gpio: simplify adding threaded interrupts
This tries to simplify the use of CONFIG_GPIOLIB_IRQCHIP when
using threaded interrupts: add a new call
gpiochip_irqchip_add_nested() to indicate that we're dealing
with a nested rather than a chained irqchip, then create a
separate gpiochip_set_nested_irqchip() to mirror
the gpiochip_set_chained_irqchip() call to connect the
parent and child interrupts.
In the nested case gpiochip_set_nested_irqchip() does nothing
more than call irq_set_parent() on each valid child interrupt,
which has little semantic effect in the kernel, but this is
probably still formally correct.
Update all drivers using nested interrupts to use
gpiochip_irqchip_add_nested() so we can now see clearly
which these users are.
The DLN2 driver can drop its specific hack with
.irq_not_threaded as we now recognize whether a chip is
threaded or not from its use of gpiochip_irqchip_add_nested()
signature rather than from inspecting .can_sleep.
We rename the .irq_parent to .irq_chained_parent since this
parent IRQ is only really kept around for the chained
interrupt handlers.
Cc: Lars Poeschel <poeschel@lemonage.de>
Cc: Octavian Purdila <octavian.purdila@intel.com>
Cc: Daniel Baluta <daniel.baluta@intel.com>
Cc: Bin Gao <bin.gao@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>
Cc: Semen Protsenko <semen.protsenko@globallogic.com>
Cc: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Phil Reid <preid@electromag.com.au>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f0fc3a0..7be4fda 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1439,7 +1439,7 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
}
/**
- * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip
+ * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
* @gpiochip: the gpiochip to set the irqchip chain to
* @irqchip: the irqchip to chain to the gpiochip
* @parent_irq: the irq number corresponding to the parent IRQ for this
@@ -1448,10 +1448,10 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
* coming out of the gpiochip. If the interrupt is nested rather than
* cascaded, pass NULL in this handler argument
*/
-void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
- struct irq_chip *irqchip,
- int parent_irq,
- irq_flow_handler_t parent_handler)
+static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip,
+ struct irq_chip *irqchip,
+ int parent_irq,
+ irq_flow_handler_t parent_handler)
{
unsigned int offset;
@@ -1475,7 +1475,7 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
irq_set_chained_handler_and_data(parent_irq, parent_handler,
gpiochip);
- gpiochip->irq_parent = parent_irq;
+ gpiochip->irq_chained_parent = parent_irq;
}
/* Set the parent IRQ for all affected IRQs */
@@ -1486,9 +1486,48 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
parent_irq);
}
}
+
+/**
+ * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
+ * @gpiochip: the gpiochip to set the irqchip chain to
+ * @irqchip: the irqchip to chain to the gpiochip
+ * @parent_irq: the irq number corresponding to the parent IRQ for this
+ * chained irqchip
+ * @parent_handler: the parent interrupt handler for the accumulated IRQ
+ * coming out of the gpiochip. If the interrupt is nested rather than
+ * cascaded, pass NULL in this handler argument
+ */
+void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
+ struct irq_chip *irqchip,
+ int parent_irq,
+ irq_flow_handler_t parent_handler)
+{
+ gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
+ parent_handler);
+}
EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
/**
+ * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
+ * @gpiochip: the gpiochip to set the irqchip nested handler to
+ * @irqchip: the irqchip to nest to the gpiochip
+ * @parent_irq: the irq number corresponding to the parent IRQ for this
+ * nested irqchip
+ */
+void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
+ struct irq_chip *irqchip,
+ int parent_irq)
+{
+ if (!gpiochip->irq_nested) {
+ chip_err(gpiochip, "tried to nest a chained gpiochip\n");
+ return;
+ }
+ gpiochip_set_cascaded_irqchip(gpiochip, irqchip, parent_irq,
+ NULL);
+}
+EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);
+
+/**
* gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
* @d: the irqdomain used by this irqchip
* @irq: the global irq number used by this GPIO irqchip irq
@@ -1510,8 +1549,8 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
*/
irq_set_lockdep_class(irq, chip->lock_key);
irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler);
- /* Chips that can sleep need nested thread handlers */
- if (chip->can_sleep && !chip->irq_not_threaded)
+ /* Chips that use nested thread handlers have them marked */
+ if (chip->irq_nested)
irq_set_nested_thread(irq, 1);
irq_set_noprobe(irq);
@@ -1529,7 +1568,7 @@ static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
{
struct gpio_chip *chip = d->host_data;
- if (chip->can_sleep)
+ if (chip->irq_nested)
irq_set_nested_thread(irq, 0);
irq_set_chip_and_handler(irq, NULL, NULL);
irq_set_chip_data(irq, NULL);
@@ -1584,9 +1623,9 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
acpi_gpiochip_free_interrupts(gpiochip);
- if (gpiochip->irq_parent) {
- irq_set_chained_handler(gpiochip->irq_parent, NULL);
- irq_set_handler_data(gpiochip->irq_parent, NULL);
+ if (gpiochip->irq_chained_parent) {
+ irq_set_chained_handler(gpiochip->irq_chained_parent, NULL);
+ irq_set_handler_data(gpiochip->irq_chained_parent, NULL);
}
/* Remove all IRQ mappings and delete the domain */
@@ -1610,7 +1649,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
}
/**
- * gpiochip_irqchip_add() - adds an irqchip to a gpiochip
+ * _gpiochip_irqchip_add() - adds an irqchip to a gpiochip
* @gpiochip: the gpiochip to add the irqchip to
* @irqchip: the irqchip to add to the gpiochip
* @first_irq: if not dynamically assigned, the base (first) IRQ to
@@ -1618,6 +1657,8 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
* @handler: the irq handler to use (often a predefined irq core function)
* @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
* to have the core avoid setting up any default type in the hardware.
+ * @nested: whether this is a nested irqchip calling handle_nested_irq()
+ * in its IRQ handler
* @lock_key: lockdep class
*
* This function closely associates a certain irqchip with a certain
@@ -1639,6 +1680,7 @@ int _gpiochip_irqchip_add(struct gpio_chip *gpiochip,
unsigned int first_irq,
irq_flow_handler_t handler,
unsigned int type,
+ bool nested,
struct lock_class_key *lock_key)
{
struct device_node *of_node;
@@ -1653,6 +1695,7 @@ int _gpiochip_irqchip_add(struct gpio_chip *gpiochip,
pr_err("missing gpiochip .dev parent pointer\n");
return -EINVAL;
}
+ gpiochip->irq_nested = nested;
of_node = gpiochip->parent->of_node;
#ifdef CONFIG_OF_GPIO
/*