[PATCH v5 00/18] mfd: demodularization of non-modular drivers

[PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Paul Gortmaker]

[v4 --> v5: add more acks, re-do build tests on newest linux-next after
the 5.0 merge window closed.]

[v3 --> v4: delete now unused exit fcn from wm835x core; add more acks
 now all in chrono order, re-test.]

[v2 --> v3: drop diasemi commits as they will be modularized; delete
 now unused exit fcn from wm831x core; add more acks; re-test.]

[v1 --> v2: add some more commits as requested by Lee (MFD maintainer),
 update the 00/NN text; re-do build and link testing on new linux-next. ]

This group of MFD drivers are all controlled by "bool" Kconfig settings,
but contain various amounts of largely pointless uses of infrastructure
related to modular operations, even though they can't be built modular.

We can easily remove/replace all of it.  We are trying to make driver
code consistent with the Makefiles/Kconfigs that control them.  This
means not using modular functions/macros for drivers that can never be
built as a module.  Some of the downfalls this oversight leads to are:

 (1) it is easy to accidentally write unused module_exit and remove code
 (2) it can be misleading when reading the source, thinking it can be
     modular when the Makefile and/or Kconfig prohibit it
 (3) it requires the include of the module.h header file which in turn
     includes nearly everything else, thus adding a lot of CPP overhead.
 (4) it gets copied/replicated into other drivers and spreads quickly.

What we see in current drivers falls into one or more of the following
categories:

1) include of <linux/module.h> when it simply isn't needed

2) Use of MODULE_LICENSE, MODULE_DEVICE_TABLE,  MODULE_AUTHOR etc. 
   macros that are no-ops for non-modular drivers.

3) Creation of a module_exit() function that will be compiled and
   linked in but never actually called for non-modular drivers.

4) Addition of a platform_driver ".remove" function that is bound
   into the struct but will never be called for non-module use cases.

Solution to #1 --> #3 is simple ; we just delete the related code.

The solution to #4 is similar - we delete the ".remove" function and
the binding into the platform_driver struct.  However, since the same
".remove" function could also be triggered by an "unbind" (such as for
pass-through of a device to a guest instance)  - so we also explicitly
disable any unbind for the driver.

The unbind mask allows us to ensure we will see if there was some odd
corner case out there that was relying on it.  Typically it would be a
multi-port ethernet card passing a port through to a guest, so a
sensible use case in MFD drivers seems highly unlikely.  This same
solution has already been used in multiple other mainline subsystems.

Build testing was done on drivers/mfd for allyesconfig on x86_64, ARM
and ARM-64 on a recent linux-next checkout.

Paul.

---

Cc: Alessandro Rubini <rubini@gnudd.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Cory Maccarrone <darkstar6262@gmail.com>
Cc: Davide Ciminaghi <ciminaghi@gnudd.com>
Cc: Dong Aisheng <dong.aisheng@linaro.org>
Cc: Graeme Gregory <gg@slimlogic.co.uk>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: Jin Park <jinyoungp@nvidia.com>
Cc: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Mattias Nilsson <mattias.i.nilsson@stericsson.com>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Venu Byravarasu <vbyravarasu@nvidia.com>
Cc: linux-omap@vger.kernel.org
Cc: patches@opensource.cirrus.com

Paul Gortmaker (18):
  mfd: aat2870-core: Make it explicitly non-modular
  mfd: adp5520: Make it explicitly non-modular
  mfd: as3711: Make it explicitly non-modular
  mfd: db8500-prcmu: drop unused MODULE_ tags from non-modular code
  mfd: htc-i2cpld: Make it explicitly non-modular
  mfd: max8925-core: drop unused MODULE_ tags from non-modular code
  mfd: rc5t583: Make it explicitly non-modular
  mfd: sta2x11: drop unused MODULE_ tags from non-modular code
  mfd: syscon: Make it explicitly non-modular
  mfd: tps65090: Make it explicitly non-modular
  mfd: tps65910: Make it explicitly non-modular
  mfd: tps80031: Make it explicitly non-modular
  mfd: wm831x-spi: Make it explicitly non-modular
  mfd: wm831x-i2c: Make it explicitly non-modular
  mfd: wm831x-core: drop unused module infrastructure from non-modular code
  mfd: wm8350-i2c: Make it explicitly non-modular
  mfd: wm8350-core: drop unused module infrastructure from non-modular code
  mfd: wm8400-core: Make it explicitly non-modular

