[v4,1/2] thermal: rcar_gen3_thermal: fix interrupt type
diff mbox series

Message ID 20190424051145.23072-2-jiada_wang@mentor.com
State Accepted
Delegated to: Eduardo Valentin
Headers show
Series
  • thermal: rcar_gen3_thermal: fix IRQ issues
Related show

Commit Message

Jiada Wang April 24, 2019, 5:11 a.m. UTC
Currently IRQF_SHARED type interrupt line is allocated, but it
is not appropriate, as the interrupt line isn't shared between
different devices, instead IRQF_ONESHOT is the proper type.

By changing interrupt type to IRQF_ONESHOT, now irq handler is
no longer needed, as clear of interrupt status can be done in
threaded interrupt context.

Because IRQF_ONESHOT type interrupt line is kept disabled until
the threaded handler has been run, so there is no need to protect
read/write of REG_GEN3_IRQSTR with lock.

Fixes: 7d4b269776ec6 ("enable hardware interrupts for trip points")
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/thermal/rcar_gen3_thermal.c | 38 +++++------------------------
 1 file changed, 6 insertions(+), 32 deletions(-)

Comments

Simon Horman April 24, 2019, 9:23 a.m. UTC | #1
On Wed, Apr 24, 2019 at 02:11:44PM +0900, Jiada Wang wrote:
> Currently IRQF_SHARED type interrupt line is allocated, but it
> is not appropriate, as the interrupt line isn't shared between
> different devices, instead IRQF_ONESHOT is the proper type.
> 
> By changing interrupt type to IRQF_ONESHOT, now irq handler is
> no longer needed, as clear of interrupt status can be done in
> threaded interrupt context.
> 
> Because IRQF_ONESHOT type interrupt line is kept disabled until
> the threaded handler has been run, so there is no need to protect
> read/write of REG_GEN3_IRQSTR with lock.
> 
> Fixes: 7d4b269776ec6 ("enable hardware interrupts for trip points")
> Signed-off-by: Jiada Wang <jiada_wang@mentor.com>


Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Daniel Lezcano April 24, 2019, 9:31 a.m. UTC | #2
On 24/04/2019 07:11, Jiada Wang wrote:
> Currently IRQF_SHARED type interrupt line is allocated, but it
> is not appropriate, as the interrupt line isn't shared between
> different devices, instead IRQF_ONESHOT is the proper type.
> 
> By changing interrupt type to IRQF_ONESHOT, now irq handler is
> no longer needed, as clear of interrupt status can be done in
> threaded interrupt context.
> 
> Because IRQF_ONESHOT type interrupt line is kept disabled until
> the threaded handler has been run, so there is no need to protect
> read/write of REG_GEN3_IRQSTR with lock.
> 
> Fixes: 7d4b269776ec6 ("enable hardware interrupts for trip points")
> Signed-off-by: Jiada Wang <jiada_wang@mentor.com>

Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org>

> ---
>  drivers/thermal/rcar_gen3_thermal.c | 38 +++++------------------------
>  1 file changed, 6 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c
> index 88fa41cf16e8..065e16f53285 100644
> --- a/drivers/thermal/rcar_gen3_thermal.c
> +++ b/drivers/thermal/rcar_gen3_thermal.c
> @@ -14,7 +14,6 @@
>  #include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
> -#include <linux/spinlock.h>
>  #include <linux/sys_soc.h>
>  #include <linux/thermal.h>
>  
> @@ -82,7 +81,6 @@ struct rcar_gen3_thermal_tsc {
>  struct rcar_gen3_thermal_priv {
>  	struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM];
>  	unsigned int num_tscs;
> -	spinlock_t lock; /* Protect interrupts on and off */
>  	void (*thermal_init)(struct rcar_gen3_thermal_tsc *tsc);
>  };
>  
> @@ -232,38 +230,16 @@ static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data)
>  {
>  	struct rcar_gen3_thermal_priv *priv = data;
>  	u32 status;
> -	int i, ret = IRQ_HANDLED;
> +	int i;
>  
> -	spin_lock(&priv->lock);
>  	for (i = 0; i < priv->num_tscs; i++) {
>  		status = rcar_gen3_thermal_read(priv->tscs[i], REG_GEN3_IRQSTR);
>  		rcar_gen3_thermal_write(priv->tscs[i], REG_GEN3_IRQSTR, 0);
>  		if (status)
> -			ret = IRQ_WAKE_THREAD;
> +			thermal_zone_device_update(priv->tscs[i]->zone,
> +						   THERMAL_EVENT_UNSPECIFIED);
>  	}
>  
> -	if (ret == IRQ_WAKE_THREAD)
> -		rcar_thermal_irq_set(priv, false);
> -
> -	spin_unlock(&priv->lock);
> -
> -	return ret;
> -}
> -
> -static irqreturn_t rcar_gen3_thermal_irq_thread(int irq, void *data)
> -{
> -	struct rcar_gen3_thermal_priv *priv = data;
> -	unsigned long flags;
> -	int i;
> -
> -	for (i = 0; i < priv->num_tscs; i++)
> -		thermal_zone_device_update(priv->tscs[i]->zone,
> -					   THERMAL_EVENT_UNSPECIFIED);
> -
> -	spin_lock_irqsave(&priv->lock, flags);
> -	rcar_thermal_irq_set(priv, true);
> -	spin_unlock_irqrestore(&priv->lock, flags);
> -
>  	return IRQ_HANDLED;
>  }
>  
> @@ -371,8 +347,6 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
>  	if (soc_device_match(r8a7795es1))
>  		priv->thermal_init = rcar_gen3_thermal_init_r8a7795es1;
>  
> -	spin_lock_init(&priv->lock);
> -
>  	platform_set_drvdata(pdev, priv);
>  
>  	/*
> @@ -390,9 +364,9 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
>  		if (!irqname)
>  			return -ENOMEM;
>  
> -		ret = devm_request_threaded_irq(dev, irq, rcar_gen3_thermal_irq,
> -						rcar_gen3_thermal_irq_thread,
> -						IRQF_SHARED, irqname, priv);
> +		ret = devm_request_threaded_irq(dev, irq, NULL,
> +						rcar_gen3_thermal_irq,
> +						IRQF_ONESHOT, irqname, priv);
>  		if (ret)
>  			return ret;
>  	}
>
Eugeniu Rosca April 24, 2019, 12:28 p.m. UTC | #3
On Wed, Apr 24, 2019 at 02:11:44PM +0900, Jiada Wang wrote:
> Currently IRQF_SHARED type interrupt line is allocated, but it
> is not appropriate, as the interrupt line isn't shared between
> different devices, instead IRQF_ONESHOT is the proper type.
> 
> By changing interrupt type to IRQF_ONESHOT, now irq handler is
> no longer needed, as clear of interrupt status can be done in
> threaded interrupt context.
> 
> Because IRQF_ONESHOT type interrupt line is kept disabled until
> the threaded handler has been run, so there is no need to protect
> read/write of REG_GEN3_IRQSTR with lock.
> 
> Fixes: 7d4b269776ec6 ("enable hardware interrupts for trip points")
> Signed-off-by: Jiada Wang <jiada_wang@mentor.com>

