Re: [PATCH v5 2/2] memory: mtk-smi: mt8188: Add SMI reset and clamp for MT8188

On Wed, 2025-03-12 at 13:02 +0100, Krzysztof Kozlowski wrote:

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On 11/03/2025 13:23, Friday Yang wrote:

quoted

 static int mtk_smi_device_link_common(struct device *dev, struct
device **com_dev)
 {
      struct platform_device *smi_com_pdev;

@@ -528,6 +598,53 @@ static int mtk_smi_dts_clk_init(struct device

*dev, struct mtk_smi *smi,
      return ret;
 }

+static int mtk_smi_larb_parse_clamp_optional(struct mtk_smi_larb
*larb)
+{
+     struct device *dev = larb->dev;
+     const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
+     u32 larb_id;
+     int ret;
+
+     /**

Not a kerneldoc

OK, I will fix it like this:
/*
 * Only SMI LARBs ...
 */

quoted

+      * Only SMI LARBs in camera, image and IPE subsys need to
+      * apply clamp and reset operations, others can be skipped.
+      */
+     ret = of_property_read_u32(dev->of_node, "mediatek,larb-id",
&larb_id);

...

quoted

 static const struct mtk_smi_common_plat mtk_smi_common_mt8192 = {
      .type     = MTK_SMI_GEN2,
      .has_gals = true,

@@ -729,6 +862,7 @@ static const struct of_device_id

mtk_smi_common_of_ids[] = {
      {.compatible = "mediatek,mt8186-smi-common", .data =
&mtk_smi_common_mt8186},
      {.compatible = "mediatek,mt8188-smi-common-vdo", .data =
&mtk_smi_common_mt8188_vdo},
      {.compatible = "mediatek,mt8188-smi-common-vpp", .data =
&mtk_smi_common_mt8188_vpp},
+     {.compatible = "mediatek,mt8188-smi-sub-common", .data =
&mtk_smi_sub_common_mt8188},
      {.compatible = "mediatek,mt8192-smi-common", .data =
&mtk_smi_common_mt8192},
      {.compatible = "mediatek,mt8195-smi-common-vdo", .data =
&mtk_smi_common_mt8195_vdo},
      {.compatible = "mediatek,mt8195-smi-common-vpp", .data =
&mtk_smi_common_mt8195_vpp},

@@ -787,7 +921,10 @@ static int mtk_smi_common_probe(struct

platform_device *pdev)
                      return ret;
      }

-     pm_runtime_enable(dev);
+     ret = devm_pm_runtime_enable(dev);
+     if (ret)
+             return ret;
+
      platform_set_drvdata(pdev, common);
      return 0;
 }

@@ -798,7 +935,6 @@ static void mtk_smi_common_remove(struct

platform_device *pdev)

      if (common->plat->type == MTK_SMI_GEN2_SUB_COMM)
              device_link_remove(&pdev->dev, common-

quoted

smi_common_dev);

-     pm_runtime_disable(&pdev->dev);

Does not look related to this patch. Is it some sort of cleanup to
devm?

This 'devm' modification aims to remove 'pm_runtime_disable' and
'err_pm_disable', which would make the code more efficient. 
If I insist on using 'pm_runtime_enable', I would need to add another
'goto err_pm_disable', which is not an ideal solution. Just as below,

	ret = mtk_smi_larb_parse_clamp_optional(larb);
	if (ret)
		goto err_link_remove;

	ret = mtk_smi_larb_parse_reset_optional(larb);
	if (ret)
		goto err_link_remove;

	pm_runtime_enable(dev);
	platform_set_drvdata(pdev, larb);
	ret = component_add(dev, &mtk_smi_larb_component_ops);
	if (ret)
		goto err_pm_disable;

	return 0;

err_pm_disable:
	pm_runtime_disable(dev);
err_link_remove:
	device_link_remove(dev, larb->smi_common_dev);
	return ret;

Therefore, I prefer to use 'devm_pm_runtime_enable' here. Please let me
know if you have any concerns, thanks!

Best regards,
Krzysztof