Commit 86f315bb authored by Chris Ball's avatar Chris Ball
Browse files

Revert "mmc: fix a race between card-detect rescan and clock-gate work instances" 

This reverts commit 26fc8775, which has
been reported to cause boot/resume-time crashes for some users:

https://bbs.archlinux.org/viewtopic.php?id=118751

.

Signed-off-by: default avatarChris Ball <cjb@laptop.org>
Cc: <stable@kernel.org>
parent eed631e0

drivers/mmc/core/host.c

+5 −4
Original line number Diff line number Diff line
@@ -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);

}



/**
@@ -215,6 +215,7 @@ 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);

}



/**

include/linux/mmc/host.h

+1 −0
Original line number Diff line number Diff line
@@ -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 */