On Fri, Nov 27, 2020 at 01:30:21PM +0800, Shengjiu Wang wrote:
> The driver is initially designed for sound card using HDMI
> interface on i.MX platform. There is internal HDMI IP or
> external HDMI modules connect with SAI or AUD2HTX interface.
> It supports both transmitter and receiver devices.
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> ---
> sound/soc/fsl/Kconfig | 12 ++
> sound/soc/fsl/Makefile | 2 +
> sound/soc/fsl/imx-hdmi.c | 235 +++++++++++++++++++++++++++++++++++++++
> 3 files changed, 249 insertions(+)
> create mode 100644 sound/soc/fsl/imx-hdmi.c
> diff --git a/sound/soc/fsl/imx-hdmi.c b/sound/soc/fsl/imx-hdmi.c
> new file mode 100644
> index 000000000000..ac164514b1b2
> --- /dev/null
> +++ b/sound/soc/fsl/imx-hdmi.c
> +static int imx_hdmi_hw_params(struct snd_pcm_substream *substream,
> + struct snd_pcm_hw_params *params)
> +{
> + struct snd_soc_pcm_runtime *rtd = substream->private_data;
> + struct imx_hdmi_data *data = snd_soc_card_get_drvdata(rtd->card);
> + bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
> + struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
> + struct snd_soc_card *card = rtd->card;
> + struct device *dev = card->dev;
> + int ret;
> +
> + /* set cpu DAI configuration */
> + ret = snd_soc_dai_set_sysclk(cpu_dai, data->cpu_priv.sysclk_id[tx],
> + 8 * data->cpu_priv.slot_width * params_rate(params),
Looks like fixed 2 slots being used, judging by the set_tdm_slot
call below. Then...why "8 *"? Probably need a line of comments?
> + tx ? SND_SOC_CLOCK_OUT : SND_SOC_CLOCK_IN);
> + if (ret && ret != -ENOTSUPP) {
> + dev_err(dev, "failed to set cpu sysclk: %d\n", ret);
> + return ret;
> + }
> +
> + ret = snd_soc_dai_set_tdm_slot(cpu_dai, 0, 0, 2, data->cpu_priv.slot_width);
May have a local variable to cache slot_width.
> +static int imx_hdmi_probe(struct platform_device *pdev)
> + data->dai.name = "i.MX HDMI";
> + data->dai.stream_name = "i.MX HDMI";
> + data->dai.cpus->dai_name = dev_name(&cpu_pdev->dev);
> + data->dai.platforms->of_node = cpu_np;
> + data->dai.ops = &imx_hdmi_ops;
> + data->dai.playback_only = true;
> + data->dai.capture_only = false;
> + data->dai.init = imx_hdmi_init;
> +
> +
> + if (of_property_read_bool(np, "hdmi-out")) {
> + data->dai.playback_only = true;
> + data->dai.capture_only = false;
> + data->dai.codecs->dai_name = "i2s-hifi";
> + data->dai.codecs->name = "hdmi-audio-codec.1";
> + data->dai.dai_fmt = data->dai_fmt |
> + SND_SOC_DAIFMT_NB_NF |
> + SND_SOC_DAIFMT_CBS_CFS;
> + }
> +
> + if (of_property_read_bool(np, "hdmi-in")) {
> + data->dai.playback_only = false;
> + data->dai.capture_only = true;
> + data->dai.codecs->dai_name = "i2s-hifi";
> + data->dai.codecs->name = "hdmi-audio-codec.2";
> + data->dai.dai_fmt = data->dai_fmt |
> + SND_SOC_DAIFMT_NB_NF |
> + SND_SOC_DAIFMT_CBM_CFM;
> + }
> +
> + if ((data->dai.playback_only && data->dai.capture_only) ||
> + (!data->dai.playback_only && !data->dai.capture_only)) {
> + dev_err(&pdev->dev, "Wrongly enable HDMI DAI link\n");
> + goto fail;
> + }
Seems that this condition check can never be true, given that:
1. By default: playback_only=true && capture_only=false
2. Conditionally overwritten: playback_only=true && capture_only=false
3. Conditionally overwritten: playback_only=false && capture_only=true
If I understand it correctly, probably should be something like:
bool hdmi_out = of_property_read_bool(np, "hdmi-out");
bool hdmi_in = of_property_read_bool(np, "hdmi-in");
if ((hdmi_out && hdmi_in) || (!hdmi_out || !hdmi_in))
// "Invalid HDMI DAI link"; goto fail;
if (hdmi_out) {
// ...
} else if (hdmi_in) {
// ...
} else // No need of this line if two properties are exclusive
> + data->card.num_links = 1;
> + data->card.dai_link = &data->dai;
> +
> + platform_set_drvdata(pdev, &data->card);
Why pass card pointer?
