3 files changed, 604 insertions, 0 deletions

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index c72283c6916f..616a3916d187 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -292,6 +292,15 @@ config KEYBOARD_MAX7359
           To compile this driver as a module, choose M here: the
           module will be called max7359_keypad.
 
+config KEYBOARD_IMX
+        tristate "IMX keypad support"
+        depends on ARCH_MXC
+        help
+          Enable support for IMX keypad port.
+
+          To compile this driver as a module, choose M here: the
+          module will be called imx_keypad.
+
 config KEYBOARD_NEWTON
         tristate "Newton keyboard"
         select SERIO
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 78654ef65206..706c6b5ed5f4 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_KEYBOARD_EP93XX)		+= ep93xx_keypad.o
 obj-$(CONFIG_KEYBOARD_GPIO)             += gpio_keys.o
 obj-$(CONFIG_KEYBOARD_HIL)              += hil_kbd.o
 obj-$(CONFIG_KEYBOARD_HIL_OLD)          += hilkbd.o
+obj-$(CONFIG_KEYBOARD_IMX)              += imx_keypad.o
 obj-$(CONFIG_KEYBOARD_HP6XX)            += jornada680_kbd.o
 obj-$(CONFIG_KEYBOARD_HP7XX)            += jornada720_kbd.o
 obj-$(CONFIG_KEYBOARD_LKKBD)            += lkkbd.o
diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
new file mode 100644
index 000000000000..2ee5b798024d
--- /dev/null
+++ b/drivers/input/keyboard/imx_keypad.c
@@ -0,0 +1,594 @@
+/*
+ * Driver for the IMX keypad port.
+ * Copyright (C) 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com>
+ *
+ * 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.
+ *
+ * <<Power management needs to be implemented>>.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/timer.h>
+
+/*
+ * Keypad Controller registers (halfword)
+ */
+#define KPCR            0x00 /* Keypad Control Register */
+
+#define KPSR            0x02 /* Keypad Status Register */
+#define KBD_STAT_KPKD   (0x1 << 0) /* Key Press Interrupt Status bit (w1c) */
+#define KBD_STAT_KPKR   (0x1 << 1) /* Key Release Interrupt Status bit (w1c) */
+#define KBD_STAT_KDSC   (0x1 << 2) /* Key Depress Synch Chain Status bit (w1c)*/
+#define KBD_STAT_KRSS   (0x1 << 3) /* Key Release Synch Status bit (w1c)*/
+#define KBD_STAT_KDIE   (0x1 << 8) /* Key Depress Interrupt Enable Status bit */
+#define KBD_STAT_KRIE   (0x1 << 9) /* Key Release Interrupt Enable */
+#define KBD_STAT_KPPEN  (0x1 << 10) /* Keypad Clock Enable */
+
+#define KDDR            0x04 /* Keypad Data Direction Register */
+#define KPDR            0x06 /* Keypad Data Register */
+
+#define MAX_MATRIX_KEY_ROWS     8
+#define MAX_MATRIX_KEY_COLS     8
+#define MATRIX_ROW_SHIFT        3
+
+#define MAX_MATRIX_KEY_NUM      (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
+
+struct imx_keypad {
+
+        struct clk *clk;
+        struct input_dev *input_dev;
+        void __iomem *mmio_base;
+
+        int                     irq;
+        struct timer_list       check_matrix_timer;
+
+        /*
+         * The matrix is stable only if no changes are detected after
+         * IMX_KEYPAD_SCANS_FOR_STABILITY scans
+         */
+#define IMX_KEYPAD_SCANS_FOR_STABILITY 3
+        int                     stable_count;
+
+        bool                    enabled;
+
+        /* Masks for enabled rows/cols */
+        unsigned short          rows_en_mask;
+        unsigned short          cols_en_mask;
+
+        unsigned short          keycodes[MAX_MATRIX_KEY_NUM];
+
+        /*
+         * Matrix states:
+         * -stable: achieved after a complete debounce process.
+         * -unstable: used in the debouncing process.
+         */
+        unsigned short          matrix_stable_state[MAX_MATRIX_KEY_COLS];
+        unsigned short          matrix_unstable_state[MAX_MATRIX_KEY_COLS];
+};
+
+/* Scan the matrix and return the new state in *matrix_volatile_state. */
+static void imx_keypad_scan_matrix(struct imx_keypad *keypad,
+                                  unsigned short *matrix_volatile_state)
+{
+        int col;
+        unsigned short reg_val;
+
+        for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
+                if ((keypad->cols_en_mask & (1 << col)) == 0)
+                        continue;
+                /*
+                 * Discharge keypad capacitance:
+                 * 2. write 1s on column data.
+                 * 3. configure columns as totem-pole to discharge capacitance.
+                 * 4. configure columns as open-drain.
