Adding support for runtime power-management to the MMCIF driver allows
it to save power as long as no card is present. System-wide power
management has been verified with experimental PM patches on AP4-
based systems.
Signed-off-by: Guennadi Liakhovetski <g.liakhovet...@gmx.de>
Cc: Simon Horman <ho...@verge.net.au>
Cc: Magnus Damm <d...@opensource.se>
---
To use this patch experimental PM patches from Magnus are needed, but even
without them this patch can be applied and shouldn't cause any
regressions.
drivers/mmc/host/sh_mmcif.c | 59 +++++++++++++++++++++++++++++++++++++++++-
1 files changed, 57 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index d3871b6..519d827 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -29,6 +29,7 @@
#include <linux/mmc/sh_mmcif.h>
#include <linux/pagemap.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/spinlock.h>
#define DRIVER_NAME "sh_mmcif"
@@ -173,6 +174,7 @@ struct sh_mmcif_host {
struct completion intr_wait;
enum mmcif_state state;
spinlock_t lock;
+ bool power;
/* DMA support */
struct dma_chan *chan_rx;
@@ -877,11 +879,21 @@ static void sh_mmcif_set_ios(struct mmc_host *mmc, struct
mmc_ios *ios)
if (ios->power_mode == MMC_POWER_UP) {
if (p->set_pwr)
p->set_pwr(host->pd, ios->power_mode);
+ if (!host->power) {
+ pm_runtime_get_sync(&host->pd->dev);
+ host->power = true;
+ }
} else if (ios->power_mode == MMC_POWER_OFF || !ios->clock) {
/* clock stop */
sh_mmcif_clock_control(host, 0);
- if (ios->power_mode == MMC_POWER_OFF && p->down_pwr)
- p->down_pwr(host->pd);
+ if (ios->power_mode == MMC_POWER_OFF) {
+ if (host->power) {
+ pm_runtime_put(&host->pd->dev);
+ host->power = false;
+ }
+ if (p->down_pwr)
+ p->down_pwr(host->pd);
+ }
host->state = STATE_IDLE;
return;
}
@@ -1053,6 +1065,12 @@ static int __devinit sh_mmcif_probe(struct
platform_device *pdev)
sh_mmcif_sync_reset(host);
platform_set_drvdata(pdev, host);
+ pm_runtime_enable(&pdev->dev);
+ host->power = false;
+ ret = pm_runtime_resume(&pdev->dev);
+ if (ret < 0)
+ goto clean_up2;
+
/* See if we also get DMA */
sh_mmcif_request_dma(host, pd);
@@ -1080,6 +1098,7 @@ static int __devinit sh_mmcif_probe(struct
platform_device *pdev)
return ret;
clean_up2:
+ pm_runtime_disable(&pdev->dev);
clk_disable(host->hclk);
clean_up1:
mmc_free_host(mmc);
@@ -1112,15 +1131,51 @@ static int __devexit sh_mmcif_remove(struct
platform_device *pdev)
clk_disable(host->hclk);
mmc_free_host(host->mmc);
+ pm_runtime_disable(&pdev->dev);
return 0;
}
+#ifdef CONFIG_PM
+static int sh_mmcif_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sh_mmcif_host *host = platform_get_drvdata(pdev);
+ int ret = mmc_suspend_host(host->mmc);
+
+ if (!ret) {
+ sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);
+ clk_disable(host->hclk);
+ }
+
+ return ret;
+}
+
+static int sh_mmcif_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sh_mmcif_host *host = platform_get_drvdata(pdev);
+
+ clk_enable(host->hclk);
+
+ return mmc_resume_host(host->mmc);
+}
+#else
+#define sh_mmcif_suspend NULL
+#define sh_mmcif_resume NULL
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops sh_mmcif_dev_pm_ops = {
+ .suspend = sh_mmcif_suspend,
+ .resume = sh_mmcif_resume,
+};
+
static struct platform_driver sh_mmcif_driver = {
.probe = sh_mmcif_probe,
.remove = sh_mmcif_remove,
.driver = {
.name = DRIVER_NAME,
+ .pm = &sh_mmcif_dev_pm_ops,
},
};
--
1.7.2.5
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