Re: [PATCH v3 2/2] ASoC: fsl_aud2htx: Add aud2htx module driver

Nicolin Chen
2020-11-05T01:47:38Z

On Mon, Nov 02, 2020 at 09:52:27AM +0800, Shengjiu Wang wrote:
> The AUD2HTX is a digital module that provides a bridge between
> the Audio Subsystem and the HDMI RTX Subsystem. This module
> includes intermediate storage to queue SDMA transactions prior
> to being synchronized and passed to the HDMI RTX Subsystem over
> the Audio Link.
>
> The AUD2HTX contains a DMA request routed to the SDMA module.
> This DMA request is controlled based on the watermark level in
> the 32-entry sample buffer.
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>

Despite some small comments inline.

> +static int fsl_aud2htx_dai_probe(struct snd_soc_dai *cpu_dai)
> +{
> + struct fsl_aud2htx *aud2htx = dev_get_drvdata(cpu_dai->dev);
> +
> + /* DMA request when number of entries < WTMK_LOW */
> + regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
> + AUD2HTX_CTRE_DT_MASK, 0);
> +
> + /* Disable interrupts*/
> + regmap_update_bits(aud2htx->regmap, AUD2HTX_IRQ_MASK,
> + AUD2HTX_WM_HIGH_IRQ_MASK |
> + AUD2HTX_WM_LOW_IRQ_MASK |
> + AUD2HTX_OVF_MASK,
> + AUD2HTX_WM_HIGH_IRQ_MASK |
> + AUD2HTX_WM_LOW_IRQ_MASK |
> + AUD2HTX_OVF_MASK);
> +
> + /* Configure watermark */
> + regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
> + AUD2HTX_CTRE_WL_MASK,
> + AUD2HTX_WTMK_LOW << AUD2HTX_CTRE_WL_SHIFT);
> + regmap_update_bits(aud2htx->regmap, AUD2HTX_CTRL_EXT,
> + AUD2HTX_CTRE_WH_MASK,
> + AUD2HTX_WTMK_HIGH << AUD2HTX_CTRE_WH_SHIFT);

If there isn't a hard requirement from hardware, feels better to
combine all the writes to AUD2HTX_CTRL_EXT into one single MMIO.

> +static irqreturn_t fsl_aud2htx_isr(int irq, void *dev_id)
> +{
> + return IRQ_HANDLED;

Empty isr? Perhaps can drop the request_irq() at all?

> +static int fsl_aud2htx_probe(struct platform_device *pdev)
> +{
> + struct fsl_aud2htx *aud2htx;
> + struct resource *res;
> + void __iomem *regs;
> + int ret, irq;
> +
> + aud2htx = devm_kzalloc(&pdev->dev, sizeof(*aud2htx), GFP_KERNEL);
> + if (!aud2htx)
> + return -ENOMEM;
> +
> + aud2htx->pdev = pdev;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + regs = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(regs)) {
> + dev_err(&pdev->dev, "failed ioremap\n");
> + return PTR_ERR(regs);
> + }
> +
> + aud2htx->regmap = devm_regmap_init_mmio(&pdev->dev, regs,
> + &fsl_aud2htx_regmap_config);
> + if (IS_ERR(aud2htx->regmap)) {
> + dev_err(&pdev->dev, "failed to init regmap");
> + return PTR_ERR(aud2htx->regmap);
> + }
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + dev_err(&pdev->dev, "no irq for node %s\n",
> + dev_name(&pdev->dev));

dev_err() already prints dev_name, so not necessary to print again.