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Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem

Previous thread: question regarding user mode linux by thomas on Sunday, January 13, 2008 - 10:24 am. (2 messages)

Next thread: iwlwifi 1.2.23 vs. kernel 2.6.23.13 by Mario Guenterberg on Sunday, January 13, 2008 - 11:05 am. (1 message)
[view original message]
From: Jean Delvare <khali@...>
To: Jon Smirl <jonsmirl@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 10:27 am

Can you please explain what this patch does and why it is needed?


--

Jean Delvare

--
[view original message]
From: Jon Smirl <jonsmirl@...>
To: Jean Delvare <khali@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 11:14 am

It generates the entries needed for the user space module tools to

work with the aliases. For example modprobe/depmod. It is a standard

part of the kernel module system.


--

Jon Smirl

jonsmirl@gmail.com

--
[view original message]
From: Jean Delvare <khali@...>
To: Jon Smirl <jonsmirl@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 11:35 am

What entries, where? What can you do after applying your patch that you

couldn't do before?


I'm asking because automatic i2c driver loading works just fine for me

without patching user-space. So I don't get why your want to change

anything.


--

Jean Delvare

--
[view original message]
From: Jon Smirl <jonsmirl@...>
To: Jean Delvare <khali@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 12:26 pm

--

Jon Smirl

jonsmirl@gmail.com

--
[view original message]
From: Jean Delvare <khali@...>
To: Jon Smirl <jonsmirl@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 1:43 pm

They do. I'm testing with the lm90 driver, which depends on the hwmon

driver. Both load automatically when the underlying i2c-parport driver

instantiate an "adm1032" i2c device.


--

Jean Delvare

--
[view original message]
From: Jon Smirl <jonsmirl@...>
To: Jean Delvare <khali@...>
Cc: <i2c@...>, <linuxppc-dev@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Sunday, January 13, 2008 - 2:04 pm

I don't know exactly what those modules tables are used for. I just

copied what the other subsystems do. Maybe they are used when you make

an initrd to know which drivers to copy into the image.


--

Jon Smirl

jonsmirl@gmail.com

--
[view original message]
From: Geert Uytterhoeven <Geert.Uytterhoeven@...>
To: Jon Smirl <jonsmirl@...>
Cc: Jean Delvare <khali@...>, <linuxppc-dev@...>, <i2c@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 6:57 am

Module-init-tools needs those table to create module aliases in the *.ko

files from the MODULE_DEVICE_TABLE(), so udev can load the modules based

on the device IDs when the devices appear in sysfs.


That's the generic part. How this applies to i2c devices on platforms

without Open Firmware device trees is another question. I guess that's

where Jean gets confused (i2c_device_id got _removed_ last year,

because it didn't make sense (at the time?)).


With kind regards,


Geert Uytterhoeven

Software Architect


Sony Network and Software Technology Center Europe

The Corporate Village
[view original message]
From: Jean Delvare <khali@...>
To: Geert Uytterhoeven <Geert.Uytterhoeven@...>
Cc: Jon Smirl <jonsmirl@...>, <linuxppc-dev@...>, <i2c@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 12:38 pm

Hi Geert,


I thought that the module aliases were generated by

scripts/mod/modpost? As a matter of fact, I did not apply Jon's patch

to module-init-tools, and "modinfo" shows me module aliases properly

for i2c drivers that call MODULE_DEVICE_TABLE():


$ /sbin/modinfo lm90

filename:       /lib/modules/2.6.24-rc7-git4/kernel/drivers/hwmon/lm90.ko

author:         Jean Delvare <khali@linux-fr.org>

description:    LM90/ADM1032 driver

license:        GPL

vermagic:       2.6.24-rc7-git4 mod_unload

depends:        hwmon

alias:          i2c:Nlm90*

alias:          i2c:Nadm1032*

alias:          i2c:Nlm99*

alias:          i2c:Nlm86*

alias:          i2c:Nmax6657*

alias:          i2c:Nadt7461*

alias:          i2c:Nmax6680*

$


The way it was implemented back then did not make sense. As it was not

clear whether we would implement something different or nothing at all,

I decided to plain remove it. Now that it seems that we want to

implement it differently, I'm looking into it again.


--

Jean Delvare

--
[view original message]
From: Geert Uytterhoeven <Geert.Uytterhoeven@...>
To: Jean Delvare <khali@...>
Cc: <linuxppc-dev@...>, <linux-kernel@...>, <i2c@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 1:08 pm

I've just looked it up again (I had to do a similar thing for Zorro bus

support).  Module-init-tools (depmod) also creates the modules.*map files,

which are used to map from device IDs to module names. I think these are used

by udev to load the appropriate module when a device with a specific device ID


Yes, it's also still not 100% clear to me when `i2c:Nadm1032' is used, and when

modules.i2cmap would be used...


With kind regards,


Geert Uytterhoeven

Software Architect


Sony Network and Software Technology Center Europe

The Corporate Village
[view original message]
From: Jean Delvare <khali@...>
To: Geert Uytterhoeven <Geert.Uytterhoeven@...>
Cc: <linuxppc-dev@...>, <linux-kernel@...>, <i2c@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 1:50 pm

Ah, right. I see it now, there's modules.isapnpmap,

modules.ieee1394map, modules.pcimap etc. but no modules.i2cmap.

However, there is modules.alias which contains the i2c aliases for all

device types (including one ieee1394 and many pci aliases) which seems


I am under the impression that modules.*map are the old way to get

automatic driver loading and aliases are the new way to do the same.

But maybe that's just me.


--

Jean Delvare

--
[view original message]
From: Kay Sievers <kay.sievers@...>
To: Jean Delvare <khali@...>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@...>, <linuxppc-dev@...>, <linux-kernel@...>, <i2c@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 3:38 pm

Right, nothing on recent systems is using the map files. This patch

should not be needed.

The plan is to deprecate the creation of these files in depmod.


Thanks,

Kay

--
[view original message]
From: Jean Delvare <khali@...>
To: Kay Sievers <kay.sievers@...>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@...>, <linuxppc-dev@...>, <linux-kernel@...>, <i2c@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 3:46 pm

OK, great. Thanks for the info, Kay!


--

Jean Delvare

--
[view original message]
From: Jon Smirl <jonsmirl@...>
To: Geert Uytterhoeven <Geert.Uytterhoeven@...>
Cc: Jean Delvare <khali@...>, <linuxppc-dev@...>, <i2c@...>, <linux-kernel@...>
Subject: Re: [i2c] [PATCH] update module-init-tools to support the i2c subsystem
Date: Monday, January 14, 2008 - 10:25 am

--

Jon Smirl

jonsmirl@gmail.com

--
Previous thread: question regarding user mode linux by thomas on Sunday, January 13, 2008 - 10:24 am. (2 messages)

Next thread: iwlwifi 1.2.23 vs. kernel 2.6.23.13 by Mario Guenterberg on Sunday, January 13, 2008 - 11:05 am. (1 message)