[PATCH v4 07/19] clocksource: sh_mtu2: Replace global spinlock with a per-device spinlock
From: laurent.pinchart+renesas@ideasonboard.com (Laurent Pinchart)
Date: 2014-06-16 15:07:19
Also in:
linux-sh
Subsystem:
clocksource, clockevent drivers, the rest · Maintainers:
Daniel Lezcano, Thomas Gleixner, Linus Torvalds
The global spinlock is used to protect the shared start/stop register. Now that all MTU2 channels are handled by a single device instance, use a per-device spinlock. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Tested-by: Wolfram Sang <redacted> --- drivers/clocksource/sh_mtu2.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/clocksource/sh_mtu2.c b/drivers/clocksource/sh_mtu2.c
index 2931fea..ebdf9d1 100644
--- a/drivers/clocksource/sh_mtu2.c
+++ b/drivers/clocksource/sh_mtu2.c@@ -47,14 +47,14 @@ struct sh_mtu2_device { void __iomem *mapbase; struct clk *clk; + raw_spinlock_t lock; /* Protect the shared registers */ + struct sh_mtu2_channel *channels; unsigned int num_channels; bool has_clockevent; }; -static DEFINE_RAW_SPINLOCK(sh_mtu2_lock); - #define TSTR -1 /* shared register */ #define TCR 0 /* channel register */ #define TMDR 1 /* channel register */
@@ -192,7 +192,7 @@ static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start) unsigned long flags, value; /* start stop register shared by multiple timer channels */ - raw_spin_lock_irqsave(&sh_mtu2_lock, flags); + raw_spin_lock_irqsave(&ch->mtu->lock, flags); value = sh_mtu2_read(ch, TSTR); if (start)
@@ -201,7 +201,7 @@ static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start) value &= ~(1 << ch->index); sh_mtu2_write(ch, TSTR, value); - raw_spin_unlock_irqrestore(&sh_mtu2_lock, flags); + raw_spin_unlock_irqrestore(&ch->mtu->lock, flags); } static int sh_mtu2_enable(struct sh_mtu2_channel *ch)
@@ -402,6 +402,8 @@ static int sh_mtu2_setup(struct sh_mtu2_device *mtu, mtu->pdev = pdev; + raw_spin_lock_init(&mtu->lock); + /* Get hold of clock. */ mtu->clk = clk_get(&mtu->pdev->dev, "fck"); if (IS_ERR(mtu->clk)) {
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1.8.5.5