gpio/omap: don't create an IRQ mapping for every GPIO on DT

When a GPIO is defined as an interrupt line using Device
Tree, a call to irq_create_of_mapping() is made that calls
irq_create_mapping(). So, is not necessary to do the mapping
for all OMAP GPIO lines and explicitly call irq_create_mapping()
on the driver probe() when booting with Device Tree.

Add a custom IRQ domain .map function handler that will be
called by irq_create_mapping() to map the GPIO lines used as IRQ.
This also allows to execute needed setup code such as configuring
a GPIO as input and enabling the GPIO bank.

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

Changes since v2:
  - Unconditionally do the IRQ setup in the .map() function and
    only call irq_create_mapping() in the gpio chip init to avoid
    code duplication as suggested by Grant Likely.

Changes since v1:
  - Split the addition of the .map function handler and the
    automatic gpio request in two different patches.
  - Add GPIO IRQ setup logic to the irq domain mapping function.
  - Only call irq_create_mapping for every GPIO on legacy boot.
  - Only setup a GPIO IRQ on the .map function for DeviceTree boot.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Enric Balletbo i Serra <eballetbo@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index dfeb3a3..5e667ff 100644 (file)
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -1068,24 +1068,50 @@ static void omap_gpio_chip_init(struct gpio_bank *bank)
 
        gpiochip_add(&bank->chip);
 
-       for (j = 0; j < bank->width; j++) {
-               int irq = irq_create_mapping(bank->domain, j);
-               irq_set_lockdep_class(irq, &gpio_lock_class);
-               irq_set_chip_data(irq, bank);
-               if (bank->is_mpuio) {
-                       omap_mpuio_alloc_gc(bank, irq, bank->width);
-               } else {
-                       irq_set_chip_and_handler(irq, &gpio_irq_chip,
-                                                handle_simple_irq);
-                       set_irq_flags(irq, IRQF_VALID);
-               }
-       }
+       /*
+        * REVISIT these explicit calls to irq_create_mapping()
+        * to do the GPIO to IRQ domain mapping for each GPIO in
+        * the bank can be removed once all OMAP platforms have
+        * been migrated to Device Tree boot only.
+        * Since in DT boot irq_create_mapping() is called from
+        * irq_create_of_mapping() only for the GPIO lines that
+        * are used as interrupts.
+        */
+       if (!bank->chip.of_node)
+               for (j = 0; j < bank->width; j++)
+                       irq_create_mapping(bank->domain, j);
        irq_set_chained_handler(bank->irq, gpio_irq_handler);
        irq_set_handler_data(bank->irq, bank);
 }
 
 static const struct of_device_id omap_gpio_match[];
 
+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;
+
+       if (!bank)
+               return -EINVAL;
+
+       irq_set_lockdep_class(virq, &gpio_lock_class);
+       irq_set_chip_data(virq, bank);
+       if (bank->is_mpuio) {
+               omap_mpuio_alloc_gc(bank, virq, bank->width);
+       } else {
+               irq_set_chip_and_handler(virq, &gpio_irq_chip,
+                                        handle_simple_irq);
+               set_irq_flags(virq, IRQF_VALID);
+       }
+
+       return 0;
+}
+
+static struct irq_domain_ops omap_gpio_irq_ops = {
+       .xlate  = irq_domain_xlate_onetwocell,
+       .map    = omap_gpio_irq_map,
+};
+
 static int omap_gpio_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
@@ -1151,10 +1177,10 @@ static int omap_gpio_probe(struct platform_device *pdev)
        }
 
        bank->domain = irq_domain_add_legacy(node, bank->width, irq_base,
-                                            0, &irq_domain_simple_ops, NULL);
+                                            0, &omap_gpio_irq_ops, bank);
 #else
        bank->domain = irq_domain_add_linear(node, bank->width,
-                                            &irq_domain_simple_ops, NULL);
+                                            &omap_gpio_irq_ops, bank);
 #endif
        if (!bank->domain) {
                dev_err(dev, "Couldn't register an IRQ domain\n");