Re: [PATCH v6 25/42] drm/mediatek: mtk_hdmi: Move CEC device parsing in new function

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 13/02/25 08:42, CK Hu (胡俊光) ha scritto:
> On Tue, 2025-02-11 at 12:33 +0100, AngeloGioacchino Del Regno wrote:
>> External email : Please do not click links or open attachments until you have verified the sender or the content.
>>
>>
>> Move the CEC device parsing logic to a new function called
>> mtk_hdmi_get_cec_dev(), and move the parsing action to the end
>> of mtk_hdmi_dt_parse_pdata(), allowing to remove gotos in this
>> function, reducing code size and improving readability.
>>
>> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> ---
>>   drivers/gpu/drm/mediatek/mtk_hdmi.c | 82 ++++++++++++++---------------
>>   1 file changed, 39 insertions(+), 43 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
>> index 6140b55c2830..03b56588fc7d 100644
>> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
>> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
>> @@ -1367,20 +1367,12 @@ static const struct drm_bridge_funcs mtk_hdmi_bridge_funcs = {
>>          .edid_read = mtk_hdmi_bridge_edid_read,
>>   };
>>
>> -static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>> -                                  struct platform_device *pdev)
>> +static int mtk_hdmi_get_cec_dev(struct mtk_hdmi *hdmi, struct device *dev, struct device_node *np)
>>   {
>> -       struct device *dev = &pdev->dev;
>> -       struct device_node *np = dev->of_node;
>> -       struct device_node *remote, *i2c_np;
>>          struct platform_device *cec_pdev;
>> -       struct regmap *regmap;
>> +       struct device_node *cec_np;
>>          int ret;
>>
>> -       ret = mtk_hdmi_get_all_clk(hdmi, np);
>> -       if (ret)
>> -               return dev_err_probe(dev, ret, "Failed to get clocks\n");
>> -
>>          /* The CEC module handles HDMI hotplug detection */
>>          cec_np = of_get_compatible_child(np->parent, "mediatek,mt8173-cec");
>>          if (!cec_np)
>> @@ -1394,65 +1386,69 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>>                  return -EPROBE_DEFER;
>>          }
>>          of_node_put(cec_np);
>> -       hdmi->cec_dev = &cec_pdev->dev;
>>
>>          /*
>>           * The mediatek,syscon-hdmi property contains a phandle link to the
>>           * MMSYS_CONFIG device and the register offset of the HDMI_SYS_CFG
>>           * registers it contains.
>>           */
>> -       regmap = syscon_regmap_lookup_by_phandle(np, "mediatek,syscon-hdmi");
>> -       ret = of_property_read_u32_index(np, "mediatek,syscon-hdmi", 1,
>> -                                        &hdmi->sys_offset);
>> -       if (IS_ERR(regmap))
>> -               ret = PTR_ERR(regmap);
>> -       if (ret) {
>> -               dev_err_probe(dev, ret,
>> -                             "Failed to get system configuration registers\n");
>> -               goto put_device;
>> -       }
>> -       hdmi->sys_regmap = regmap;
>> +       hdmi->sys_regmap = syscon_regmap_lookup_by_phandle(np, "mediatek,syscon-hdmi");
>> +       if (IS_ERR(hdmi->sys_regmap))
>> +               return PTR_ERR(hdmi->sys_regmap);
>> +
>> +       ret = of_property_read_u32_index(np, "mediatek,syscon-hdmi", 1, &hdmi->sys_offset);
>> +       if (ret)
>> +               return dev_err_probe(dev, ret,
>> +                                    "Failed to get system configuration registers\n");
>> +
>> +       hdmi->cec_dev = &cec_pdev->dev;
>> +       return 0;
>> +}
>> +
>> +static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi *hdmi,
>> +                                  struct platform_device *pdev)
>> +{
>> +       struct device *dev = &pdev->dev;
>> +       struct device_node *np = dev->of_node;
>> +       struct device_node *remote, *i2c_np;
>> +       int ret;
>> +
>> +       ret = mtk_hdmi_get_all_clk(hdmi, np);
>> +       if (ret)
>> +               return dev_err_probe(dev, ret, "Failed to get clocks\n");
>>
>>          hdmi->regs = device_node_to_regmap(dev->of_node);
>> -       if (IS_ERR(hdmi->regs)) {
>> -               ret = PTR_ERR(hdmi->regs);
>> -               goto put_device;
>> -       }
>> +       if (IS_ERR(hdmi->regs))
>> +               return PTR_ERR(hdmi->regs);
>>
>>          remote = of_graph_get_remote_node(np, 1, 0);
>> -       if (!remote) {
>> -               ret = -EINVAL;
>> -               goto put_device;
>> -       }
>> +       if (!remote)
>> +               return -EINVAL;
>>
>>          if (!of_device_is_compatible(remote, "hdmi-connector")) {
>>                  hdmi->next_bridge = of_drm_find_bridge(remote);
>>                  if (!hdmi->next_bridge) {
>>                          dev_err(dev, "Waiting for external bridge\n");
>>                          of_node_put(remote);
>> -                       ret = -EPROBE_DEFER;
>> -                       goto put_device;
>> +                       return -EPROBE_DEFER;
>>                  }
>>          }
>>
>>          i2c_np = of_parse_phandle(remote, "ddc-i2c-bus", 0);
>>          of_node_put(remote);
>> -       if (!i2c_np) {
>> -               ret = dev_err_probe(dev, -EINVAL, "No ddc-i2c-bus in connector\n");
>> -               goto put_device;
>> -       }
>> +       if (!i2c_np)
>> +               return dev_err_probe(dev, -EINVAL, "No ddc-i2c-bus in connector\n");
>>
>>          hdmi->ddc_adpt = of_find_i2c_adapter_by_node(i2c_np);
>>          of_node_put(i2c_np);
>> -       if (!hdmi->ddc_adpt) {
>> -               ret = dev_err_probe(dev, -EINVAL, "Failed to get ddc i2c adapter by node\n");
>> -               goto put_device;
>> -       }
>> +       if (!hdmi->ddc_adpt)
>> +               return dev_err_probe(dev, -EINVAL, "Failed to get ddc i2c adapter by node\n");
>> +
>> +       ret = mtk_hdmi_get_cec_dev(hdmi, dev, np);
>> +       if (ret)
>> +               return ret;
>>
>>          return 0;
> 
> return mtk_hdmi_get_cec_dev(hdmi, dev, np);
> 
> or
> 
> ret = mtk_hdmi_get_cec_dev(hdmi, dev, np);
> 
> return ret;
> 
> After this,
> 
> Reviewed-by: CK Hu <ck.hu@mediatek.com>
> 

Can we please avoid this change?

That's done so that any addition to the end of the function produces a smaller diff
and for return value readability.

Thanks,
Angelo

>> -put_device:
>> -       put_device(hdmi->cec_dev);
>> -       return ret;
>>   }
>>
>>   /*
>> --
>> 2.48.1
>>
>