From 758b8cc02fae512d6748a87d1c8656a94b1fecaa Mon Sep 17 00:00:00 2001 From: Chris Ball Date: Mon, 16 May 2011 11:32:26 -0400 Subject: Revert "mmc: fix a race between card-detect rescan and clock-gate work instances" commit 86f315bbb2374f1f077500ad131dd9b71856e697 upstream. This reverts commit 26fc8775b51484d8c0a671198639c6d5ae60533e, which has been reported to cause boot/resume-time crashes for some users: https://bbs.archlinux.org/viewtopic.php?id=118751. Signed-off-by: Chris Ball Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/core/host.c | 9 +++++---- include/linux/mmc/host.h | 1 + 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 9ae3dbfba36..b3ac6c5bc5c 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -94,7 +94,7 @@ static void mmc_host_clk_gate_delayed(struct mmc_host *host) spin_unlock_irqrestore(&host->clk_lock, flags); return; } - mmc_claim_host(host); + mutex_lock(&host->clk_gate_mutex); spin_lock_irqsave(&host->clk_lock, flags); if (!host->clk_requests) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -104,7 +104,7 @@ static void mmc_host_clk_gate_delayed(struct mmc_host *host) pr_debug("%s: gated MCI clock\n", mmc_hostname(host)); } spin_unlock_irqrestore(&host->clk_lock, flags); - mmc_release_host(host); + mutex_unlock(&host->clk_gate_mutex); } /* @@ -130,7 +130,7 @@ void mmc_host_clk_ungate(struct mmc_host *host) { unsigned long flags; - mmc_claim_host(host); + mutex_lock(&host->clk_gate_mutex); spin_lock_irqsave(&host->clk_lock, flags); if (host->clk_gated) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -140,7 +140,7 @@ void mmc_host_clk_ungate(struct mmc_host *host) } host->clk_requests++; spin_unlock_irqrestore(&host->clk_lock, flags); - mmc_release_host(host); + mutex_unlock(&host->clk_gate_mutex); } /** @@ -218,6 +218,7 @@ static inline void mmc_host_clk_init(struct mmc_host *host) host->clk_gated = false; INIT_WORK(&host->clk_gate_work, mmc_host_clk_gate_work); spin_lock_init(&host->clk_lock); + mutex_init(&host->clk_gate_mutex); } /** diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index eb792cb6d74..bcb793ec737 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -183,6 +183,7 @@ struct mmc_host { struct work_struct clk_gate_work; /* delayed clock gate */ unsigned int clk_old; /* old clock value cache */ spinlock_t clk_lock; /* lock for clk fields */ + struct mutex clk_gate_mutex; /* mutex for clock gating */ #endif /* host specific block data */ -- cgit v1.2.3