1 files changed, 453 insertions, 0 deletions
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
new file mode 100644
index 00000000000..e9b2e7cb05b
--- /dev/null
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -0,0 +1,453 @@
+/*
+ *  GPIO driven matrix keyboard driver
+ *
+ *  Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
+ *
+ *  Based on corgikbd.c
+ *
+ *  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/types.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/input/matrix_keypad.h>
+
+struct matrix_keypad {
+	const struct matrix_keypad_platform_data *pdata;
+	struct input_dev *input_dev;
+	unsigned short *keycodes;
+
+	uint32_t last_key_state[MATRIX_MAX_COLS];
+	struct delayed_work work;
+	bool scan_pending;
+	bool stopped;
+	spinlock_t lock;
+};
+
+/*
+ * NOTE: normally the GPIO has to be put into HiZ when de-activated to cause
+ * minmal side effect when scanning other columns, here it is configured to
+ * be input, and it should work on most platforms.
+ */
+static void __activate_col(const struct matrix_keypad_platform_data *pdata,
+			   int col, bool on)
+{
+	bool level_on = !pdata->active_low;
+
+	if (on) {
+		gpio_direction_output(pdata->col_gpios[col], level_on);
+	} else {
+		gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
+		gpio_direction_input(pdata->col_gpios[col]);
+	}
+}
+
+static void activate_col(const struct matrix_keypad_platform_data *pdata,
+			 int col, bool on)
+{
+	__activate_col(pdata, col, on);
+
+	if (on && pdata->col_scan_delay_us)
+		udelay(pdata->col_scan_delay_us);
+}
+
+static void activate_all_cols(const struct matrix_keypad_platform_data *pdata,
+			      bool on)
+{
+	int col;
+
+	for (col = 0; col < pdata->num_col_gpios; col++)
+		__activate_col(pdata, col, on);
+}
+
+static bool row_asserted(const struct matrix_keypad_platform_data *pdata,
+			 int row)
+{
+	return gpio_get_value_cansleep(pdata->row_gpios[row]) ?
+			!pdata->active_low : pdata->active_low;
+}
+
+static void enable_row_irqs(struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	for (i = 0; i < pdata->num_row_gpios; i++)
+		enable_irq(gpio_to_irq(pdata->row_gpios[i]));
+}
+
+static void disable_row_irqs(struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	for (i = 0; i < pdata->num_row_gpios; i++)
+		disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
+}
+
+/*
+ * This gets the keys from keyboard and reports it to input subsystem
+ */
+static void matrix_keypad_scan(struct work_struct *work)
+{
+	struct matrix_keypad *keypad =
+		container_of(work, struct matrix_keypad, work.work);
+	struct input_dev *input_dev = keypad->input_dev;
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	uint32_t new_state[MATRIX_MAX_COLS];
+	int row, col, code;
+
+	/* de-activate all columns for scanning */
+	activate_all_cols(pdata, false);
+
+	memset(new_state, 0, sizeof(new_state));
+
+	/* assert each column and read the row status out */
+	for (col = 0; col < pdata->num_col_gpios; col++) {
+
+		activate_col(pdata, col, true);
+
+		for (row = 0; row < pdata->num_row_gpios; row++)
+			new_state[col] |=
+				row_asserted(pdata, row) ? (1 << row) : 0;
+
+		activate_col(pdata, col, false);
+	}
+
+	for (col = 0; col < pdata->num_col_gpios; col++) {
+		uint32_t bits_changed;
+
+		bits_changed = keypad->last_key_state[col] ^ new_state[col];
+		if (bits_changed == 0)
+			continue;
+
+		for (row = 0; row < pdata->num_row_gpios; row++) {
+			if ((bits_changed & (1 << row)) == 0)
+				continue;
+
+			code = (row << 4) + col;
+			input_event(input_dev, EV_MSC, MSC_SCAN, code);
+			input_report_key(input_dev,
+					 keypad->keycodes[code],
+					 new_state[col] & (1 << row));
+		}
+	}
+	input_sync(input_dev);
+
+	memcpy(keypad->last_key_state, new_state, sizeof(new_state));
+
+	activate_all_cols(pdata, true);
+
+	/* Enable IRQs again */
+	spin_lock_irq(&keypad->lock);
+	keypad->scan_pending = false;
+	enable_row_irqs(keypad);
+	spin_unlock_irq(&keypad->lock);
+}
+
+static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
+{
+	struct matrix_keypad *keypad = id;
+	unsigned long flags;
+
+	spin_lock_irqsave(&keypad->lock, flags);
+
+	/*
+	 * See if another IRQ beaten us to it and scheduled the
+	 * scan already. In that case we should not try to
+	 * disable IRQs again.
