[U-Boot] [PATCH v4 15/15] dm: Expand and improve the device lifecycle docs

Pavel Herrmann morpheus.ibis at gmail.com
Fri Jun 6 21:52:53 CEST 2014


Hi,

I found some typos in this

On Friday 06 of June 2014 13:13:32 Simon Glass wrote:
> The lifecycle of a device is an important part of driver model. Add to the
> existing documentation and clarify it.

...snip...

> +This means that instead of having lots of U_BOOT_DEVICE() declarations in
> +the board file, we put these in the device tree. This approach allows a lot
> +more generality, since the same board file can support many types of
> boards +(e,g. with the same SoC) just by using different device trees. An
> added +benefit is that the Linux device tree can be used, thus further
> simplifying +the task of board-bring up either for U-Boot or Linux devs
> (whoever gets to +the baord first!).

s/baord/board/

...snip...

> +Note that compared to Linux, U-Boot's driver model has a separate step of
> +probe/remove which is independent of bind/unbind. This is partly because in
> +U-Boot it may be expensive to prove devices and we don't want to do it
> until +they are needed, or perhaps until after relocation.

s/prove/probe/

...snip...

> +   d. All parent devices are probed. It is not possible to activate a
> device +   unless its parents (all the way up to the root device) are
> activated. +   This means (for example) that an I2C driver will require
> that its bus +   be activated.
s/parents/predecessors/
in a tree, a node can have up to one parent. parent of a parent (recursively) 
is a predecessor.

...snip...

> +   e. The device is marked inactive. Note that it is still bound, so the
> +   device structure itself is not freed at this point. Should the device be
> +   activated again, then the cycle starts again at step 4 above.

if there were no drastic changes since I last checked, this would go to 
activation/probe(), which is described in step 2


regards
Pavel Herrmann


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