From: Thierry Reding <[email protected]> Currently GPIO drivers are required to add the GPIO chip and its corresponding IRQ chip separately, which can result in a lot of boilerplate. Use the newly introduced struct gpio_irq_chip, embedded in struct gpio_chip, that drivers can fill in if they want the GPIO core to automatically register the IRQ chip associated with a GPIO chip.
Signed-off-by: Thierry Reding <[email protected]> --- drivers/gpio/gpiolib.c | 124 +++++++++++++++++++++++++++++++++++++++++++- include/linux/gpio/driver.h | 7 +++ 2 files changed, 129 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 685a05caf1ba..5bc99d08d538 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -72,6 +72,7 @@ static LIST_HEAD(gpio_lookup_list); LIST_HEAD(gpio_devices); static void gpiochip_free_hogs(struct gpio_chip *chip); +static int gpiochip_add_irqchip(struct gpio_chip *gpiochip); static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip); static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip); @@ -1266,6 +1267,10 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) if (status) goto err_remove_from_list; + status = gpiochip_add_irqchip(chip); + if (status) + goto err_remove_chip; + status = of_gpiochip_add(chip); if (status) goto err_remove_chip; @@ -1707,9 +1712,119 @@ static void gpiochip_irq_relres(struct irq_data *d) static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) { + unsigned int irq; + int err; + if (!gpiochip_irqchip_irq_valid(chip, offset)) return -ENXIO; - return irq_create_mapping(chip->irq.domain, offset); + + irq = irq_create_mapping(chip->irq.domain, offset); + if (!irq) + return 0; + + if (chip->irq.map) { + err = irq_set_parent(irq, chip->irq.map[offset]); + if (err < 0) + return err; + } + + return irq; +} + +/** + * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip + * @gpiochip: the GPIO chip to add the IRQ chip to + */ +static int gpiochip_add_irqchip(struct gpio_chip *gpiochip) +{ + struct irq_chip *irqchip = gpiochip->irq.chip; + const struct irq_domain_ops *ops; + struct device_node *np; + unsigned int type; + unsigned int i; + + if (!irqchip) + return 0; + + if (gpiochip->irq.parent_handler && gpiochip->can_sleep) { + chip_err(gpiochip, "you cannot have chained interrupts on a " + "chip that may sleep\n"); + return -EINVAL; + } + + type = gpiochip->irq.default_type; + np = gpiochip->parent->of_node; + +#ifdef CONFIG_OF_GPIO + /* + * If the gpiochip has an assigned OF node this takes precedence + * FIXME: get rid of this and use gpiochip->parent->of_node + * everywhere + */ + if (gpiochip->of_node) + np = gpiochip->of_node; +#endif + + /* + * Specifying a default trigger is a terrible idea if DT or ACPI is + * used to configure the interrupts, as you may end up with + * conflicting triggers. Tell the user, and reset to NONE. + */ + if (WARN(np && type != IRQ_TYPE_NONE, + "%s: Ignoring %u default trigger\n", np->full_name, type)) + type = IRQ_TYPE_NONE; + + if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { + acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), + "Ignoring %u default trigger\n", type); + type = IRQ_TYPE_NONE; + } + + gpiochip->to_irq = gpiochip_to_irq; + gpiochip->irq.default_type = type; + + if (gpiochip->irq.domain_ops) + ops = gpiochip->irq.domain_ops; + else + ops = &gpiochip_domain_ops; + + gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio, + 0, ops, gpiochip); + if (!gpiochip->irq.domain) + return -EINVAL; + + /* + * It is possible for a driver to override this, but only if the + * alternative functions are both implemented. + */ + if (!irqchip->irq_request_resources && + !irqchip->irq_release_resources) { + irqchip->irq_request_resources = gpiochip_irq_reqres; + irqchip->irq_release_resources = gpiochip_irq_relres; + } + + if (gpiochip->irq.parent_handler) { + void *data = gpiochip->irq.parent_handler_data ?: gpiochip; + + for (i = 0; i < gpiochip->irq.num_parents; i++) { + /* + * The parent IRQ chip is already using the chip_data + * for this IRQ chip, so our callbacks simply use the + * handler_data. + */ + irq_set_chained_handler_and_data(gpiochip->irq.parents[i], + gpiochip->irq.parent_handler, + data); + } + + gpiochip->irq.nested = false; + } else { + gpiochip->irq.nested = true; + } + + acpi_gpiochip_request_interrupts(gpiochip); + + return 0; } /** @@ -1724,7 +1839,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) acpi_gpiochip_free_interrupts(gpiochip); - if (gpiochip->irq.num_parents > 0) { + if (gpiochip->irq.chip) { struct gpio_irq_chip *irq = &gpiochip->irq; unsigned int i; @@ -1857,6 +1972,11 @@ EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key); #else /* CONFIG_GPIOLIB_IRQCHIP */ +static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip) +{ + return 0; +} + static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) { diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index c363ee198ff9..51fc7b023364 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -100,6 +100,13 @@ struct gpio_irq_chip { */ unsigned int *parents; + /** + * @map: + * + * A list of interrupt parents for each line of a GPIO chip. + */ + unsigned int *map; + /** * @nested: * -- 2.14.1
