1 files changed, 586 insertions, 0 deletions

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
new file mode 100644
index 000000000..7dd3f3eda
--- /dev/null
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -0,0 +1,586 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  GPIO driven matrix keyboard driver
+ *
+ *  Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
+ *
+ *  Based on corgikbd.c
+ */
+
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_device.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>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+
+struct matrix_keypad {
+	const struct matrix_keypad_platform_data *pdata;
+	struct input_dev *input_dev;
+	unsigned int row_shift;
+
+	DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
+
+	uint32_t last_key_state[MATRIX_MAX_COLS];
+	struct delayed_work work;
+	spinlock_t lock;
+	bool scan_pending;
+	bool stopped;
+	bool gpio_all_disabled;
+};
+
+/*
+ * NOTE: If drive_inactive_cols is false, then the GPIO has to be put into
+ * HiZ when de-activated to cause minmal side effect when scanning other
+ * columns. In that case it is configured here to be input, otherwise it is
+ * driven with the inactive value.
+ */
+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);
+		if (!pdata->drive_inactive_cols)
+			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;
+
+	if (pdata->clustered_irq > 0)
+		enable_irq(pdata->clustered_irq);
+	else {
+		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;
+
+	if (pdata->clustered_irq > 0)
+		disable_irq_nosync(pdata->clustered_irq);
+	else {
+		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 unsigned short *keycodes = input_dev->keycode;
+	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 = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
+			input_event(input_dev, EV_MSC, MSC_SCAN, code);
+			input_report_key(input_dev,
+					 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);
+
+	spin_lock_irq(&keypad->lock);
+	keypad->stopped = true;
+	spin_unlock_irq(&keypad->lock);
+
+	flush_delayed_work(&keypad->work);
+	/*
+	 * matrix_keypad_scan() will leave IRQs enabled;
+	 * we should disable them now.
+	 */
+	disable_row_irqs(keypad);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	unsigned int gpio;
+	int i;
+
+	if (pdata->clustered_irq > 0) {
+		if (enable_irq_wake(pdata->clustered_irq) == 0)
+			keypad->gpio_all_disabled = true;
+	} else {
+
+		for (i = 0; i < pdata->num_row_gpios; i++) {
+			if (!test_bit(i, keypad->disabled_gpios)) {
+				gpio = pdata->row_gpios[i];
+
+				if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
+					__set_bit(i, keypad->disabled_gpios);
+			}
+		}
+	}
+}
+
+static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	unsigned int gpio;
+	int i;
+
+	if (pdata->clustered_irq > 0) {
+		if (keypad->gpio_all_disabled) {
+			disable_irq_wake(pdata->clustered_irq);
+			keypad->gpio_all_disabled = false;
+		}
+	} else {
+		for (i = 0; i < pdata->num_row_gpios; i++) {
+			if (test_and_clear_bit(i, keypad->disabled_gpios)) {
+				gpio = pdata->row_gpios[i];
+				disable_irq_wake(gpio_to_irq(gpio));
+			}
+		}
+	}
+}
+
+static int matrix_keypad_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+
+	matrix_keypad_stop(keypad->input_dev);
+
+	if (device_may_wakeup(&pdev->dev))
+		matrix_keypad_enable_wakeup(keypad);
+
+	return 0;
+}
+
+static int matrix_keypad_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+
+	if (device_may_wakeup(&pdev->dev))
+		matrix_keypad_disable_wakeup(keypad);
+
+	matrix_keypad_start(keypad->input_dev);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
+			 matrix_keypad_suspend, matrix_keypad_resume);
+
+static int matrix_keypad_init_gpio(struct platform_device *pdev,
+				   struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i, err;
+
+	/* 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]);
+	}
+
+	if (pdata->clustered_irq > 0) {
+		err = request_any_context_irq(pdata->clustered_irq,
+				matrix_keypad_interrupt,
+				pdata->clustered_irq_flags,
+				"matrix-keypad", keypad);
+		if (err < 0) {
+			dev_err(&pdev->dev,
+				"Unable to acquire clustered interrupt\n");
+			goto err_free_rows;
+		}
+	} else {
+		for (i = 0; i < pdata->num_row_gpios; i++) {
+			err = request_any_context_irq(
+					gpio_to_irq(pdata->row_gpios[i]),
+					matrix_keypad_interrupt,
+					IRQF_TRIGGER_RISING |
+					IRQF_TRIGGER_FALLING,
+					"matrix-keypad", keypad);
+			if (err < 0) {
+				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 void matrix_keypad_free_gpio(struct matrix_keypad *keypad)
+{
+	const struct matrix_keypad_platform_data *pdata = keypad->pdata;
+	int i;
+
+	if (pdata->clustered_irq > 0) {
+		free_irq(pdata->clustered_irq, keypad);
+	} else {
+		for (i = 0; i < pdata->num_row_gpios; i++)
+			free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