 drivers/mfd/aat2870-core.c      | 40 +++-------------------------------------
 drivers/mfd/adp5520.c           | 30 +++++++-----------------------
 drivers/mfd/as3711.c            | 14 --------------
 drivers/mfd/db8500-prcmu.c      | 10 ++++------
 drivers/mfd/htc-i2cpld.c        | 18 +-----------------
 drivers/mfd/max8925-core.c      |  7 +------
 drivers/mfd/rc5t583.c           | 14 --------------
 drivers/mfd/sta2x11-mfd.c       | 10 ++++------
 drivers/mfd/syscon.c            | 12 +-----------
 drivers/mfd/tps65090.c          | 30 +++++-------------------------
 drivers/mfd/tps65910.c          | 18 +-----------------
 drivers/mfd/tps80031.c          | 37 ++-----------------------------------
 drivers/mfd/wm831x-core.c       | 15 ++-------------
 drivers/mfd/wm831x-i2c.c        | 20 ++------------------
 drivers/mfd/wm831x-spi.c        | 24 ++----------------------
 drivers/mfd/wm8350-core.c       | 30 ++----------------------------
 drivers/mfd/wm8350-i2c.c        | 24 +-----------------------
 drivers/mfd/wm8400-core.c       | 18 +++---------------
 include/linux/mfd/wm831x/core.h |  1 -
 include/linux/mfd/wm8350/core.h |  1 -
 20 files changed, 41 insertions(+), 332 deletions(-)

-- 
2.7.4

[PATCH 11/18] mfd: tps65910: Make it explicitly non-modular

[Paul Gortmaker]

The Kconfig currently controlling compilation of this code is:

drivers/mfd/Kconfig:config MFD_TPS65910
drivers/mfd/Kconfig-    bool "TI TPS65910 Power Management chip"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init was not in use by this code, the init ordering
remains unchanged with this commit.

We don't replace module.h with init.h since the file already has that.
We do delete an unused moduleparam.h include though.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Graeme Gregory <gg@slimlogic.co.uk>
Cc: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
Cc: linux-omap@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
---
 drivers/mfd/tps65910.c | 18 +-----------------
 1 file changed, 1 insertion(+), 17 deletions(-)

diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c
index bf16cbe6fd88..aa3d472a10ff 100644
--- a/drivers/mfd/tps65910.c
+++ b/drivers/mfd/tps65910.c
@@ -1,5 +1,5 @@
 /*
- * tps65910.c  --  TI TPS6591x
+ * tps65910.c  --  TI TPS6591x chip family multi-function driver
  *
  * Copyright 2010 Texas Instruments Inc.
  *
@@ -13,8 +13,6 @@
  *
  */
 
-#include <linux/module.h>
-#include <linux/moduleparam.h>
 #include <linux/init.h>
 #include <linux/err.h>
 #include <linux/slab.h>
@@ -374,7 +372,6 @@ static const struct of_device_id tps65910_of_match[] = {
 	{ .compatible = "ti,tps65911", .data = (void *)TPS65911},
 	{ },
 };
-MODULE_DEVICE_TABLE(of, tps65910_of_match);
 
 static struct tps65910_board *tps65910_parse_dt(struct i2c_client *client,
 						unsigned long *chip_id)
@@ -527,8 +524,6 @@ static const struct i2c_device_id tps65910_i2c_id[] = {
        { "tps65911", TPS65911 },
        { }
 };
-MODULE_DEVICE_TABLE(i2c, tps65910_i2c_id);
-
 
 static struct i2c_driver tps65910_i2c_driver = {
 	.driver = {
@@ -545,14 +540,3 @@ static int __init tps65910_i2c_init(void)
 }
 /* init early so consumer devices can complete system boot */
 subsys_initcall(tps65910_i2c_init);
-
-static void __exit tps65910_i2c_exit(void)
-{
-	i2c_del_driver(&tps65910_i2c_driver);
-}
-module_exit(tps65910_i2c_exit);
-
-MODULE_AUTHOR("Graeme Gregory <gg@slimlogic.co.uk>");
-MODULE_AUTHOR("Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>");
-MODULE_DESCRIPTION("TPS6591x chip family multi-function driver");
-MODULE_LICENSE("GPL");
-- 
2.7.4

Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Lee Jones]

[...]

