<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/regulator, branch v6.3.8</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>regulator: mt6359: add read check for PMIC MT6359</title>
<updated>2023-05-30T13:17:28+00:00</updated>
<author>
<name>Sen Chu</name>
<email>sen.chu@mediatek.com</email>
</author>
<published>2023-05-18T04:06:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=85c45023adaba01ddb42c8f9a4384ec253d53632'/>
<id>85c45023adaba01ddb42c8f9a4384ec253d53632</id>
<content type='text'>
commit a511637502b1caa135046d0f8fdabd55a31af8ef upstream.

Add hardware version read check for PMIC MT6359

Signed-off-by: Sen Chu &lt;sen.chu@mediatek.com
Fixes: 4cfc96547512 ("regulator: mt6359: Add support for MT6359P regulator")
Reviewed-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com
Link: https://lore.kernel.org/r/20230518040646.8730-1-sen.chu@mediatek.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a511637502b1caa135046d0f8fdabd55a31af8ef upstream.

Add hardware version read check for PMIC MT6359

Signed-off-by: Sen Chu &lt;sen.chu@mediatek.com
Fixes: 4cfc96547512 ("regulator: mt6359: Add support for MT6359P regulator")
Reviewed-by: AngeloGioacchino Del Regno &lt;angelogioacchino.delregno@collabora.com
Link: https://lore.kernel.org/r/20230518040646.8730-1-sen.chu@mediatek.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: pca9450: Fix BUCK2 enable_mask</title>
<updated>2023-05-30T13:17:26+00:00</updated>
<author>
<name>Alexander Stein</name>
<email>alexander.stein@ew.tq-group.com</email>
</author>
<published>2023-05-12T08:19:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a8a1c9a127c843d6583e884c06d5c68bfba30c1f'/>
<id>a8a1c9a127c843d6583e884c06d5c68bfba30c1f</id>
<content type='text'>
commit d67dada3e2524514b09496b9ee1df22d4507a280 upstream.

This fixes a copy &amp; paste error.
No functional change intended, BUCK1_ENMODE_MASK equals BUCK2_ENMODE_MASK.

Fixes: 0935ff5f1f0a ("regulator: pca9450: add pca9450 pmic driver")
Originally-from: Robin Gong &lt;yibin.gong@nxp.com
Signed-off-by: Alexander Stein &lt;alexander.stein@ew.tq-group.com
Reviewed-by: Frieder Schrempf &lt;frieder.schrempf@kontron.de
Link: https://lore.kernel.org/r/20230512081935.2396180-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d67dada3e2524514b09496b9ee1df22d4507a280 upstream.

This fixes a copy &amp; paste error.
No functional change intended, BUCK1_ENMODE_MASK equals BUCK2_ENMODE_MASK.

