[RFC 3/8] mfd:syscon: Introduce claim/read/write/release APIs

Srinivas KANDAGATLA srinivas.kandagatla at st.com
Wed May 8 13:42:04 EDT 2013


Thankyou for the comments.
On 08/05/13 16:01, Mark Brown wrote:
> On Wed, May 08, 2013 at 04:50:22PM +0200, Arnd Bergmann wrote:
>
>>> In many cases a single syconf register contains bits related to multiple
>>> devices, and therefore it need to be shared across multiple drivers at
>>> bit level. The same IP block can have different syscon mappings on
>>> different SOCs.
>> My feeling is that syscon is the wrong place for this functionality,
>> since regmap already handles (some of?) these issues. If you need
>> additional synchronization, it's probably best to extend regmap
>> as needed so other code besides syscon can take advantage of that
>> as well.
> This sounds like regmap_update_bits() ought to be all that's needed.

Ultimately the syscon_write use the regmap_update_bits, however we really want is the flexibility in using/referring the syscon registers/bits in both device-trees and non-device tree cases.

The reason for these APIs, is the extent of syscon usage is very high in ST set-top-box parts.

Without these new APIs, its very difficult to pass this information to
the drivers.

Thanks,
srini



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