| Message ID | 20190423141414.24264-2-jiada_wang@mentor.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Delegated to: | Eduardo Valentin |
| Headers | show |
| Series | thermal: rcar_gen3_thermal: fix IRQ issues | expand |
Hi Jiada, On Tue, Apr 23, 2019 at 11:14:13PM +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. > > Signed-off-by: Jiada Wang <jiada_wang@mentor.com> > --- > drivers/thermal/rcar_gen3_thermal.c | 34 +++++------------------------ > 1 file changed, 6 insertions(+), 28 deletions(-) > > diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c > index 88fa41cf16e8..ebbaef5a3cf1 100644 > --- a/drivers/thermal/rcar_gen3_thermal.c > +++ b/drivers/thermal/rcar_gen3_thermal.c > @@ -231,39 +231,17 @@ static void rcar_thermal_irq_set(struct rcar_gen3_thermal_priv *priv, bool on) > static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data) > { > struct rcar_gen3_thermal_priv *priv = data; > + int i; > u32 status; > - int i, ret = IRQ_HANDLED; nit: why not keeping 'int i' on the same line? > > - spin_lock(&priv->lock); [..] > - spin_unlock(&priv->lock); [..] > - spin_lock_irqsave(&priv->lock, flags); [..] > - spin_unlock_irqrestore(&priv->lock, flags); [..] FWIW, after applying the patch, the 'spinlock_t lock' member of 'struct rcar_gen3_thermal_priv' is no longer used in the driver, except to initialize it in probe. Is there any usage expected in future or should it be zapped?
On 23/04/2019 16:14, 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. > > Signed-off-by: Jiada Wang <jiada_wang@mentor.com> Fixes: 7d4b269776ec6 ("enable hardware interrupts for trip points") Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > drivers/thermal/rcar_gen3_thermal.c | 34 +++++------------------------ > 1 file changed, 6 insertions(+), 28 deletions(-) > > diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c > index 88fa41cf16e8..ebbaef5a3cf1 100644 > --- a/drivers/thermal/rcar_gen3_thermal.c > +++ b/drivers/thermal/rcar_gen3_thermal.c > @@ -231,39 +231,17 @@ static void rcar_thermal_irq_set(struct rcar_gen3_thermal_priv *priv, bool on) > static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data) > { > struct rcar_gen3_thermal_priv *priv = data; > + int i; > u32 status; > - int i, ret = IRQ_HANDLED; > > - 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; > } > > @@ -390,9 +368,9 @@ 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; > } >
diff --git a/drivers/thermal/rcar_gen3_thermal.c b/drivers/thermal/rcar_gen3_thermal.c index 88fa41cf16e8..ebbaef5a3cf1 100644 --- a/drivers/thermal/rcar_gen3_thermal.c +++ b/drivers/thermal/rcar_gen3_thermal.c @@ -231,39 +231,17 @@ static void rcar_thermal_irq_set(struct rcar_gen3_thermal_priv *priv, bool on) static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data) { struct rcar_gen3_thermal_priv *priv = data; + int i; u32 status; - int i, ret = IRQ_HANDLED; - 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; } @@ -390,9 +368,9 @@ 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; }
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. Signed-off-by: Jiada Wang <jiada_wang@mentor.com> --- drivers/thermal/rcar_gen3_thermal.c | 34 +++++------------------------ 1 file changed, 6 insertions(+), 28 deletions(-)