[Lucid] pull-request: mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume
Lee Jones
lee.jones at canonical.com
Fri Sep 3 12:13:51 UTC 2010
This patch fixes:
BugLink: http://bugs.launchpad.net/bugs/477106
The following changes since commit 5470af5fd104192214b496a2736fd26200f4650d:
Steve Conklin (1):
UBUNTU: [Config] updateconfigs
are available in the git repository at:
git://kernel.ubuntu.com/lag/ubuntu-lucid.git lp477106
Lee Jones (1):
mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume
drivers/mmc/core/core.c | 87 ++++++++++++++++++++++++++++++++--------------
drivers/mmc/core/host.c | 5 +++
include/linux/mmc/host.h | 6 +++
include/linux/mmc/pm.h | 30 ++++++++++++++++
4 files changed, 102 insertions(+), 26 deletions(-)
create mode 100644 include/linux/mmc/pm.h
------------------------------------------------------------------------
commit f8a01342978bcf0749b4ca27268deb47d3559261
Author: Lee Jones <lee.jones at canonical.com>
Date: Fri Sep 3 12:42:15 2010 +0100
mmc: fix all hangs related to mmc/sd card insert/removal during suspend/resume
Based on a patch-set originally written by Maxim Levitsky.
If you don't use CONFIG_MMC_UNSAFE_RESUME, as soon as you attempt to
suspend, the card will be removed, therefore this patch doesn't change the
behavior of this option.
However the removal will be done by pm notifier, which runs while
userspace is still not frozen and thus can freely use del_gendisk, without
the risk of deadlock which would happen otherwise.
Card detect workqueue is now disabled while userspace is frozen, Therefore
if you do use CONFIG_MMC_UNSAFE_RESUME, and remove the card during
suspend, the removal will be detected as soon as userspace is unfrozen,
again at the moment it is safe to call del_gendisk.
Tested with and without CONFIG_MMC_UNSAFE_RESUME with suspend and hibernate.
[akpm at linux-foundation.org: clean up function prototype]
[akpm at linux-foundation.org: fix CONFIG_PM-n linkage, small cleanups]
[akpm at linux-foundation.org: coding-style fixes]
Signed-off-by: Maxim Levitsky <maximlevitsky at gmail.com>
Cc: David Brownell <david-b at pacbell.net>
Cc: Alan Stern <stern at rowland.harvard.edu>
Cc: <linux-mmc at vger.kernel.org>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
[Backported to Ubuntu-2.6.32-25.43 by Lee Jones]
Signed-off-by: Lee Jones <lee.jones at canonical.com>
BugLink: http://bugs.launchpad.net/bugs/477106
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 30acd52..2479abe 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -106,8 +106,9 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
cmd->error = 0;
host->ops->request(host, mrq);
} else {
+#ifdef CONFIG_LEDS_TRIGGERS
led_trigger_event(host->led, LED_OFF);
-
+#endif
pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
mmc_hostname(host), cmd->opcode, err,
cmd->resp[0], cmd->resp[1],
@@ -163,7 +164,9 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
WARN_ON(!host->claimed);
+#ifdef CONFIG_LEDS_TRIGGERS
led_trigger_event(host->led, LED_FULL);
+#endif
mrq->cmd->error = 0;
mrq->cmd->mrq = mrq;
@@ -1057,6 +1060,17 @@ void mmc_rescan(struct work_struct *work)
container_of(work, struct mmc_host, detect.work);
u32 ocr;
int err;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (host->rescan_disable) {
+ spin_unlock_irqrestore(&host->lock, flags);
+ return;
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
mmc_bus_get(host);
@@ -1263,18 +1277,6 @@ int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
if (host->bus_ops && !host->bus_dead) {
if (host->bus_ops->suspend)
err = host->bus_ops->suspend(host);
- if (err == -ENOSYS || !host->bus_ops->resume) {
- /*
- * We simply "remove" the card in this case.
- * It will be redetected on resume.
- */
- if (host->bus_ops->remove)
- host->bus_ops->remove(host);
- mmc_claim_host(host);
- mmc_detach_bus(host);
- mmc_release_host(host);
- err = 0;
- }
}
mmc_bus_put(host);
@@ -1304,28 +1306,61 @@ int mmc_resume_host(struct mmc_host *host)
printk(KERN_WARNING "%s: error %d during resume "
"(card was removed?)\n",
mmc_hostname(host), err);
- if (host->bus_ops->remove)
- host->bus_ops->remove(host);
- mmc_claim_host(host);
- mmc_detach_bus(host);
- mmc_release_host(host);
- /* no need to bother upper layers */
err = 0;
}
}
mmc_bus_put(host);
- /*
- * We add a slight delay here so that resume can progress
- * in parallel.
- */
- mmc_detect_change(host, 1);
-
return err;
}
-
EXPORT_SYMBOL(mmc_resume_host);
+/* Do the card removal on suspend if card is assumed removeable
+ * Do that in pm notifier while userspace isn't yet frozen, so we will be able
+ to sync the card.
