Re: [PATCH v2 2/2] ata: ahci_platform: runtime resume the devicebefore use

From: Bartlomiej Zolnierkiewicz
Date: Thu Oct 17 2013 - 10:15:30 EST



Hi,

On Wednesday, October 16, 2013 02:42:53 PM Roger Quadros wrote:
> On OMAP platforms the device needs to be runtime resumed before
> it can be accessed. The OMAP HWMOD framework takes care of
> enabling the module and its resources based on the
> device's runtime PM state.
>
> In this patch we runtime resume during .probe() and runtime suspend
> during .remove() (i.e. ahci_host_stop()).
>
> We also update the runtime PM state during .resume().
>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> Signed-off-by: Balaji T K <balajitk@xxxxxx>
> ---
> drivers/ata/ahci_platform.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
> index 5a0f1418..0da3b95 100644
> --- a/drivers/ata/ahci_platform.c
> +++ b/drivers/ata/ahci_platform.c
> @@ -23,6 +23,7 @@
> #include <linux/platform_device.h>
> #include <linux/libata.h>
> #include <linux/ahci_platform.h>
> +#include <linux/pm_runtime.h>
> #include "ahci.h"
>
> static void ahci_host_stop(struct ata_host *host);
> @@ -141,6 +142,9 @@ static int ahci_probe(struct platform_device *pdev)
> }
> }
>
> + pm_runtime_enable(dev);
> + pm_runtime_get_sync(dev);
> +
> hpriv->phy = devm_phy_get(dev, "sata-phy");
> if (IS_ERR(hpriv->phy)) {
> dev_dbg(dev, "can't get sata-phy\n");
> @@ -268,6 +272,9 @@ static void ahci_host_stop(struct ata_host *host)
> clk_disable_unprepare(hpriv->clk);
> clk_put(hpriv->clk);
> }
> +
> + pm_runtime_put_sync(dev);
> + pm_runtime_disable(dev);

It would be better to add proper .remove callback (i.e. named
ahci_remove_one) and put this code there so it matches .probe
callback.

> }
>
> #ifdef CONFIG_PM_SLEEP
> @@ -339,6 +346,11 @@ static int ahci_resume(struct device *dev)
>
> ata_host_resume(host);
>
> + /* We resumed so update PM runtime state */
> + pm_runtime_disable(dev);
> + pm_runtime_set_active(dev);
> + pm_runtime_enable(dev);
> +
> return 0;
>
> disable_unprepare_clk:

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

--
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/