Re: [PATCH V4 6/6] spi: mediatek: support hclk

[AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>]

Il 15/03/22 04:24, Leilk Liu ha scritto:
> this patch adds hclk support.
>
> Signed-off-by: Leilk Liu <leilk.liu@xxxxxxxxxxxx>
> ---
>   drivers/spi/spi-mt65xx.c | 85 ++++++++++++++++++++++++++++++++--------
>   1 file changed, 69 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
> index 8958c3fa4fea..d4a602e78aa7 100644
> --- a/drivers/spi/spi-mt65xx.c
> +++ b/drivers/spi/spi-mt65xx.c
> @@ -130,7 +130,7 @@ struct mtk_spi {
>   	u32 state;
>   	int pad_num;
>   	u32 *pad_sel;
> -	struct clk *parent_clk, *sel_clk, *spi_clk;
> +	struct clk *parent_clk, *sel_clk, *spi_clk, *spi_hclk;
>   	struct spi_transfer *cur_transfer;
>   	u32 xfer_len;
>   	u32 num_xfered;
> @@ -1252,25 +1252,38 @@ static int mtk_spi_probe(struct platform_device *pdev)
>   		goto err_put_master;
>   	}
>   
> +	mdata->spi_hclk = devm_clk_get(&pdev->dev, "hclk");
> +	if (!IS_ERR(mdata->spi_hclk)) {

What you're doing here can be simplified by using devm_clk_get_optional() instead.
Please use that.

> +		ret = clk_prepare_enable(mdata->spi_hclk);
> +		if (ret < 0) {
> +			dev_err(&pdev->dev, "failed to enable hclk (%d)\n", ret);
> +			goto err_put_master;
> +		}
> +	}
> +
>   	ret = clk_prepare_enable(mdata->spi_clk);
>   	if (ret < 0) {
>   		dev_err(&pdev->dev, "failed to enable spi_clk (%d)\n", ret);
> -		goto err_put_master;
> +		goto err_disable_spi_hclk;
>   	}
>   
>   	ret = clk_set_parent(mdata->sel_clk, mdata->parent_clk);
>   	if (ret < 0) {
>   		dev_err(&pdev->dev, "failed to clk_set_parent (%d)\n", ret);
> -		clk_disable_unprepare(mdata->spi_clk);
> -		goto err_put_master;
> +		goto err_disable_spi_clk;
>   	}
>   
>   	mdata->spi_clk_hz = clk_get_rate(mdata->spi_clk);
>   
> -	if (mdata->dev_comp->no_need_unprepare)
> +	if (mdata->dev_comp->no_need_unprepare) {
>   		clk_disable(mdata->spi_clk);
> -	else
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_disable(mdata->spi_hclk);
> +	} else {
>   		clk_disable_unprepare(mdata->spi_clk);
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_disable_unprepare(mdata->spi_hclk);
> +	}
>   
>   	pm_runtime_enable(&pdev->dev);
>   
> @@ -1310,6 +1323,11 @@ static int mtk_spi_probe(struct platform_device *pdev)
>   
>   err_disable_runtime_pm:
>   	pm_runtime_disable(&pdev->dev);
> +err_disable_spi_clk:
> +	clk_disable_unprepare(mdata->spi_clk);
> +err_disable_spi_hclk:
> +	if (!IS_ERR(mdata->spi_hclk))

When using devm_clk_get_optional(), you can simply omit this check, since it will
be impossible to reach this point with an error pointer stored in spi_hclk.

> +		clk_disable_unprepare(mdata->spi_hclk);
>   err_put_master:
>   	spi_master_put(master);
>   
> @@ -1325,8 +1343,11 @@ static int mtk_spi_remove(struct platform_device *pdev)
>   
>   	mtk_spi_reset(mdata);
>   
> -	if (mdata->dev_comp->no_need_unprepare)
> +	if (mdata->dev_comp->no_need_unprepare) {
>   		clk_unprepare(mdata->spi_clk);
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_unprepare(mdata->spi_hclk);
> +	}
>   
>   	return 0;
>   }
> @@ -1342,8 +1363,11 @@ static int mtk_spi_suspend(struct device *dev)
>   	if (ret)
>   		return ret;
>   
> -	if (!pm_runtime_suspended(dev))
> +	if (!pm_runtime_suspended(dev)) {
>   		clk_disable_unprepare(mdata->spi_clk);
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_disable_unprepare(mdata->spi_hclk);
> +	}
>   
>   	return ret;
>   }
> @@ -1360,11 +1384,23 @@ static int mtk_spi_resume(struct device *dev)
>   			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
>   			return ret;
>   		}
> +
> +		if (!IS_ERR(mdata->spi_hclk)) {

Since you will be using devm_clk_get_optional(), you can also omit this check.

> +			clk_prepare_enable(mdata->spi_hclk);

There's a typo. ret = clk_prepare_enable....

> +			if (ret < 0) {
> +				dev_err(dev, "failed to enable spi_hclk (%d)\n", ret);
> +				clk_disable_unprepare(mdata->spi_clk);
> +				return ret;
> +			}
> +		}
>   	}
>   
>   	ret = spi_master_resume(master);
> -	if (ret < 0)
> +	if (ret < 0) {
>   		clk_disable_unprepare(mdata->spi_clk);
> +		if (!IS_ERR(mdata->spi_hclk))

Same here and everywhere else, no error check if you set this as optional clock.

> +			clk_disable_unprepare(mdata->spi_hclk);
> +	}
>   
>   	return ret;
>   }
> @@ -1376,10 +1412,15 @@ static int mtk_spi_runtime_suspend(struct device *dev)
>   	struct spi_master *master = dev_get_drvdata(dev);
>   	struct mtk_spi *mdata = spi_master_get_devdata(master);
>   
> -	if (mdata->dev_comp->no_need_unprepare)
> +	if (mdata->dev_comp->no_need_unprepare) {
>   		clk_disable(mdata->spi_clk);
> -	else
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_disable(mdata->spi_hclk);
> +	} else {
>   		clk_disable_unprepare(mdata->spi_clk);
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_disable_unprepare(mdata->spi_hclk);
> +	}
>   
>   	return 0;
>   }
> @@ -1390,13 +1431,25 @@ static int mtk_spi_runtime_resume(struct device *dev)
>   	struct mtk_spi *mdata = spi_master_get_devdata(master);
>   	int ret;
>   
> -	if (mdata->dev_comp->no_need_unprepare)
> +	if (mdata->dev_comp->no_need_unprepare) {
>   		ret = clk_enable(mdata->spi_clk);
> -	else
> +		if (!IS_ERR(mdata->spi_hclk))
> +			clk_enable(mdata->spi_hclk);
> +	} else {
>   		ret = clk_prepare_enable(mdata->spi_clk);
> -	if (ret < 0) {
> -		dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
> -		return ret;
> +		if (ret < 0) {
> +			dev_err(dev, "failed to enable spi_clk (%d)\n", ret);
> +			return ret;
> +		}
> +
> +		if (!IS_ERR(mdata->spi_hclk)) {
> +			ret = clk_prepare_enable(mdata->spi_hclk);
> +			if (ret < 0) {
> +				dev_err(dev, "failed to enable spi_hclk (%d)\n", ret);
> +				clk_disable_unprepare(mdata->spi_clk);
> +				return ret;
> +			}
> +		}
>   	}
>   
>   	return 0;


Regards,
Angelo