[PATCH 0/2] mcb: Add modpost support for processing MODULE_DEVICE_TABLE

[PATCH 0/2] mcb: Add modpost support for processing MODULE_DEVICE_TABLE

[Jose Javier Rodriguez Barbarin]

During the process of update of one of the device drivers that are part of
mcb bus (gpio-menz127.c), one maintainer of the GPIO subsystem asked me
why I was adding new MODULE_ALIAS when I also added the same new
information on MODULE_DEVICE_TABLE.

You can find the messages here:

https://lore.kernel.org/linux-gpio/80a20b13-7c6a-4483-9741-568424f957ef@kernel.org/

After a deeper analysis, I came across that the mcb_table_id defined inside
MODULE_DEVICE_TABLE on all device drivers was being ignored as modpost was
not processing the mcb MODULE_DEVICE_TABLE entries. For this reason, former
contributors were using MODULE_ALIAS for enabling mcb to autoload the
device drivers.

My proposal with these changes is to complete the mcb bus by adding
modpost support for processing mcb MODULE_DEVICE_TABLE and removing
MODULE_ALIAS from all device drivers as they are no longer needed.

Jose Javier Rodriguez Barbarin (2):
  mcb: Add missing modpost build support
  mcb: Remove MODULE_ALIAS from all mcb client drivers

 drivers/gpio/gpio-menz127.c            | 1 -
 drivers/iio/adc/men_z188_adc.c         | 1 -
 drivers/tty/serial/8250/8250_men_mcb.c | 3 ---
 drivers/tty/serial/men_z135_uart.c     | 1 -
 drivers/watchdog/menz69_wdt.c          | 1 -
 scripts/mod/devicetable-offsets.c      | 3 +++
 scripts/mod/file2alias.c               | 9 +++++++++
 7 files changed, 12 insertions(+), 7 deletions(-)

-- 
2.51.1

[PATCH 1/2] mcb: Add missing modpost build support

[Jose Javier Rodriguez Barbarin]

mcb bus is not prepared to autoload client drivers with the data defined on
the drivers' MODULE_DEVICE_TABLE. modpost cannot access to mcb_table_id
inside MODULE_DEVICE_TABLE so the data declared inside is ignored.

Add modpost build support for accessing to the mcb_table_id coded on device
drivers' MODULE_DEVICE_TABLE.

Reviewed-by: Jorge Sanjuan Garcia <dev-jorge.sanjuangarcia@duagon.com>
Signed-off-by: Jose Javier Rodriguez Barbarin <dev-josejavier.rodriguez@duagon.com>
---
 scripts/mod/devicetable-offsets.c | 3 +++
 scripts/mod/file2alias.c          | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index d3d00e85edf7..8e89d07a9337 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -209,6 +209,9 @@ int main(void)
 	DEVID_FIELD(rio_device_id, asm_did);
 	DEVID_FIELD(rio_device_id, asm_vid);
 
+	DEVID(mcb_device_id);
+	DEVID_FIELD(mcb_device_id, device);
+
 	DEVID(ulpi_device_id);
 	DEVID_FIELD(ulpi_device_id, vendor);
 	DEVID_FIELD(ulpi_device_id, product);
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index b3333560b95e..f02dfc186730 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1144,6 +1144,14 @@ static void do_rio_entry(struct module *mod, void *symval)
 	module_alias_printf(mod, true, "rapidio:%s", alias);
 }
 
+/* Looks like: mcb:16zN */
+static void do_mcb_entry(struct module *mod, void *symval)
+{
+	DEF_FIELD(symval, mcb_device_id, device);
+
+	module_alias_printf(mod, false, "mcb:16z%03d", device);
+}
+
 /* Looks like: ulpi:vNpN */
 static void do_ulpi_entry(struct module *mod, void *symval)
 {
@@ -1446,6 +1454,7 @@ static const struct devtable devtable[] = {
 	{"cpu", SIZE_cpu_feature, do_cpu_entry},
 	{"mei", SIZE_mei_cl_device_id, do_mei_entry},
 	{"rapidio", SIZE_rio_device_id, do_rio_entry},
+	{"mcb", SIZE_mcb_device_id, do_mcb_entry},
 	{"ulpi", SIZE_ulpi_device_id, do_ulpi_entry},
 	{"hdaudio", SIZE_hda_device_id, do_hda_entry},
 	{"sdw", SIZE_sdw_device_id, do_sdw_entry},
-- 
2.51.1

[PATCH 2/2] mcb: Remove MODULE_ALIAS from all mcb client drivers

[Jose Javier Rodriguez Barbarin]

MODULE_ALIAS information is no longer needed as now all mcb client
drivers are reporting such information through MODULE_DEVICE_TABLE.

