[U-Boot-Users] soft_i2c and ds1307 with tqm823l
wd at denx.de
Mon Jun 30 14:39:29 CEST 2003
in message <3F002BCA.9070609 at peak.uklinux.net> you wrote:
> I'm working on getting a ds1307 realtime clock working with a tqm823l as
> a new user to u-boot (I've never compiled u-boot or ppcboot before).
This is not correct. You compiled and installed PPCBoot in our
training a year and a couple of days ago :-)
> Firstly, the ds1307 code compiles fine, but of course it needs the i2c
> code to be compiled alongside it. Although this is obvious, the newcomer
> to u-boot doesn't (i.e. I didn't) know that calling for ds1307.c to be
> compiled doesn't in itself cause the i2c code to be compiled, so a note
> to this effect in the realtime clock section of the README would be a
> helpful addition.
Please feel free to submit a patch...
> Here's a line from the README (starting at line 907):
> "If this is selected, either CONFIG_HARD_I2C or CONFIG_SOFT_I2C must
> be defined to include the appropriate I2C driver."
> No mention is made of what values the 'appropriate driver' might have or
> where to look for them. I assume you might define something like this:
> #define CONFIG_HARD_I2C mpc8xx
No. Just "#define CONFIG_HARD_I2C" is OK, as for each CPU there is
always exactly one hard-i2c and one soft-i2c driver.
> But I can't see what you'd write for CONFIG_SOFT_I2C. A bit more
> clarification here would be useful.
It must be defined - that's all :-)
> There are a number of extra defines related to CONFIG_SOFT_I2C, such as
> I2C_INIT, I2C_PORT, etc. It's not too clear what these should be set to.
> The diff between my TQM823L.h and the original TQM823L.h is (also
> attached as changes.diff):
No diff attached.
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd at denx.de
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make it so simple that there are obviously no deficiencies and the
other is to make it so complicated that there are no obvious defi-
ciencies. - Charles Anthony Richard Hoare
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