From: Stanislav Meduna <stanislav.med...@nxtcontrol.com>
On a TQMa53 module the mmc_sleep leaves the eMMC card in a state
that the imx53 rom boot code is unable to probe, resulting in
reboot hanging. Add a device tree property to disable sleeping
on suspend.
For TQMa53 modules the exact commit to cause hang after reboot
(v3.10 -> v3.11):
commit 486fdbbc1483 ("mmc: core: Add shutdown callback for (e)MMC bus_ops")
[The exact discussion can be found here:
https://patchwork.kernel.org/patch/8881401/
"i.MX53 restart via watchdog does not work"
Signed-off-by: Stanislav Meduna <stanislav.med...@nxtcontrol.com>
Signed-off-by: Lukasz Majewski <lu...@denx.de>
---
Documentation/devicetree/bindings/mmc/mmc-card.txt | 4 ++++
drivers/mmc/core/mmc.c | 7 +++++--
include/linux/mmc/card.h | 2 +-
3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/mmc/mmc-card.txt
b/Documentation/devicetree/bindings/mmc/mmc-card.txt
index 8d2d71758907..c3ee151edd7c 100644
--- a/Documentation/devicetree/bindings/mmc/mmc-card.txt
+++ b/Documentation/devicetree/bindings/mmc/mmc-card.txt
@@ -12,6 +12,9 @@ Required properties:
Optional properties:
-broken-hpi : Use this to indicate that the mmc-card has a broken hpi
implementation, and that hpi should not be used
+-no-sleep-on-suspend : Do not put the card to sleep when suspending.
+ There are boards with bootloaders that are unable
+ to probe such card when rebooting.
Example:
@@ -26,5 +29,6 @@ Example:
reg = <0>;
compatible = "mmc-card";
broken-hpi;
+ no-sleep-on-suspend;
};
};
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 208a762b87ef..a3b74b5c8893 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -381,8 +381,11 @@ static int mmc_decode_ext_csd(struct mmc_card *card, u8
*ext_csd)
}
np = mmc_of_find_child_device(card->host, 0);
- if (np && of_device_is_compatible(np, "mmc-card"))
+ if (np && of_device_is_compatible(np, "mmc-card")) {
broken_hpi = of_property_read_bool(np, "broken-hpi");
+ card->no_sleep_on_suspend =
+ of_property_read_bool(np, "no-sleep-on-suspend");
+ }
of_node_put(np);
/*
@@ -1990,7 +1993,7 @@ static int _mmc_suspend(struct mmc_host *host, bool
is_suspend)
if (mmc_can_poweroff_notify(host->card) &&
((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend))
err = mmc_poweroff_notify(host->card, notify_type);
- else if (mmc_can_sleep(host->card))
+ else if (mmc_can_sleep(host->card) && !host->card->no_sleep_on_suspend)
err = mmc_sleep(host);
else if (!mmc_host_is_spi(host))
err = mmc_deselect_cards(host);
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 279b39008a33..c64d88e6de3b 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -304,8 +304,8 @@ struct mmc_card {
struct dentry *debugfs_root;
struct mmc_part part[MMC_NUM_PHY_PARTITION]; /* physical partitions */
unsigned int nr_parts;
-
unsigned int bouncesz; /* Bounce buffer size */
+ bool no_sleep_on_suspend;
};
static inline bool mmc_large_sector(struct mmc_card *card)
--
2.11.0
