[PATCH 1/2] watchdog: add wdt suspend/resume support
Guenter Roeck
linux at roeck-us.net
Tue Jul 21 20:45:17 PDT 2015
On 07/21/2015 08:26 PM, Eddie Huang wrote:
> From: Greta Zhang <greta.zhang at mediatek.com>
>
> add wdt driver suspend/resume support
>
> Signed-off-by: Greta Zhang <greta.zhang at mediatek.com>
> Signed-off-by: Roger Lu <roger.lu at mediatek.com>
> Signed-off-by: Eddie Huang <eddie.huang at mediatek.com>
> ---
> drivers/watchdog/mtk_wdt.c | 38 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 38 insertions(+)
>
> diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c
> index 938b987..5ef3910 100644
> --- a/drivers/watchdog/mtk_wdt.c
> +++ b/drivers/watchdog/mtk_wdt.c
> @@ -65,6 +65,7 @@ struct mtk_wdt_dev {
> struct watchdog_device wdt_dev;
> void __iomem *wdt_base;
> struct notifier_block restart_handler;
> + bool started;
Any reason why you can not use watchdog_active() ?
> };
>
> static int mtk_reset_handler(struct notifier_block *this, unsigned long mode,
> @@ -125,6 +126,8 @@ static int mtk_wdt_stop(struct watchdog_device *wdt_dev)
> reg &= ~WDT_MODE_EN;
> iowrite32(reg, wdt_base + WDT_MODE);
>
> + mtk_wdt->started = false;
> +
> return 0;
> }
>
> @@ -135,6 +138,8 @@ static int mtk_wdt_start(struct watchdog_device *wdt_dev)
> void __iomem *wdt_base = mtk_wdt->wdt_base;
> int ret;
>
> + mtk_wdt->started = true;
> +
> ret = mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
> if (ret < 0)
> return ret;
> @@ -174,6 +179,8 @@ static int mtk_wdt_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, mtk_wdt);
>
> + mtk_wdt->started = false;
> +
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> mtk_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
> if (IS_ERR(mtk_wdt->wdt_base))
> @@ -221,6 +228,35 @@ static int mtk_wdt_remove(struct platform_device *pdev)
> return 0;
> }
>
> +#ifdef CONFIG_PM
> +static int mtk_wdt_suspend(struct platform_device *pdev, pm_message_t state)
> +{
> + struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev);
> +
> + if (mtk_wdt->started) {
> + mtk_wdt_stop(&mtk_wdt->wdt_dev);
> + mtk_wdt->started = true;
?????
> + }
> +
> + return 0;
> +}
> +
> +static int mtk_wdt_resume(struct platform_device *pdev)
> +{
> + struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev);
> +
> + if (mtk_wdt->started) {
> + mtk_wdt_start(&mtk_wdt->wdt_dev);
> + mtk_wdt_ping(&mtk_wdt->wdt_dev);
> + }
> +
> + return 0;
> +}
> +#else
> +#define mtk_wdt_suspend NULL
> +#define mtk_wdt_resume NULL
> +#endif
> +
> static const struct of_device_id mtk_wdt_dt_ids[] = {
> { .compatible = "mediatek,mt6589-wdt" },
> { /* sentinel */ }
> @@ -230,6 +266,8 @@ MODULE_DEVICE_TABLE(of, mtk_wdt_dt_ids);
> static struct platform_driver mtk_wdt_driver = {
> .probe = mtk_wdt_probe,
> .remove = mtk_wdt_remove,
> + .suspend = mtk_wdt_suspend,
> + .resume = mtk_wdt_resume,
> .driver = {
> .name = DRV_NAME,
> .of_match_table = mtk_wdt_dt_ids,
Typically drivers would use struct dev_pm_ops and
.pm = &mtk_wdt_pm_ops,
Any reason for not using the same mechanism ?
Thanks,
Guenter
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