From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jyri Sarha Subject: Re: [PATCH RFC 4/5] ASoC: davinci-mcasp: Get rid of bclk_lrclk_ratio in private data Date: Thu, 10 Sep 2015 10:16:30 +0300 Message-ID: <55F12E4E.9020607@ti.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, peter.ujfalusi-l0cyMroinI0@public.gmane.org, liam.r.girdwood-VuQAYsv1563Yd54FQh9/CA@public.gmane.org, bcousson-rdvid1DuHRBWk0Htik3J/w@public.gmane.org, misael.lopez-l0cyMroinI0@public.gmane.org List-Id: alsa-devel@alsa-project.org On 09/09/15 21:27, Jyri Sarha wrote: > The slot_width is for essentially same thing. Instead of storing > bclk_lrclk_ratio, just store the slot_width. Comments has been updated > accordingly and some variable names changed to more descriptive. > > Signed-off-by: Jyri Sarha > --- > sound/soc/davinci/davinci-mcasp.c | 56 ++++++++++++++++++++++----------------- > 1 file changed, 31 insertions(+), 25 deletions(-) > > diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c > index de1e3a8..25ff1fc 100644 > --- a/sound/soc/davinci/davinci-mcasp.c > +++ b/sound/soc/davinci/davinci-mcasp.c > @@ -87,7 +87,6 @@ struct davinci_mcasp { > u8 *serial_dir; > u8 version; > u8 bclk_div; > - u16 bclk_lrclk_ratio; > int streams; > u32 irq_request[2]; > int dma_request[2]; > @@ -558,8 +557,21 @@ static int __davinci_mcasp_set_clkdiv(struct snd_soc_dai *dai, int div_id, > mcasp->bclk_div = div; > break; > > - case 2: /* BCLK/LRCLK ratio */ > - mcasp->bclk_lrclk_ratio = div; > + case 2: /* > + * BCLK/LRCLK ratio descries how many bit-clock cycles > + * fit into one frame. The clock ratio is given for a > + * full period of data (for I2S format both left and > + * right channels), so it has to be divided by number > + * of tdm-slots (for I2S - divided by 2). > + * Instead of storing this ratio, we calculate a new > + * tdm_slot width by dividing the the ratio by the > + * number of configured tdm slots. > + */ > + mcasp->slot_width = div / mcasp->tdm_slots; > + if (div % mcasp->tdm_slots) > + dev_warn(mcasp->dev, > + "%s(): BCLK/LRCLK %d is not divisible by %d tdm slots", > + div, mcasp->tdm_slots); Oops, there is a __func__ missing here. > break; > > default: > @@ -682,11 +694,13 @@ static int davinci_mcasp_set_tdm_slot(struct snd_soc_dai *dai, > } > > static int davinci_config_channel_size(struct davinci_mcasp *mcasp, > - int word_length) > + int sample_width) > { > u32 fmt; > - u32 tx_rotate = (word_length / 4) & 0x7; > - u32 mask = (1ULL << word_length) - 1; > + u32 tx_rotate = (sample_width / 4) & 0x7; > + u32 mask = (1ULL << sample_width) - 1; > + u32 slot_width = sample_width; > + > /* > * For captured data we should not rotate, inversion and masking is > * enoguh to get the data to the right position: > @@ -699,31 +713,23 @@ static int davinci_config_channel_size(struct davinci_mcasp *mcasp, > u32 rx_rotate = 0; > > /* > - * if s BCLK-to-LRCLK ratio has been configured via the set_clkdiv() > - * callback, take it into account here. That allows us to for example > - * send 32 bits per channel to the codec, while only 16 of them carry > - * audio payload. > - * The clock ratio is given for a full period of data (for I2S format > - * both left and right channels), so it has to be divided by number of > - * tdm-slots (for I2S - divided by 2). > + * Setting the tdm slot width either with set_clkdiv() or > + * set_tdm_slot() allows us to for example send 32 bits per > + * channel to the codec, while only 16 of them carry audio > + * payload. > */ > - if (mcasp->bclk_lrclk_ratio) { > - u32 slot_length = mcasp->bclk_lrclk_ratio / mcasp->tdm_slots; > - > + if (mcasp->slot_width) { > /* > - * When we have more bclk then it is needed for the data, we > - * need to use the rotation to move the received samples to have > - * correct alignment. > + * When we have more bclk then it is needed for the > + * data, we need to use the rotation to move the > + * received samples to have correct alignment. > */ > - rx_rotate = (slot_length - word_length) / 4; > - word_length = slot_length; > - } else if (mcasp->slot_width) { > - rx_rotate = (mcasp->slot_width - word_length) / 4; > - word_length = mcasp->slot_width; > + slot_width = mcasp->slot_width; > + rx_rotate = (slot_width - sample_width) / 4; > } > > /* mapping of the XSSZ bit-field as described in the datasheet */ > - fmt = (word_length >> 1) - 1; > + fmt = (slot_width >> 1) - 1; > > if (mcasp->op_mode != DAVINCI_MCASP_DIT_MODE) { > mcasp_mod_bits(mcasp, DAVINCI_MCASP_RXFMT_REG, RXSSZ(fmt), > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html