Re: [PATCH v1 04/10] PCI: qcom: do not duplicate qcom_pcie_cfg fields in qcom_pcie struct

[Bjorn Helgaas <helgaas@kernel.org>]

On Thu, Dec 02, 2021 at 05:17:20PM +0300, Dmitry Baryshkov wrote:
> In preparation to adding more flags to configuration data, use struct
> qcom_pcie_cfg directly inside struct qcom_pcie, rather than duplicating
> all its fields. This would save us from the boilerplate code that just
> copies flags values from one sruct to another one.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 34 ++++++++++++--------------
>  1 file changed, 16 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 3bee901c4df7..64f762cdbc7d 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -204,8 +204,7 @@ struct qcom_pcie {
>  	union qcom_pcie_resources res;
>  	struct phy *phy;
>  	struct gpio_desc *reset;
> -	const struct qcom_pcie_ops *ops;
> -	unsigned int pipe_clk_need_muxing:1;
> +	struct qcom_pcie_cfg cfg;

A common strategy is to simply save the pointer to the match data,
e.g.,

    struct imx6_pcie {
      ...
      const struct imx6_pcie_drvdata *drvdata;
    };

    imx6_pcie_probe()
      imx6_pcie->drvdata = of_device_get_match_data(dev);
    

    struct ls_pcie {
      ...
      const struct ls_pcie_drvdata *drvdata;
    };

    ls_pcie_probe()
      pcie->drvdata = of_device_get_match_data(dev);
    
    
    struct tegra_pcie {
      ...
      const struct tegra_pcie_soc *soc;
    };

    tegra_pcie_probe()
      pcie->soc = of_device_get_match_data(dev);
    

    struct mtk_pcie {
      ...
      const struct mtk_pcie_soc *soc;
    };

    mtk_pcie_probe()
      pcie->soc = of_device_get_match_data(dev);

Bonus points if you name the pointer the same, e.g., "soc" or maybe
"drvdata" (although this one is possibly confusing with
platform_set_drvdata(), which is something different).

>  };
>  
>  #define to_qcom_pcie(x)		dev_get_drvdata((x)->dev)
> @@ -229,8 +228,8 @@ static int qcom_pcie_start_link(struct dw_pcie *pci)
>  	struct qcom_pcie *pcie = to_qcom_pcie(pci);
>  
>  	/* Enable Link Training state machine */
> -	if (pcie->ops->ltssm_enable)
> -		pcie->ops->ltssm_enable(pcie);
> +	if (pcie->cfg.ops->ltssm_enable)
> +		pcie->cfg.ops->ltssm_enable(pcie);
>  
>  	return 0;
>  }
> @@ -1176,7 +1175,7 @@ static int qcom_pcie_get_resources_2_7_0(struct qcom_pcie *pcie)
>  	if (ret < 0)
>  		return ret;
>  
> -	if (pcie->pipe_clk_need_muxing) {
> +	if (pcie->cfg.pipe_clk_need_muxing) {
>  		res->pipe_clk_src = devm_clk_get(dev, "pipe_mux");
>  		if (IS_ERR(res->pipe_clk_src))
>  			return PTR_ERR(res->pipe_clk_src);
> @@ -1209,7 +1208,7 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
>  	}
>  
>  	/* Set TCXO as clock source for pcie_pipe_clk_src */
> -	if (pcie->pipe_clk_need_muxing)
> +	if (pcie->cfg.pipe_clk_need_muxing)
>  		clk_set_parent(res->pipe_clk_src, res->ref_clk_src);
>  
>  	ret = clk_bulk_prepare_enable(res->num_clks, res->clks);
> @@ -1287,7 +1286,7 @@ static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
>  	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
>  
>  	/* Set pipe clock as clock source for pcie_pipe_clk_src */
> -	if (pcie->pipe_clk_need_muxing)
> +	if (pcie->cfg.pipe_clk_need_muxing)
>  		clk_set_parent(res->pipe_clk_src, res->phy_pipe_clk);
>  
>  	return clk_prepare_enable(res->pipe_clk);
> @@ -1387,7 +1386,7 @@ static int qcom_pcie_host_init(struct pcie_port *pp)
>  
>  	qcom_ep_reset_assert(pcie);
>  
> -	ret = pcie->ops->init(pcie);
> +	ret = pcie->cfg.ops->init(pcie);
>  	if (ret)
>  		return ret;
>  
> @@ -1395,16 +1394,16 @@ static int qcom_pcie_host_init(struct pcie_port *pp)
>  	if (ret)
>  		goto err_deinit;
>  
> -	if (pcie->ops->post_init) {
> -		ret = pcie->ops->post_init(pcie);
> +	if (pcie->cfg.ops->post_init) {
> +		ret = pcie->cfg.ops->post_init(pcie);
>  		if (ret)
>  			goto err_disable_phy;
>  	}
>  
>  	qcom_ep_reset_deassert(pcie);
>  
> -	if (pcie->ops->config_sid) {
> -		ret = pcie->ops->config_sid(pcie);
> +	if (pcie->cfg.ops->config_sid) {
> +		ret = pcie->cfg.ops->config_sid(pcie);
>  		if (ret)
>  			goto err;
>  	}
> @@ -1413,12 +1412,12 @@ static int qcom_pcie_host_init(struct pcie_port *pp)
>  
>  err:
>  	qcom_ep_reset_assert(pcie);
> -	if (pcie->ops->post_deinit)
> -		pcie->ops->post_deinit(pcie);
> +	if (pcie->cfg.ops->post_deinit)
> +		pcie->cfg.ops->post_deinit(pcie);
>  err_disable_phy:
>  	phy_power_off(pcie->phy);
>  err_deinit:
> -	pcie->ops->deinit(pcie);
> +	pcie->cfg.ops->deinit(pcie);
>  
>  	return ret;
>  }
> @@ -1562,8 +1561,7 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	pcie->ops = pcie_cfg->ops;
> -	pcie->pipe_clk_need_muxing = pcie_cfg->pipe_clk_need_muxing;
> +	pcie->cfg = *pcie_cfg;
>  
>  	pcie->reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
>  	if (IS_ERR(pcie->reset)) {
> @@ -1589,7 +1587,7 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  		goto err_pm_runtime_put;
>  	}
>  
> -	ret = pcie->ops->get_resources(pcie);
> +	ret = pcie->cfg.ops->get_resources(pcie);
>  	if (ret)
>  		goto err_pm_runtime_put;
>  
> -- 
> 2.33.0
>