On Mon, Nov 1, 2010 at 10:05 AM, Arnd Hannemann <arnd@xxxxxxxxxx> wrote:
> No, actually mmc_sdio_init_card() is called _before_ sdio_bus_probe
Yes, it is called once at boot while the card is mmc_rescan()ed.
But that's not interesting, because the card is then powered down, and
will only be powered on again when it is probed with a driver.
> Also mmd_sdio_resume is not called at all.
Sorry, I meant mmc_sdio_restore_host.
You should see something like this:
sdio_bus_probe - >
... (runtime PM function calls) ... ->
mmc_power_restore_host ->
mmc_sdio_power_restore ->
mmc_sdio_init_card -> ...
We have 1 report where the latter mmc_sdio_init_card fails at this
point, and I'm interested to know whether it fails for you, too (and
if yes, where). If it is not even called, I'd appreciate if you can
check out where does this flow break in your case.
> No mmc_send_relative_addr() does _not_ return -110, actually it
> is not called at all.
OK.
> I inserted a WARN_ON() in sdio_bus_probe, and here is the backtrace I get:
The interesting part is actually what happens after sdio_bus_probe(),
not before it.
Is mmc_power_restore_host being called ? mmc_sdio_power_restore ?
mmc_sdio_init_card ? etc...
I'm also attaching a patch that requires hosts to explicitly indicate
whether they support powering off/on their cards after boot (which
would prevent SDIO core from powering off you card after boot since
your host doesn't indicate that capability).
Can you please see if the problem goes away with it ?
Thanks,
Ohad.
From 6b5691bdd8184cc0876d209c69d38844ea10f678 Mon Sep 17 00:00:00 2001
From: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
Date: Mon, 1 Nov 2010 09:41:44 +0200
Subject: [PATCH] mmc: add MMC_CAP_RUNTIME_PM
Some board/card/host configurations are not capable of powering off/on
on the card during runtime.
To support such configurations, and to allow smoother transition to
runtime PM behavior, MMC_CAP_RUNTIME_PM is added, so hosts need to
explicitly indicate that it's OK to power off their cards after boot.
This will prevent sdio_bus_probe() from failing to power on the card
when the driver is loaded on such setups.
Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
---
drivers/mmc/core/sdio.c | 37 +++++++++++++++++++++++--------------
drivers/mmc/core/sdio_bus.c | 33 ++++++++++++++++++++++-----------
include/linux/mmc/host.h | 1 +
3 files changed, 46 insertions(+), 25 deletions(-)
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 6a9ad40..373d56d 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_RUNTIME_PM) {
+ err = pm_runtime_get_sync(&host->card->dev);
+ if (err < 0)
+ goto out;
+ }
mmc_claim_host(host);
@@ -570,7 +572,8 @@ out:
}
/* Tell PM core that we're done */
- pm_runtime_put(&host->card->dev);
+ if (host->caps & MMC_CAP_RUNTIME_PM)
+ pm_runtime_put(&host->card->dev);
}
/*
@@ -720,16 +723,21 @@ 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_RUNTIME_PM) {
+ /*
+ * 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
@@ -747,9 +755,10 @@ 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_RUNTIME_PM)
+ 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 2716c7a..f3ce21b 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_RUNTIME_PM) {
+ 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_RUNTIME_PM)
+ 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_RUNTIME_PM) {
+ 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_RUNTIME_PM)
+ 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_RUNTIME_PM)
+ 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_RUNTIME_PM)
+ pm_runtime_resume(dev);
return 0;
}
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index c3ffad8..e5eee0e 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -167,6 +167,7 @@ struct mmc_host {
/* DDR mode at 1.8V */
#define MMC_CAP_1_2V_DDR (1 << 12) /* can support */
/* DDR mode at 1.2V */
+#define MMC_CAP_RUNTIME_PM (1 << 13) /* Can power off/on in runtime */
mmc_pm_flag_t pm_caps; /* supported pm features */
--
1.7.0.4
