On Mon, Sep 28, 2015 at 04:16:12PM +0800, sugar wrote: > ? 9/24/2015 00:24, Mark Brown ??: > >My initial thought here is that the machine driver should be responsible > >for setting this and then the DAI driver should check to see if > >symmetric_rates are in use and configure itself appropriately. Is there > >a reason why this won't work here? > It's for i2s ip configuration, in the most situation, there is no need > to use this property, except one case: > In order to save gpio pins for other function use, we may use single > lrck(tx or rx) pin. of course, it depends on product design. when in i2s > slave mode, we need to configure this to share lrck with tx/rx inside i2s > logic. > symmetric_rates flag works fine on rockchip platform, but it can't cover the > above case. > Do you have any suggestion about this or maybe there is no need to upstream > this special part? What makes you say that the symmetric_rates flag can't be used to cover this case? What you describe above is hte normal reason for needing to enforce symmetric_rates. The driver should be able to check if the flag has been set just as well as the core is. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 473 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-rockchip/attachments/20150930/e8e96976/attachment.sig>
