init android origin source code

1 files changed, 292 insertions, 0 deletions

diff --git a/ANDROID_3.4.5/drivers/input/misc/rotary_encoder.c b/ANDROID_3.4.5/drivers/input/misc/rotary_encoder.c
new file mode 100644
index 00000000..f07f7841
--- /dev/null
+++ b/ANDROID_3.4.5/drivers/input/misc/rotary_encoder.c
@@ -0,0 +1,292 @@
+/*
+ * rotary_encoder.c
+ *
+ * (c) 2009 Daniel Mack <daniel@caiaq.de>
+ * Copyright (C) 2011 Johan Hovold <jhovold@gmail.com>
+ *
+ * state machine code inspired by code from Tim Ruetz
+ *
+ * A generic driver for rotary encoders connected to GPIO lines.
+ * See file:Documentation/input/rotary-encoder.txt for more information
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/rotary_encoder.h>
+#include <linux/slab.h>
+
+#define DRV_NAME "rotary-encoder"
+
+struct rotary_encoder {
+	struct input_dev *input;
+	struct rotary_encoder_platform_data *pdata;
+
+	unsigned int axis;
+	unsigned int pos;
+
+	unsigned int irq_a;
+	unsigned int irq_b;
+
+	bool armed;
+	unsigned char dir;	/* 0 - clockwise, 1 - CCW */
+
+	char last_stable;
+};
+
+static int rotary_encoder_get_state(struct rotary_encoder_platform_data *pdata)
+{
+	int a = !!gpio_get_value(pdata->gpio_a);
+	int b = !!gpio_get_value(pdata->gpio_b);
+
+	a ^= pdata->inverted_a;
+	b ^= pdata->inverted_b;
+
+	return ((a << 1) | b);
+}
+
+static void rotary_encoder_report_event(struct rotary_encoder *encoder)
+{
+	struct rotary_encoder_platform_data *pdata = encoder->pdata;
+
+	if (pdata->relative_axis) {
+		input_report_rel(encoder->input,
+				 pdata->axis, encoder->dir ? -1 : 1);
+	} else {
+		unsigned int pos = encoder->pos;
+
+		if (encoder->dir) {
+			/* turning counter-clockwise */
+			if (pdata->rollover)
+				pos += pdata->steps;
+			if (pos)
+				pos--;
+		} else {
+			/* turning clockwise */
+			if (pdata->rollover || pos < pdata->steps)
+				pos++;
+		}
+
+		if (pdata->rollover)
+			pos %= pdata->steps;
+
+		encoder->pos = pos;
+		input_report_abs(encoder->input, pdata->axis, encoder->pos);
+	}
+
+	input_sync(encoder->input);
+}
+
+static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)
+{
+	struct rotary_encoder *encoder = dev_id;
+	int state;
+
+	state = rotary_encoder_get_state(encoder->pdata);
+
+	switch (state) {
+	case 0x0:
+		if (encoder->armed) {
+			rotary_encoder_report_event(encoder);
+			encoder->armed = false;
+		}
+		break;
+
+	case 0x1:
+	case 0x2:
+		if (encoder->armed)
+			encoder->dir = state - 1;
+		break;
+
+	case 0x3:
+		encoder->armed = true;
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)
+{
+	struct rotary_encoder *encoder = dev_id;
+	int state;
+
+	state = rotary_encoder_get_state(encoder->pdata);
+
+	switch (state) {
+	case 0x00:
+	case 0x03:
+		if (state != encoder->last_stable) {
+			rotary_encoder_report_event(encoder);
+			encoder->last_stable = state;
+		}
+		break;
+
+	case 0x01:
+	case 0x02:
+		encoder->dir = (encoder->last_stable + state) & 0x01;
+		break;
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int __devinit rotary_encoder_probe(struct platform_device *pdev)
+{
+	struct rotary_encoder_platform_data *pdata = pdev->dev.platform_data;
+	struct rotary_encoder *encoder;
+	struct input_dev *input;
+	irq_handler_t handler;
+	int err;
+
+	if (!pdata) {
+		dev_err(&pdev->dev, "missing platform data\n");
+		return -ENOENT;
+	}
+
+	encoder = kzalloc(sizeof(struct rotary_encoder), GFP_KERNEL);
+	input = input_allocate_device();
+	if (!encoder || !input) {
