1 files changed, 444 insertions, 0 deletions

diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
new file mode 100644
index 000000000000..91cfe5170265
--- /dev/null
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -0,0 +1,444 @@
+/*
+ *  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;
+        unsigned int row_shift;
+
+        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 = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
+                        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;
+        unsigned int row_shift;
+        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;
+        }
+
+        row_shift = get_count_order(pdata->num_col_gpios);
+
+        keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
+        keycodes = kzalloc((pdata->num_row_gpios << row_shift) *
+                                sizeof(*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->row_shift = row_shift;
+        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   = pdata->num_row_gpios << row_shift;
+
+        matrix_keypad_build_keymap(keymap_data, row_shift,
+                                   input_dev->keycode, 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");