Reviewed-by: Jorge Sanjuan Garcia <dev-jorge.sanjuangarcia@duagon.com>
Signed-off-by: Jose Javier Rodriguez Barbarin <dev-josejavier.rodriguez@duagon.com>
---
 drivers/gpio/gpio-menz127.c            | 1 -
 drivers/iio/adc/men_z188_adc.c         | 1 -
 drivers/tty/serial/8250/8250_men_mcb.c | 3 ---
 drivers/tty/serial/men_z135_uart.c     | 1 -
 drivers/watchdog/menz69_wdt.c          | 1 -
 5 files changed, 7 deletions(-)

diff --git a/drivers/gpio/gpio-menz127.c b/drivers/gpio/gpio-menz127.c
index 52b13c6ae496..f51e7517f551 100644
--- a/drivers/gpio/gpio-menz127.c
+++ b/drivers/gpio/gpio-menz127.c
@@ -223,5 +223,4 @@ module_mcb_driver(men_z127_driver);
 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
 MODULE_DESCRIPTION("MEN GPIO Controller");
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("mcb:16z127");
 MODULE_IMPORT_NS("MCB");
diff --git a/drivers/iio/adc/men_z188_adc.c b/drivers/iio/adc/men_z188_adc.c
index cf8a8c0412ec..90919d282e7b 100644
--- a/drivers/iio/adc/men_z188_adc.c
+++ b/drivers/iio/adc/men_z188_adc.c
@@ -171,5 +171,4 @@ module_mcb_driver(men_z188_driver);
 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core");
-MODULE_ALIAS("mcb:16z188");
 MODULE_IMPORT_NS("MCB");
diff --git a/drivers/tty/serial/8250/8250_men_mcb.c b/drivers/tty/serial/8250/8250_men_mcb.c
index a78ef35c8187..9774a95f2980 100644
--- a/drivers/tty/serial/8250/8250_men_mcb.c
+++ b/drivers/tty/serial/8250/8250_men_mcb.c
@@ -268,7 +268,4 @@ module_mcb_driver(mcb_driver);
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("MEN 8250 UART driver");
 MODULE_AUTHOR("Michael Moese <michael.moese@men.de");
-MODULE_ALIAS("mcb:16z125");
-MODULE_ALIAS("mcb:16z025");
-MODULE_ALIAS("mcb:16z057");
 MODULE_IMPORT_NS("MCB");
diff --git a/drivers/tty/serial/men_z135_uart.c b/drivers/tty/serial/men_z135_uart.c
index 9cc15449b673..6fad57fee912 100644
--- a/drivers/tty/serial/men_z135_uart.c
+++ b/drivers/tty/serial/men_z135_uart.c
@@ -919,5 +919,4 @@ module_exit(men_z135_exit);
 MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>");
 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("MEN 16z135 High Speed UART");
-MODULE_ALIAS("mcb:16z135");
 MODULE_IMPORT_NS("MCB");
diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c
index 6e5e4e5c0b56..3fe23451135d 100644
--- a/drivers/watchdog/menz69_wdt.c
+++ b/drivers/watchdog/menz69_wdt.c
@@ -163,5 +163,4 @@ module_mcb_driver(men_z069_driver);
 MODULE_AUTHOR("Johannes Thumshirn <jth@kernel.org>");
 MODULE_DESCRIPTION("Watchdog driver for the MEN z069 IP-Core");
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("mcb:16z069");
 MODULE_IMPORT_NS("MCB");
-- 
2.51.1

Re: [PATCH 1/2] mcb: Add missing modpost build support

[Andy Shevchenko]

On Thu, Nov 27, 2025 at 5:56 PM Jose Javier Rodriguez Barbarin
<dev-josejavier.rodriguez@duagon.com> wrote:
>
> mcb bus is not prepared to autoload client drivers with the data defined on
> the drivers' MODULE_DEVICE_TABLE. modpost cannot access to mcb_table_id
> inside MODULE_DEVICE_TABLE so the data declared inside is ignored.
>
> Add modpost build support for accessing to the mcb_table_id coded on device
> drivers' MODULE_DEVICE_TABLE.

...

>  static const struct devtable devtable[] = {

>         {"cpu", SIZE_cpu_feature, do_cpu_entry},
>         {"mei", SIZE_mei_cl_device_id, do_mei_entry},
>         {"rapidio", SIZE_rio_device_id, do_rio_entry},
> +       {"mcb", SIZE_mcb_device_id, do_mcb_entry},

Perhaps squeeze it to be more ordered (yes, I know that the table is
not so ordered, but given context suggests to put it after "mei").