+	 */
+	if (unlikely(keypad->scan_pending || keypad->stopped))
+		goto out;
+
+	disable_row_irqs(keypad);
+	keypad->scan_pending = true;
+	schedule_delayed_work(&keypad->work,
+		msecs_to_jiffies(keypad->pdata->debounce_ms));
+
+out:
+	spin_unlock_irqrestore(&keypad->lock, flags);
+	return IRQ_HANDLED;
+}
+
+static int matrix_keypad_start(struct input_dev *dev)
+{
+	struct matrix_keypad *keypad = input_get_drvdata(dev);
+
+	keypad->stopped = false;
+	mb();
+
+	/*
+	 * Schedule an immediate key scan to capture current key state;
+	 * columns will be activated and IRQs be enabled after the scan.
+	 */
+	schedule_delayed_work(&keypad->work, 0);
+
+	return 0;
+}
+
+static void matrix_keypad_stop(struct input_dev *dev)
+{
+	struct matrix_keypad *keypad = input_get_drvdata(dev);
+
+	keypad->stopped = true;
+	mb();
+	flush_work(&keypad->work.work);
+	/*
+	 * matrix_keypad_scan() will leave IRQs enabled;
+	 * we should disable them now.
+	 */
+	disable_row_irqs(keypad);
+}
+
+#ifdef CONFIG_PM
+static int matrix_keypad_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	matrix_keypad_stop(keypad->input_dev);
+
+	if (device_may_wakeup(&pdev->dev))
+		for (i = 0; i < pdata->num_row_gpios; i++)
+			enable_irq_wake(gpio_to_irq(pdata->row_gpios[i]));
+
+	return 0;
+}
+
+static int matrix_keypad_resume(struct platform_device *pdev)
+{
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	if (device_may_wakeup(&pdev->dev))
+		for (i = 0; i < pdata->num_row_gpios; i++)
+			disable_irq_wake(gpio_to_irq(pdata->row_gpios[i]));
+
+	matrix_keypad_start(keypad->input_dev);
+
+	return 0;
+}
+#else
+#define matrix_keypad_suspend	NULL
+#define matrix_keypad_resume	NULL
+#endif
+
+static int __devinit init_matrix_gpio(struct platform_device *pdev,
+					struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i, err = -EINVAL;
+
+	/* initialized strobe lines as outputs, activated */
+	for (i = 0; i < pdata->num_col_gpios; i++) {
+		err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
+		if (err) {
+			dev_err(&pdev->dev,
+				"failed to request GPIO%d for COL%d\n",
+				pdata->col_gpios[i], i);
+			goto err_free_cols;
+		}
+
+		gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
+	}
+
+	for (i = 0; i < pdata->num_row_gpios; i++) {
+		err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
+		if (err) {
+			dev_err(&pdev->dev,
+				"failed to request GPIO%d for ROW%d\n",
+				pdata->row_gpios[i], i);
+			goto err_free_rows;
+		}
+
+		gpio_direction_input(pdata->row_gpios[i]);
+	}
+
+	for (i = 0; i < pdata->num_row_gpios; i++) {
+		err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
+				matrix_keypad_interrupt,
+				IRQF_DISABLED |
+				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+				"matrix-keypad", keypad);
+		if (err) {
+			dev_err(&pdev->dev,
+				"Unable to acquire interrupt for GPIO line %i\n",
+				pdata->row_gpios[i]);
+			goto err_free_irqs;
+		}
+	}
+
+	/* initialized as disabled - enabled by input->open */
+	disable_row_irqs(keypad);
+	return 0;
+
+err_free_irqs:
+	while (--i >= 0)
+		free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
+	i = pdata->num_row_gpios;
+err_free_rows:
+	while (--i >= 0)
+		gpio_free(pdata->row_gpios[i]);
+	i = pdata->num_col_gpios;
+err_free_cols:
+	while (--i >= 0)
+		gpio_free(pdata->col_gpios[i]);
+
+	return err;
+}
+
+static int __devinit matrix_keypad_probe(struct platform_device *pdev)
+{
+	const struct matrix_keypad_platform_data *pdata;
+	const struct matrix_keymap_data *keymap_data;
