Re: [PATCH 2/3] Input: gpio_keys.c: Added support for device-tree platform data

Signed-off-by: David Jander <redacted>
---
 .../devicetree/bindings/gpio/gpio_keys.txt         |   49 ++++++++
 drivers/input/keyboard/gpio_keys.c                 |  131 ++++++++++++++++++++
 2 files changed, 180 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio_keys.txt

diff --git a/Documentation/devicetree/bindings/gpio/gpio_keys.txt b/Documentation/devicetree/bindings/gpio/gpio_keys.txt
new file mode 100644
index 0000000..ff8ba2e
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio_keys.txt

@@ -0,0 +1,49 @@
+Device-Tree bindings for input/gpio_keys.c keyboard driver
+
+Required properties:
+       - compatible = "linux,gpio-keys", "gpio-keys";

+
+Example nodes:
+
+       gpio_keys {
+                       compatible = "linux,gpio-keys", "gpio-keys";
+                       #address-cells = <1>;
+                       #size-cells = <0>;
+                       linux,autorepeat;
+                       button@20 {
+                               label = "GPIO Key ESC";
+                               linux,code = <1>;
+                               reg = <0x20>;
+                               linux,active_low;
+                               linux,input_type = <1>;
+                       };
+                       button@21 {
+                               label = "GPIO Key UP";
+                               linux,code = <103>;
+                               reg = <0x21>;
+                               linux,active_low;
+                               linux,input_type = <1>;
+                       };
+                       ...
+

diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index 987498e..4efd067 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c

@@ -3,6 +3,9 @@

 *
 * Copyright 2005 Phil Blundell
 *
+ * Added OF support:
+ * Copyright 2010 David Jander [off-list ref]
+ *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.

@@ -25,6 +28,8 @@

 #include <linux/gpio_keys.h>
 #include <linux/workqueue.h>
 #include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>

 struct gpio_button_data {
       struct gpio_keys_button *button;

@@ -42,6 +47,7 @@ struct gpio_keys_drvdata {

       int (*enable)(struct device *dev);
       void (*disable)(struct device *dev);
       struct gpio_button_data data[0];
+       struct gpio_keys_platform_data *dyn_pdata;
 };

 /*

@@ -442,18 +448,131 @@ static void gpio_keys_close(struct input_dev *input)

               ddata->disable(input->dev.parent);
 }

+/*
+ * Handlers for alternative sources of platform_data
+ */
+#ifdef CONFIG_OF
+/*
+ * Translate OpenFirmware node properties into platform_data
+ */
+static struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+       struct gpio_keys_platform_data *pdata;
+       struct device_node *node, *pp;
+       int i;
+       struct gpio_keys_button *buttons;
+       const u32 *reg;
+       int len;
+
+       node = dev->of_node;
+       if (node == NULL)
+               return NULL;
+
+       pdata = kzalloc(sizeof(struct gpio_keys_platform_data), GFP_KERNEL);
+       if (pdata == NULL) {
+               dev_err(dev, "Unable to allocate platform_data\n");
+               return NULL;
+       }
+
+       pdata->rep = !!of_get_property(node, "linux,autorepeat", &len);
+
+       /* First count the subnodes */
+       pdata->nbuttons = 0;
+       pp = NULL;
+       while ((pp = of_get_next_child(node, pp)))
+               pdata->nbuttons++;
+
+       if (pdata->nbuttons == 0)
+               return NULL;
+
+       buttons = kzalloc(pdata->nbuttons * sizeof(*buttons), GFP_KERNEL);
+       if (!buttons)
+               return NULL;
+
+       pp = NULL;
+       i = 0;
+       while ((pp = of_get_next_child(node, pp))) {
+               const char *lbl;
+
+               reg = of_get_property(pp, "reg", &len);
+               if (!reg) {
+                       pdata->nbuttons--;
+                       printk("Found button without reg\n");
+                       continue;
+               }
+               buttons[i].gpio = reg[0];
+
+               reg = of_get_property(pp, "linux,code", &len);
+               if (!reg) {
+                       dev_err(dev, "Button without keycode: 0x%x\n", buttons[i].gpio);
+                       return NULL;
+               }
+               buttons[i].code = reg[0];
+
+               lbl = of_get_property(pp, "label", &len);
+               buttons[i].desc = (char *)lbl;
+
+               buttons[i].active_low = !!of_get_property(pp, "linux,active_low", NULL);
+
+               reg = of_get_property(pp, "linux,input_type", &len);
+               if (reg)
+                       buttons[i].type = reg[0];

+               else
+                       buttons[i].type = EV_KEY;
+
+               buttons[i].wakeup = !!of_get_property(pp, "linux,wakeup", NULL);
+
+               reg = of_get_property(pp, "linux,debounc_interval", &len);
+               if (reg)
+                       buttons[i].debounce_interval = reg[0];
+               else
+                       buttons[i].debounce_interval = 5;
+
+               buttons[i].can_disable = (bool)!!of_get_property(pp, "linux,can_disable", NULL);
+               i++;
+       }
+
+       pdata->buttons = buttons;
+
+       return pdata;
+}
+#else
+static struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+       return NULL;
+}
+#endif
+
 static int __devinit gpio_keys_probe(struct platform_device *pdev)
 {
       struct gpio_keys_drvdata *ddata;
       struct device *dev = &pdev->dev;
       struct gpio_keys_platform_data *pdata = dev->platform_data;
+       struct gpio_keys_platform_data *dyn_pdata = NULL;
       struct input_dev *input;
       int i, error;
       int wakeup = 0;

+       if (!pdata) {
+               pdata = gpio_keys_get_devtree_pdata(dev);
+               if (!pdata)
+                       return -ENODEV;
+               /*
+                * Unlike normal platform_data, this is allocated
+                * dynamically and must be freed in the driver
+                */
+               dev->platform_data = pdata;
+               dyn_pdata = pdata;
+       }
+
       ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
                       pdata->nbuttons * sizeof(struct gpio_button_data),
                       GFP_KERNEL);
+
+       ddata->dyn_pdata = dyn_pdata;
+
       input = input_allocate_device();
       if (!ddata || !input) {
               dev_err(dev, "failed to allocate state\n");

@@ -565,12 +684,21 @@ static int __devexit gpio_keys_remove(struct platform_device *pdev)

               cancel_work_sync(&ddata->data[i].work);
               gpio_free(pdata->buttons[i].gpio);
       }
+       if (ddata->dyn_pdata) {
+               kfree(pdata->buttons);
+               kfree(pdata);
+       }

       input_unregister_device(input);

       return 0;
 }

+static struct of_device_id gpio_keys_of_match[] = {
+       { .compatible = "linux,gpio-keys", },
+       { .compatible = "gpio-keys", },

+       {},
+};

 #ifdef CONFIG_PM
 static int gpio_keys_suspend(struct device *dev)

@@ -618,6 +746,8 @@ static const struct dev_pm_ops gpio_keys_pm_ops = {

 };
 #endif

+MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
+
 static struct platform_driver gpio_keys_device_driver = {
       .probe          = gpio_keys_probe,
       .remove         = __devexit_p(gpio_keys_remove),

@@ -627,6 +757,7 @@ static struct platform_driver gpio_keys_device_driver = {

 #ifdef CONFIG_PM
               .pm     = &gpio_keys_pm_ops,
 #endif
+               .of_match_table = gpio_keys_of_match,
       }
 };

--
1.7.4.1