Messages in this thread | | | Date | Mon, 15 Jun 2015 10:01:29 -0600 | From | Stephen Warren <> | Subject | Re: [RESEND PATCH 2/2] pinctrl: introduce complex pin description |
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On 06/10/2015 09:04 AM, Ludovic Desroches wrote: > Using a string to describe a pin in the device tree can be not enough. > Some controllers may need extra information to fully describe a pin. It > concerns mainly controllers which have a per pin muxing approach which > don't fit well the notions of groups and functions. > Instead of using a pin name, a 32 bit value is used. The 16 least > significant bits are used for the pin number. Other 16 bits can be used to > store extra parameters.
The driver for the pin controller is supposed to provide this information in a table. The whole point of having a driver, rather than a table/list of raw register values in the DT, is so the driver can provide this information at a semantic level. This information is fixed per SoC and so make sense to put into a driver, while the board-specific configuration varies wildly, and hence makes sense to put into DT.
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