leds: leds-ns2: add device tree binding

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

2 files changed, 101 insertions, 3 deletions

diff --git a/Documentation/devicetree/bindings/gpio/leds-ns2.txt b/Documentation/devicetree/bindings/gpio/leds-ns2.txt
new file mode 100644
index 000000000000..aef3aca34d2d
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/leds-ns2.txt
@@ -0,0 +1,26 @@
+Binding for dual-GPIO LED found on Network Space v2 (and parents).
+
+Required properties:
+- compatible: "lacie,ns2-leds".
+
+Each LED is represented as a sub-node of the ns2-leds device.
+
+Required sub-node properties:
+- cmd-gpio: Command LED GPIO. See OF device-tree GPIO specification.
+- slow-gpio: Slow LED GPIO. See OF device-tree GPIO specification.
+
+Optional sub-node properties:
+- label: Name for this LED. If omitted, the label is taken from the node name.
+- linux,default-trigger: Trigger assigned to the LED.
+
+Example:
+
+ns2-leds {
+        compatible = "lacie,ns2-leds";
+
+        blue-sata {
+                label = "ns2:blue:sata";
+                slow-gpio = <&gpio0 29 0>;
+                cmd-gpio = <&gpio0 30 0>;
+        };
+};
diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
index d176ec83f5d9..d64cc2227fd9 100644
--- a/drivers/leds/leds-ns2.c
+++ b/drivers/leds/leds-ns2.c
@@ -30,6 +30,7 @@
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/platform_data/leds-kirkwood-ns2.h>
+#include <linux/of_gpio.h>
 
 /*
  * The Network Space v2 dual-GPIO LED is wired to a CPLD and can blink in
@@ -263,6 +264,62 @@ static void delete_ns2_led(struct ns2_led_data *led_dat)
         gpio_free(led_dat->slow);
 }
 
+#ifdef CONFIG_OF_GPIO
+/*
+ * Translate OpenFirmware node properties into platform_data.
+ */
+static int __devinit
+ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
+{
+        struct device_node *np = dev->of_node;
+        struct device_node *child;
+        struct ns2_led *leds;
+        int num_leds = 0;
+        int i = 0;
+
+        num_leds = of_get_child_count(np);
+        if (!num_leds)
+                return -ENODEV;
+
+        leds = devm_kzalloc(dev, num_leds * sizeof(struct ns2_led),
+                            GFP_KERNEL);
+        if (!leds)
+                return -ENOMEM;
+
+        for_each_child_of_node(np, child) {
+                const char *string;
+                int ret;
+
+                ret = of_get_named_gpio(child, "cmd-gpio", 0);
+                if (ret < 0)
+                        return ret;
+                leds[i].cmd = ret;
+                ret = of_get_named_gpio(child, "slow-gpio", 0);
+                if (ret < 0)
+                        return ret;
+                leds[i].slow = ret;
+                ret = of_property_read_string(child, "label", &string);
+                leds[i].name = (ret == 0) ? string : child->name;
+                ret = of_property_read_string(child, "linux,default-trigger",
+                                              &string);
+                if (ret == 0)
+                        leds[i].default_trigger = string;
+
+                i++;
+        }
+
+        pdata->leds = leds;
+        pdata->num_leds = num_leds;
+
+        return 0;
+}
+
+static const struct of_device_id of_ns2_leds_match[] = {
+        { .compatible = "lacie,ns2-leds", },
+        {},
+};
+#endif /* CONFIG_OF_GPIO */
+
 static int __devinit ns2_led_probe(struct platform_device *pdev)
 {
         struct ns2_led_platform_data *pdata = pdev->dev.platform_data;
@@ -270,11 +327,25 @@ static int __devinit ns2_led_probe(struct platform_device *pdev)
         int i;
         int ret;
 
+#ifdef CONFIG_OF_GPIO
+        if (!pdata) {
+                pdata = devm_kzalloc(&pdev->dev,
+                                     sizeof(struct ns2_led_platform_data),
+                                     GFP_KERNEL);
+                if (!pdata)
+                        return -ENOMEM;
+
+                ret = ns2_leds_get_of_pdata(&pdev->dev, pdata);
+                if (ret)
+                        return ret;
+        }
+#else
         if (!pdata)
                 return -EINVAL;
+#endif /* CONFIG_OF_GPIO */
 
         leds_data = devm_kzalloc(&pdev->dev, sizeof(struct ns2_led_data) *
-                            pdata->num_leds, GFP_KERNEL);
+                                 pdata->num_leds, GFP_KERNEL);
         if (!leds_data)
                 return -ENOMEM;
 
@@ -312,8 +383,9 @@ static struct platform_driver ns2_led_driver = {
         .probe          = ns2_led_probe,
         .remove         = __devexit_p(ns2_led_remove),
         .driver         = {
-                .name   = "leds-ns2",
-                .owner  = THIS_MODULE,
+                .name           = "leds-ns2",
+                .owner          = THIS_MODULE,
+                .of_match_table = of_match_ptr(of_ns2_leds_match),
         },
 };