[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Ben Warren]

Hello,

Attached is a patch providing support for multiple I2C buses at the
command level.  The second part of the patch includes an implementation
for the MPC834x CPU and MPC8349EMDS board.  Note - this does not include
support for 10-bit addresses.  That's too profound a change to include
here...  Hopefully this addresses concerns with my previous attempts.

Overview:

1. Include new 'i2c' command (based on USB implementation) using
CONFIG_I2C_CMD_TREE.  Note - I opted to not use the last remaining CMD
bit in 'include/cmd_confdefs.h'.

2. Allow multiple buses by defining CONFIG_I2C_MULTI_BUS.  Note that
this is only available under the new 'i2c' command mentioned in bullet
1.  

3. Allow by-passing of devices when probing a bus by defining
CFG_I2C_MULTI_NOPROBES.  This is an array of bus-device pairs that will
be skipped by the 'i2c probe' command. 

CHANGELOG:
        Added new 'i2c' master command for all I2C interaction.  This is
conditionally compiled with CONFIG_I2C_CMD_TREE.  New commands added for
setting I2C bus speed as well as changing the active bus if the board
has more than one bus (conditionally compiled with
CONFIG_I2C_MULTI_BUS).  Added a list of devices to ignore when probing
the buses when more than one bus is present.  Updated README.

regards,
Ben
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[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Nishanth Menon]

Ben Warren stated on 8/30/2006 4:35 PM:

> Overview:
<snip>
> be skipped by the 'i2c probe' command. 
Thanks Ben, this is finally in tune with Denx requirements I guess ;)
> ------------------------------------------------------------------------
> 
> diff --git a/README b/README
> index e772c1a..f674050 100644
> --- a/README
> +++ b/README
> @@ -1188,7 +1188,12 @@ The following options need to be configu
>  		clock chips. See common/cmd_i2c.c for a description of the
>  		command line interface.
>  
> -		CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
> +		CONFIG_I2C_CMD_TREE is a recommended option that places
> +		all I2C commands under a single 'i2c' root command.  The 
> +		older 'imm', 'imd', 'iprobe' etc. commands are considered
> +		deprecated and may disappear in the future.
> +
> +		CONFIG_HARD_I2C selects a hardware I2C controller.
I guess I am slow abt this.... but !slow_i2c... is that not good enough?
and I cant see any other part in the the common patch using it...
> diff --git a/common/cmd_i2c.c b/common/cmd_i2c.c
> index c543bb5..824f7c7 100644
> --- a/common/cmd_i2c.c
> +++ b/common/cmd_i2c.c

> +int do_i2c_bus_speed(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
> +{
> +	int speed, ret=0;
> +
> +	if (argc == 1)  /* querying current speed */
> +	{
> +		printf("Current bus speed=%d\n", i2c_get_bus_speed());
> +	}
> +	else
> +	{
> +		speed = simple_strtoul(argv[1], NULL, 10);
> +		printf("Setting bus speed to %d Hz\n", speed);
> +		ret = i2c_set_bus_speed(speed);
> +		if(ret)
> +		{
> +			printf("Failure changing bus speed (%d)\n", ret);
> +		}
> +	}
> +	return ret;
> +}
Err... Does this mean that all other folks who can only support a single
speed need to implement this api (including all other existing
drivers??)...... Lotsa people are not going to like this if that is so...


Looks good to me.. it should fit in OMAP2430 framework too :)

Some one gotta tell Denx  to update this:
http://sourceforge.net/cvs/?group_id=65938. i thought we moved to git
sometime back. Do we even look at cvs anymore??? :(

Regards,
Nishanth Menon

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Ben Warren]

