clocksource: sh_cmt: Replace global spinlock with a per-device spinlock

The global spinlock is used to protect the shared start/stop register.
Now that all CMT 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: Simon Horman <horms+renesas@verge.net.au>

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index fcd38db9ce5c..190c655d8352 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -118,6 +118,8 @@ struct sh_cmt_device {
         void __iomem *mapbase;
         struct clk *clk;
 
+        raw_spinlock_t lock; /* Protect the shared start/stop register */
+
         struct sh_cmt_channel *channels;
         unsigned int num_channels;
 
@@ -299,14 +301,12 @@ static unsigned long sh_cmt_get_counter(struct sh_cmt_channel *ch,
         return v2;
 }
 
-static DEFINE_RAW_SPINLOCK(sh_cmt_lock);
-
 static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
 {
         unsigned long flags, value;
 
         /* start stop register shared by multiple timer channels */
-        raw_spin_lock_irqsave(&sh_cmt_lock, flags);
+        raw_spin_lock_irqsave(&ch->cmt->lock, flags);
         value = sh_cmt_read_cmstr(ch);
 
         if (start)
@@ -315,7 +315,7 @@ static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
                 value &= ~(1 << ch->timer_bit);
 
         sh_cmt_write_cmstr(ch, value);
-        raw_spin_unlock_irqrestore(&sh_cmt_lock, flags);
+        raw_spin_unlock_irqrestore(&ch->cmt->lock, flags);
 }
 
 static int sh_cmt_enable(struct sh_cmt_channel *ch, unsigned long *rate)
@@ -934,6 +934,7 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
 
         memset(cmt, 0, sizeof(*cmt));
         cmt->pdev = pdev;
+        raw_spin_lock_init(&cmt->lock);
 
         if (!cfg) {
                 dev_err(&cmt->pdev->dev, "missing platform data\n");