Fixes: 0935ff5f1f0a ("regulator: pca9450: add pca9450 pmic driver")
Originally-from: Robin Gong &lt;yibin.gong@nxp.com
Signed-off-by: Alexander Stein &lt;alexander.stein@ew.tq-group.com
Reviewed-by: Frieder Schrempf &lt;frieder.schrempf@kontron.de
Link: https://lore.kernel.org/r/20230512081935.2396180-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: stm32-pwr: fix of_iomap leak</title>
<updated>2023-05-11T14:17:09+00:00</updated>
<author>
<name>YAN SHI</name>
<email>m202071378@hust.edu.cn</email>
</author>
<published>2023-04-12T03:35:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0ad07e02be0d3f0d554653382ffe53ae4879378d'/>
<id>0ad07e02be0d3f0d554653382ffe53ae4879378d</id>
<content type='text'>
[ 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 &lt;m202071378@hust.edu.cn&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Link: https://lore.kernel.org/oe-kbuild-all/202304111750.o2643eJN-lkp@intel.com/
Reviewed-by: Dongliang Mu &lt;dzm91@hust.edu.cn&gt;
Link: https://lore.kernel.org/r/20230412033529.18890-1-m202071378@hust.edu.cn
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;m202071378@hust.edu.cn&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Link: https://lore.kernel.org/oe-kbuild-all/202304111750.o2643eJN-lkp@intel.com/
Reviewed-by: Dongliang Mu &lt;dzm91@hust.edu.cn&gt;
Link: https://lore.kernel.org/r/20230412033529.18890-1-m202071378@hust.edu.cn
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: core: Avoid lockdep reports when resolving supplies</title>
<updated>2023-05-11T14:17:06+00:00</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2023-03-29T21:33:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cdc042430ea9e07f77ce05a9d29e227dbdecc733'/>
<id>cdc042430ea9e07f77ce05a9d29e227dbdecc733</id>
<content type='text'>
[ 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)(&amp;entry-&gt;work)){+.+.}-{0:0}, at: process_one_work+0x55c/0x1348
   #2: ffffff80828a2260 (&amp;dev-&gt;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() -&gt; 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 &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.2.I30d8e1ca10cfbe5403884cdd192253a2e063eb9e@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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)(&amp;entry-&gt;work)){+.+.}-{0:0}, at: process_one_work+0x55c/0x1348
   #2: ffffff80828a2260 (&amp;dev-&gt;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() -&gt; 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 &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.2.I30d8e1ca10cfbe5403884cdd192253a2e063eb9e@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: core: Consistently set mutex_owner when using ww_mutex_lock_slow()</title>
<updated>2023-05-11T14:17:06+00:00</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2023-03-29T21:33:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fc0e6b5e46738e74b3616e421b39f3d9d54a3ac9'/>
<id>fc0e6b5e46738e74b3616e421b39f3d9d54a3ac9</id>
<content type='text'>
[ 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 &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.1.I4e9d433ea26360c06dd1381d091c82bb1a4ce843@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ 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 &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230329143317.RFC.v2.1.I4e9d433ea26360c06dd1381d091c82bb1a4ce843@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: core: Shorten off-on-delay-us for always-on/boot-on by time since booted</title>
<updated>2023-05-11T14:16:59+00:00</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2023-03-13T18:18:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=04e8c557cd6a6c9d512a25e7a1d4ba96f46a7d97'/>
<id>04e8c557cd6a6c9d512a25e7a1d4ba96f46a7d97</id>
<content type='text'>
[ Upstream commit 691c1fcda5351ed98a44610b7dccc0e3ee920020 ]

This is very close to a straight revert of commit 218320fec294
("regulator: core: Fix off-on-delay-us for always-on/boot-on
regulators"). We've identified that patch as causing a boot speed
regression on sc7180-trogdor boards. While boot speed certainly isn't
more important than making sure that power sequencing is correct,
looking closely at the original change it doesn't seem to have been
fully justified. It mentions "cycling issues" without describing
exactly what the issues were. That means it's possible that the
cycling issues were really a problem that should be fixed in a
different way.

Let's take a careful look at how we should handle regulators that have
an off-on-delay and that are boot-on or always-on. Linux currently
doesn't have any way to identify whether a GPIO regulator was already
on when the kernel booted. That means that when the kernel boots we
probe a regulator, see that it wants boot-on / always-on we, and then
turn the regulator on. We could be in one of two cases when we do
this:

a) The regulator might have been left on by the bootloader and we're
   ensuring that it stays on.
b) The regulator might have been left off by the bootloader and we're
   just now turning it on.

For case a) we definitely don't need any sort of delay. For case b) we
_might_ need some delay in case the bootloader turned the regulator
off _right_ before booting the kernel. To get the proper delay for
case b) then we can just assume a `last_off` of 0, which is what it
gets initialized to by default.

As per above, we can't tell whether we're in case a) or case b) so
we'll assume the longer delay (case b). This basically puts the code
to how it was before commit 218320fec294 ("regulator: core: Fix
off-on-delay-us for always-on/boot-on regulators"). However, we add
one important change: we make sure that the delay is actually honored
if `last_off` is 0. Though the original "cycling issues" cited were
vague, I'm hopeful that this important extra change will be enough to
fix the issues that the initial commit mentioned.

