Re: [PATCH v3 3/3] mmc: sdhci-of-arasan: add runtime pm support

From: Shawn Lin
Date: Tue Oct 20 2015 - 04:41:40 EST


On 2015/10/20 16:03, Michal Simek wrote:
Hi,

On 10/20/2015 09:05 AM, Shawn Lin wrote:
This patch add runtime_suspend and runtime_resume for
sdhci-of-arasan. Currently we also suspend phy at
runtime_suspend for power-saving.

Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---

Changes in v2: None

drivers/mmc/host/sdhci-of-arasan.c | 80 ++++++++++++++++++++++++++++++++++++--
1 file changed, 77 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 85bd0f9d..579f7bb 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -30,6 +30,8 @@
#define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT)
#define CLK_CTRL_TIMEOUT_MIN_EXP 13

+#define ARASAN_RPM_DELAY_MS 50
+
/**
* struct sdhci_arasan_data
* @clk_ahb: Pointer to the AHB clock
@@ -183,8 +185,70 @@ static int sdhci_arasan_resume(struct device *dev)
}
#endif /* ! CONFIG_PM_SLEEP */

-static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
- sdhci_arasan_resume);
+
+#ifdef CONFIG_PM
+static int sdhci_arasan_runtime_suspend(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
+ int ret;
+
+ ret = sdhci_runtime_suspend_host(host);
+ if (ret)
+ return ret;
+
+ if (!IS_ERR(sdhci_arasan->phy)) {
+ ret = sdhci_arasan_suspend_phy(sdhci_arasan->phy);
+ if (ret) {
+ dev_err(dev, "Cannot suspend phy at runtime.\n");
+ sdhci_runtime_resume_host(host);
+ return ret;
+ }
+ }
+
+ clk_disable_unprepare(sdhci_arasan->clk_ahb);
+ clk_disable_unprepare(pltfm_host->clk);
+
+ return 0;
+}
+
+static int sdhci_arasan_runtime_resume(struct device *dev)
+{
+ struct sdhci_host *host = dev_get_drvdata(dev);
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = pltfm_host->priv;
+ int ret;
+
+ clk_prepare_enable(pltfm_host->clk);
+ clk_prepare_enable(sdhci_arasan->clk_ahb);
+
+ if (!IS_ERR(sdhci_arasan->phy)) {
+ ret = sdhci_arasan_resume_phy(sdhci_arasan->phy);
+ if (ret) {
+ dev_err(dev, "Cannot resume phy at runtime.\n");
+ clk_disable_unprepare(sdhci_arasan->clk_ahb);
+ clk_disable_unprepare(pltfm_host->clk);
+ return ret;
+ }
+ }
+
+ return sdhci_runtime_resume_host(host);
+}
+#endif
+
+#ifdef CONFIG_PM
+static const struct dev_pm_ops sdhci_arasan_pmops = {
+ SET_SYSTEM_SLEEP_PM_OPS(sdhci_arasan_suspend, sdhci_arasan_resume)
+ SET_RUNTIME_PM_OPS(sdhci_arasan_runtime_suspend,
+ sdhci_arasan_runtime_resume, NULL)
+};
+
+#define SDHCI_ARASAN_PMOPS (&sdhci_arasan_pmops)
+
+#else
+#define SDHCI_ARASAN_PMOPS NULL
+#endif

This is completely wrong. SET_SYSTEM_SLEEP_PM_OPS, SET_RUNTIME_PM_OPS
have both declarations for !PM_SLEEP, !PM cases. It means you can remove
this ifdef mess.

I was doing experiment with your code and you need to add __maybe_unused
for functions which are not used when certain functions are not wired
for !PM, !PM_SLEEP cases.

Something like this should be added to any SDHCI header. (or Using
macros). Definitely this should be tested for all combinations.
#if !defined(CONFIG_PM)
static inline int sdhci_suspend_host(struct sdhci_host *host) { return -1; }
static inline int sdhci_resume_host(struct sdhci_host *host) { return -1; }
static inline int sdhci_runtime_suspend_host(struct sdhci_host *host) {
return -1; }
static inline int sdhci_runtime_resume_host(struct sdhci_host *host) {
return -1; }
#endif


Thanks for pointing out it.

Actually I took a little bit from
sdhci-pxav3.c and sdhci-s3c.c. So I didn't find the mistake.

I now look into the SET_SYSTEM_SLEEP_PM_OPS, SET_RUNTIME_PM_OPS, yes,
it matches the case you mentioned.

Definitely I will fix it. :)

So let me wait for Ulf if he has some comments for this patchset and then re-spin my the next version.



static int sdhci_arasan_probe(struct platform_device *pdev)
{
@@ -272,6 +336,11 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
goto clk_disable_all;
}

+ pm_runtime_set_autosuspend_delay(&pdev->dev, ARASAN_RPM_DELAY_MS);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_suspend_ignore_children(&pdev->dev, 1);
+
ret = sdhci_add_host(host);
if (ret)
goto err_pltfm_free;
@@ -279,6 +348,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
return 0;

err_pltfm_free:
+ pm_runtime_disable(&pdev->dev);
sdhci_pltfm_free(pdev);
clk_disable_all:
clk_disable_unprepare(clk_xin);
@@ -297,6 +367,10 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
if (!IS_ERR(sdhci_arasan->phy))
phy_exit(sdhci_arasan->phy);

+ pm_runtime_get_sync(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
clk_disable_unprepare(sdhci_arasan->clk_ahb);

return sdhci_pltfm_unregister(pdev);
@@ -314,7 +388,7 @@ static struct platform_driver sdhci_arasan_driver = {
.driver = {
.name = "sdhci-arasan",
.of_match_table = sdhci_arasan_of_match,
- .pm = &sdhci_arasan_dev_pm_ops,
+ .pm = SDHCI_ARASAN_PMOPS,

Keep origin name here. No reason for this macro at all.

Got it.


},
.probe = sdhci_arasan_probe,
.remove = sdhci_arasan_remove,


Thanks,
Michal





--
Best Regards
Shawn Lin

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