[PATCH v2] PCI: qcom: Fix pipe clock imbalance

[PATCH v2] PCI: qcom: Fix pipe clock imbalance

[Johan Hovold]

Commit ed8cc3b1fc84 ("PCI: qcom: Add support for SDM845 PCIe
controller") introduced a clock imbalance by enabling the pipe clock
both in init() and in post_init() but only disabling in post_deinit().

Note that the pipe clock was also never disabled in the init() error
paths and that enabling the clock before powering up the PHY looks
questionable.

Fixes: ed8cc3b1fc84 ("PCI: qcom: Add support for SDM845 PCIe controller")
Cc: stable@vger.kernel.org      # 5.6
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---

Changes in v2
 - Capitalise "Fix" in subject line according to PCI subsystem
   convention


 drivers/pci/controller/dwc/pcie-qcom.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index b79d98e5e228..20a0e6533a1c 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1238,12 +1238,6 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
 		goto err_disable_clocks;
 	}
 
-	ret = clk_prepare_enable(res->pipe_clk);
-	if (ret) {
-		dev_err(dev, "cannot prepare/enable pipe clock\n");
-		goto err_disable_clocks;
-	}
-
 	/* Wait for reset to complete, required on SM8450 */
 	usleep_range(1000, 1500);
 
-- 
2.35.1

Re: [PATCH v2] PCI: qcom: Fix pipe clock imbalance

[Bjorn Andersson]

On Fri 01 Apr 06:33 PDT 2022, Johan Hovold wrote:

> Commit ed8cc3b1fc84 ("PCI: qcom: Add support for SDM845 PCIe
> controller") introduced a clock imbalance by enabling the pipe clock
> both in init() and in post_init() but only disabling in post_deinit().
> 
> Note that the pipe clock was also never disabled in the init() error
> paths and that enabling the clock before powering up the PHY looks
> questionable.
> 
> Fixes: ed8cc3b1fc84 ("PCI: qcom: Add support for SDM845 PCIe controller")
> Cc: stable@vger.kernel.org      # 5.6
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
> 
> Changes in v2
>  - Capitalise "Fix" in subject line according to PCI subsystem
>    convention
> 
> 
>  drivers/pci/controller/dwc/pcie-qcom.c | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index b79d98e5e228..20a0e6533a1c 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -1238,12 +1238,6 @@ static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
>  		goto err_disable_clocks;
>  	}
>  
> -	ret = clk_prepare_enable(res->pipe_clk);
> -	if (ret) {
> -		dev_err(dev, "cannot prepare/enable pipe clock\n");
> -		goto err_disable_clocks;
> -	}
> -
>  	/* Wait for reset to complete, required on SM8450 */
>  	usleep_range(1000, 1500);
>  
> -- 
> 2.35.1
> 

Re: [PATCH v2] PCI: qcom: Fix pipe clock imbalance

[Lorenzo Pieralisi]

On Fri, 1 Apr 2022 15:33:51 +0200, Johan Hovold wrote:
> Commit ed8cc3b1fc84 ("PCI: qcom: Add support for SDM845 PCIe
> controller") introduced a clock imbalance by enabling the pipe clock
> both in init() and in post_init() but only disabling in post_deinit().
> 
> Note that the pipe clock was also never disabled in the init() error
> paths and that enabling the clock before powering up the PHY looks
> questionable.
> 
> [...]

Applied to pci/qcom, thanks!

[1/1] PCI: qcom: Fix pipe clock imbalance
      https://git.kernel.org/lpieralisi/pci/c/dcd9011f59

Thanks,
Lorenzo