/u16:4/115:
   #0: ffffff808006a948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x520/0x1348
   #1: ffffffc00e0a7cc0 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x55c/0x1348
   #2: ffffff80828a2260 (&dev->mutex){....}-{3:3}, at: __device_attach_async_helper+0xd0/0x2a4
   #3: ffffff808378e170 (regulator_ww_class_mutex){+.+.}-{3:3}, at: ww_mutex_trylock+0x3c/0x7b8

  stack backtrace:
  CPU: 2 PID: 115 Comm: kworker/u16:4 Not tainted 5.15.104-lockdep-17461-gc1e499ed6604 #1 9292e52fa83c0e23762b2b3aa1bacf5787a4d5da
  Hardware name: Google Quackingstick (rev0+) (DT)
  Workqueue: events_unbound async_run_entry_fn
  Call trace:
   dump_backtrace+0x0/0x4ec
   show_stack+0x34/0x50
   dump_stack_lvl+0xdc/0x11c
   dump_stack+0x1c/0x48
   __lock_acquire+0x16d4/0x6c74
   lock_acquire+0x208/0x750
   __mutex_lock_common+0x11c/0x11f8
   ww_mutex_lock+0xc0/0x440
   create_regulator+0x398/0x7ec
   regulator_resolve_supply+0x654/0x7c4
   regulator_register_resolve_supply+0x30/0x120
   class_for_each_device+0x1b8/0x230
   regulator_register+0x17a4/0x1f40
   devm_regulator_register+0x60/0xd0
   reg_fixed_voltage_probe+0x728/0xaec
   platform_probe+0x150/0x1c8
   really_probe+0x274/0xa20
   __driver_probe_device+0x1dc/0x3f4
   driver_probe_device+0x78/0x1c0
   __device_attach_driver+0x1ac/0x2c8
   bus_for_each_drv+0x11c/0x190
   __device_attach_async_helper+0x1e4/0x2a4
   async_run_entry_fn+0xa0/0x3ac
   process_one_work+0x638/0x1348
   worker_thread+0x4a8/0x9c4
   kthread+0x2e4/0x3a0
   ret_from_fork+0x10/0x20

The problem was first reported soon after we made many of the
regulators probe asynchronously, though nothing I've seen implies that
the problems couldn't have also happened even without that.

I haven't personally been able to reproduce the lockdep issue, but the
issue does look somewhat legitimate. Specifically, it looks like in
regulator_resolve_supply() we are holding a "rdev" lock while calling
set_supply() -> create_regulator() which grabs the lock of a
_different_ "rdev" (the one for our supply). This is not necessarily
safe from a lockdep perspective since there is no documented ordering
between these two locks.

In reality, we should always be locking a regulator before the
supplying regulator, so I don't expect there to be any real deadlocks
in practice. However, the regulator framework in general doesn't
express this to lockdep.

Let's fix the issue by simply grabbing the two locks involved in the
same way we grab multiple locks elsewhere in the regulator framework:
using the "wound/wait" mechanisms.

Fixes: eaa7995c529b ("regulator: core: avoid regulator_resolve_supply() race condition")
Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.2.I30d8e1ca10cfbe5403884cdd192253a2e063eb9e@changeid
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: core: Consistently set mutex_owner when using ww_mutex_lock_slow()

2023-05-17T09:35:37+00:00

[ Upstream commit b83a1772be854f87602de14726737d3e5b06e1f4 ]

When a codepath locks a rdev using ww_mutex_lock_slow() directly then
that codepath is responsible for incrementing the "ref_cnt" and also
setting the "mutex_owner" to "current".

The regulator core consistently got that right for "ref_cnt" but
didn't always get it right for "mutex_owner". Let's fix this.

It's unlikely that this truly matters because the "mutex_owner" is
only needed if we're going to do subsequent locking of the same
rdev. However, even though it's not truly needed it seems less
surprising if we consistently set "mutex_owner" properly.

Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.1.I4e9d433ea26360c06dd1381d091c82bb1a4ce843@changeid
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: fan53555: Explicitly include bits header

2023-04-26T09:24:01+00:00

[ Upstream commit 4fb9a5060f73627303bc531ceaab1b19d0a24aef ]

Since commit f2a9eb975ab2 ("regulator: fan53555: Add support for
FAN53526") the driver makes use of the BIT() macro, but relies on the
bits header being implicitly included.

Explicitly pull the header in to avoid potential build failures in some
configurations.

While here, reorder include directives alphabetically.

Fixes: f2a9eb975ab2 ("regulator: fan53555: Add support for FAN53526")
Signed-off-by: Cristian Ciocaltea 
Link: https://lore.kernel.org/r/20230406171806.948290-3-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: Handle deferred clk

2023-04-05T09:16:44+00:00

[ Upstream commit 02bcba0b9f9da706d5bd1e8cbeb83493863e17b5 ]

devm_clk_get() can return -EPROBE_DEFER. So it is better to return the
error code from devm_clk_get(), instead of a hard coded -ENOENT.

This gives more opportunities to successfully probe the driver.

Fixes: 8959e5324485 ("regulator: fixed: add possibility to enable by clock")
Signed-off-by: Christophe JAILLET 
Link: https://lore.kernel.org/r/18459fae3d017a66313699c7c8456b28158b2dd0.1679819354.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin

regulator: fix spelling mistake "Cant" -> "Can't"

2023-04-05T09:16:43+00:00

[ Upstream commit 09dad81e0f1701ea26babe2442a1478d6ad447d3 ]

There is a spelling mistake in a dev_err message. Fix it.

Signed-off-by: Colin Ian King 
Link: https://lore.kernel.org/r/20200810093931.50624-1-colin.king@canonical.com
Signed-off-by: Mark Brown 
Stable-dep-of: 02bcba0b9f9d ("regulator: Handle deferred clk")
Signed-off-by: Sasha Levin

regulator: s5m8767: Bounds check id indexing into arrays

2023-03-11T15:43:57+00:00

[ Upstream commit e314e15a0b58f9d051c00b25951073bcdae61953 ]

The compiler has no way to know if "id" is within the array bounds of
the regulators array. Add a check for this and a build-time check that
the regulators and reg_voltage_map arrays are sized the same. Seen with
GCC 13:

../drivers/regulator/s5m8767.c: In function 's5m8767_pmic_probe':
../drivers/regulator/s5m8767.c:936:35: warning: array subscript [0, 36] is outside array bounds of 'struct regulator_desc[37]' [-Warray-bounds=]
  936 |                         regulators[id].vsel_reg =
      |                         ~~~~~~~~~~^~~~

Cc: Krzysztof Kozlowski 
Cc: Liam Girdwood 
Cc: Mark Brown 
Cc: linux-samsung-soc@vger.kernel.org
Signed-off-by: Kees Cook 
Reviewed-by: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20230128005358.never.313-kees@kernel.org
Signed-off-by: Mark Brown 
Signed-off-by: Sasha Levin