diff mbox series

[V5,5/9] mmc: bcm2835: add suspend/resume pm support

Message ID 20241025103621.4780-6-wahrenst@gmx.net
State New
Headers show
Series ARM: bcm2835: Implement initial S2Idle for Raspberry Pi | expand

Commit Message

Stefan Wahren Oct. 25, 2024, 10:36 a.m. UTC 
Add a minimalistic suspend/resume PM support.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
---
 drivers/mmc/host/bcm2835.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

--
2.34.1

Comments

Ulf Hansson Oct. 28, 2024, 10:56 a.m. UTC | #1 
On Fri, 25 Oct 2024 at 12:36, Stefan Wahren <wahrenst@gmx.net> wrote:
>
> Add a minimalistic suspend/resume PM support.
>
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> ---
>  drivers/mmc/host/bcm2835.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>
> diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
> index 107666b7c1c8..17c327b7b5cc 100644
> --- a/drivers/mmc/host/bcm2835.c
> +++ b/drivers/mmc/host/bcm2835.c
> @@ -1343,6 +1343,30 @@ static int bcm2835_add_host(struct bcm2835_host *host)
>         return 0;
>  }
>
> +static int bcm2835_suspend(struct device *dev)
> +{
> +       struct bcm2835_host *host = dev_get_drvdata(dev);
> +
> +       if (!host->data_complete) {
> +               dev_warn(dev, "Suspend is prevented\n");
> +               return -EBUSY;
> +       }

This should not be needed.

The mmc core makes sure all outstanding requests have been flushed,
before the host controller becomes suspended.

> +
> +       clk_disable_unprepare(host->clk);
> +
> +       return 0;
> +}
> +
> +static int bcm2835_resume(struct device *dev)
> +{
> +       struct bcm2835_host *host = dev_get_drvdata(dev);
> +
> +       return clk_prepare_enable(host->clk);
> +}
> +
> +static DEFINE_SIMPLE_DEV_PM_OPS(bcm2835_pm_ops, bcm2835_suspend,
> +                               bcm2835_resume);
> +
>  static int bcm2835_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
> @@ -1471,6 +1495,7 @@ static struct platform_driver bcm2835_driver = {
>                 .name           = "sdhost-bcm2835",
>                 .probe_type     = PROBE_PREFER_ASYNCHRONOUS,
>                 .of_match_table = bcm2835_match,
> +               .pm = pm_ptr(&bcm2835_pm_ops),
>         },
>  };
>  module_platform_driver(bcm2835_driver);

Kind regards
Uffe
diff mbox series

Patch

diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index 107666b7c1c8..17c327b7b5cc 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c
@@ -1343,6 +1343,30 @@  static int bcm2835_add_host(struct bcm2835_host *host)
 	return 0;
 }

+static int bcm2835_suspend(struct device *dev)
+{
+	struct bcm2835_host *host = dev_get_drvdata(dev);
+
+	if (!host->data_complete) {
+		dev_warn(dev, "Suspend is prevented\n");
+		return -EBUSY;
+	}
+
+	clk_disable_unprepare(host->clk);
+
+	return 0;
+}
+
+static int bcm2835_resume(struct device *dev)
+{
+	struct bcm2835_host *host = dev_get_drvdata(dev);
+
+	return clk_prepare_enable(host->clk);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(bcm2835_pm_ops, bcm2835_suspend,
+				bcm2835_resume);
+
 static int bcm2835_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -1471,6 +1495,7 @@  static struct platform_driver bcm2835_driver = {
 		.name		= "sdhost-bcm2835",
 		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
 		.of_match_table	= bcm2835_match,
+		.pm = pm_ptr(&bcm2835_pm_ops),
 	},
 };
 module_platform_driver(bcm2835_driver);