mmc: add runtime and system power-management support to the MMCIF driver
Adding support for runtime power-management to the MMCIF driver allows
it to save power as long as no card is present. To also allow to turn
off the power domain at that time, we release DMA channels during that
time, since on some sh-mobile systems the DMA controller(s) and the
MMCIF block belong to the same power domain. System-wide power
management has been tested with experimental PM patches on AP4-based
systems.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index d3871b6..14f8edb 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 completion intr_wait;
enum mmcif_state state;
spinlock_t lock;
+ bool power;
/* DMA support */
struct dma_chan *chan_rx;
@@ -877,11 +879,24 @@
if (ios->power_mode == MMC_POWER_UP) {
if (p->set_pwr)
p->set_pwr(host->pd, ios->power_mode);
+ if (!host->power) {
+ /* See if we also get DMA */
+ sh_mmcif_request_dma(host, host->pd->dev.platform_data);
+ 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);
+ sh_mmcif_release_dma(host);
+ host->power = false;
+ }
+ if (p->down_pwr)
+ p->down_pwr(host->pd);
+ }
host->state = STATE_IDLE;
return;
}
@@ -957,7 +972,7 @@
sh_mmcif_bitclr(host, MMCIF_CE_INT_MASK, state);
err = 1;
} else {
- dev_dbg(&host->pd->dev, "Not support int\n");
+ dev_dbg(&host->pd->dev, "Unsupported interrupt: 0x%x\n", state);
sh_mmcif_writel(host->addr, MMCIF_CE_INT, ~state);
sh_mmcif_bitclr(host, MMCIF_CE_INT_MASK, state);
err = 1;
@@ -1053,8 +1068,12 @@
sh_mmcif_sync_reset(host);
platform_set_drvdata(pdev, host);
- /* See if we also get DMA */
- sh_mmcif_request_dma(host, pd);
+ pm_runtime_enable(&pdev->dev);
+ host->power = false;
+
+ ret = pm_runtime_resume(&pdev->dev);
+ if (ret < 0)
+ goto clean_up2;
mmc_add_host(mmc);
@@ -1063,13 +1082,13 @@
ret = request_irq(irq[0], sh_mmcif_intr, 0, "sh_mmc:error", host);
if (ret) {
dev_err(&pdev->dev, "request_irq error (sh_mmc:error)\n");
- goto clean_up2;
+ goto clean_up3;
}
ret = request_irq(irq[1], sh_mmcif_intr, 0, "sh_mmc:int", host);
if (ret) {
free_irq(irq[0], host);
dev_err(&pdev->dev, "request_irq error (sh_mmc:int)\n");
- goto clean_up2;
+ goto clean_up3;
}
sh_mmcif_detect(host->mmc);
@@ -1079,7 +1098,11 @@
sh_mmcif_readl(host->addr, MMCIF_CE_VERSION) & 0x0000ffff);
return ret;
+clean_up3:
+ mmc_remove_host(mmc);
+ pm_runtime_suspend(&pdev->dev);
clean_up2:
+ pm_runtime_disable(&pdev->dev);
clk_disable(host->hclk);
clean_up1:
mmc_free_host(mmc);
@@ -1094,9 +1117,9 @@
struct sh_mmcif_host *host = platform_get_drvdata(pdev);
int irq[2];
- mmc_remove_host(host->mmc);
- sh_mmcif_release_dma(host);
+ pm_runtime_get_sync(&pdev->dev);
+ mmc_remove_host(host->mmc);
sh_mmcif_writel(host->addr, MMCIF_CE_INT_MASK, MASK_ALL);
if (host->addr)
@@ -1112,15 +1135,52 @@
clk_disable(host->hclk);
mmc_free_host(host->mmc);
+ pm_runtime_put_sync(&pdev->dev);
+ 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,
},
};