On 02/14/2017 06:45 PM, Mark Brown wrote:
On Mon, Feb 13, 2017 at 05:38:27PM +0100, Arnaud Pouliquen wrote:
This looks basically fine as a system specific driver but as some of the comments in here say there's bits of it could perhaps be genericised but I'm not sure we need to do that right now. I'm not sure the abstraction is exactly comfortable but having another bit of hardware doing a bridge to IIO might be the best way to figure out something better.
Yes this is one point to clarify. I keep it as a specific API, as i don't know if another hardware needs to support it... I would say that objective of this version is to highlight interactions. Then i can rework it in a way that could be genericised in future ( i.e. using void* for params that would depend on platforms)...
Extend IIO customer API would be also another alternative, but i did not find a generic way to do it. Some IIO attributes could be used for Hw params but DMA and IRQs seems tricky to handle through this IIO interface...
- .period_bytes_min = 40, /* 8 khz 5 ms */ + .period_bytes_max =
4 * PAGE_SIZE, + .buffer_bytes_max = 16 * PAGE_SIZE
What's the physical minimum period limit? The comment makes this sound like it's just made up.
I did not find physical minimum period limit, that why i considered this value from a scheduling point of view. I will re-check these values.
- unsigned int shift = 24 -priv->max_scaling; +
Missing space after -.
- dev_dbg(dai->dev, "%s: enter\n", __func__); + return 0; +
return snd_pcm_hw_constraint_list(substream->runtime, 0, + SNDRV_PCM_HW_PARAM_RATE, + &priv->rates_const);
Looks like debug changes got left in?
yes exactly...
+static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id, + unsigned int freq, int dir) +{ + struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai); + struct stm32_adfsdm_pdata *pdata = priv->pdata; + + dev_dbg(dai->dev, "%s: enter for dai %d\n", __func__, dai->id); + if (dir == SND_SOC_CLOCK_IN) { + pdata->ops->set_sysclk(pdata->adc, freq);
priv->dmic_clk = freq; + } + + /* Determine supported ratewhich depends on SPI/manchester clock */ + return stm32_adfsdm_get_supported_rates(dai, &priv->rates_const.mask);
Since the DAI is unidirectional it doesn't matter but obviously if it weren't then the fact that getting the supported rates involves setting the hwparams means this could become disruptive. If we're going to genericise this to be a more general IIO/ASoC bridge that could matter.
I think that the driver itself can not be generic. ST DFSDM is too specific. Only API with IIO could be.
+static int stm32_adfsdm_dai_remove(struct snd_soc_dai *dai) +{ + dev_dbg(dai->dev, "%s: enter for dai %d\n", __func__, dai->id); +
- return 0; +}
Remove empty functions, though in this case I think you want to add something to disconnect the XRUN callback just in order to be sure it can't be mistakenly called.
Yes Completely unnecessary here. Furthermore the driver should be removed by the IIO driver.
Regards Arnaud