+	}
+
+	for (i = 0; i < pdata->num_row_gpios; i++)
+		gpio_free(pdata->row_gpios[i]);
+
+	for (i = 0; i < pdata->num_col_gpios; i++)
+		gpio_free(pdata->col_gpios[i]);
+}
+
+#ifdef CONFIG_OF
+static struct matrix_keypad_platform_data *
+matrix_keypad_parse_dt(struct device *dev)
+{
+	struct matrix_keypad_platform_data *pdata;
+	struct device_node *np = dev->of_node;
+	unsigned int *gpios;
+	int ret, i, nrow, ncol;
+
+	if (!np) {
+		dev_err(dev, "device lacks DT data\n");
+		return ERR_PTR(-ENODEV);
+	}
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		dev_err(dev, "could not allocate memory for platform data\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	pdata->num_row_gpios = nrow = gpiod_count(dev, "row");
+	pdata->num_col_gpios = ncol = gpiod_count(dev, "col");
+	if (nrow < 0 || ncol < 0) {
+		dev_err(dev, "number of keypad rows/columns not specified\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (of_get_property(np, "linux,no-autorepeat", NULL))
+		pdata->no_autorepeat = true;
+
+	pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
+			of_property_read_bool(np, "linux,wakeup"); /* legacy */
+
+	if (of_get_property(np, "gpio-activelow", NULL))
+		pdata->active_low = true;
+
+	pdata->drive_inactive_cols =
+		of_property_read_bool(np, "drive-inactive-cols");
+
+	of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms);
+	of_property_read_u32(np, "col-scan-delay-us",
+						&pdata->col_scan_delay_us);
+
+	gpios = devm_kcalloc(dev,
+			     pdata->num_row_gpios + pdata->num_col_gpios,
+			     sizeof(unsigned int),
+			     GFP_KERNEL);
+	if (!gpios) {
+		dev_err(dev, "could not allocate memory for gpios\n");
+		return ERR_PTR(-ENOMEM);
+	}
+
+	for (i = 0; i < nrow; i++) {
+		ret = of_get_named_gpio(np, "row-gpios", i);
+		if (ret < 0)
+			return ERR_PTR(ret);
+		gpios[i] = ret;
+	}
+
+	for (i = 0; i < ncol; i++) {
+		ret = of_get_named_gpio(np, "col-gpios", i);
+		if (ret < 0)
+			return ERR_PTR(ret);
+		gpios[nrow + i] = ret;
+	}
+
+	pdata->row_gpios = gpios;
+	pdata->col_gpios = &gpios[pdata->num_row_gpios];
+
+	return pdata;
+}
+#else
+static inline struct matrix_keypad_platform_data *
+matrix_keypad_parse_dt(struct device *dev)
+{
+	dev_err(dev, "no platform data defined\n");
+
+	return ERR_PTR(-EINVAL);
+}
+#endif
+
+static int matrix_keypad_probe(struct platform_device *pdev)
+{
+	const struct matrix_keypad_platform_data *pdata;
+	struct matrix_keypad *keypad;
+	struct input_dev *input_dev;
+	int err;
+
+	pdata = dev_get_platdata(&pdev->dev);
+	if (!pdata) {
+		pdata = matrix_keypad_parse_dt(&pdev->dev);
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
+	} else if (!pdata->keymap_data) {
+		dev_err(&pdev->dev, "no keymap data defined\n");
+		return -EINVAL;
+	}
+
+	keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!keypad || !input_dev) {
+		err = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	keypad->input_dev = input_dev;
+	keypad->pdata = pdata;
+	keypad->row_shift = get_count_order(pdata->num_col_gpios);
+	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->open		= matrix_keypad_start;
+	input_dev->close	= matrix_keypad_stop;
+
+	err = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
+					 pdata->num_row_gpios,
+					 pdata->num_col_gpios,
+					 NULL, input_dev);
+	if (err) {
+		dev_err(&pdev->dev, "failed to build keymap\n");
+		goto err_free_mem;
+	}
+
+	if (!pdata->no_autorepeat)
+		__set_bit(EV_REP, input_dev->evbit);
+	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+	input_set_drvdata(input_dev, keypad);
+
+	err = matrix_keypad_init_gpio(pdev, keypad);
+	if (err)
+		goto err_free_mem;
+
+	err = input_register_device(keypad->input_dev);
+	if (err)
+		goto err_free_gpio;
+
+	device_init_wakeup(&pdev->dev, pdata->wakeup);
+	platform_set_drvdata(pdev, keypad);
+
+	return 0;
+
+err_free_gpio:
+	matrix_keypad_free_gpio(keypad);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(keypad);
+	return err;
+}
+
+static int matrix_keypad_remove(struct platform_device *pdev)
+{
+	struct matrix_keypad *keypad = platform_get_drvdata(pdev);
+
+	matrix_keypad_free_gpio(keypad);
+	input_unregister_device(keypad->input_dev);
+	kfree(keypad);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id matrix_keypad_dt_match[] = {
+	{ .compatible = "gpio-matrix-keypad" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
+#endif
+
+static struct platform_driver matrix_keypad_driver = {
+	.probe		= matrix_keypad_probe,
+	.remove		= matrix_keypad_remove,
+	.driver		= {
+		.name	= "matrix-keypad",
+		.pm	= &matrix_keypad_pm_ops,
+		.of_match_table = of_match_ptr(matrix_keypad_dt_match),
+	},
+};
+module_platform_driver(matrix_keypad_driver);
+
+MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
+MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:matrix-keypad");