> Paul Gortmaker (18):
>   mfd: aat2870-core: Make it explicitly non-modular
>   mfd: adp5520: Make it explicitly non-modular
>   mfd: as3711: Make it explicitly non-modular
>   mfd: db8500-prcmu: drop unused MODULE_ tags from non-modular code
>   mfd: htc-i2cpld: Make it explicitly non-modular
>   mfd: max8925-core: drop unused MODULE_ tags from non-modular code
>   mfd: rc5t583: Make it explicitly non-modular
>   mfd: sta2x11: drop unused MODULE_ tags from non-modular code
>   mfd: syscon: Make it explicitly non-modular
>   mfd: tps65090: Make it explicitly non-modular
>   mfd: tps65910: Make it explicitly non-modular
>   mfd: tps80031: Make it explicitly non-modular
>   mfd: wm831x-spi: Make it explicitly non-modular
>   mfd: wm831x-i2c: Make it explicitly non-modular
>   mfd: wm831x-core: drop unused module infrastructure from non-modular code
>   mfd: wm8350-i2c: Make it explicitly non-modular
>   mfd: wm8350-core: drop unused module infrastructure from non-modular code
>   mfd: wm8400-core: Make it explicitly non-modular
> 
>  drivers/mfd/aat2870-core.c      | 40 +++-------------------------------------
>  drivers/mfd/adp5520.c           | 30 +++++++-----------------------
>  drivers/mfd/as3711.c            | 14 --------------
>  drivers/mfd/db8500-prcmu.c      | 10 ++++------
>  drivers/mfd/htc-i2cpld.c        | 18 +-----------------
>  drivers/mfd/max8925-core.c      |  7 +------
>  drivers/mfd/rc5t583.c           | 14 --------------
>  drivers/mfd/sta2x11-mfd.c       | 10 ++++------
>  drivers/mfd/syscon.c            | 12 +-----------
>  drivers/mfd/tps65090.c          | 30 +++++-------------------------
>  drivers/mfd/tps65910.c          | 18 +-----------------
>  drivers/mfd/tps80031.c          | 37 ++-----------------------------------
>  drivers/mfd/wm831x-core.c       | 15 ++-------------
>  drivers/mfd/wm831x-i2c.c        | 20 ++------------------
>  drivers/mfd/wm831x-spi.c        | 24 ++----------------------
>  drivers/mfd/wm8350-core.c       | 30 ++----------------------------
>  drivers/mfd/wm8350-i2c.c        | 24 +-----------------------
>  drivers/mfd/wm8400-core.c       | 18 +++---------------
>  include/linux/mfd/wm831x/core.h |  1 -
>  include/linux/mfd/wm8350/core.h |  1 -
>  20 files changed, 41 insertions(+), 332 deletions(-)

All applied!

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 1855 bytes --]

On Wed 2019-01-16 13:24:31, Lee Jones wrote:
> [...]
> 
> > Paul Gortmaker (18):
> >   mfd: aat2870-core: Make it explicitly non-modular
> >   mfd: adp5520: Make it explicitly non-modular
> >   mfd: as3711: Make it explicitly non-modular
> >   mfd: db8500-prcmu: drop unused MODULE_ tags from non-modular code
> >   mfd: htc-i2cpld: Make it explicitly non-modular
> >   mfd: max8925-core: drop unused MODULE_ tags from non-modular code
> >   mfd: rc5t583: Make it explicitly non-modular
> >   mfd: sta2x11: drop unused MODULE_ tags from non-modular code
> >   mfd: syscon: Make it explicitly non-modular
> >   mfd: tps65090: Make it explicitly non-modular
> >   mfd: tps65910: Make it explicitly non-modular
> >   mfd: tps80031: Make it explicitly non-modular
> >   mfd: wm831x-spi: Make it explicitly non-modular
> >   mfd: wm831x-i2c: Make it explicitly non-modular
> >   mfd: wm831x-core: drop unused module infrastructure from non-modular code
> >   mfd: wm8350-i2c: Make it explicitly non-modular
> >   mfd: wm8350-core: drop unused module infrastructure from non-modular code
> >   mfd: wm8400-core: Make it explicitly non-modular
> > 
> >  drivers/mfd/aat2870-core.c      | 40 +++-------------------------------------
> >  drivers/mfd/adp5520.c           | 30 +++++++-----------------------
> >  drivers/mfd/as3711.c            | 14 --------------
> >  drivers/mfd/db8500-prcmu.c      | 10 ++++------
> >  drivers/mfd/htc-i2cpld.c        | 18 +-----------------
> >  20 files changed, 41 insertions(+), 332 deletions(-)
> 
> All applied!

Is it good idea?

