[PATCH 00/10] -Wunused-const-variable warning fixes

[PATCH 00/10] -Wunused-const-variable warning fixes

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

Most patches I sent during the previous kernel cycle have made it in, these 
ten still remain for the moment. Please apply.

Arnd Bergmann (10):
  drm/imagination: avoid unused-const-variable warning
  [v2] clocksource: atmel_tcb: fix kconfig dependency
  [v2] Input: stmpe-ts - use module alias instead of device table
  [RESEND] mux: adg792a: remove incorrect of_match_ptr annotation
  [RESEND] sched: open-code max_rt_runtime definition
  [RESEND] lockdep: change 'static const' variables to enum values
  [RESEND] ARM: fixmap: make __end_of_early_ioremap_region an enum value
  [RESEND 2] comedi: ni_atmio: avoid warning for unused device_ids[] table
  [RESEND 2] apm-emulation: hide an unused variable
  [RESEND 3] dma/contiguous: avoid warning about unused size_bytes

 arch/arm/include/asm/fixmap.h              |  9 ++++-----
 drivers/char/apm-emulation.c               |  5 ++---
 drivers/clocksource/Kconfig                |  4 ++--
 drivers/comedi/drivers/ni_atmio.c          |  2 +-
 drivers/gpu/drm/imagination/pvr_fw_trace.c |  8 ++++----
 drivers/gpu/drm/imagination/pvr_fw_trace.h |  2 --
 drivers/input/touchscreen/stmpe-ts.c       |  7 +------
 drivers/mux/adg792a.c                      |  2 +-
 kernel/dma/contiguous.c                    |  3 +--
 kernel/locking/lockdep_internals.h         | 18 ++++++++++--------
 kernel/sched/rt.c                          |  6 ++----
 11 files changed, 28 insertions(+), 38 deletions(-)

-- 
2.39.5

Cc: Russell King <linux@armlinux.org.uk> (maintainer:ARM PORT)
Cc: Jiri Kosina <jikos@kernel.org> (maintainer:APM DRIVER)
Cc: Arnd Bergmann <arnd@arndb.de> (maintainer:CHAR and MISC DRIVERS,commit_signer:2/2=100%,authored:2/2=100%,added_lines:8/8=100%,removed_lines:10/10=100%,commit_signer:2/3=67%,authored:2/3=67%,added_lines:2/11=18%,removed_lines:2/2=100%,commit_signer:2/4=50%,blamed_fixes:1/1=100%)
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> (maintainer:CHAR and MISC DRIVERS,commit_signer:1/3=33%)
Cc: Daniel Lezcano <daniel.lezcano@linaro.org> (maintainer:CLOCKSOURCE, CLOCKEVENT DRIVERS)
Cc: Thomas Gleixner <tglx@linutronix.de> (maintainer:CLOCKSOURCE, CLOCKEVENT DRIVERS)
Cc: Ian Abbott <abbotti@mev.co.uk> (maintainer:COMEDI DRIVERS,commit_signer:1/3=33%,authored:1/3=33%,added_lines:9/11=82%)
Cc: H Hartley Sweeten <hsweeten@visionengravers.com> (maintainer:COMEDI DRIVERS)
Cc: Frank Binns <frank.binns@imgtec.com> (maintainer:IMGTEC POWERVR DRM DRIVER)
Cc: Matt Coster <matt.coster@imgtec.com> (maintainer:IMGTEC POWERVR DRM DRIVER)
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> (maintainer:DRM DRIVERS AND MISC GPU PATCHES)
Cc: Maxime Ripard <mripard@kernel.org> (maintainer:DRM DRIVERS AND MISC GPU PATCHES)
Cc: Thomas Zimmermann <tzimmermann@suse.de> (maintainer:DRM DRIVERS AND MISC GPU PATCHES)
Cc: David Airlie <airlied@gmail.com> (maintainer:DRM DRIVERS)
Cc: Simona Vetter <simona@ffwll.ch> (maintainer:DRM DRIVERS)
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> (maintainer:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...,commit_signer:2/4=50%)
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> (maintainer:ARM/STM32 ARCHITECTURE)
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com> (maintainer:ARM/STM32 ARCHITECTURE)
Cc: Peter Rosin <peda@axentia.se> (maintainer:MULTIPLEXER SUBSYSTEM)
Cc: Marek Szyprowski <m.szyprowski@samsung.com> (maintainer:DMA MAPPING HELPERS,blamed_fixes:1/1=100%)
Cc: Robin Murphy <robin.murphy@arm.com> (reviewer:DMA MAPPING HELPERS)
Cc: Peter Zijlstra <peterz@infradead.org> (maintainer:LOCKING PRIMITIVES)
Cc: Ingo Molnar <mingo@redhat.com> (maintainer:LOCKING PRIMITIVES)
Cc: Will Deacon <will@kernel.org> (maintainer:LOCKING PRIMITIVES)
Cc: Boqun Feng <boqun.feng@gmail.com> (maintainer:LOCKING PRIMITIVES)
Cc: Waiman Long <longman@redhat.com> (reviewer:LOCKING PRIMITIVES)
Cc: Juri Lelli <juri.lelli@redhat.com> (maintainer:SCHEDULER)
Cc: Vincent Guittot <vincent.guittot@linaro.org> (maintainer:SCHEDULER)
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> (reviewer:SCHEDULER)
Cc: Steven Rostedt <rostedt@goodmis.org> (reviewer:SCHEDULER)
Cc: Ben Segall <bsegall@google.com> (reviewer:SCHEDULER)
Cc: Mel Gorman <mgorman@suse.de> (reviewer:SCHEDULER)
Cc: Valentin Schneider <vschneid@redhat.com> (reviewer:SCHEDULER)
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> (commit_signer:2/4=50%,authored:2/4=50%,added_lines:2/5=40%,removed_lines:2/5=40%)
Cc: linux-arm-kernel@lists.infradead.org (moderated list:ARM PORT)
Cc: linux-kernel@vger.kernel.org (open list)
Cc: dri-devel@lists.freedesktop.org (open list:DRM DRIVERS)
Cc: linux-input@vger.kernel.org (open list:INPUT (KEYBOARD, MOUSE, JOYSTICK, TOUCHSCREEN)...)
Cc: linux-stm32@st-md-mailman.stormreply.com (moderated list:ARM/STM32 ARCHITECTURE)
Cc: iommu@lists.linux.dev (open list:DMA MAPPING HELPERS)