+                 */
+                reg_val = readw(keypad->mmio_base + KPDR);
+                reg_val |= 0xff00;
+                writew(reg_val, keypad->mmio_base + KPDR);
+
+                reg_val = readw(keypad->mmio_base + KPCR);
+                reg_val &= ~((keypad->cols_en_mask & 0xff) << 8);
+                writew(reg_val, keypad->mmio_base + KPCR);
+
+                udelay(2);
+
+                reg_val = readw(keypad->mmio_base + KPCR);
+                reg_val |= (keypad->cols_en_mask & 0xff) << 8;
+                writew(reg_val, keypad->mmio_base + KPCR);
+
+                /*
+                 * 5. Write a single column to 0, others to 1.
+                 * 6. Sample row inputs and save data.
+                 * 7. Repeat steps 2 - 6 for remaining columns.
+                 */
+                reg_val = readw(keypad->mmio_base + KPDR);
+                reg_val &= ~(1 << (8 + col));
+                writew(reg_val, keypad->mmio_base + KPDR);
+
+                /*
+                 * Delay added to avoid propagating the 0 from column to row
+                 * when scanning.
+                 */
+                udelay(5);
+
+                /*
+                 * 1s in matrix_volatile_state[col] means key pressures
+                 * throw data from non enabled rows.
+                 */
+                reg_val = readw(keypad->mmio_base + KPDR);
+                matrix_volatile_state[col] = (~reg_val) & keypad->rows_en_mask;
+        }
+
+        /*
+         * Return in standby mode:
+         * 9. write 0s to columns
+         */
+        reg_val = readw(keypad->mmio_base + KPDR);
+        reg_val &= 0x00ff;
+        writew(reg_val, keypad->mmio_base + KPDR);
+}
+
+/*
+ * Compare the new matrix state (volatile) with the stable one stored in
+ * keypad->matrix_stable_state and fire events if changes are detected.
+ */
+static void imx_keypad_fire_events(struct imx_keypad *keypad,
+                                   unsigned short *matrix_volatile_state)
+{
+        struct input_dev *input_dev = keypad->input_dev;
+        int row, col;
+
+        for (col = 0; col < MAX_MATRIX_KEY_COLS; col++) {
+                unsigned short bits_changed;
+                int code;
+
+                if ((keypad->cols_en_mask & (1 << col)) == 0)
+                        continue; /* Column is not enabled */
+
+                bits_changed = keypad->matrix_stable_state[col] ^
+                                                matrix_volatile_state[col];
+
+                if (bits_changed == 0)
+                        continue; /* Column does not contain changes */
+
+                for (row = 0; row < MAX_MATRIX_KEY_ROWS; row++) {
+                        if ((keypad->rows_en_mask & (1 << row)) == 0)
+                                continue; /* Row is not enabled */
+                        if ((bits_changed & (1 << row)) == 0)
+                                continue; /* Row does not contain changes */
+
+                        code = MATRIX_SCAN_CODE(row, col, MATRIX_ROW_SHIFT);
+                        input_event(input_dev, EV_MSC, MSC_SCAN, code);
+                        input_report_key(input_dev, keypad->keycodes[code],
+                                matrix_volatile_state[col] & (1 << row));
+                        dev_dbg(&input_dev->dev, "Event code: %d, val: %d",
+                                keypad->keycodes[code],
+                                matrix_volatile_state[col] & (1 << row));
+                }
+        }
+        input_sync(input_dev);
+}
+
+/*
+ * imx_keypad_check_for_events is the timer handler.
+ */
+static void imx_keypad_check_for_events(unsigned long data)
+{
+        struct imx_keypad *keypad = (struct imx_keypad *) data;
+        unsigned short matrix_volatile_state[MAX_MATRIX_KEY_COLS];
+        unsigned short reg_val;
+        bool state_changed, is_zero_matrix;
+        int i;
+
+        memset(matrix_volatile_state, 0, sizeof(matrix_volatile_state));
+
+        imx_keypad_scan_matrix(keypad, matrix_volatile_state);
+
+        state_changed = false;
+        for (i = 0; i < MAX_MATRIX_KEY_COLS; i++) {
+                if ((keypad->cols_en_mask & (1 << i)) == 0)
+                        continue;
+
+                if (keypad->matrix_unstable_state[i] ^ matrix_volatile_state[i]) {
+                        state_changed = true;
+                        break;
+                }
+        }
+
+        /*
+         * If the matrix state is changed from the previous scan
+         *   (Re)Begin the debouncing process, saving the new state in
+         *    keypad->matrix_unstable_state.
+         * else
+         *   Increase the count of number of scans with a stable state.
+         */
+        if (state_changed) {
+                memcpy(keypad->matrix_unstable_state, matrix_volatile_state,
+                        sizeof(matrix_volatile_state));
+                keypad->stable_count = 0;
+        } else
+                keypad->stable_count++;
+
+        /*
+         * If the matrix is not as stable as we want reschedule scan
+         * in the near future.