On Thu, 2006-08-31 at 22:45 -0500, Nishanth Menon wrote:
> Ben Warren stated on 8/30/2006 4:35 PM:
> 
> > Overview:
> <snip>
> > be skipped by the 'i2c probe' command. 
> Thanks Ben, this is finally in tune with Denx requirements I guess ;)
Hope so...
> > ------------------------------------------------------------------------
> > 
> > diff --git a/README b/README
> > index e772c1a..f674050 100644
> > --- a/README
> > +++ b/README
> > @@ -1188,7 +1188,12 @@ The following options need to be configu
> >  		clock chips. See common/cmd_i2c.c for a description of the
> >  		command line interface.
> >  
> > -		CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
> > +		CONFIG_I2C_CMD_TREE is a recommended option that places
> > +		all I2C commands under a single 'i2c' root command.  The 
> > +		older 'imm', 'imd', 'iprobe' etc. commands are considered
> > +		deprecated and may disappear in the future.
> > +
> > +		CONFIG_HARD_I2C selects a hardware I2C controller.
> I guess I am slow abt this.... but !slow_i2c... is that not good enough?
> and I cant see any other part in the the common patch using it...
Sorry, I don't know what you're talking about.  What's slow_i2c?  I just
grepped the source and didn't find it anywhere.
> > diff --git a/common/cmd_i2c.c b/common/cmd_i2c.c
> > index c543bb5..824f7c7 100644
> > --- a/common/cmd_i2c.c
> > +++ b/common/cmd_i2c.c
> 
> > +int do_i2c_bus_speed(cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
> > +{
> > +	int speed, ret=0;
> > +
> > +	if (argc == 1)  /* querying current speed */
> > +	{
> > +		printf("Current bus speed=%d\n", i2c_get_bus_speed());
> > +	}
> > +	else
> > +	{
> > +		speed = simple_strtoul(argv[1], NULL, 10);
> > +		printf("Setting bus speed to %d Hz\n", speed);
> > +		ret = i2c_set_bus_speed(speed);
> > +		if(ret)
> > +		{
> > +			printf("Failure changing bus speed (%d)\n", ret);
> > +		}
> > +	}
> > +	return ret;
> > +}
> Err... Does this mean that all other folks who can only support a single
> speed need to implement this api (including all other existing
> drivers??)...... Lotsa people are not going to like this if that is so...

Yes.  If you want to use the new command tree, you'll have to add a
small number of stub functions to your driver.  Or else use the old
commands.  Although I've mentioned deprecation, I suspect they'll be
around longer than you or me.  I guess if there's huge pushback we can
always wrap these calls by yet another CONFIG option, but aren't there
enough already?
> 
> Looks good to me.. it should fit in OMAP2430 framework too :)
> 
> Some one gotta tell Denx  to update this:
> http://sourceforge.net/cvs/?group_id=65938. i thought we moved to git
> sometime back. Do we even look at cvs anymore??? :(
> 
Wolfgang has mentioned MANY times to people that the CVS isn't in use
any more and to use git.  I suspect it's hard if not impossible to
remove that from Sourceforge, and obviously Wolfgang has lots of things
on his plate that have a priority...

> Regards,
> Nishanth Menon

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Wolfgang Denk]

In message <1157139773.13685.113.camel@saruman.qstreams.net> you wrote:
>
> Wolfgang has mentioned MANY times to people that the CVS isn't in use
> any more and to use git.  I suspect it's hard if not impossible to
> remove that from Sourceforge, and obviously Wolfgang has lots of things
> on his plate that have a priority...

It's impossible to remove  (and  does  not  ake  sense  -  IMHO  it's
actually  a  very  good thing that projects cannot just disappear for
example if someone retires or ries to convert it to another, non-open
license model). Also, the web page mentioned cannot be edited by  me,
as it's one of the common site docs.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
If all you have is a hammer, everything looks like a nail.

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Tolunay Orkun]

Wolfgang,

Wolfgang Denk wrote:
> In message <1157139773.13685.113.camel@saruman.qstreams.net> you wrote:
>> Wolfgang has mentioned MANY times to people that the CVS isn't in use
>> any more and to use git.  I suspect it's hard if not impossible to
>> remove that from Sourceforge, and obviously Wolfgang has lots of things
>> on his plate that have a priority...
> 
> It's impossible to remove  (and  does  not  ake  sense  -  IMHO  it's
> actually  a  very  good thing that projects cannot just disappear for
> example if someone retires or ries to convert it to another, non-open
> license model). Also, the web page mentioned cannot be edited by  me,
> as it's one of the common site docs.