[PATCH 03/10] [v2] Input: stmpe-ts - use module alias instead of device table

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

When compile tested with W=1 on x86_64 with driver as built-in:

  stmpe-ts.c:371:34: error: unused variable 'stmpe_ts_ids' [-Werror,-Wunused-const-variable]

Ideally this would be referenced from the platform_driver, but since
the compatible string is already matched by the mfd driver for its
parent device, that would break probing.

In this case, the of_device_id table just serves as a module alias
for loading the driver, while the device itself is probed using
the platform device name.

Remove the table and instead use a module alias that reflects how
the driver is actually probed.

Link: https://lore.kernel.org/lkml/20240403080702.3509288-8-arnd@kernel.org/
Link: https://lore.kernel.org/lkml/181dbdb8-c050-4966-8cb4-2f39495ff3f9@app.fastmail.com/
Cc: Uwe Kleine-König" <u.kleine-koenig@baylibre.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v2: use a different approach, hopefully this makes more sense.
---
 drivers/input/touchscreen/stmpe-ts.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/input/touchscreen/stmpe-ts.c b/drivers/input/touchscreen/stmpe-ts.c
index a94a1997f96b..af0fb38bcfdc 100644
--- a/drivers/input/touchscreen/stmpe-ts.c
+++ b/drivers/input/touchscreen/stmpe-ts.c
@@ -366,12 +366,7 @@ static struct platform_driver stmpe_ts_driver = {
 };
 module_platform_driver(stmpe_ts_driver);
 
-static const struct of_device_id stmpe_ts_ids[] = {
-	{ .compatible = "st,stmpe-ts", },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, stmpe_ts_ids);
-
+MODULE_ALIAS("platform:stmpe-ts");
 MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
 MODULE_DESCRIPTION("STMPEXXX touchscreen driver");
 MODULE_LICENSE("GPL");
-- 
2.39.5

Re: [PATCH 03/10] [v2] Input: stmpe-ts - use module alias instead of device table

[Andy Shevchenko]

On Wed, Apr 09, 2025 at 02:22:55PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> When compile tested with W=1 on x86_64 with driver as built-in:
> 
>   stmpe-ts.c:371:34: error: unused variable 'stmpe_ts_ids' [-Werror,-Wunused-const-variable]
> 
> Ideally this would be referenced from the platform_driver, but since
> the compatible string is already matched by the mfd driver for its
> parent device, that would break probing.
> 
> In this case, the of_device_id table just serves as a module alias
> for loading the driver, while the device itself is probed using
> the platform device name.
> 
> Remove the table and instead use a module alias that reflects how
> the driver is actually probed.