We want distro kernels on ARM, too, which means people will eventually
want these as a modules, no?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Paul Gortmaker]

[Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers] On 07/03/2019 (Thu 00:10) Pavel Machek wrote:

> On Wed 2019-01-16 13:24:31, Lee Jones wrote:
> > [...]
> > 
> > > Paul Gortmaker (18):
> > >   mfd: aat2870-core: Make it explicitly non-modular
> > >   mfd: adp5520: Make it explicitly non-modular
> > >   mfd: as3711: Make it explicitly non-modular
> > >   mfd: db8500-prcmu: drop unused MODULE_ tags from non-modular code
> > >   mfd: htc-i2cpld: Make it explicitly non-modular
> > >   mfd: max8925-core: drop unused MODULE_ tags from non-modular code
> > >   mfd: rc5t583: Make it explicitly non-modular
> > >   mfd: sta2x11: drop unused MODULE_ tags from non-modular code
> > >   mfd: syscon: Make it explicitly non-modular
> > >   mfd: tps65090: Make it explicitly non-modular
> > >   mfd: tps65910: Make it explicitly non-modular
> > >   mfd: tps80031: Make it explicitly non-modular
> > >   mfd: wm831x-spi: Make it explicitly non-modular
> > >   mfd: wm831x-i2c: Make it explicitly non-modular
> > >   mfd: wm831x-core: drop unused module infrastructure from non-modular code
> > >   mfd: wm8350-i2c: Make it explicitly non-modular
> > >   mfd: wm8350-core: drop unused module infrastructure from non-modular code
> > >   mfd: wm8400-core: Make it explicitly non-modular
> > > 
> > >  drivers/mfd/aat2870-core.c      | 40 +++-------------------------------------
> > >  drivers/mfd/adp5520.c           | 30 +++++++-----------------------
> > >  drivers/mfd/as3711.c            | 14 --------------
> > >  drivers/mfd/db8500-prcmu.c      | 10 ++++------
> > >  drivers/mfd/htc-i2cpld.c        | 18 +-----------------
> > >  20 files changed, 41 insertions(+), 332 deletions(-)
> > 
> > All applied!
> 
> Is it good idea?

Pavel, I think yes it is good, and I hope you will allow me the chance
to convince you of the same.  It removes dead code, and removes the
chance that people mistakenly believe any of these drivers were
currently possible as modules, when they were really NOT at all modular.

> We want distro kernels on ARM, too, which means people will eventually
> want these as a modules, no?

And at the risk of repeating something I've said a lot already, this
is fine, and I 100% support people converting drivers to being modular,
in the case where there is demand, and where people with the hardware
who are willing to test that the modular use-case actually works.

If people want it to be modular, then this work actually helps.  You
don't have drivers "hiding in the shadows" that pretend to be modules.
Such drivers do not at all help with the "distro kernels" use case.

If a driver author responds and says they intended to make their driver
a module, I 100% support them, and will drop the code removal patch and
also have supported them in making their work tristate.  If the choice
to convert to tristate happens a year or more from now, it is trivial to
reclaim the unused-but-deleted code from git.

But, again as I have said many times -- I can't know every detail of
each driver to know if module/tristate makes any sense, as a use-case or
if even technically possible (such as in DMA/IOMMU or similar low level
core systems).   So the right option is to remove the dead code and not
impact the existing driver behaviour, and make it clear in the process
to the authors and users, that the driver was never modular to begin
with --  and in doing so, give them all a chance to comment and react.

Pavel, I hope this more extended explanation makes sense to you, and
that you simply have not seen me write these same details in the past.

Thanks,
Paul.
--

> 									Pavel
> -- 
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Lee Jones]

On Wed, 06 Mar 2019, Paul Gortmaker wrote:

> [Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers] On 07/03/2019 (Thu 00:10) Pavel Machek wrote:
> 
> > On Wed 2019-01-16 13:24:31, Lee Jones wrote:
> > > [...]
> > > 
> > > > Paul Gortmaker (18):
> > > >   mfd: aat2870-core: Make it explicitly non-modular
> > > >   mfd: adp5520: Make it explicitly non-modular
> > > >   mfd: as3711: Make it explicitly non-modular
> > > >   mfd: db8500-prcmu: drop unused MODULE_ tags from non-modular code
> > > >   mfd: htc-i2cpld: Make it explicitly non-modular
> > > >   mfd: max8925-core: drop unused MODULE_ tags from non-modular code
> > > >   mfd: rc5t583: Make it explicitly non-modular
> > > >   mfd: sta2x11: drop unused MODULE_ tags from non-modular code
> > > >   mfd: syscon: Make it explicitly non-modular
> > > >   mfd: tps65090: Make it explicitly non-modular
> > > >   mfd: tps65910: Make it explicitly non-modular
> > > >   mfd: tps80031: Make it explicitly non-modular
> > > >   mfd: wm831x-spi: Make it explicitly non-modular
> > > >   mfd: wm831x-i2c: Make it explicitly non-modular
> > > >   mfd: wm831x-core: drop unused module infrastructure from non-modular code
> > > >   mfd: wm8350-i2c: Make it explicitly non-modular
> > > >   mfd: wm8350-core: drop unused module infrastructure from non-modular code
> > > >   mfd: wm8400-core: Make it explicitly non-modular
> > > > 
> > > >  drivers/mfd/aat2870-core.c      | 40 +++-------------------------------------
> > > >  drivers/mfd/adp5520.c           | 30 +++++++-----------------------
> > > >  drivers/mfd/as3711.c            | 14 --------------
> > > >  drivers/mfd/db8500-prcmu.c      | 10 ++++------
> > > >  drivers/mfd/htc-i2cpld.c        | 18 +-----------------
> > > >  20 files changed, 41 insertions(+), 332 deletions(-)
> > > 
> > > All applied!
> > 
> > Is it good idea?
> 
> Pavel, I think yes it is good, and I hope you will allow me the chance
> to convince you of the same.  It removes dead code, and removes the
> chance that people mistakenly believe any of these drivers were
> currently possible as modules, when they were really NOT at all modular.
> 
> > We want distro kernels on ARM, too, which means people will eventually
> > want these as a modules, no?
> 
> And at the risk of repeating something I've said a lot already, this
> is fine, and I 100% support people converting drivers to being modular,
> in the case where there is demand, and where people with the hardware
> who are willing to test that the modular use-case actually works.
> 
> If people want it to be modular, then this work actually helps.  You
> don't have drivers "hiding in the shadows" that pretend to be modules.
> Such drivers do not at all help with the "distro kernels" use case.
> 
> If a driver author responds and says they intended to make their driver
> a module, I 100% support them, and will drop the code removal patch and
> also have supported them in making their work tristate.  If the choice
> to convert to tristate happens a year or more from now, it is trivial to
> reclaim the unused-but-deleted code from git.
> 
> But, again as I have said many times -- I can't know every detail of
> each driver to know if module/tristate makes any sense, as a use-case or
> if even technically possible (such as in DMA/IOMMU or similar low level
> core systems).   So the right option is to remove the dead code and not
> impact the existing driver behaviour, and make it clear in the process
> to the authors and users, that the driver was never modular to begin
> with --  and in doing so, give them all a chance to comment and react.
> 
> Pavel, I hope this more extended explanation makes sense to you, and
> that you simply have not seen me write these same details in the past.

Blimey.  That's a really long winded way of saying:

  "Modular-ness is actually broken in these drivers; [Paul]'s patches
   make that point clear for all to see.  If people (authors/distros)
   wish them to be modular, they need to fix them properly."

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 706 bytes --]


> > Pavel, I hope this more extended explanation makes sense to you, and
> > that you simply have not seen me write these same details in the past.
> 
> Blimey.  That's a really long winded way of saying:
> 
>   "Modular-ness is actually broken in these drivers; [Paul]'s patches
>    make that point clear for all to see.  If people (authors/distros)
>    wish them to be modular, they need to fix them properly."

Has that been checked?

I mean... when I saw the patch I thought "perhaps it should be doing
bool->tristate instead"?

									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: [PATCH v5 00/18] mfd: demodularization of non-modular drivers

[Tony Lindgren]

* Pavel Machek <pavel@ucw.cz> [190307 08:35]:
> 
> > > Pavel, I hope this more extended explanation makes sense to you, and
> > > that you simply have not seen me write these same details in the past.
> > 
> > Blimey.  That's a really long winded way of saying:
> > 
> >   "Modular-ness is actually broken in these drivers; [Paul]'s patches
> >    make that point clear for all to see.  If people (authors/distros)
> >    wish them to be modular, they need to fix them properly."
> 
> Has that been checked?
> 
> I mean... when I saw the patch I thought "perhaps it should be doing
> bool->tristate instead"?

Thinking distors and loadable modules,  for PMICs, only regulators need
to be built-in in most cases. That's at least the case for example with
drivers/mfd/motorola-cpcap.c.

I'd say applying these patches makes sense unless we have people
step up and fix their drivers.

Regards,

Tony