[RFC PATCH 3/3] Enable BCM2835 mailbox support

Craig McGeachie slapdau at yahoo.com.au
Wed Jul 2 01:51:36 PDT 2014

On 01/07/14 04:06, Lubomir Rintel wrote:
> I'm wondering if there's a reason you're not getting the channel with
> ipc_request_channel() (that would be mbox_request_channel() in current
> version of the framework) at the probe time, but each time you send a
> message with do_message()?

It's a good question.  Given that it was 9 months ago, I can't be sure. 
  Still, I think that it was because of the nature of the property 
channel for the bcm2835 mailbox, which is used for a variety of 
purposes.  The two uses that I had in mind were, thermal (get 
temperatures) and DMA (query the DMA channels available for use by the 
ARM core).  I think there are also video buffer messages on the property 
channel as well ,but those might be on a separate channel.  Regardless, 
there are a lot of things done on the property channel and if one driver 
holds onto that channel, other drivers will be hard to get working 

Please feel free to check up on this.  Memory is dodgy.


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