[cmd] clarification on syntax of 'chpart' command

Wolfgang Denk wd at denx.de
Fri May 7 08:45:58 CEST 2021

Dear Adarsh,

In message <CAJgxa7eTn4L5Jbg2YbDExPFc1_69viALtW2YQYHj9VsU7xzQbA at mail.gmail.com> you wrote:
> I was trying to verify and use 'chpart' command on Beaglebone black with an
> SDHC card ( with multiple partitions ) and am unable to get its exact
> syntax.Is this command applicable to
> any particular category of storage devices (viz. NOR flash,NAND flash etc)??

I agree that it is not obvious from the help output, but the fact
that the chpart command is implemented in the cmd/mtdparts.c source
file gives a clear hint: it works only for MTD devices, not for
general storage devides using DOS (or GPT) partitions.

> => mmc dev 0
> switch to partitions #0, OK
> mmc0 is current device

This is what you should look for.  THe help output shoud tell you:

	mmc dev [dev] [part] - show or set current mmc device [partition]

So instead of

> => chpart mmc0:2
> Device nand0 not found!

you would use:

	=> mmc dev 0 2

Hope this helps.

Wolfgang Denk

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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