The TMIO MMC controller cannot be powered off to save power, when no
card is plugged in, because then it will not be able to detect a new
card-insertion event. On some implementations, however, it is
possible to switch to using another source to detect card insertion.
This patch adds support for such implementations.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@xxxxxx>
---
drivers/mmc/host/tmio_mmc.h | 3 ++
drivers/mmc/host/tmio_mmc_pio.c | 64 +++++++++++++++++++++++++++++++++++----
include/linux/mfd/tmio.h | 17 ++++++++++
3 files changed, 78 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
index c6bf726..8260bc2 100644
--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -131,4 +131,7 @@ int tmio_mmc_host_resume(struct device *dev);
#define tmio_mmc_host_resume NULL
#endif
+int tmio_mmc_host_runtime_suspend(struct device *dev);
+int tmio_mmc_host_runtime_resume(struct device *dev);
+
#endif
diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index af5d4f6..ad6347b 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -746,6 +746,7 @@ fail:
static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct tmio_mmc_host *host = mmc_priv(mmc);
+ struct tmio_mmc_data *pdata = host->pdata;
unsigned long flags;
spin_lock_irqsave(&host->lock, flags);
@@ -775,13 +776,24 @@ static void tmio_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
/* Power sequence - OFF -> UP -> ON */
if (ios->power_mode == MMC_POWER_UP) {
+ if ((pdata->flags & TMIO_MMC_HAS_COLD_CD) && !pdata->power) {
+ pm_runtime_get_sync(&host->pdev->dev);
+ pdata->power = true;
+ }
/* power up SD bus */
if (host->set_pwr)
host->set_pwr(host->pdev, 1);
} else if (ios->power_mode == MMC_POWER_OFF || !ios->clock) {
/* power down SD bus */
- if (ios->power_mode == MMC_POWER_OFF && host->set_pwr)
- host->set_pwr(host->pdev, 0);
+ if (ios->power_mode == MMC_POWER_OFF) {
+ if (host->set_pwr)
+ host->set_pwr(host->pdev, 0);
+ if ((pdata->flags & TMIO_MMC_HAS_COLD_CD) &&
+ pdata->power) {
+ pdata->power = false;
+ pm_runtime_put(&host->pdev->dev);
+ }
+ }
tmio_mmc_clk_stop(host);
} else {
/* start bus clock */
@@ -853,6 +865,7 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
if (!mmc)
return -ENOMEM;
+ pdata->dev = &pdev->dev;
_host = mmc_priv(mmc);
_host->pdata = pdata;
_host->mmc = mmc;
@@ -886,6 +899,7 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
else
mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+ pdata->power = false;
pm_runtime_enable(&pdev->dev);
ret = pm_runtime_resume(&pdev->dev);
if (ret < 0)
@@ -907,7 +921,8 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host,
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);
+ if (!(pdata->flags & TMIO_MMC_HAS_COLD_CD))
+ pm_runtime_get_noresume(&pdev->dev);
mmc_add_host(mmc);
@@ -937,15 +952,25 @@ void tmio_mmc_host_remove(struct tmio_mmc_host *host)
{
struct platform_device *pdev = host->pdev;
+ /*
+ * We don't have to manipulate pdata->power here: if there is a card in
+ * the slot, the runtime PM is active and our .runtime_resume() will not
+ * be run. If there is no card in the slot and the platform can suspend
+ * the controller, the runtime PM is suspended and pdata->power == false,
+ * so, our .runtime_resume() will not try to detect a card in the slot.
+ */
+ if (host->pdata->flags & TMIO_MMC_HAS_COLD_CD)
+ pm_runtime_get_sync(&pdev->dev);
+
mmc_remove_host(host->mmc);
cancel_delayed_work_sync(&host->delayed_reset_work);
tmio_mmc_release_dma(host);
- iounmap(host->ctl);
- mmc_free_host(host->mmc);
- /* Compensate for pm_runtime_get_sync() in probe() above */
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
+
+ iounmap(host->ctl);
+ mmc_free_host(host->mmc);
}
EXPORT_SYMBOL(tmio_mmc_host_remove);
@@ -970,6 +995,9 @@ int tmio_mmc_host_resume(struct device *dev)
struct mmc_host *mmc = dev_get_drvdata(dev);
struct tmio_mmc_host *host = mmc_priv(mmc);
+ /* The MMC core will perform the complete set up */
+ host->pdata->power = false;
+
if (!host->pm_error)
pm_runtime_get_sync(dev);
@@ -982,4 +1010,28 @@ EXPORT_SYMBOL(tmio_mmc_host_resume);
#endif /* CONFIG_PM */
+int tmio_mmc_host_runtime_suspend(struct device *dev)
+{
+ return 0;
+}
+EXPORT_SYMBOL(tmio_mmc_host_runtime_suspend);
+
+int tmio_mmc_host_runtime_resume(struct device *dev)
+{
+ struct mmc_host *mmc = dev_get_drvdata(dev);
+ struct tmio_mmc_host *host = mmc_priv(mmc);
+ struct tmio_mmc_data *pdata = host->pdata;
+
+ tmio_mmc_reset(host);
+
+ if (pdata->power) {
+ /* Only entered after a card-insert interrupt */
+ tmio_mmc_set_ios(mmc, &mmc->ios);
+ mmc_detect_change(mmc, msecs_to_jiffies(100));
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(tmio_mmc_host_runtime_resume);
+
MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 8e70310..5a90266 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -4,6 +4,7 @@
#include <linux/fb.h>
#include <linux/io.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#define tmio_ioread8(addr) readb(addr)
#define tmio_ioread16(addr) readw(addr)
@@ -61,6 +62,12 @@
* Some controllers can support SDIO IRQ signalling.
*/
#define TMIO_MMC_SDIO_IRQ (1 << 2)
+/*
+ * Some platforms can detect card insertion events with controller powered
+ * down, in which case they have to call tmio_mmc_cd_wakeup() to power up the
+ * controller and report the event to the driver.
+ */
+#define TMIO_MMC_HAS_COLD_CD (1 << 3)
int tmio_core_mmc_enable(void __iomem *cnf, int shift, unsigned long base);
int tmio_core_mmc_resume(void __iomem *cnf, int shift, unsigned long base);
@@ -82,11 +89,21 @@ struct tmio_mmc_data {
unsigned long flags;
u32 ocr_mask; /* available voltages */
struct tmio_mmc_dma *dma;
+ struct device *dev;
+ bool power;
void (*set_pwr)(struct platform_device *host, int state);
void (*set_clk_div)(struct platform_device *host, int state);
int (*get_cd)(struct platform_device *host);
};
+static inline void tmio_mmc_cd_wakeup(struct tmio_mmc_data *pdata)
+{
+ if (pdata && !pdata->power) {
+ pdata->power = true;
+ pm_runtime_get(pdata->dev);
+ }
+}
+
/*
* data for the NAND controller
*/
--
1.7.2.5
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