[v4,1/5] PCI: qcom: Remove unnecessary pipe_clk handling

QMP PHY driver already does clk_prepare_enable()/_disable() pipe_clk.
Remove extra calls to enable/disable this clock from the PCIe driver, so
that the PHY driver can manage the clock on its own.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/pci/controller/dwc/pcie-qcom.c | 44 ++------------------------
 1 file changed, 3 insertions(+), 41 deletions(-)

On Sun, May 01, 2022 at 10:21:45PM +0300, Dmitry Baryshkov wrote:
> QMP PHY driver already does clk_prepare_enable()/_disable() pipe_clk.
> Remove extra calls to enable/disable this clock from the PCIe driver, so
> that the PHY driver can manage the clock on its own.
> 
> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thanks,
Mani

> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 44 ++------------------------
>  1 file changed, 3 insertions(+), 41 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 57636246cecc..a6becafb6a77 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -128,7 +128,6 @@ struct qcom_pcie_resources_2_3_2 {
>  	struct clk *master_clk;
>  	struct clk *slave_clk;
>  	struct clk *cfg_clk;
> -	struct clk *pipe_clk;
>  	struct regulator_bulk_data supplies[QCOM_PCIE_2_3_2_MAX_SUPPLY];
>  };
>  
> @@ -165,7 +164,6 @@ struct qcom_pcie_resources_2_7_0 {
>  	int num_clks;
>  	struct regulator_bulk_data supplies[2];
>  	struct reset_control *pci_reset;
> -	struct clk *pipe_clk;
>  	struct clk *pipe_clk_src;
>  	struct clk *phy_pipe_clk;
>  	struct clk *ref_clk_src;
> @@ -597,8 +595,7 @@ static int qcom_pcie_get_resources_2_3_2(struct qcom_pcie *pcie)
>  	if (IS_ERR(res->slave_clk))
>  		return PTR_ERR(res->slave_clk);
>  
> -	res->pipe_clk = devm_clk_get(dev, "pipe");
> -	return PTR_ERR_OR_ZERO(res->pipe_clk);
> +	return 0;
>  }
>  
>  static void qcom_pcie_deinit_2_3_2(struct qcom_pcie *pcie)
> @@ -613,13 +610,6 @@ static void qcom_pcie_deinit_2_3_2(struct qcom_pcie *pcie)
>  	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
>  }
>  
> -static void qcom_pcie_post_deinit_2_3_2(struct qcom_pcie *pcie)
> -{
> -	struct qcom_pcie_resources_2_3_2 *res = &pcie->res.v2_3_2;
> -
> -	clk_disable_unprepare(res->pipe_clk);
> -}
> -
>  static int qcom_pcie_init_2_3_2(struct qcom_pcie *pcie)
>  {
>  	struct qcom_pcie_resources_2_3_2 *res = &pcie->res.v2_3_2;
> @@ -694,22 +684,6 @@ static int qcom_pcie_init_2_3_2(struct qcom_pcie *pcie)
>  	return ret;
>  }
>  
> -static int qcom_pcie_post_init_2_3_2(struct qcom_pcie *pcie)
> -{
> -	struct qcom_pcie_resources_2_3_2 *res = &pcie->res.v2_3_2;
> -	struct dw_pcie *pci = pcie->pci;
> -	struct device *dev = pci->dev;
> -	int ret;
> -
> -	ret = clk_prepare_enable(res->pipe_clk);
> -	if (ret) {
> -		dev_err(dev, "cannot prepare/enable pipe clock\n");
> -		return ret;
> -	}
> -
> -	return 0;
> -}
> -
>  static int qcom_pcie_get_resources_2_4_0(struct qcom_pcie *pcie)
>  {
>  	struct qcom_pcie_resources_2_4_0 *res = &pcie->res.v2_4_0;
> @@ -1198,8 +1172,7 @@ static int qcom_pcie_get_resources_2_7_0(struct qcom_pcie *pcie)
>  			return PTR_ERR(res->ref_clk_src);
>  	}
>  
> -	res->pipe_clk = devm_clk_get(dev, "pipe");
> -	return PTR_ERR_OR_ZERO(res->pipe_clk);
> +	return 0;
>  }
>  
>  static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
> @@ -1292,14 +1265,7 @@ static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
>  	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);
> -}
> -
> -static void qcom_pcie_post_deinit_2_7_0(struct qcom_pcie *pcie)
> -{
> -	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
> -
> -	clk_disable_unprepare(res->pipe_clk);
> +	return 0;
>  }
>  
>  static int qcom_pcie_link_up(struct dw_pcie *pci)
> @@ -1449,9 +1415,7 @@ static const struct qcom_pcie_ops ops_1_0_0 = {
>  static const struct qcom_pcie_ops ops_2_3_2 = {
>  	.get_resources = qcom_pcie_get_resources_2_3_2,
>  	.init = qcom_pcie_init_2_3_2,
> -	.post_init = qcom_pcie_post_init_2_3_2,
>  	.deinit = qcom_pcie_deinit_2_3_2,
> -	.post_deinit = qcom_pcie_post_deinit_2_3_2,
>  	.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
>  };
>  
> @@ -1478,7 +1442,6 @@ static const struct qcom_pcie_ops ops_2_7_0 = {
>  	.deinit = qcom_pcie_deinit_2_7_0,
>  	.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
>  	.post_init = qcom_pcie_post_init_2_7_0,
> -	.post_deinit = qcom_pcie_post_deinit_2_7_0,
>  };
>  
>  /* Qcom IP rev.: 1.9.0 */
> @@ -1488,7 +1451,6 @@ static const struct qcom_pcie_ops ops_1_9_0 = {
>  	.deinit = qcom_pcie_deinit_2_7_0,
>  	.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
>  	.post_init = qcom_pcie_post_init_2_7_0,
> -	.post_deinit = qcom_pcie_post_deinit_2_7_0,
>  	.config_sid = qcom_pcie_config_sid_sm8250,
>  };
>  
> -- 
> 2.35.1
>

On Sun, May 01, 2022 at 10:21:45PM +0300, Dmitry Baryshkov wrote:
> QMP PHY driver already does clk_prepare_enable()/_disable() pipe_clk.

The pcie-qcom driver is used also with non-QMP PHYs such as the Qualcomm
PCIe2 PHY so please expand the commit message here explaining why this
is safe to remove.

> Remove extra calls to enable/disable this clock from the PCIe driver, so
> that the PHY driver can manage the clock on its own.

Johan