>         {"ulpi", SIZE_ulpi_device_id, do_ulpi_entry},
>         {"hdaudio", SIZE_hda_device_id, do_hda_entry},
>         {"sdw", SIZE_sdw_device_id, do_sdw_entry},



-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 2/2] mcb: Remove MODULE_ALIAS from all mcb client drivers

[Andy Shevchenko]

On Thu, Nov 27, 2025 at 5:56 PM Jose Javier Rodriguez Barbarin
<dev-josejavier.rodriguez@duagon.com> wrote:
>
> MODULE_ALIAS information is no longer needed as now all mcb client
> drivers are reporting such information through MODULE_DEVICE_TABLE.

While this is not a big change, I still would recommend to split on
per-driver basis, and with pushing the first one as kinda a fix after
v6.19-rc1 (to v6.19-rcX) allows other maintainers to apply the rest on
driver-basis. This helps everybody I assume.


-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 0/2] mcb: Add modpost support for processing MODULE_DEVICE_TABLE

[Andy Shevchenko]

On Thu, Nov 27, 2025 at 5:56 PM Jose Javier Rodriguez Barbarin
<dev-josejavier.rodriguez@duagon.com> wrote:
>
> During the process of update of one of the device drivers that are part of
> mcb bus (gpio-menz127.c),

> one maintainer of the GPIO subsystem

Krzysztof? Did I miss something and he is now a (co)maintainer here?

> asked me
> why I was adding new MODULE_ALIAS when I also added the same new
> information on MODULE_DEVICE_TABLE.
>
> You can find the messages here:
>
> https://lore.kernel.org/linux-gpio/80a20b13-7c6a-4483-9741-568424f957ef@kernel.org/
>
> After a deeper analysis, I came across that the mcb_table_id defined inside
> MODULE_DEVICE_TABLE on all device drivers was being ignored as modpost was
> not processing the mcb MODULE_DEVICE_TABLE entries. For this reason, former
> contributors were using MODULE_ALIAS for enabling mcb to autoload the
> device drivers.
>
> My proposal with these changes is to complete the mcb bus by adding
> modpost support for processing mcb MODULE_DEVICE_TABLE and removing
> MODULE_ALIAS from all device drivers as they are no longer needed.
>
> Jose Javier Rodriguez Barbarin (2):
>   mcb: Add missing modpost build support
>   mcb: Remove MODULE_ALIAS from all mcb client drivers
>
>  drivers/gpio/gpio-menz127.c            | 1 -
>  drivers/iio/adc/men_z188_adc.c         | 1 -
>  drivers/tty/serial/8250/8250_men_mcb.c | 3 ---
>  drivers/tty/serial/men_z135_uart.c     | 1 -
>  drivers/watchdog/menz69_wdt.c          | 1 -
>  scripts/mod/devicetable-offsets.c      | 3 +++
>  scripts/mod/file2alias.c               | 9 +++++++++
>  7 files changed, 12 insertions(+), 7 deletions(-)
>
> --
> 2.51.1



-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 1/2] mcb: Add missing modpost build support

[Jiri Slaby]

On 27. 11. 25, 17:10, Andy Shevchenko wrote:
>>   static const struct devtable devtable[] = {
> 
>>          {"cpu", SIZE_cpu_feature, do_cpu_entry},
>>          {"mei", SIZE_mei_cl_device_id, do_mei_entry},
>>          {"rapidio", SIZE_rio_device_id, do_rio_entry},
>> +       {"mcb", SIZE_mcb_device_id, do_mcb_entry},
> 
> Perhaps squeeze it to be more ordered (yes, I know that the table is
> not so ordered, but given context suggests to put it after "mei").

s/after/before/ :)

-- 
js
suse labs

Re: [PATCH 1/2] mcb: Add missing modpost build support

[Andy Shevchenko]

On Fri, Nov 28, 2025 at 08:54:18AM +0100, Jiri Slaby wrote:
> On 27. 11. 25, 17:10, Andy Shevchenko wrote:

...

> > >   static const struct devtable devtable[] = {
> > 
> > >          {"cpu", SIZE_cpu_feature, do_cpu_entry},
> > >          {"mei", SIZE_mei_cl_device_id, do_mei_entry},
> > >          {"rapidio", SIZE_rio_device_id, do_rio_entry},
> > > +       {"mcb", SIZE_mcb_device_id, do_mcb_entry},
> > 
> > Perhaps squeeze it to be more ordered (yes, I know that the table is
> > not so ordered, but given context suggests to put it after "mei").
> 
> s/after/before/ :)

Right, good catch!

