Input: Generic GPIO Input device.

Supports keyboard matrixces, direct inputs, direct outputs and axes connected to gpios.

Change-Id: I5e921e6e3a1cc169316ee3b665f4cc21b5735114
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: Nick Pelly <npelly@google.com>

1 files changed, 84 insertions, 0 deletions

diff --git a/drivers/input/misc/gpio_output.c b/drivers/input/misc/gpio_output.c
new file mode 100644
index 000000000000..6f8453c97bd2
--- /dev/null
+++ b/drivers/input/misc/gpio_output.c
@@ -0,0 +1,84 @@
+/* drivers/input/misc/gpio_output.c
+ *
+ * Copyright (C) 2007 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/gpio.h>
+#include <linux/gpio_event.h>
+
+int gpio_event_output_event(
+	struct input_dev *input_dev, struct gpio_event_info *info, void **data,
+	unsigned int type, unsigned int code, int value)
+{
+	int i;
+	struct gpio_event_output_info *oi;
+	oi = container_of(info, struct gpio_event_output_info, info);
+	if (type != oi->type)
+		return 0;
+	if (!(oi->flags & GPIOEDF_ACTIVE_HIGH))
+		value = !value;
+	for (i = 0; i < oi->keymap_size; i++)
+		if (code == oi->keymap[i].code)
+			gpio_set_value(oi->keymap[i].gpio, value);
+	return 0;
+}
+
+int gpio_event_output_func(
+	struct input_dev *input_dev, struct gpio_event_info *info, void **data,
+	int func)
+{
+	int ret;
+	int i;
+	struct gpio_event_output_info *oi;
+	oi = container_of(info, struct gpio_event_output_info, info);
+
+	if (func == GPIO_EVENT_FUNC_SUSPEND || func == GPIO_EVENT_FUNC_RESUME)
+		return 0;
+
+	if (func == GPIO_EVENT_FUNC_INIT) {
+		int output_level = !(oi->flags & GPIOEDF_ACTIVE_HIGH);
+		for (i = 0; i < oi->keymap_size; i++)
+			input_set_capability(input_dev, oi->type,
+					     oi->keymap[i].code);
+
+		for (i = 0; i < oi->keymap_size; i++) {
+			ret = gpio_request(oi->keymap[i].gpio,
+					   "gpio_event_output");
+			if (ret) {
+				pr_err("gpio_event_output_func: gpio_request "
+					"failed for %d\n", oi->keymap[i].gpio);
+				goto err_gpio_request_failed;
+			}
+			ret = gpio_direction_output(oi->keymap[i].gpio,
+						    output_level);
+			if (ret) {
+				pr_err("gpio_event_output_func: "
+					"gpio_direction_output failed for %d\n",
+					oi->keymap[i].gpio);
+				goto err_gpio_direction_output_failed;
+			}
+		}
+		return 0;
+	}
+
+	ret = 0;
+	for (i = oi->keymap_size - 1; i >= 0; i--) {
+err_gpio_direction_output_failed:
+		gpio_free(oi->keymap[i].gpio);
+err_gpio_request_failed:
+		;
+	}
+	return ret;
+}
+