This patch adds a very crude runtime power-management to the TMIO MMC
driver. It only takes care to enable the hardware on probe() and keep
it enabled until remove(), at which time it disables it again. A
finer grained runtime PM would require implementing card detection
support on switched off interface.
System-wide power management has been verified with experimental PM
patches on AP4-based systems.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
---
This patch slightly changes driver's PM behaviour also on non-SDHI
systems, namely, it adds a reset call to the resume path. If this is
undesired, it can be easily moved to the SDHI-specific part. On SDHI it
helps to faster recover the controller and avoid failing MMC requests due
to timing out interrupts, and a repeated request retry from the core.
Runtime PM might change, if the core behaviour changes on driver unbind.
drivers/mmc/host/sh_mobile_sdhi.c | 6 ++++
drivers/mmc/host/tmio_mmc.c | 11 ++----
drivers/mmc/host/tmio_mmc.h | 8 +++++
drivers/mmc/host/tmio_mmc_pio.c | 58 +++++++++++++++++++++++++++++++++++--
4 files changed, 73 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
index cc70123..f60e954 100644
--- a/drivers/mmc/host/sh_mobile_sdhi.c
+++ b/drivers/mmc/host/sh_mobile_sdhi.c
@@ -143,10 +143,16 @@ static int sh_mobile_sdhi_remove(struct platform_device *pdev)
return 0;
}
+static const struct dev_pm_ops tmio_mmc_dev_pm_ops = {
+ .suspend = tmio_mmc_host_suspend,
+ .resume = tmio_mmc_host_resume,
+};
+
static struct platform_driver sh_mobile_sdhi_driver = {
.driver = {
.name = "sh_mobile_sdhi",
.owner = THIS_MODULE,
+ .pm = &tmio_mmc_dev_pm_ops,
},
.probe = sh_mobile_sdhi_probe,
.remove = __devexit_p(sh_mobile_sdhi_remove),
diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 79c5684..be739f7 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -30,7 +30,7 @@ static int tmio_mmc_suspend(struct platform_device *dev, pm_message_t state)
struct mmc_host *mmc = platform_get_drvdata(dev);
int ret;
- ret = mmc_suspend_host(mmc);
+ ret = tmio_mmc_host_suspend(&dev->dev);
/* Tell MFD core it can disable us now.*/
if (!ret && cell->disable)
@@ -46,15 +46,12 @@ static int tmio_mmc_resume(struct platform_device *dev)
int ret = 0;
/* Tell the MFD core we are ready to be enabled */
- if (cell->resume) {
+ if (cell->resume)
ret = cell->resume(dev);
- if (ret)
- goto out;
- }
- mmc_resume_host(mmc);
+ if (!ret)
+ ret = tmio_mmc_host_resume(&dev->dev);
-out:
return ret;
}
#else
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
index f353624..249c724 100644
--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -121,4 +121,12 @@ static inline void tmio_mmc_release_dma(struct tmio_mmc_host *host)
}
#endif
+#ifdef CONFIG_PM
+int tmio_mmc_host_suspend(struct device *dev);
+int tmio_mmc_host_resume(struct device *dev);
+#else
+#define tmio_mmc_host_suspend NULL
+#define tmio_mmc_host_resume NULL
+#endif
+
#endif
diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index f4fac9f..d1791ba 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -39,6 +39,7 @@
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/scatterlist.h>
#include <linux/workqueue.h>
#include <linux/spinlock.h>
@@ -884,12 +885,17 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
else
mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+ pm_runtime_enable(&pdev->dev);
+ ret = pm_runtime_resume(&pdev->dev);
+ if (ret < 0)
+ goto pm_disable;
+
tmio_mmc_clk_stop(_host);
tmio_mmc_reset(_host);
ret = platform_get_irq(pdev, 0);
if (ret < 0)
- goto unmap_ctl;
+ goto pm_suspend;
_host->irq = ret;
@@ -900,7 +906,7 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
ret = request_irq(_host->irq, tmio_mmc_irq, IRQF_DISABLED |
IRQF_TRIGGER_FALLING, dev_name(&pdev->dev), _host);
if (ret)
- goto unmap_ctl;
+ goto pm_suspend;
spin_lock_init(&_host->lock);
@@ -910,6 +916,9 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
/* See if we also get DMA */
tmio_mmc_request_dma(_host, pdata);
+ /* We have to keep the device powered for its card detection to work */
+ pm_runtime_get_noresume(&pdev->dev);
+
mmc_add_host(mmc);
/* Unmask the IRQs we want to know about */
@@ -924,7 +933,10 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
return 0;
-unmap_ctl:
+pm_suspend:
+ pm_runtime_suspend(&pdev->dev);
+pm_disable:
+ pm_runtime_disable(&pdev->dev);
iounmap(_host->ctl);
host_free:
mmc_free_host(mmc);
@@ -935,13 +947,53 @@ EXPORT_SYMBOL(tmio_mmc_host_probe);
void tmio_mmc_host_remove(struct tmio_mmc_host *host)
{
+ struct platform_device *pdev = host->pdev;
+
mmc_remove_host(host->mmc);
cancel_delayed_work_sync(&host->delayed_reset_work);
tmio_mmc_release_dma(host);
free_irq(host->irq, host);
iounmap(host->ctl);
mmc_free_host(host->mmc);
+
+ /*
+ * Now rtpm usage_count = 2, because we incremented it once in probe()
+ * above, and dd.c incremented it again, before calling .release(). So.
+ * to power the device down we have to decrement the counter to 0 and
+ * suspend it, because after our disable() suspending from dd.c will
+ * only decrement the counter, but not call any callbacks
+ */
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_get_noresume(&pdev->dev);
}
EXPORT_SYMBOL(tmio_mmc_host_remove);
+#ifdef CONFIG_PM
+int tmio_mmc_host_suspend(struct device *dev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(dev);
+ struct tmio_mmc_host *host = mmc_priv(mmc);
+ int ret = mmc_suspend_host(mmc);
+
+ if (!ret)
+ tmio_mmc_disable_mmc_irqs(host, TMIO_MASK_ALL);
+
+ return ret;
+}
+EXPORT_SYMBOL(tmio_mmc_host_suspend);
+
+int tmio_mmc_host_resume(struct device *dev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(dev);
+
+ tmio_mmc_reset(mmc_priv(mmc));
+
+ return mmc_resume_host(mmc);
+}
+EXPORT_SYMBOL(tmio_mmc_host_resume);
+
+#endif /* CONFIG_PM */
+
MODULE_LICENSE("GPL v2");
--
1.7.2.5
--
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