Re: linux-next: manual merge of the backlight tree with the drm-misc tree

[Neil Armstrong <neil.armstrong@linaro.org>]

On 10/30/25 09:14, Thomas Zimmermann wrote:
> Hi
> 
> Am 30.10.25 um 05:14 schrieb Stephen Rothwell:
>> Hi all,
>>
>> After merging the backlight tree, today's linux-next build (x86_64
>> allmodconfig) failed like this:
>>
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:41:41: error: array type has incomplete element type 'struct regulator_bulk_data'
>>     41 | static const struct regulator_bulk_data tddi_supplies[] = {
>>        |                                         ^~~~~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c: In function 'tddi_prepare':
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:72:15: error: implicit declaration of function 'regulator_bulk_enable' [-Wimplicit-function-declaration]
>>     72 |         ret = regulator_bulk_enable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
>>        |               ^~~~~~~~~~~~~~~~~~~~~
>> In file included from include/linux/dev_printk.h:14,
>>                   from include/linux/device.h:15,
>>                   from include/linux/backlight.h:12,
>>                   from drivers/gpu/drm/panel/panel-synaptics-tddi.c:8:
>> include/linux/compiler.h:201:82: error: expression in static assertion is not an integer
>>    201 | #define __BUILD_BUG_ON_ZERO_MSG(e, msg, ...) ((int)sizeof(struct {_Static_assert(!(e), msg);}))
>>        |                                                                                  ^
>> include/linux/compiler.h:206:33: note: in expansion of macro '__BUILD_BUG_ON_ZERO_MSG'
>>    206 | #define __must_be_array(a)      __BUILD_BUG_ON_ZERO_MSG(!__is_array(a), \
>>        |                                 ^~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array'
>>     11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
>>        |                                                           ^~~~~~~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:72:37: note: in expansion of macro 'ARRAY_SIZE'
>>     72 |         ret = regulator_bulk_enable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
>>        |                                     ^~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c: In function 'tddi_unprepare':
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:101:9: error: implicit declaration of function 'regulator_bulk_disable' [-Wimplicit-function-declaration]
>>    101 |         regulator_bulk_disable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
>>        |         ^~~~~~~~~~~~~~~~~~~~~~
>> include/linux/compiler.h:201:82: error: expression in static assertion is not an integer
>>    201 | #define __BUILD_BUG_ON_ZERO_MSG(e, msg, ...) ((int)sizeof(struct {_Static_assert(!(e), msg);}))
>>        |                                                                                  ^
>> include/linux/compiler.h:206:33: note: in expansion of macro '__BUILD_BUG_ON_ZERO_MSG'
>>    206 | #define __must_be_array(a)      __BUILD_BUG_ON_ZERO_MSG(!__is_array(a), \
>>        |                                 ^~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array'
>>     11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
>>        |                                                           ^~~~~~~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:101:32: note: in expansion of macro 'ARRAY_SIZE'
>>    101 |         regulator_bulk_disable(ARRAY_SIZE(tddi_supplies), ctx->supplies);
>>        |                                ^~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c: In function 'tddi_probe':
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:183:15: error: implicit declaration of function 'devm_regulator_bulk_get_const' [-Wimplicit-function-declaration]
>>    183 |         ret = devm_regulator_bulk_get_const(dev, ARRAY_SIZE(tddi_supplies),
>>        |               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/compiler.h:201:82: error: expression in static assertion is not an integer
>>    201 | #define __BUILD_BUG_ON_ZERO_MSG(e, msg, ...) ((int)sizeof(struct {_Static_assert(!(e), msg);}))
>>        |                                                                                  ^
>> include/linux/compiler.h:206:33: note: in expansion of macro '__BUILD_BUG_ON_ZERO_MSG'
>>    206 | #define __must_be_array(a)      __BUILD_BUG_ON_ZERO_MSG(!__is_array(a), \
>>        |                                 ^~~~~~~~~~~~~~~~~~~~~~~
>> include/linux/array_size.h:11:59: note: in expansion of macro '__must_be_array'
>>     11 | #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
>>        |                                                           ^~~~~~~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:183:50: note: in expansion of macro 'ARRAY_SIZE'
>>    183 |         ret = devm_regulator_bulk_get_const(dev, ARRAY_SIZE(tddi_supplies),
>>        |                                                  ^~~~~~~~~~
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c: At top level:
>> drivers/gpu/drm/panel/panel-synaptics-tddi.c:41:41: error: 'tddi_supplies' defined but not used [-Werror=unused-variable]
>>     41 | static const struct regulator_bulk_data tddi_supplies[] = {
>>        |                                         ^~~~~~~~~~~~~
>> cc1: all warnings being treated as errors
>>
>> Caused by commit
>>
>>    243ce64b2b37 ("backlight: Do not include <linux/fb.h> in header file")
>>
>> interacting with commit
>>
>>    3eae82503f4f ("drm: panel: add support for Synaptics TDDI series DSI panels")
>>
>> from the drm-misc tree.
>>
>> I have applied the following merge fix patch.  It (or something linke it)
>> should be applied to the drm-misc tree.
>>
>> From: Stephen Rothwell <sfr@canb.auug.org.au>
>> Date: Thu, 30 Oct 2025 14:57:03 +1100
>> Subject: [PATCH] fix up for "backlight: Do not include <linux/fb.h> in header file"
>>
>> interacting with commit
>>
>>    3eae82503f4f ("drm: panel: add support for Synaptics TDDI series DSI panels")
>>
>> from the drm-misc tree.
>>
>> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
> 
> Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
> 
> I think we can take your patch into drm-misc. Thanks for fixing this.

I'm preparing the patch right now.

Thanks,
Neil

> 
> Best regards
> Thomas
> 
>> ---
>>   drivers/gpu/drm/panel/panel-synaptics-tddi.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/gpu/drm/panel/panel-synaptics-tddi.c b/drivers/gpu/drm/panel/panel-synaptics-tddi.c
>> index a4b3cbdebb6c..0aea1854710e 100644
>> --- a/drivers/gpu/drm/panel/panel-synaptics-tddi.c
>> +++ b/drivers/gpu/drm/panel/panel-synaptics-tddi.c
>> @@ -9,6 +9,7 @@
>>   #include <linux/gpio/consumer.h>
>>   #include <linux/module.h>
>>   #include <linux/of.h>
>> +#include <linux/regulator/consumer.h>
>>   #include <video/mipi_display.h>
>