When an OMAP GPIO is used as an IRQ line, a call to gpio_request()
has to be made to initialize the OMAP GPIO bank before a driver
request the IRQ. Otherwise the call to request_irq() fails.
Drives should not be aware of this neither care wether an IRQ line
is a GPIO or not. They should just request the IRQ and this has to
be handled by the irq_chip driver.
With the current OMAP GPIO DT binding, if we define:
gpio6: gpio@49058000 {
compatible = "ti,omap3-gpio";
reg = <0x49058000 0x200>;
interrupts = <34>;
ti,hwmods = "gpio6";
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
};
interrupt-parent = <&gpio6>;
interrupts = <16 8>;
The GPIO is correctly mapped as an IRQ but a call to gpio_request()
is never made. Since a call to the custom IRQ domain .map function
handler is made for each GPIO used as an IRQ, the GPIO can be setup
and configured as input there automatically.
Signed-off-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx>
Tested-by: Enric Balletbo i Serra <eballetbo@xxxxxxxxx>
Acked-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@xxxxxxxxxxxx>
---
Changes since v3:
- Use bank->chip.of_node instead of_have_populated_dt() to check
DT or legacy boot as suggested by Jean-Christophe PLAGNIOL-VILLARD
- Add a comment that this is just a temporary solution until and
that it has to be removed once is handled by the IRQ core.
Changes since v2:
- Only make the call to gpio_request_one() conditional in the DT
case as suggested by Grant Likely.
Changes since v1:
- Split the irq domain mapping function handler and the GPIO
request in two different patches.
drivers/gpio/gpio-omap.c | 18 ++++++++++++++++++
1 files changed, 18 insertions(+), 0 deletions(-)
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index e260590..c4f0aa2 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -1090,6 +1090,8 @@ static int omap_gpio_irq_map(struct irq_domain *d, unsigned int virq,
irq_hw_number_t hwirq)
{
struct gpio_bank *bank = d->host_data;
+ int gpio;
+ int ret;
if (!bank)
return -EINVAL;
@@ -1104,6 +1106,22 @@ static int omap_gpio_irq_map(struct irq_domain *d, unsigned int virq,
set_irq_flags(virq, IRQF_VALID);
}
+ /*
+ * REVISIT most GPIO IRQ chip drivers need to call
+ * gpio_request() before a GPIO line can be used as an
+ * IRQ. Ideally this should be handled by the IRQ core
+ * but until then this has to be done on a per driver
+ * basis. Remove this once this is managed by the core.
+ */
+ if (bank->chip.of_node) {
+ gpio = irq_to_gpio(bank, hwirq);
+ ret = gpio_request_one(gpio, GPIOF_IN, NULL);
+ if (ret) {
+ dev_err(bank->dev, "Could not request GPIO%d\n", gpio);
+ return ret;
+ }
+ }
+
return 0;
}
--
1.7.7.6
--
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