Based on https://patchwork.kernel.org/cover/10914079/#22603533 :

Reviewed-and-Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>

Thanks!

Patch
diff mbox series

diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c
index 88fa41cf16e8..065e16f53285 100644
--- a/drivers/thermal/rcar_gen3_thermal.c
+++ b/drivers/thermal/rcar_gen3_thermal.c
@@ -14,7 +14,6 @@ 
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
-#include <linux/spinlock.h>
 #include <linux/sys_soc.h>
 #include <linux/thermal.h>
 
@@ -82,7 +81,6 @@  struct rcar_gen3_thermal_tsc {
 struct rcar_gen3_thermal_priv {
 	struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM];
 	unsigned int num_tscs;
-	spinlock_t lock; /* Protect interrupts on and off */
 	void (*thermal_init)(struct rcar_gen3_thermal_tsc *tsc);
 };
 
@@ -232,38 +230,16 @@  static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data)
 {
 	struct rcar_gen3_thermal_priv *priv = data;
 	u32 status;
-	int i, ret = IRQ_HANDLED;
+	int i;
 
-	spin_lock(&priv->lock);
 	for (i = 0; i < priv->num_tscs; i++) {
 		status = rcar_gen3_thermal_read(priv->tscs[i], REG_GEN3_IRQSTR);
 		rcar_gen3_thermal_write(priv->tscs[i], REG_GEN3_IRQSTR, 0);
 		if (status)
-			ret = IRQ_WAKE_THREAD;
+			thermal_zone_device_update(priv->tscs[i]->zone,
+						   THERMAL_EVENT_UNSPECIFIED);
 	}
 
-	if (ret == IRQ_WAKE_THREAD)
-		rcar_thermal_irq_set(priv, false);
-
-	spin_unlock(&priv->lock);
-
-	return ret;
-}
-
-static irqreturn_t rcar_gen3_thermal_irq_thread(int irq, void *data)
-{
-	struct rcar_gen3_thermal_priv *priv = data;
-	unsigned long flags;
-	int i;
-
-	for (i = 0; i < priv->num_tscs; i++)
-		thermal_zone_device_update(priv->tscs[i]->zone,
-					   THERMAL_EVENT_UNSPECIFIED);
-
-	spin_lock_irqsave(&priv->lock, flags);
-	rcar_thermal_irq_set(priv, true);
-	spin_unlock_irqrestore(&priv->lock, flags);
-
 	return IRQ_HANDLED;
 }
 
@@ -371,8 +347,6 @@  static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 	if (soc_device_match(r8a7795es1))
 		priv->thermal_init = rcar_gen3_thermal_init_r8a7795es1;
 
-	spin_lock_init(&priv->lock);
-
 	platform_set_drvdata(pdev, priv);
 
 	/*
@@ -390,9 +364,9 @@  static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 		if (!irqname)
 			return -ENOMEM;
 
-		ret = devm_request_threaded_irq(dev, irq, rcar_gen3_thermal_irq,
-						rcar_gen3_thermal_irq_thread,
-						IRQF_SHARED, irqname, priv);
+		ret = devm_request_threaded_irq(dev, irq, NULL,
+						rcar_gen3_thermal_irq,
+						IRQF_ONESHOT, irqname, priv);
 		if (ret)
 			return ret;
 	}