+		dev_err(&pdev->dev, "failed to allocate memory for device\n");
+		err = -ENOMEM;
+		goto exit_free_mem;
+	}
+
+	encoder->input = input;
+	encoder->pdata = pdata;
+	encoder->irq_a = gpio_to_irq(pdata->gpio_a);
+	encoder->irq_b = gpio_to_irq(pdata->gpio_b);
+
+	/* create and register the input driver */
+	input->name = pdev->name;
+	input->id.bustype = BUS_HOST;
+	input->dev.parent = &pdev->dev;
+
+	if (pdata->relative_axis) {
+		input->evbit[0] = BIT_MASK(EV_REL);
+		input->relbit[0] = BIT_MASK(pdata->axis);
+	} else {
+		input->evbit[0] = BIT_MASK(EV_ABS);
+		input_set_abs_params(encoder->input,
+				     pdata->axis, 0, pdata->steps, 0, 1);
+	}
+
+	err = input_register_device(input);
+	if (err) {
+		dev_err(&pdev->dev, "failed to register input device\n");
+		goto exit_free_mem;
+	}
+
+	/* request the GPIOs */
+	err = gpio_request(pdata->gpio_a, DRV_NAME);
+	if (err) {
+		dev_err(&pdev->dev, "unable to request GPIO %d\n",
+			pdata->gpio_a);
+		goto exit_unregister_input;
+	}
+
+	err = gpio_direction_input(pdata->gpio_a);
+	if (err) {
+		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
+			pdata->gpio_a);
+		goto exit_unregister_input;
+	}
+
+	err = gpio_request(pdata->gpio_b, DRV_NAME);
+	if (err) {
+		dev_err(&pdev->dev, "unable to request GPIO %d\n",
+			pdata->gpio_b);
+		goto exit_free_gpio_a;
+	}
+
+	err = gpio_direction_input(pdata->gpio_b);
+	if (err) {
+		dev_err(&pdev->dev, "unable to set GPIO %d for input\n",
+			pdata->gpio_b);
+		goto exit_free_gpio_a;
+	}
+
+	/* request the IRQs */
+	if (pdata->half_period) {
+		handler = &rotary_encoder_half_period_irq;
+		encoder->last_stable = rotary_encoder_get_state(pdata);
+	} else {
+		handler = &rotary_encoder_irq;
+	}
+
+	err = request_irq(encoder->irq_a, handler,
+			  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+			  DRV_NAME, encoder);
+	if (err) {
+		dev_err(&pdev->dev, "unable to request IRQ %d\n",
+			encoder->irq_a);
+		goto exit_free_gpio_b;
+	}
+
+	err = request_irq(encoder->irq_b, handler,
+			  IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+			  DRV_NAME, encoder);
+	if (err) {
+		dev_err(&pdev->dev, "unable to request IRQ %d\n",
+			encoder->irq_b);
+		goto exit_free_irq_a;
+	}
+
+	platform_set_drvdata(pdev, encoder);
+
+	return 0;
+
+exit_free_irq_a:
+	free_irq(encoder->irq_a, encoder);
+exit_free_gpio_b:
+	gpio_free(pdata->gpio_b);
+exit_free_gpio_a:
+	gpio_free(pdata->gpio_a);
+exit_unregister_input:
+	input_unregister_device(input);
+	input = NULL; /* so we don't try to free it */
+exit_free_mem:
+	input_free_device(input);
+	kfree(encoder);
+	return err;
+}
+
+static int __devexit rotary_encoder_remove(struct platform_device *pdev)
+{
+	struct rotary_encoder *encoder = platform_get_drvdata(pdev);
+	struct rotary_encoder_platform_data *pdata = pdev->dev.platform_data;
+
+	free_irq(encoder->irq_a, encoder);
+	free_irq(encoder->irq_b, encoder);
+	gpio_free(pdata->gpio_a);
+	gpio_free(pdata->gpio_b);
+	input_unregister_device(encoder->input);
+	platform_set_drvdata(pdev, NULL);
+	kfree(encoder);
+
+	return 0;
+}
+
+static struct platform_driver rotary_encoder_driver = {
+	.probe		= rotary_encoder_probe,
+	.remove		= __devexit_p(rotary_encoder_remove),
+	.driver		= {
+		.name	= DRV_NAME,
+		.owner	= THIS_MODULE,
+	}
+};
+module_platform_driver(rotary_encoder_driver);
+
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_DESCRIPTION("GPIO rotary encoder driver");
+MODULE_AUTHOR("Daniel Mack <daniel@caiaq.de>, Johan Hovold");
+MODULE_LICENSE("GPL v2");