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 1/2] mcb: Add missing modpost build support

[Jose Javier Rodriguez Barbarin]

On Fri, Nov 28, 2025 at 11:02:57AM +0200, Andy Shevchenko wrote:
> On Fri, Nov 28, 2025 at 08:54:18AM +0100, Jiri Slaby wrote:
> > On 27. 11. 25, 17:10, Andy Shevchenko wrote:
> 
> ...
> 
> > > >   static const struct devtable devtable[] = {
> > > 
> > > >          {"cpu", SIZE_cpu_feature, do_cpu_entry},
> > > >          {"mei", SIZE_mei_cl_device_id, do_mei_entry},
> > > >          {"rapidio", SIZE_rio_device_id, do_rio_entry},
> > > > +       {"mcb", SIZE_mcb_device_id, do_mcb_entry},
> > > 
> > > Perhaps squeeze it to be more ordered (yes, I know that the table is
> > > not so ordered, but given context suggests to put it after "mei").

Thanks your answers,

I put it between "rapidio" and "ulpi" because mcb_device_id is defined in
mod_devicetable.h between rio_device_id and ulpi_device_id so I though it
could be nice to follow the same order on file2alias.c.

> > 
> > s/after/before/ :)
> 
> Right, good catch!
> 

It is OK to me, I will put it before mei ;)

> -- 
> With Best Regards,
> Andy Shevchenko
> 
> 

Re: [PATCH 2/2] mcb: Remove MODULE_ALIAS from all mcb client drivers

[Jose Javier Rodriguez Barbarin]

On Thu, Nov 27, 2025 at 06:12:29PM +0200, Andy Shevchenko wrote:
> On Thu, Nov 27, 2025 at 5:56 PM Jose Javier Rodriguez Barbarin
> <dev-josejavier.rodriguez@duagon.com> wrote:
> >
> > MODULE_ALIAS information is no longer needed as now all mcb client
> > drivers are reporting such information through MODULE_DEVICE_TABLE.
> 
> While this is not a big change, I still would recommend to split on
> per-driver basis, and with pushing the first one as kinda a fix after
> v6.19-rc1 (to v6.19-rcX) allows other maintainers to apply the rest on
> driver-basis. This helps everybody I assume.
> 

Understood. This was my first patch that touches more than one subsystem
and I was doubting to send one unique patch or one patch per driver. 
Good to know that. 

Thank you so much.

> 
> -- 
> With Best Regards,
> Andy Shevchenko

Re: [PATCH 0/2] mcb: Add modpost support for processing MODULE_DEVICE_TABLE

[Jose Javier Rodriguez Barbarin]

On Thu, Nov 27, 2025 at 06:16:03PM +0200, Andy Shevchenko wrote:
> On Thu, Nov 27, 2025 at 5:56 PM Jose Javier Rodriguez Barbarin
> <dev-josejavier.rodriguez@duagon.com> wrote:
> >
> > During the process of update of one of the device drivers that are part of
> > mcb bus (gpio-menz127.c),
> 
> > one maintainer of the GPIO subsystem
> 
> Krzysztof? Did I miss something and he is now a (co)maintainer here?
> 

I'm sorry, it's my fault, I confused the person who answered me the first time 
with one of the maintainers. Krzysztof and Linus both answered me.

> > asked me
> > why I was adding new MODULE_ALIAS when I also added the same new
> > information on MODULE_DEVICE_TABLE.
> >
> > You can find the messages here:
> >
> > https://lore.kernel.org/linux-gpio/80a20b13-7c6a-4483-9741-568424f957ef@kernel.org/
> >
> > After a deeper analysis, I came across that the mcb_table_id defined inside
> > MODULE_DEVICE_TABLE on all device drivers was being ignored as modpost was
> > not processing the mcb MODULE_DEVICE_TABLE entries. For this reason, former
> > contributors were using MODULE_ALIAS for enabling mcb to autoload the
> > device drivers.
> >
> > My proposal with these changes is to complete the mcb bus by adding
> > modpost support for processing mcb MODULE_DEVICE_TABLE and removing
> > MODULE_ALIAS from all device drivers as they are no longer needed.
> >
> > Jose Javier Rodriguez Barbarin (2):
> >   mcb: Add missing modpost build support
> >   mcb: Remove MODULE_ALIAS from all mcb client drivers
> >
> >  drivers/gpio/gpio-menz127.c            | 1 -
> >  drivers/iio/adc/men_z188_adc.c         | 1 -
> >  drivers/tty/serial/8250/8250_men_mcb.c | 3 ---
> >  drivers/tty/serial/men_z135_uart.c     | 1 -
> >  drivers/watchdog/menz69_wdt.c          | 1 -
> >  scripts/mod/devicetable-offsets.c      | 3 +++
> >  scripts/mod/file2alias.c               | 9 +++++++++
> >  7 files changed, 12 insertions(+), 7 deletions(-)
> >
> > --
> > 2.51.1
> 
> 
> 
> -- 
> With Best Regards,
> Andy Shevchenko

Thanks for you review, I will send a V2 following your suggestions.

Regards,

Javier Rodriguez.