topology: nhlt: ssp-nhlt: Set link clock source based on bclk_freq #198
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There is no need to set this in topology as this can be derived based on whether the bit clock frequency is derived from 19.2MHz or 24.576MHz. Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
| if (!(19200000 % bclk_freq)) | ||
| ssp_link_set_params(nhlt, 0); | ||
| else if (!(24576000 % bclk_freq)) | ||
| ssp_link_set_params(nhlt, 1); |
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Not 100% sure we want to hardcode this in the plugin (but agree this is a cleaner implementation in topology).
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yeah, we should not hardcode HW specific details as this assumes the BCLK never has a fractional divider from MCLK.
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it never does @lgirdwood, we never used M/N dividers. Integer division is the only thing we've ever used.
@ranj063 this is a valid assumption if the SOC provides the MCLK, likely 99% of usages. However, there's also the possibility of using an external clock, see "011b: MCLK input" so we need a escape to deal with this case as well. Sorry to bring the exception to the rule, I just thought about it now. If the goal is to avoid setting this all the time, I wonder if we should have a default in the topology base class and override it as needed. It might be more future proof that a change of tools required? |
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closing this one in favor of thesofproject/sof#7370. Thanks everyone for the feedback |
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There is no need to set this in topology as this can be derived based on whether the bit clock frequency is derived from 19.2MHz or 24.576MHz.