gpio: ixp4xx: Add OF probing support

This adds device tree probe and registration support for
the IXP4xx GPIO driver.

Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-ixp4xx.c b/drivers/gpio/gpio-ixp4xx.c
index eaf317f73f75d97fd03b6c96cc24c938af0308d7..4b1cf7ea858d6030d17c8ceb98a98865242c41d9 100644 (file)
--- a/drivers/gpio/gpio-ixp4xx.c
+++ b/drivers/gpio/gpio-ixp4xx.c
@@ -11,6 +11,7 @@
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/irqchip.h>
+#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/bitops.h>
 /* Include that go away with DT transition */
@@ -306,6 +307,7 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev)
 {
        unsigned long flags;
        struct device *dev = &pdev->dev;
+       struct device_node *np = dev->of_node;
        struct irq_domain *parent;
        struct resource *res;
        struct ixp4xx_gpio *g;
@@ -382,11 +384,27 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev)
         * from IRQCHIP_DECLARE(), then use of_node_to_fwnode() to get
         * the fwnode. For now we need this boardfile style code.
         */
-       parent = ixp4xx_get_irq_domain();
-       g->fwnode = irq_domain_alloc_fwnode(g->base);
-       if (!g->fwnode) {
-               dev_err(dev, "no domain base\n");
-               return -ENODEV;
+       if (np) {
+               struct device_node *irq_parent;
+
+               irq_parent = of_irq_find_parent(np);
+               if (!irq_parent) {
+                       dev_err(dev, "no IRQ parent node\n");
+                       return -ENODEV;
+               }
+               parent = irq_find_host(irq_parent);
+               if (!parent) {
+                       dev_err(dev, "no IRQ parent domain\n");
+                       return -ENODEV;
+               }
+               g->fwnode = of_node_to_fwnode(np);
+       } else {
+               parent = ixp4xx_get_irq_domain();
+               g->fwnode = irq_domain_alloc_fwnode(g->base);
+               if (!g->fwnode) {
+                       dev_err(dev, "no domain base\n");
+                       return -ENODEV;
+               }
        }
        g->domain = irq_domain_create_hierarchy(parent,
                                                IRQ_DOMAIN_FLAG_HIERARCHY,
@@ -404,28 +422,31 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev)
         * After adding OF support, this is no longer needed: irqs
         * will be allocated for the respective fwnodes.
         */
-       for (i = 0; i < ARRAY_SIZE(ixp4xx_gpiomap); i++) {
-               const struct ixp4xx_gpio_map *map = &ixp4xx_gpiomap[i];
-               struct irq_fwspec fwspec;
-
-               fwspec.fwnode = g->fwnode;
-               /* This is the hwirq for the GPIO line side of things */
-               fwspec.param[0] = map->gpio_offset;
-               fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
-               fwspec.param_count = 2;
-               ret = __irq_domain_alloc_irqs(g->domain,
-                                             -1, /* just pick something */
-                                             1,
-                                             NUMA_NO_NODE,
-                                             &fwspec,
-                                             false,
-                                             NULL);
-               if (ret < 0) {
-                       irq_domain_free_fwnode(g->fwnode);
-                       dev_err(dev,
-                               "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
-                               map->gpio_offset, map->parent_hwirq, ret);
-                       return ret;
+       if (!np) {
+               for (i = 0; i < ARRAY_SIZE(ixp4xx_gpiomap); i++) {
+                       const struct ixp4xx_gpio_map *map = &ixp4xx_gpiomap[i];
+                       struct irq_fwspec fwspec;
+
+                       fwspec.fwnode = g->fwnode;
+                       /* This is the hwirq for the GPIO line side of things */
+                       fwspec.param[0] = map->gpio_offset;
+                       fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
+                       fwspec.param_count = 2;
+                       ret = __irq_domain_alloc_irqs(g->domain,
+                                                     -1, /* just pick something */
+                                                     1,
+                                                     NUMA_NO_NODE,
+                                                     &fwspec,
+                                                     false,
+                                                     NULL);
+                       if (ret < 0) {
+                               irq_domain_free_fwnode(g->fwnode);
+                               dev_err(dev,
+                                       "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
+                                       map->gpio_offset, map->parent_hwirq,
+                                       ret);
+                               return ret;
+                       }
                }
        }
 
@@ -435,9 +456,18 @@ static int ixp4xx_gpio_probe(struct platform_device *pdev)
        return 0;
 }
 
+static const struct of_device_id ixp4xx_gpio_of_match[] = {
+       {
+               .compatible = "intel,ixp4xx-gpio",
+       },
+       {},
+};
+
+
 static struct platform_driver ixp4xx_gpio_driver = {
        .driver = {
                .name           = "ixp4xx-gpio",
+               .of_match_table = of_match_ptr(ixp4xx_gpio_of_match),
        },
        .probe = ixp4xx_gpio_probe,
 };