Unverified Commit efe30e2c authored by Richard Fitzgerald's avatar Richard Fitzgerald Committed by Mark Brown
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ASoC: soc-utils: Improve kerneldoc for snd_soc_tdm_params_to_bclk() 



The statement that snd_soc_tdm_params_to_bclk() is equivalent to
snd_soc_params_to_bclk() if tdm_width==tdm_slots==0 is not accurate,
it is only true is slot_multiple is also <2.

However, the description of special-case behaviour in terms of pairs of
tdm_width and tdm_slot values is not particularly helpful so we might as
well take the opportunity to rework the description to say the same thing
in a simpler way. The behaviour of a pair of values is obvious from a
description of each argument. At the same time make a few edits to clarify
the rest of the description.

Signed-off-by: default avatarRichard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220815113346.3805075-1-rf@opensource.cirrus.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 36b99942

sound/soc/soc-utils.c

+12 −11
Original line number Diff line number Diff line
@@ -56,23 +56,24 @@ EXPORT_SYMBOL_GPL(snd_soc_params_to_bclk); 
/**

 * snd_soc_tdm_params_to_bclk - calculate bclk from params and tdm slot info.

 *

 * Calculate the bclk from the params sample rate and the tdm slot count and

 * tdm slot width. Either or both of tdm_width and tdm_slots can be 0.

 * Calculate the bclk from the params sample rate, the tdm slot count and the

 * tdm slot width. Optionally round-up the slot count to a given multiple.

 * Either or both of tdm_width and tdm_slots can be 0.

 *

 * If tdm_width == 0 and tdm_slots > 0:	the params_width will be used.

 * If tdm_width > 0 and tdm_slots == 0:	the params_channels will be used

 *					as the slot count.

 * Both tdm_width and tdm_slots are 0:	this is equivalent to calling

 *					snd_soc_params_to_bclk().

 * If tdm_width == 0:	use params_width() as the slot width.

 * If tdm_slots == 0:	use params_channels() as the slot count.

 *

 * If slot_multiple > 1 the slot count (or params_channels if tdm_slots == 0)

 * will be rounded up to a multiple of this value. This is mainly useful for

 * If slot_multiple > 1 the slot count (or params_channels() if tdm_slots == 0)

 * will be rounded up to a multiple of slot_multiple. This is mainly useful for

 * I2S mode, which has a left and right phase so the number of slots is always

 * a multiple of 2.

 *

 * If tdm_width == 0 && tdm_slots == 0 && slot_multiple < 2, this is equivalent

 * to calling snd_soc_params_to_bclk().

 *

 * @params:        Pointer to struct_pcm_hw_params.

 * @tdm_width:     Width in bits of the tdm slots.

 * @tdm_slots:     Number of tdm slots per frame.

 * @tdm_width:     Width in bits of the tdm slots. Must be >= 0.

 * @tdm_slots:     Number of tdm slots per frame. Must be >= 0.

 * @slot_multiple: If >1 roundup slot count to a multiple of this value.

 *

 * Return: bclk frequency in Hz, else a negative error code if params format