aboutsummaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorOhad Ben-Cohen <ohad@wizery.com>2010-11-19 09:29:09 +0200
committerChris Ball <cjb@laptop.org>2010-11-19 17:07:01 -0500
commited919b0125b26dcc052e44836f66e7e1f5c49c7e (patch)
tree10abd2b197488ee2c75e693e9422668481e5e4ce /drivers
parent4d0812c37f2f6cf6fc7ca086b5a5e572cbbe7f6d (diff)
downloadmrst-s0i3-test-ed919b0125b26dcc052e44836f66e7e1f5c49c7e.tar.gz
mrst-s0i3-test-ed919b0125b26dcc052e44836f66e7e1f5c49c7e.tar.xz
mrst-s0i3-test-ed919b0125b26dcc052e44836f66e7e1f5c49c7e.zip
mmc: sdio: fix runtime PM anomalies by introducing MMC_CAP_POWER_OFF_CARD
Some board/card/host configurations are not capable of powering off the card after boot. To support such configurations, and to allow smoother transition to runtime PM behavior, MMC_CAP_POWER_OFF_CARD is added, so hosts need to explicitly indicate whether it's OK to power off their cards after boot. SDIO core will enable runtime PM for a card only if that cap is set. As a result, the card will be powered down after boot, and will only be powered up again when a driver is loaded (and then it's up to the driver to decide whether power will be kept or not). This will prevent sdio_bus_probe() failures with setups that do not support powering off the card. Reported-and-tested-by: Daniel Drake <dsd@laptop.org> Reported-and-tested-by: Arnd Hannemann <arnd@arndnet.de> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com> Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/mmc/core/sdio.c37
-rw-r--r--drivers/mmc/core/sdio_bus.c33
2 files changed, 45 insertions, 25 deletions
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 42a949b723b..efef5f94ac4 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -547,9 +547,11 @@ static void mmc_sdio_detect(struct mmc_host *host)
BUG_ON(!host->card);
/* Make sure card is powered before detecting it */
- err = pm_runtime_get_sync(&host->card->dev);
- if (err < 0)
- goto out;
+ if (host->caps & MMC_CAP_POWER_OFF_CARD) {
+ err = pm_runtime_get_sync(&host->card->dev);
+ if (err < 0)
+ goto out;
+ }
mmc_claim_host(host);
@@ -571,7 +573,8 @@ static void mmc_sdio_detect(struct mmc_host *host)
* is about to show up at this point, the _sync variant is
* desirable anyway.
*/
- pm_runtime_put_sync(&host->card->dev);
+ if (host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_put_sync(&host->card->dev);
out:
if (err) {
@@ -728,16 +731,21 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
card = host->card;
/*
- * Let runtime PM core know our card is active
+ * Enable runtime PM only if supported by host+card+board
*/
- err = pm_runtime_set_active(&card->dev);
- if (err)
- goto remove;
+ if (host->caps & MMC_CAP_POWER_OFF_CARD) {
+ /*
+ * Let runtime PM core know our card is active
+ */
+ err = pm_runtime_set_active(&card->dev);
+ if (err)
+ goto remove;
- /*
- * Enable runtime PM for this card
- */
- pm_runtime_enable(&card->dev);
+ /*
+ * Enable runtime PM for this card
+ */
+ pm_runtime_enable(&card->dev);
+ }
/*
* The number of functions on the card is encoded inside
@@ -755,9 +763,10 @@ int mmc_attach_sdio(struct mmc_host *host, u32 ocr)
goto remove;
/*
- * Enable Runtime PM for this func
+ * Enable Runtime PM for this func (if supported)
*/
- pm_runtime_enable(&card->sdio_func[i]->dev);
+ if (host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_enable(&card->sdio_func[i]->dev);
}
mmc_release_host(host);
diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
index 2716c7ab6bb..203da443e33 100644
--- a/drivers/mmc/core/sdio_bus.c
+++ b/drivers/mmc/core/sdio_bus.c
@@ -17,6 +17,7 @@
#include <linux/pm_runtime.h>
#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
#include <linux/mmc/sdio_func.h>
#include "sdio_cis.h"
@@ -132,9 +133,11 @@ static int sdio_bus_probe(struct device *dev)
* it should call pm_runtime_put_noidle() in its probe routine and
* pm_runtime_get_noresume() in its remove routine.
*/
- ret = pm_runtime_get_sync(dev);
- if (ret < 0)
- goto out;
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD) {
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ goto out;
+ }
/* Set the default block size so the driver is sure it's something
* sensible. */
@@ -151,7 +154,8 @@ static int sdio_bus_probe(struct device *dev)
return 0;
disable_runtimepm:
- pm_runtime_put_noidle(dev);
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_put_noidle(dev);
out:
return ret;
}
@@ -160,12 +164,14 @@ static int sdio_bus_remove(struct device *dev)
{
struct sdio_driver *drv = to_sdio_driver(dev->driver);
struct sdio_func *func = dev_to_sdio_func(dev);
- int ret;
+ int ret = 0;
/* Make sure card is powered before invoking ->remove() */
- ret = pm_runtime_get_sync(dev);
- if (ret < 0)
- goto out;
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD) {
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0)
+ goto out;
+ }
drv->remove(func);
@@ -178,10 +184,12 @@ static int sdio_bus_remove(struct device *dev)
}
/* First, undo the increment made directly above */
- pm_runtime_put_noidle(dev);
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_put_noidle(dev);
/* Then undo the runtime PM settings in sdio_bus_probe() */
- pm_runtime_put_noidle(dev);
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_put_noidle(dev);
out:
return ret;
@@ -191,6 +199,8 @@ out:
static int sdio_bus_pm_prepare(struct device *dev)
{
+ struct sdio_func *func = dev_to_sdio_func(dev);
+
/*
* Resume an SDIO device which was suspended at run time at this
* point, in order to allow standard SDIO suspend/resume paths
@@ -212,7 +222,8 @@ static int sdio_bus_pm_prepare(struct device *dev)
* since there is little point in failing system suspend if a
* device can't be resumed.
*/
- pm_runtime_resume(dev);
+ if (func->card->host->caps & MMC_CAP_POWER_OFF_CARD)
+ pm_runtime_resume(dev);
return 0;
}