[PATCH v2] mmc: sdhci at91: add PM support

From: Ludovic Desroches
Date: Tue Nov 10 2015 - 05:36:42 EST


Add runtime PM support and use runtime_force_suspend|resume() for system
PM.

Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
---

Changes:
- from v1: take a runtime PM centric approach

drivers/mmc/host/sdhci-of-at91.c | 66 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 65 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 06d0b50..5dbe0ce 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -21,6 +21,8 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>

#include "sdhci-pltfm.h"

@@ -51,6 +53,62 @@ static const struct of_device_id sdhci_at91_dt_match[] = {
{}
};

+#ifdef CONFIG_PM
+static int sdhci_at91_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_at91_priv *priv = pltfm_host->priv;
+ int ret;
+
+ ret = sdhci_runtime_suspend_host(host);
+
+ clk_disable_unprepare(priv->gck);
+ clk_disable_unprepare(priv->hclock);
+ clk_disable_unprepare(priv->mainck);
+
+ return ret;
+}
+
+static int sdhci_at91_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_at91_priv *priv = pltfm_host->priv;
+ int ret;
+
+ ret = clk_prepare_enable(priv->mainck);
+ if (ret) {
+ dev_err(dev, "can't enable mainck\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(priv->hclock);
+ if (ret) {
+ dev_err(dev, "can't enable hclock\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(priv->gck);
+ if (ret) {
+ dev_err(dev, "can't enable gck\n");
+ return ret;
+ }
+
+ return sdhci_runtime_resume_host(host);
+}
+#endif /* CONFIG_PM_RUNTIME */
+
+static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,
+ sdhci_at91_runtime_resume,
+ NULL)
+};
+
static int sdhci_at91_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
@@ -148,6 +206,11 @@ static int sdhci_at91_probe(struct platform_device *pdev)
if (ret)
goto clocks_disable_unprepare;

+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
+ pm_runtime_use_autosuspend(&pdev->dev);
+
return 0;

clocks_disable_unprepare:
@@ -165,6 +228,7 @@ static int sdhci_at91_remove(struct platform_device *pdev)
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_at91_priv *priv = pltfm_host->priv;

+ pm_runtime_disable(&pdev->dev);
sdhci_pltfm_unregister(pdev);

clk_disable_unprepare(priv->gck);
@@ -178,7 +242,7 @@ static struct platform_driver sdhci_at91_driver = {
.driver = {
.name = "sdhci-at91",
.of_match_table = sdhci_at91_dt_match,
- .pm = SDHCI_PLTFM_PMOPS,
+ .pm = &sdhci_at91_dev_pm_ops,
},
.probe = sdhci_at91_probe,
.remove = sdhci_at91_remove,
--
2.5.0

--
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/