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| author | Jisheng Zhang <jszhang@marvell.com> | 2015-01-04 23:15:47 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-03-06 14:52:52 -0800 |
| commit | 4d025d8000898c8e14bbf9a793063aadae31045b (patch) | |
| tree | f1ff7d12e5c549b2aeb4b49d5cabdc122a343771 | |
| parent | 122982283616020d723300251644ff98fad834ee (diff) | |
| download | lwn-4d025d8000898c8e14bbf9a793063aadae31045b.tar.gz lwn-4d025d8000898c8e14bbf9a793063aadae31045b.zip | |
mmc: sdhci-pxav3: fix unbalanced clock issues during probe
commit 62cf983ad84275f8580c807e5e596216c46773cf upstream.
Commit 0dcaa2499b7d ("sdhci-pxav3: Fix runtime PM initialization") tries
to fix one hang issue caused by calling sdhci_add_host() on a suspended
device. The fix enables the clock twice, once by clk_prepare_enable() and
another by pm_runtime_get_sync(), meaning that the clock will never be
gated at runtime PM suspend. I observed the power consumption regression on
Marvell BG2Q SoCs.
In fact, the fix is not correct. There still be a very small window
during which a runtime suspend might somehow occur after pm_runtime_enable()
but before pm_runtime_get_sync().
This patch fixes all of the two problems by just incrementing the usage
counter before pm_runtime_enable(). It also adjust the order of disabling
runtime pm and storing the usage count in the error path to handle clock
gating properly.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/mmc/host/sdhci-pxav3.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c index 5036d7d39529..bb50da1cab98 100644 --- a/drivers/mmc/host/sdhci-pxav3.c +++ b/drivers/mmc/host/sdhci-pxav3.c @@ -355,10 +355,11 @@ static int sdhci_pxav3_probe(struct platform_device *pdev) } } - pm_runtime_enable(&pdev->dev); - pm_runtime_get_sync(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_set_active(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, PXAV3_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); @@ -381,8 +382,8 @@ static int sdhci_pxav3_probe(struct platform_device *pdev) return 0; err_add_host: - pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); err_of_parse: err_cd_req: clk_disable_unprepare(clk); |