With this fix, I've confined that on a sc7180-trogdor board the delay
at boot goes down from 500 ms to ~250 ms. That's not as good as the 0
ms that we had prior to commit 218320fec294 ("regulator: core: Fix
off-on-delay-us for always-on/boot-on regulators"), but it's probably
safer because we don't know if the bootloader turned the regulator off
right before booting.

One note is that it's possible that we could be in a state that's not
a) or b) if there are other issues in the kernel. The only one I can
think of is related to pinctrl. If the pinctrl driver being used on a
board isn't careful about avoiding glitches when setting up a pin then
it's possible that setting up a pin could cause the regulator to "turn
off" briefly immediately before the regulator probes. If this is
indeed causing problems then the pinctrl driver should be fixed,
perhaps in a similar way to what was done in commit d21f4b7ffc22
("pinctrl: qcom: Avoid glitching lines when we first mux to output")

Fixes: 218320fec294 ("regulator: core: Fix off-on-delay-us for always-on/boot-on regulators")
Cc: Christian Kohlschütter &lt;christian@kohlschutter.com&gt;
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230313111806.1.I2eaad872be0932a805c239a7c7a102233fb0b03b@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 691c1fcda5351ed98a44610b7dccc0e3ee920020 ]

This is very close to a straight revert of commit 218320fec294
("regulator: core: Fix off-on-delay-us for always-on/boot-on
regulators"). We've identified that patch as causing a boot speed
regression on sc7180-trogdor boards. While boot speed certainly isn't
more important than making sure that power sequencing is correct,
looking closely at the original change it doesn't seem to have been
fully justified. It mentions "cycling issues" without describing
exactly what the issues were. That means it's possible that the
cycling issues were really a problem that should be fixed in a
different way.

Let's take a careful look at how we should handle regulators that have
an off-on-delay and that are boot-on or always-on. Linux currently
doesn't have any way to identify whether a GPIO regulator was already
on when the kernel booted. That means that when the kernel boots we
probe a regulator, see that it wants boot-on / always-on we, and then
turn the regulator on. We could be in one of two cases when we do
this:

a) The regulator might have been left on by the bootloader and we're
   ensuring that it stays on.
b) The regulator might have been left off by the bootloader and we're
   just now turning it on.

For case a) we definitely don't need any sort of delay. For case b) we
_might_ need some delay in case the bootloader turned the regulator
off _right_ before booting the kernel. To get the proper delay for
case b) then we can just assume a `last_off` of 0, which is what it
gets initialized to by default.

As per above, we can't tell whether we're in case a) or case b) so
we'll assume the longer delay (case b). This basically puts the code
to how it was before commit 218320fec294 ("regulator: core: Fix
off-on-delay-us for always-on/boot-on regulators"). However, we add
one important change: we make sure that the delay is actually honored
if `last_off` is 0. Though the original "cycling issues" cited were
vague, I'm hopeful that this important extra change will be enough to
fix the issues that the initial commit mentioned.

With this fix, I've confined that on a sc7180-trogdor board the delay
at boot goes down from 500 ms to ~250 ms. That's not as good as the 0
ms that we had prior to commit 218320fec294 ("regulator: core: Fix
off-on-delay-us for always-on/boot-on regulators"), but it's probably
safer because we don't know if the bootloader turned the regulator off
right before booting.

One note is that it's possible that we could be in a state that's not
a) or b) if there are other issues in the kernel. The only one I can
think of is related to pinctrl. If the pinctrl driver being used on a
board isn't careful about avoiding glitches when setting up a pin then
it's possible that setting up a pin could cause the regulator to "turn
off" briefly immediately before the regulator probes. If this is
indeed causing problems then the pinctrl driver should be fixed,
perhaps in a similar way to what was done in commit d21f4b7ffc22
("pinctrl: qcom: Avoid glitching lines when we first mux to output")

Fixes: 218320fec294 ("regulator: core: Fix off-on-delay-us for always-on/boot-on regulators")
Cc: Christian Kohlschütter &lt;christian@kohlschutter.com&gt;
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Link: https://lore.kernel.org/r/20230313111806.1.I2eaad872be0932a805c239a7c7a102233fb0b03b@changeid
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: sm5703: Fix missing n_voltages for fixed regulators</title>
<updated>2023-04-11T11:41:59+00:00</updated>
<author>
<name>Axel Lin</name>
<email>axel.lin@ingics.com</email>
</author>
<published>2023-04-09T02:55:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c7504067c709905fc188c61ac3072d6022d1209'/>
<id>7c7504067c709905fc188c61ac3072d6022d1209</id>
<content type='text'>
Set n_voltages = 1 for fixed regulators.

