thermal: rcar: use mutex lock instead of spin lock

Current R-Car thermal driver is using spin lock for each
registers read/write, but it is pointless lock.
This lock is required while reading temperature,
but it needs long wait (= 300ms).
So, this patch used mutex lock while reading temperature,
instead of spin lock for each registers.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
This commit is contained in:
Kuninori Morimoto 2013-01-31 09:03:22 +00:00 committed by Zhang Rui
parent f8f53e1874
commit b2bbc6a2ac

View File

@ -42,7 +42,7 @@
struct rcar_thermal_priv {
void __iomem *base;
struct device *dev;
spinlock_t lock;
struct mutex lock;
};
#define MCELSIUS(temp) ((temp) * 1000)
@ -54,46 +54,26 @@ struct rcar_thermal_priv {
*/
static u32 rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg)
{
unsigned long flags;
u32 ret;
spin_lock_irqsave(&priv->lock, flags);
ret = ioread32(priv->base + reg);
spin_unlock_irqrestore(&priv->lock, flags);
return ret;
return ioread32(priv->base + reg);
}
#if 0 /* no user at this point */
static void rcar_thermal_write(struct rcar_thermal_priv *priv,
u32 reg, u32 data)
{
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
iowrite32(data, priv->base + reg);
spin_unlock_irqrestore(&priv->lock, flags);
}
#endif
static void rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg,
u32 mask, u32 data)
{
unsigned long flags;
u32 val;
spin_lock_irqsave(&priv->lock, flags);
val = ioread32(priv->base + reg);
val &= ~mask;
val |= (data & mask);
iowrite32(val, priv->base + reg);
spin_unlock_irqrestore(&priv->lock, flags);
}
/*
@ -107,6 +87,8 @@ static int rcar_thermal_get_temp(struct thermal_zone_device *zone,
int i;
int ctemp, old, new;
mutex_lock(&priv->lock);
/*
* TSC decides a value of CPTAP automatically,
* and this is the conditions which validate interrupt.
@ -138,6 +120,8 @@ static int rcar_thermal_get_temp(struct thermal_zone_device *zone,
*temp = MCELSIUS((ctemp * 5) - 65);
mutex_unlock(&priv->lock);
return 0;
}
@ -225,7 +209,7 @@ static int rcar_thermal_probe(struct platform_device *pdev)
}
priv->dev = &pdev->dev;
spin_lock_init(&priv->lock);
mutex_init(&priv->lock);
priv->base = devm_ioremap_nocache(&pdev->dev,
res->start, resource_size(res));
if (!priv->base) {