Re: [RESEND PATCH v4 2/3] mmc: sdhci-of-arasan: add phy support for sdhci-of-arasan

[Ulf Hansson]

On 22 October 2015 at 11:06, Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> wrote:
> This patch adds Generic PHY access for sdhci-of-arasan. Driver
> can get PHY handler from dt-binding, and power-on/init the PHY.
> Also we add pm ops for PHY here if CONFIG_PM_SLEEP is enabled.
> Currently, it's just mandatory for arasan,sdhci-5.1.
>
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
>
> Serise-changes: 4
> - remove suspend/resume_phy
> - add err handle label for system PM callback
> - fix comments of struct sdhci_arasan_data and system PM
>   callback suggested by Michal
>
> Serise-changes: 3
> - remove phy_init/exit for suspend/resume
> - adjust phy_int/power_on seq to make code more reasonable
> - simplify suspend/resume_phy
>
> Serise-changes: 2
> - Keep phy as a mandatory requirement for arasan,sdhci-5.1
>
> ---
>
> Changes in v2: None
>
>  drivers/mmc/host/sdhci-of-arasan.c | 63 +++++++++++++++++++++++++++++++++++---
>  1 file changed, 59 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index 75379cb..4f30716 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -21,6 +21,7 @@
>
>  #include <linux/module.h>
>  #include <linux/of_device.h>
> +#include <linux/phy/phy.h>
>  #include "sdhci-pltfm.h"
>
>  #define SDHCI_ARASAN_CLK_CTRL_OFFSET   0x2c
> @@ -32,9 +33,11 @@
>  /**
>   * struct sdhci_arasan_data
>   * @clk_ahb:   Pointer to the AHB clock
> + * @phy: Pointer to the generic phy
>   */
>  struct sdhci_arasan_data {
>         struct clk      *clk_ahb;
> +       struct phy      *phy;
>  };
>
>  static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
> @@ -72,7 +75,7 @@ static struct sdhci_pltfm_data sdhci_arasan_pdata = {
>  /**
>   * sdhci_arasan_suspend - Suspend method for the driver
>   * @dev:       Address of the device structure
> - * Returns 0 on success and error value on error
> + * Return: 0 on success and error value on error
>   *
>   * Put the device in a low power state.
>   */
> @@ -88,6 +91,14 @@ static int sdhci_arasan_suspend(struct device *dev)
>         if (ret)
>                 return ret;
>
> +       if (!IS_ERR(sdhci_arasan->phy)) {
> +               ret = phy_power_off(sdhci_arasan->phy);
> +               if (ret) {
> +                       dev_err(dev, "Cannot suspend phy.\n");
> +                       return ret;
> +               }
> +       }
> +
>         clk_disable(pltfm_host->clk);
>         clk_disable(sdhci_arasan->clk_ahb);
>
> @@ -97,7 +108,7 @@ static int sdhci_arasan_suspend(struct device *dev)
>  /**
>   * sdhci_arasan_resume - Resume method for the driver
>   * @dev:       Address of the device structure
> - * Returns 0 on success and error value on error
> + * Return: 0 on success and error value on error
>   *
>   * Resume operation after suspend
>   */
> @@ -118,11 +129,24 @@ static int sdhci_arasan_resume(struct device *dev)
>         ret = clk_enable(pltfm_host->clk);
>         if (ret) {
>                 dev_err(dev, "Cannot enable SD clock.\n");
> -               clk_disable(sdhci_arasan->clk_ahb);
> -               return ret;
> +               goto err_clk_en;
> +       }
> +
> +       if (!IS_ERR(sdhci_arasan->phy)) {
> +               ret = phy_power_on(sdhci_arasan->phy);
> +               if (ret) {
> +                       dev_err(dev, "Cannot resume phy.\n");
> +                       goto err_phy_power;
> +               }
>         }
>
>         return sdhci_resume_host(host);
> +
> +err_phy_power:
> +       clk_disable(pltfm_host->clk);
> +err_clk_en:
> +       clk_disable(sdhci_arasan->clk_ahb);
> +       return ret;
>  }
>  #endif /* ! CONFIG_PM_SLEEP */
>
> @@ -188,6 +212,31 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
>                 goto clk_disable_all;
>         }
>
> +       sdhci_arasan->phy = ERR_PTR(-ENODEV);
> +       if (of_device_is_compatible(pdev->dev.of_node,
> +                                   "arasan,sdhci-5.1")) {
> +               sdhci_arasan->phy = devm_phy_get(&pdev->dev,
> +                                                "phy_arasan");
> +               if (IS_ERR(sdhci_arasan->phy)) {
> +                       ret = PTR_ERR(sdhci_arasan->phy);
> +                       dev_err(&pdev->dev, "No phy for arasan,sdhci-5.1.\n");
> +                       goto clk_disable_all;
> +               }
> +
> +               ret = phy_init(sdhci_arasan->phy);
> +               if (ret < 0) {
> +                       dev_err(&pdev->dev, "phy_init err.\n");
> +                       goto clk_disable_all;
> +               }
> +
> +               ret = phy_power_on(sdhci_arasan->phy);
> +               if (ret < 0) {
> +                       dev_err(&pdev->dev, "phy_power_on err.\n");
> +                       phy_exit(sdhci_arasan->phy);

Remove phy_exit() here, as it's taken care of from the below goto.

> +                       goto err_phy_power;
> +               }
> +       }
> +
>         ret = sdhci_add_host(host);
>         if (ret)
>                 goto err_pltfm_free;
> @@ -196,6 +245,9 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
>
>  err_pltfm_free:
>         sdhci_pltfm_free(pdev);

There is a missing call to phy_power_off() in some error cases.

> +err_phy_power:
> +       if (!IS_ERR(sdhci_arasan->phy))
> +               phy_exit(sdhci_arasan->phy);
>  clk_disable_all:
>         clk_disable_unprepare(clk_xin);
>  clk_dis_ahb:
> @@ -210,6 +262,9 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
>         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
>         struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
>
> +       if (!IS_ERR(sdhci_arasan->phy))

phy_power_off() is needed here as well.

> +               phy_exit(sdhci_arasan->phy);
> +
>         clk_disable_unprepare(sdhci_arasan->clk_ahb);
>
>         return sdhci_pltfm_unregister(pdev);
> --

Kind regards
Uffe
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/