Re: [PATCH v3 8/9] media: chips-media: wave6: Add Wave6 control driver

[Krzysztof Kozlowski <krzk@kernel.org>]

On 29/08/2025 10:46, Nas Chung wrote:
> +
> +static void wave6_vpu_load_firmware(const struct firmware *fw, void *context)
> +{
> +	struct wave6_vpu_device *vpu = context;
> +
> +	guard(mutex)(&vpu->lock);

Why? How could this be called in parallel, before the probe?

> +
> +	if (!fw || !fw->data) {
> +		dev_err(vpu->dev, "No firmware.\n");
> +		return;
> +	}
> +
> +	if (!vpu->fw_available)
> +		goto exit;
> +
> +	if (fw->size + W6_EXTRA_CODE_BUF_SIZE > wave6_vpu_get_code_buf_size(vpu)) {
> +		dev_err(vpu->dev, "firmware size (%ld > %zd) is too big\n",
> +			fw->size, vpu->code_buf.size);
> +		vpu->fw_available = false;
> +		goto exit;
> +	}
> +
> +	memcpy(vpu->code_buf.vaddr, fw->data, fw->size);
> +
> +	vpu->get_vpu = wave6_vpu_get;
> +	vpu->put_vpu = wave6_vpu_put;
> +	vpu->req_work_buffer = wave6_vpu_require_work_buffer;
> +	of_platform_populate(vpu->dev->of_node, NULL, NULL, vpu->dev);
> +
> +exit:
> +	release_firmware(fw);
> +}
> +
> +static int wave6_vpu_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np;
> +	struct wave6_vpu_device *vpu;
> +	const struct wave6_vpu_resource *res;
> +	int ret;
> +
> +	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "dma_set_mask_and_coherent failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	res = of_device_get_match_data(&pdev->dev);
> +	if (!res)
> +		return -ENODEV;
> +
> +	vpu = devm_kzalloc(&pdev->dev, sizeof(*vpu), GFP_KERNEL);
> +	if (!vpu)
> +		return -ENOMEM;
> +
> +	ret = devm_mutex_init(&pdev->dev, &vpu->lock);
> +	if (ret)
> +		return ret;
> +
> +	atomic_set(&vpu->core_count, 0);
> +	INIT_LIST_HEAD(&vpu->work_buffers);
> +	dev_set_drvdata(&pdev->dev, vpu);
> +	vpu->dev = &pdev->dev;
> +	vpu->res = res;
> +	vpu->reg_base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(vpu->reg_base))
> +		return PTR_ERR(vpu->reg_base);
> +
> +	ret = devm_clk_bulk_get_all(&pdev->dev, &vpu->clks);
> +	if (ret < 0) {
> +		dev_warn(&pdev->dev, "unable to get clocks: %d\n", ret);

You need to handle deferred probe.

> +		ret = 0;
> +	}
> +	vpu->num_clks = ret;
Best regards,
Krzysztof