+*/
+int mmc_pm_notify(struct notifier_block *notify_block,
+ unsigned long mode, void *unused)
+{
+ struct mmc_host *host = container_of(
+ notify_block, struct mmc_host, pm_notify);
+ unsigned long flags;
+
+
+ switch (mode) {
+ case PM_HIBERNATION_PREPARE:
+ case PM_SUSPEND_PREPARE:
+
+ spin_lock_irqsave(&host->lock, flags);
+ host->rescan_disable = 1;
+ spin_unlock_irqrestore(&host->lock, flags);
+ cancel_delayed_work_sync(&host->detect);
+
+ if (!host->bus_ops || host->bus_ops->suspend)
+ break;
+
+ mmc_claim_host(host);
+
+ if (host->bus_ops->remove)
+ host->bus_ops->remove(host);
+
+ mmc_detach_bus(host);
+ mmc_release_host(host);
+ host->pm_flags = 0;
+ break;
+
+ case PM_POST_SUSPEND:
+ case PM_POST_HIBERNATION:
+
+ spin_lock_irqsave(&host->lock, flags);
+ host->rescan_disable = 0;
+ spin_unlock_irqrestore(&host->lock, flags);
+ mmc_detect_change(host, 0);
+
+ }
+
+ return 0;
+}
#endif
static int __init mmc_init(void)
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index a268d12..0efe631 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -16,6 +16,8 @@
#include <linux/idr.h>
#include <linux/pagemap.h>
#include <linux/leds.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
#include <linux/mmc/host.h>
@@ -84,6 +86,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
init_waitqueue_head(&host->wq);
INIT_DELAYED_WORK(&host->detect, mmc_rescan);
INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable);
+ host->pm_notify.notifier_call = mmc_pm_notify;
/*
* By default, hosts do not support SGIO or large requests.
@@ -132,6 +135,7 @@ int mmc_add_host(struct mmc_host *host)
#endif
mmc_start_host(host);
+ register_pm_notifier(&host->pm_notify);
return 0;
}
@@ -148,6 +152,7 @@ EXPORT_SYMBOL(mmc_add_host);
*/
void mmc_remove_host(struct mmc_host *host)
{
+ unregister_pm_notifier(&host->pm_notify);
mmc_stop_host(host);
#ifdef CONFIG_DEBUG_FS
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index eaf3636..c43bc21 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -14,6 +14,7 @@
#include <linux/sched.h>
#include <linux/mmc/core.h>
+#include <linux/mmc/pm.h>
struct mmc_ios {
unsigned int clock; /* clock rate */
@@ -120,6 +121,7 @@ struct mmc_host {
unsigned int f_min;
unsigned int f_max;
u32 ocr_avail;
+ struct notifier_block pm_notify;
#define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - 1.95 */
#define MMC_VDD_20_21 0x00000100 /* VDD voltage 2.0 ~ 2.1 */
@@ -177,6 +179,7 @@ struct mmc_host {
/* Only used with MMC_CAP_DISABLE */
int enabled; /* host is enabled */
+ int rescan_disable; /* disable card detection */
int nesting_cnt; /* "enable" nesting count */
int en_dis_recurs; /* detect recursion */
unsigned int disable_delay; /* disable delay in msecs */
@@ -197,6 +200,8 @@ struct mmc_host {
struct task_struct *sdio_irq_thread;
atomic_t sdio_irq_thread_abort;
+ mmc_pm_flag_t pm_flags; /* requested pm features */
+
#ifdef CONFIG_LEDS_TRIGGERS
struct led_trigger *led; /* activity led */
#endif
@@ -249,6 +254,7 @@ int mmc_card_can_sleep(struct mmc_host *host);
int mmc_host_enable(struct mmc_host *host);
int mmc_host_disable(struct mmc_host *host);
int mmc_host_lazy_disable(struct mmc_host *host);
+int mmc_pm_notify(struct notifier_block *notify_block, unsigned long, void *);
static inline void mmc_set_disable_delay(struct mmc_host *host,
unsigned int disable_delay)
diff --git a/include/linux/mmc/pm.h b/include/linux/mmc/pm.h
new file mode 100644
index 0000000..d37aac4
--- /dev/null
+++ b/include/linux/mmc/pm.h
@@ -0,0 +1,30 @@
+/*
+ * linux/include/linux/mmc/pm.h
+ *
+ * Author: Nicolas Pitre
+ * Copyright: (C) 2009 Marvell Technology Group Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef LINUX_MMC_PM_H
+#define LINUX_MMC_PM_H
+
+/*
+ * These flags are used to describe power management features that
+ * some cards (typically SDIO cards) might wish to benefit from when
+ * the host system is being suspended. There are several layers of
+ * abstractions involved, from the host controller driver, to the MMC core
+ * code, to the SDIO core code, to finally get to the actual SDIO function
+ * driver. This file is therefore used for common definitions shared across
+ * all those layers.
+ */
+
+typedef unsigned int mmc_pm_flag_t;
+
+#define MMC_PM_KEEP_POWER (1 << 0) /* preserve card power during suspend */
+#define MMC_PM_WAKE_SDIO_IRQ (1 << 1) /* wake up host system on SDIO IRQ assertion */
+
+#endif
More information about the kernel-team
mailing list