[RFC,07/14] genirq: Introduce irq_chip_get/set_parent_state calls
diff mbox series

Message ID 20190829181203.2660-8-ilina@codeaurora.org
State New
Headers show
Series
  • qcom: support wakeup capable GPIOs
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Commit Message

Lina Iyer Aug. 29, 2019, 6:11 p.m. UTC
From: Maulik Shah <mkshah@codeaurora.org>

On certain QTI chipsets some GPIOs are direct-connect interrupts
to the GIC.

Even when GPIOs are not used for interrupt generation and interrupt
line is disabled, it does not prevent interrupt to get pending at
GIC_ISPEND. When drivers call enable_irq unwanted interrupt occures.

Introduce irq_chip_get/set_parent_state calls to clear pending irq
which can get called within irq_enable of child irq chip to clear
any pending irq before enabling.

Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
---
 include/linux/irq.h |  6 ++++++
 kernel/irq/chip.c   | 44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)

Comments

Stephen Boyd Sept. 6, 2019, 12:35 a.m. UTC | #1
Quoting Lina Iyer (2019-08-29 11:11:56)
> From: Maulik Shah <mkshah@codeaurora.org>
> 
> On certain QTI chipsets some GPIOs are direct-connect interrupts
> to the GIC.
> 
> Even when GPIOs are not used for interrupt generation and interrupt
> line is disabled, it does not prevent interrupt to get pending at
> GIC_ISPEND. When drivers call enable_irq unwanted interrupt occures.

Inidicate functions with parenthesis like enable_irq().

> 
> Introduce irq_chip_get/set_parent_state calls to clear pending irq
> which can get called within irq_enable of child irq chip to clear
> any pending irq before enabling.

This sentence is hard to read.

> 
> index b76703b2c0af..6bb5b22bb0a7 100644
> --- a/kernel/irq/chip.c
> +++ b/kernel/irq/chip.c
> @@ -1297,6 +1297,50 @@ EXPORT_SYMBOL_GPL(handle_fasteoi_mask_irq);
>  
>  #endif /* CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS */
>  
> +/**
> + *     irq_chip_set_parent_state - set the state of a parent interrupt.
> + *     @data: Pointer to interrupt specific data
> + *     @which: State to be restored (one of IRQCHIP_STATE_*)
> + *     @val: Value corresponding to @which
> + *
> + */
> +int irq_chip_set_parent_state(struct irq_data *data,
> +                             enum irqchip_irq_state which,
> +                             bool val)
> +{
> +       data = data->parent_data;
> +       if (!data)
> +               return 0;
> +
> +       if (data->chip->irq_set_irqchip_state)
> +               return data->chip->irq_set_irqchip_state(data, which, val);
> +
> +       return 0;

How about 

	if (!data || !data->chip->irq_set_irqchip_state)
		return 0;
	
	return data->chip->irq_set_irqchip_state(...)

> +}
> +EXPORT_SYMBOL(irq_chip_set_parent_state);
> +
> +/**
> + *     irq_chip_get_parent_state - get the state of a parent interrupt.

Why is this indented so much?

> + *     @data: Pointer to interrupt specific data
> + *     @which: one of IRQCHIP_STATE_* the caller wants to know
> + *     @state: a pointer to a boolean where the state is to be stored
> + *

Document return value?

> + */
> +int irq_chip_get_parent_state(struct irq_data *data,
> +                             enum irqchip_irq_state which,
> +                             bool *state)
> +{
> +       data = data->parent_data;
> +       if (!data)
> +               return 0;
> +
> +       if (data->chip->irq_get_irqchip_state)
> +               return data->chip->irq_get_irqchip_state(data, which, state);
> +

Same comment here about collapsing logic.

> +       return 0;
> +}
> +EXPORT_SYMBOL(irq_chip_get_parent_state);

Please make these symbols _GPL.

> +
>  /**
>   * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
>   * NULL)

Patch
diff mbox series

diff --git a/include/linux/irq.h b/include/linux/irq.h
index fb301cf29148..7853eb9301f2 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -610,6 +610,12 @@  extern int irq_chip_pm_put(struct irq_data *data);
 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
 extern void handle_fasteoi_ack_irq(struct irq_desc *desc);
 extern void handle_fasteoi_mask_irq(struct irq_desc *desc);
+extern int irq_chip_set_parent_state(struct irq_data *data,
+				     enum irqchip_irq_state which,
+				     bool val);
+extern int irq_chip_get_parent_state(struct irq_data *data,
+				     enum irqchip_irq_state which,
+				     bool *state);
 extern void irq_chip_enable_parent(struct irq_data *data);
 extern void irq_chip_disable_parent(struct irq_data *data);
 extern void irq_chip_ack_parent(struct irq_data *data);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index b76703b2c0af..6bb5b22bb0a7 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -1297,6 +1297,50 @@  EXPORT_SYMBOL_GPL(handle_fasteoi_mask_irq);
 
 #endif /* CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS */
 
+/**
+ *	irq_chip_set_parent_state - set the state of a parent interrupt.
+ *	@data: Pointer to interrupt specific data
+ *	@which: State to be restored (one of IRQCHIP_STATE_*)
+ *	@val: Value corresponding to @which
+ *
+ */
+int irq_chip_set_parent_state(struct irq_data *data,
+			      enum irqchip_irq_state which,
+			      bool val)
+{
+	data = data->parent_data;
+	if (!data)
+		return 0;
+
+	if (data->chip->irq_set_irqchip_state)
+		return data->chip->irq_set_irqchip_state(data, which, val);
+
+	return 0;
+}
+EXPORT_SYMBOL(irq_chip_set_parent_state);
+
+/**
+ *	irq_chip_get_parent_state - get the state of a parent interrupt.
+ *	@data: Pointer to interrupt specific data
+ *	@which: one of IRQCHIP_STATE_* the caller wants to know
+ *	@state: a pointer to a boolean where the state is to be stored
+ *
+ */
+int irq_chip_get_parent_state(struct irq_data *data,
+			      enum irqchip_irq_state which,
+			      bool *state)
+{
+	data = data->parent_data;
+	if (!data)
+		return 0;
+
+	if (data->chip->irq_get_irqchip_state)
+		return data->chip->irq_get_irqchip_state(data, which, state);
+
+	return 0;
+}
+EXPORT_SYMBOL(irq_chip_get_parent_state);
+
 /**
  * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
  * NULL)