Re: [TEMP PATCH 16/17] pci: host: pcie-dra7xx: use reset framework APIs to reset PCIe

Dan Murphy
2014-05-06T13:41:39Z

On 05/06/2014 08:34 AM, Kishon Vijay Abraham I wrote:
> Get reset nodes from dt and use reset framework APIs to reset PCIe.
> This is needed since reset is handled by the SoC.
>
> Cc: Dan Murphy <dmurphy@ti.com>
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
> Documentation/devicetree/bindings/pci/ti-pci.txt | 2 ++
> drivers/pci/host/pci-dra7xx.c | 10 ++++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pci/ti-pci.txt b/Documentation/devicetree/bindings/pci/ti-pci.txt
> index 6cb6f09..cfb95c0 100644
> --- a/Documentation/devicetree/bindings/pci/ti-pci.txt
> +++ b/Documentation/devicetree/bindings/pci/ti-pci.txt
> @@ -9,6 +9,8 @@ This node should have the properties described in "designware-pcie.txt".
> - phys : the phandle for the PHY device (used by generic PHY framework)
> - phy-names : the names of the PHY corresponding to the PHYs present in the
> *phy* phandle.
> + - resets: phandle used if reset is handled be soc
> + - reset-names: name given to the phandle

You should just refer to the ti,reset.txt document for this.

>
> Example:
> pcie@51000000 {
> diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
> index a37c25c..17d64ee 100644
> --- a/drivers/pci/host/pci-dra7xx.c
> +++ b/drivers/pci/host/pci-dra7xx.c
> @@ -20,6 +20,7 @@
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> #include <linux/resource.h>
> +#include <linux/reset.h>
> #include <linux/types.h>
>
> #include "pcie-designware.h"
> @@ -281,6 +282,7 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev)
> struct resource *res;
> struct dra7xx_pcie *dra7xx;
> struct device *dev = &pdev->dev;
> + struct reset_control *rstc;
>
> dra7xx = devm_kzalloc(&pdev->dev, sizeof(*dra7xx), GFP_KERNEL);
> if (!dra7xx)
> @@ -304,6 +306,14 @@ static int __init dra7xx_pcie_probe(struct platform_device *pdev)
> if (!base)
> return -ENOMEM;
>
> + rstc = devm_reset_control_get(dev, "reset");
> + if (IS_ERR(rstc))
> + return PTR_ERR(rstc);
> +
> + ret = reset_control_deassert(rstc);
> + if (ret)
> + return ret;
> +
> phy = devm_phy_get(dev, "pcie-phy");
> if (IS_ERR(phy))
> return PTR_ERR(phy);

--
------------------
Dan Murphy