Hello,
I have an SPI device that sends an IRQ to the CPU (MPC5200) via GPIO (GPT6):
gpt6: ti...@660 { // General Purpose Timer GPT6 in GPIO mode for
SMC4000IO sample irq.
compatible = "fsl,mpc5200b-gpt-gpio","fsl,mpc5200-gpt-gpio";
cell-index = <6>;
reg = <0x660 0x10>;
interrupts = <1 15 0>;
interrupt-parent = <&mpc5200_pic>;
gpio-controller;
#gpio-cells = <2>;
};
s...@f00 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "fsl,mpc5200b-spi","fsl,mpc5200-spi";
reg = <0xf00 0x20>;
interrupts = <2 13 0 2 14 0>;
interrupt-parent = <&mpc5200_pic>;
gpios = <&gpt4 0 0>;
io-control...@0 {
compatible = "microkey,smc4000io";
linux,modalias = "of_smc4000io";
spi-max-frequency = <1000000>;
spi-cpha;
reg = <0>;
// gpios: first is IRQ to cpu
gpios = <&gpt6 0 0>;
word-delay-us = <0>;
};
};
I've got it working for a mm_gpio, but it's probably not the right
approach, I have the following questions to get to the right solution:
- Should gpiolib's gpio_to_irq function indeed return the IRQ that was
specified at the GPIO by the DTS (interrupts = <1 15 0>)?
The effect is that if the IRQ is not specified in the DTS the
gpio_to_irq returns NO_IRQ.
(On the MPC5200 the IRQ is fixed for GPT6, so instead the cell-index
could also be used to return a gpio's IRQ)
- If a GPIO controller supports several GPIOs but one IRQ, is it
defined what gpio_to_irq should return?
- Is it okay for gpio_to_irq to return NO_IRQ? (returned by
irq_of_parse_and_map) if irq is not defined?
Henk.
diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c
index 6eea601..81927d7 100644
--- a/drivers/of/gpio.c
+++ b/drivers/of/gpio.c
@@ -150,6 +150,17 @@ int of_gpio_simple_xlate(struct of_gpio_chip
*of_gc, struct device_node *np,
}
EXPORT_SYMBOL(of_gpio_simple_xlate);
+static int of_mm_gpio_to_irq(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc;
+ struct of_gpio_chip *of_gc;
+
+ of_gc = container_of(gc, struct of_gpio_chip, gc);
+ mm_gc = container_of(of_gc, struct of_mm_gpio_chip, of_gc);
+ return mm_gc->irq;
+
+}
+
/**
* of_mm_gpiochip_add - Add memory mapped GPIO chip (bank)
* @np: device node of the GPIO chip
@@ -188,6 +199,9 @@ int of_mm_gpiochip_add(struct device_node *np,
gc->base = -1;
+ mm_gc->irq = irq_of_parse_and_map(np, 0);
+ gc->to_irq = of_mm_gpio_to_irq;
+
if (!of_gc->xlate)
of_gc->xlate = of_gpio_simple_xlate;
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index fc2472c..17fe9ed 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -54,6 +54,7 @@ struct of_mm_gpio_chip {
struct of_gpio_chip of_gc;
void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
void __iomem *regs;
+ int irq;
};
static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-dev
