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 it's suspend function.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxxxxxx>
---
drivers/mmc/core/core.c | 55 +++++++++++++++++-----------------------------
1 files changed, 20 insertions(+), 35 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index e541efb..ba821fe 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);
--
1.7.9
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