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authorUlf Hansson <ulf.hansson@stericsson.com>2012-04-19 11:55:25 +0200
committerChris Ball <cjb@laptop.org>2012-04-20 21:52:13 -0400
commit7c5709194096beea1ab6e6db46768d70a068efb0 (patch)
tree4f41be93cdcbaaeb32869c1a1e5e60f3597a6261
parente1631f989e0c6c8d9b43a2dbdd1097f70da603a5 (diff)
mmc: core: Do not pre-claim host in suspend
Since SDIO drivers may want to do some SDIO operations in their suspend callback functions, we must not keep the host claimed when calling them. Daniel Drake reported that libertas_sdio encountered a deadlock in its suspend function. Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com> Tested-by: Daniel Drake <dsd@laptop.org> [stable@: please apply to 3.2-stable and 3.3-stable] Cc: stable <stable@vger.kernel.org> Signed-off-by: Chris Ball <cjb@laptop.org>
-rw-r--r--drivers/mmc/core/core.c55
1 files changed, 20 insertions, 35 deletions
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index e541efbf3256..ba821fe70bca 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2238,6 +2238,7 @@ int mmc_cache_ctrl(struct mmc_host *host, u8 enable)
mmc_card_is_removable(host))
return err;
+ mmc_claim_host(host);
if (card && mmc_card_mmc(card) &&
(card->ext_csd.cache_size > 0)) {
enable = !!enable;
@@ -2255,6 +2256,7 @@ int mmc_cache_ctrl(struct mmc_host *host, u8 enable)
card->ext_csd.cache_ctrl = enable;
}
}
+ mmc_release_host(host);
return err;
}
@@ -2272,49 +2274,32 @@ int mmc_suspend_host(struct mmc_host *host)
cancel_delayed_work(&host->detect);
mmc_flush_scheduled_work();
- if (mmc_try_claim_host(host)) {
- err = mmc_cache_ctrl(host, 0);
- mmc_release_host(host);
- } else {
- err = -EBUSY;
- }
+ err = mmc_cache_ctrl(host, 0);
if (err)
goto out;
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
- /*
- * A long response time is not acceptable for device drivers
- * when doing suspend. Prevent mmc_claim_host in the suspend
- * sequence, to potentially wait "forever" by trying to
- * pre-claim the host.
- */
- if (mmc_try_claim_host(host)) {
- if (host->bus_ops->suspend) {
- err = host->bus_ops->suspend(host);
- }
- mmc_release_host(host);
+ 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. (Calling
- * bus_ops->remove() with a claimed host can
- * deadlock.)
- */
- if (host->bus_ops->remove)
- host->bus_ops->remove(host);
- mmc_claim_host(host);
- mmc_detach_bus(host);
- mmc_power_off(host);
- mmc_release_host(host);
- host->pm_flags = 0;
- err = 0;
- }
- } else {
- err = -EBUSY;
+ if (err == -ENOSYS || !host->bus_ops->resume) {
+ /*
+ * We simply "remove" the card in this case.
+ * It will be redetected on resume. (Calling
+ * bus_ops->remove() with a claimed host can
+ * deadlock.)
+ */
+ if (host->bus_ops->remove)
+ host->bus_ops->remove(host);
+ mmc_claim_host(host);
+ mmc_detach_bus(host);
+ mmc_power_off(host);
+ mmc_release_host(host);
+ host->pm_flags = 0;
+ err = 0;
}
}
mmc_bus_put(host);