Signed-off-by: Axel Lin &lt;axel.lin@ingics.com&gt;
Reviewed-by: Markuss Broks &lt;markuss.broks@gmail.com&gt;
Link: https://lore.kernel.org/r/20230409025529.241699-1-axel.lin@ingics.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Set n_voltages = 1 for fixed regulators.

Signed-off-by: Axel Lin &lt;axel.lin@ingics.com&gt;
Reviewed-by: Markuss Broks &lt;markuss.broks@gmail.com&gt;
Link: https://lore.kernel.org/r/20230409025529.241699-1-axel.lin@ingics.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: fan53555: Fix wrong TCS_SLEW_MASK</title>
<updated>2023-04-06T20:11:24+00:00</updated>
<author>
<name>Cristian Ciocaltea</name>
<email>cristian.ciocaltea@collabora.com</email>
</author>
<published>2023-04-06T17:18:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c5d5b55b3c1a314137a251efc1001dfd435c6242'/>
<id>c5d5b55b3c1a314137a251efc1001dfd435c6242</id>
<content type='text'>
The support for TCS4525 regulator has been introduced with a wrong
ramp-rate mask, which has been defined as a logical expression instead
of a bit shift operation.

For clarity, fix it using GENMASK() macro.

Fixes: 914df8faa7d6 ("regulator: fan53555: Add TCS4525 DCDC support")
Signed-off-by: Cristian Ciocaltea &lt;cristian.ciocaltea@collabora.com&gt;
Link: https://lore.kernel.org/r/20230406171806.948290-4-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The support for TCS4525 regulator has been introduced with a wrong
ramp-rate mask, which has been defined as a logical expression instead
of a bit shift operation.

For clarity, fix it using GENMASK() macro.

Fixes: 914df8faa7d6 ("regulator: fan53555: Add TCS4525 DCDC support")
Signed-off-by: Cristian Ciocaltea &lt;cristian.ciocaltea@collabora.com&gt;
Link: https://lore.kernel.org/r/20230406171806.948290-4-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: fan53555: Explicitly include bits header</title>
<updated>2023-04-06T20:11:23+00:00</updated>
<author>
<name>Cristian Ciocaltea</name>
<email>cristian.ciocaltea@collabora.com</email>
</author>
<published>2023-04-06T17:18:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4fb9a5060f73627303bc531ceaab1b19d0a24aef'/>
<id>4fb9a5060f73627303bc531ceaab1b19d0a24aef</id>
<content type='text'>
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 &lt;cristian.ciocaltea@collabora.com&gt;
Link: https://lore.kernel.org/r/20230406171806.948290-3-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;cristian.ciocaltea@collabora.com&gt;
Link: https://lore.kernel.org/r/20230406171806.948290-3-cristian.ciocaltea@collabora.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: Handle deferred clk</title>
<updated>2023-03-27T00:42:01+00:00</updated>
<author>
<name>Christophe JAILLET</name>
<email>christophe.jaillet@wanadoo.fr</email>
</author>
<published>2023-03-26T08:29:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=02bcba0b9f9da706d5bd1e8cbeb83493863e17b5'/>
<id>02bcba0b9f9da706d5bd1e8cbeb83493863e17b5</id>
<content type='text'>
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 &lt;christophe.jaillet@wanadoo.fr&gt;
Link: https://lore.kernel.org/r/18459fae3d017a66313699c7c8456b28158b2dd0.1679819354.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;christophe.jaillet@wanadoo.fr&gt;
Link: https://lore.kernel.org/r/18459fae3d017a66313699c7c8456b28158b2dd0.1679819354.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