How about adding a warning text to the Makefile on CVS repository so that if 
someone checks out from CVS and does a build they are given warning that CVS 
repository is obsolete and they should use git repository only at denx.de

Best regards,
Tolunay

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[nishanth menon]

On 9/1/06, Ben Warren <bwarren@qstreams.com> wrote:
> > > +           CONFIG_HARD_I2C selects a hardware I2C controller.
> > I guess I am slow abt this.... but !slow_i2c... is that not good enough?
> > and I cant see any other part in the the common patch using it...
> Sorry, I don't know what you're talking about.  What's slow_i2c?  I just
> grepped the source and didn't find it anywhere.
Voila, a typo :-) ! I should have stated soft_i2c. !CONFIG_SOFT_I2C
should mean HARD_I2C.
Regards,
Nishanth Menon

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Ben Warren]

Nishanth,

--- nishanth menon <menon.nishanth@gmail.com> wrote:

> On 9/1/06, Ben Warren <bwarren@qstreams.com> wrote:
> > > > +           CONFIG_HARD_I2C selects a hardware
> I2C controller.
> > > I guess I am slow abt this.... but !slow_i2c...
> is that not good enough?
> > > and I cant see any other part in the the common
> patch using it...
> > Sorry, I don't know what you're talking about. 
> What's slow_i2c?  I just
> > grepped the source and didn't find it anywhere.
> Voila, a typo :-) ! I should have stated soft_i2c.
> !CONFIG_SOFT_I2C
> should mean HARD_I2C.
> Regards,
> Nishanth Menon

OK... look a little more closely at the diff.  All I
did was change the word 'CPM' to 'hardware', because
nowadays there are many more I2C controllers than the
ones in QUICC engines.  I was just cleaning up
documentation, and didn't change any code regarding
either HARD_I2C or SOFT_I2C.

Sorry for the confusion,
Ben

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Nishanth Menon]

Hi Ben,
Ben Warren stated on 9/1/2006 10:18 PM:
> OK... look a little more closely at the diff.  All I
> did was change the word 'CPM' to 'hardware', because
Accepted :) But I still in my naivete question the sense of
CONFIG_HARD_I2C? what is !HARD_I2C && !SOFT_I2C??
Regards,
Nishanth Menon

[U-Boot-Users] [PATCH 1/2] Add support for multiple I2C buses

[Ben Warren]

Hello,

Attached is a patch providing support for multiple I2C buses at the
command level.  The second part of the patch includes an implementation
for the MPC834x CPU and MPC8349EMDS board.

/*** Note: This patch replaces ticket DNX#2006083042000018 ***/

Signed-off-by: Ben Warren <bwarren@qstreams.com>

Overview:

1. Include new 'i2c' command (based on USB implementation) using
CONFIG_I2C_CMD_TREE.  

2. Allow multiple buses by defining CONFIG_I2C_MULTI_BUS.  Note that
the commands to change bus number and speed are only available under the
new 'i2c' command mentioned in the first bullet.

3. The option CFG_I2C_NOPROBES has been expanded to work in multi-bus
systems.  When CONFIG_I2C_MULTI_BUS is used, this option takes the form
of an array of bus-device pairs.  Otherwise, it is an array of uchar. 

CHANGELOG:
        Added new 'i2c' master command for all I2C interaction.  This is
conditionally compiled with CONFIG_I2C_CMD_TREE.  New commands added for
setting I2C bus speed as well as changing the active bus if the board
has more than one (conditionally compiled with
CONFIG_I2C_MULTI_BUS).  Updated NOPROBE logic to handle multiple buses.
Updated README.

regards,
Ben

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