...

> +MODULE_ALIAS("platform:stmpe-ts");

Isn't the preferable way to have platform device ID table instead?
Krzysztof?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 03/10] [v2] Input: stmpe-ts - use module alias instead of device table

[Krzysztof Kozlowski]

On 09/04/2025 17:33, Andy Shevchenko wrote:
> On Wed, Apr 09, 2025 at 02:22:55PM +0200, Arnd Bergmann wrote:
>> From: Arnd Bergmann <arnd@arndb.de>
>>
>> When compile tested with W=1 on x86_64 with driver as built-in:
>>
>>   stmpe-ts.c:371:34: error: unused variable 'stmpe_ts_ids' [-Werror,-Wunused-const-variable]
>>
>> Ideally this would be referenced from the platform_driver, but since
>> the compatible string is already matched by the mfd driver for its
>> parent device, that would break probing.
>>
>> In this case, the of_device_id table just serves as a module alias
>> for loading the driver, while the device itself is probed using
>> the platform device name.
>>
>> Remove the table and instead use a module alias that reflects how
>> the driver is actually probed.
> 
> ...
> 
>> +MODULE_ALIAS("platform:stmpe-ts");
> 
> Isn't the preferable way to have platform device ID table instead?
> Krzysztof?

There is no ID table currently and I (usually) object for having both:
ID tables and aliases. In this case it is just simpler to have alias
than entire table and MODULE_DEVICE_TABLE(). Also it is unlikely it will
grow into many aliases. If it tries, then I will object.


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

[PATCH 07/10] [RESEND] ARM: fixmap: make __end_of_early_ioremap_region an enum value

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

Building with W=1 shows warnings for the __end_of_fixed_addresses
definition:

    In file included from mm/early_ioremap.c:18:
    arch/arm/include/asm/fixmap.h:39:35: error: '__end_of_fixed_addresses' defined but not used [-Werror=unused-const-variable=]

Move the calculation slightly up in the file into the enum that
contains __end_of_fixmap_region and __end_of_early_ioremap_region.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/arm/include/asm/fixmap.h | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/arm/include/asm/fixmap.h b/arch/arm/include/asm/fixmap.h
index 707068f852c2..90e0bd79b180 100644
--- a/arch/arm/include/asm/fixmap.h
+++ b/arch/arm/include/asm/fixmap.h
@@ -33,12 +33,11 @@ enum fixed_addresses {
 
 	FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
 	FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
-	__end_of_early_ioremap_region
-};
+	__end_of_early_ioremap_region,
 
-static const enum fixed_addresses __end_of_fixed_addresses =
-	__end_of_fixmap_region > __end_of_early_ioremap_region ?
-	__end_of_fixmap_region : __end_of_early_ioremap_region;
+	__end_of_fixed_addresses = __end_of_fixmap_region > __end_of_early_ioremap_region ?
+				   __end_of_fixmap_region : __end_of_early_ioremap_region,
+};
 
 #define FIXMAP_PAGE_COMMON	(L_PTE_YOUNG | L_PTE_PRESENT | L_PTE_XN | L_PTE_DIRTY)
 
-- 
2.39.5

Re: [PATCH 07/10] [RESEND] ARM: fixmap: make __end_of_early_ioremap_region an enum value

[Andy Shevchenko]

On Wed, Apr 09, 2025 at 02:22:59PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Building with W=1 shows warnings for the __end_of_fixed_addresses
> definition:
> 
>     In file included from mm/early_ioremap.c:18:
>     arch/arm/include/asm/fixmap.h:39:35: error: '__end_of_fixed_addresses' defined but not used [-Werror=unused-const-variable=]
> 
> Move the calculation slightly up in the file into the enum that
> contains __end_of_fixmap_region and __end_of_early_ioremap_region.

...


Maybe format it

> +	__end_of_fixed_addresses = __end_of_fixmap_region > __end_of_early_ioremap_region ?
> +				   __end_of_fixmap_region : __end_of_early_ioremap_region,

as

	__end_of_fixed_addresses =
		__end_of_fixmap_region > __end_of_early_ioremap_region ?
		__end_of_fixmap_region : __end_of_early_ioremap_region,

?

-- 
With Best Regards,
Andy Shevchenko