[PATCH v2 3/3] mmc: use non-reentrant workqueue for clock gating

From: Mika Westerberg
Date: Thu Aug 18 2011 - 08:23:26 EST


The default multithread workqueue can cause the same work to be executed
concurrently on a different CPUs. This isn't really suitable for clock
gating as it might already gated the clock and gating it twice results both
host->clk_old and host->ios.clock to be set to 0.

To prevent this from happening we use system_nrt_wq instead.

Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/mmc/core/host.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 96a26b2..793d0a0 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -179,7 +179,7 @@ void mmc_host_clk_release(struct mmc_host *host)
host->clk_requests--;
if (mmc_host_may_gate_card(host->card) &&
!host->clk_requests)
- schedule_work(&host->clk_gate_work);
+ queue_work(system_nrt_wq, &host->clk_gate_work);
spin_unlock_irqrestore(&host->clk_lock, flags);
}

--
1.7.5.4

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