+	struct matrix_keypad *keypad;
+	struct input_dev *input_dev;
+	unsigned short *keycodes;
+	int i;
+	int err;
+
+	pdata = pdev->dev.platform_data;
+	if (!pdata) {
+		dev_err(&pdev->dev, "no platform data defined\n");
+		return -EINVAL;
+	}
+
+	keymap_data = pdata->keymap_data;
+	if (!keymap_data) {
+		dev_err(&pdev->dev, "no keymap data defined\n");
+		return -EINVAL;
+	}
+
+	if (!keymap_data->max_keymap_size) {
+		dev_err(&pdev->dev, "invalid keymap data supplied\n");
+		return -EINVAL;
+	}
+
+	keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
+	keycodes = kzalloc(keymap_data->max_keymap_size *
+				sizeof(keypad->keycodes),
+			   GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!keypad || !keycodes || !input_dev) {
+		err = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	keypad->input_dev = input_dev;
+	keypad->pdata = pdata;
+	keypad->keycodes = keycodes;
+	keypad->stopped = true;
+	INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
+	spin_lock_init(&keypad->lock);
+
+	input_dev->name		= pdev->name;
+	input_dev->id.bustype	= BUS_HOST;
+	input_dev->dev.parent	= &pdev->dev;
+	input_dev->evbit[0]	= BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+	input_dev->open		= matrix_keypad_start;
+	input_dev->close	= matrix_keypad_stop;
+
+	input_dev->keycode	= keycodes;
+	input_dev->keycodesize	= sizeof(*keycodes);
+	input_dev->keycodemax	= keymap_data->max_keymap_size;
+
+	for (i = 0; i < keymap_data->keymap_size; i++) {
+		unsigned int key = keymap_data->keymap[i];
+		unsigned int row = KEY_ROW(key);
+		unsigned int col = KEY_COL(key);
+		unsigned short code = KEY_VAL(key);
+
+		keycodes[(row << 4) + col] = code;
+		__set_bit(code, input_dev->keybit);
+	}
+	__clear_bit(KEY_RESERVED, input_dev->keybit);
+
+	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+	input_set_drvdata(input_dev, keypad);
+
+	err = init_matrix_gpio(pdev, keypad);
+	if (err)
+		goto err_free_mem;
+
+	err = input_register_device(keypad->input_dev);
+	if (err)
+		goto err_free_mem;
+
+	device_init_wakeup(&pdev->dev, pdata->wakeup);
+	platform_set_drvdata(pdev, keypad);
+
+	return 0;
+
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(keycodes);
+	kfree(keypad);
+	return err;
+}
+
+static int __devexit matrix_keypad_remove(struct platform_device *pdev)
+{
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	device_init_wakeup(&pdev->dev, 0);
+
+	for (i = 0; i < pdata->num_row_gpios; i++) {
+		free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
+		gpio_free(pdata->row_gpios[i]);
+	}
+
+	for (i = 0; i < pdata->num_col_gpios; i++)
+		gpio_free(pdata->col_gpios[i]);
+
+	input_unregister_device(keypad->input_dev);
+	platform_set_drvdata(pdev, NULL);
+	kfree(keypad->keycodes);
+	kfree(keypad);
+
+	return 0;
+}
+
+static struct platform_driver matrix_keypad_driver = {
+	.probe		= matrix_keypad_probe,
+	.remove		= __devexit_p(matrix_keypad_remove),
+	.suspend	= matrix_keypad_suspend,
+	.resume		= matrix_keypad_resume,
+	.driver		= {
+		.name	= "matrix-keypad",
+		.owner	= THIS_MODULE,
+	},
+};
+
+static int __init matrix_keypad_init(void)
+{
+	return platform_driver_register(&matrix_keypad_driver);
+}
+
+static void __exit matrix_keypad_exit(void)
+{
+	platform_driver_unregister(&matrix_keypad_driver);
+}
+
+module_init(matrix_keypad_init);
+module_exit(matrix_keypad_exit);
+
+MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
+MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:matrix-keypad");