+         */
+        if (keypad->stable_count < IMX_KEYPAD_SCANS_FOR_STABILITY) {
+                mod_timer(&keypad->check_matrix_timer,
+                          jiffies + msecs_to_jiffies(10));
+                return;
+        }
+
+        /*
+         * If the matrix state is stable, fire the events and save the new
+         * stable state. Note, if the matrix is kept stable for longer
+         * (keypad->stable_count > IMX_KEYPAD_SCANS_FOR_STABILITY) all
+         * events have already been generated.
+         */
+        if (keypad->stable_count == IMX_KEYPAD_SCANS_FOR_STABILITY) {
+                imx_keypad_fire_events(keypad, matrix_volatile_state);
+
+                memcpy(keypad->matrix_stable_state, matrix_volatile_state,
+                        sizeof(matrix_volatile_state));
+        }
+
+        is_zero_matrix = true;
+        for (i = 0; i < MAX_MATRIX_KEY_COLS; i++) {
+                if (matrix_volatile_state[i] != 0) {
+                        is_zero_matrix = false;
+                        break;
+                }
+        }
+
+
+        if (is_zero_matrix) {
+                /*
+                 * All keys have been released. Enable only the KDI
+                 * interrupt for future key presses (clear the KDI
+                 * status bit and its sync chain before that).
+                 */
+                reg_val = readw(keypad->mmio_base + KPSR);
+                reg_val |= KBD_STAT_KPKD | KBD_STAT_KDSC;
+                writew(reg_val, keypad->mmio_base + KPSR);
+
+                reg_val = readw(keypad->mmio_base + KPSR);
+                reg_val |= KBD_STAT_KDIE;
+                reg_val &= ~KBD_STAT_KRIE;
+                writew(reg_val, keypad->mmio_base + KPSR);
+        } else {
+                /*
+                 * Some keys are still pressed. Schedule a rescan in
+                 * attempt to detect multiple key presses and enable
+                 * the KRI interrupt to react quickly to key release
+                 * event.
+                 */
+                mod_timer(&keypad->check_matrix_timer,
+                          jiffies + msecs_to_jiffies(60));
+
+                reg_val = readw(keypad->mmio_base + KPSR);
+                reg_val |= KBD_STAT_KPKR | KBD_STAT_KRSS;
+                writew(reg_val, keypad->mmio_base + KPSR);
+
+                reg_val = readw(keypad->mmio_base + KPSR);
+                reg_val |= KBD_STAT_KRIE;
+                reg_val &= ~KBD_STAT_KDIE;
+                writew(reg_val, keypad->mmio_base + KPSR);
+        }
+}
+
+static irqreturn_t imx_keypad_irq_handler(int irq, void *dev_id)
+{
+        struct imx_keypad *keypad = dev_id;
+        unsigned short reg_val;
+
+        reg_val = readw(keypad->mmio_base + KPSR);
+
+        /* Disable both interrupt types */
+        reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+        /* Clear interrupts status bits */
+        reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD;
+        writew(reg_val, keypad->mmio_base + KPSR);
+
+        if (keypad->enabled) {
+                /* The matrix is supposed to be changed */
+                keypad->stable_count = 0;
+
+                /* Schedule the scanning procedure near in the future */
+                mod_timer(&keypad->check_matrix_timer,
+                          jiffies + msecs_to_jiffies(2));
+        }
+
+        return IRQ_HANDLED;
+}
+
+static void imx_keypad_config(struct imx_keypad *keypad)
+{
+        unsigned short reg_val;
+
+        /*
+         * Include enabled rows in interrupt generation (KPCR[7:0])
+         * Configure keypad columns as open-drain (KPCR[15:8])
+         */
+        reg_val = readw(keypad->mmio_base + KPCR);
+        reg_val |= keypad->rows_en_mask & 0xff;         /* rows */
+        reg_val |= (keypad->cols_en_mask & 0xff) << 8;  /* cols */
+        writew(reg_val, keypad->mmio_base + KPCR);
+
+        /* Write 0's to KPDR[15:8] (Colums) */
+        reg_val = readw(keypad->mmio_base + KPDR);
+        reg_val &= 0x00ff;
+        writew(reg_val, keypad->mmio_base + KPDR);
+
+        /* Configure columns as output, rows as input (KDDR[15:0]) */
+        writew(0xff00, keypad->mmio_base + KDDR);
+
+        /*
+         * Clear Key Depress and Key Release status bit.
+         * Clear both synchronizer chain.
+         */
+        reg_val = readw(keypad->mmio_base + KPSR);
+        reg_val |= KBD_STAT_KPKR | KBD_STAT_KPKD |
+                   KBD_STAT_KDSC | KBD_STAT_KRSS;
+        writew(reg_val, keypad->mmio_base + KPSR);
+
+        /* Enable KDI and disable KRI (avoid false release events). */
+        reg_val |= KBD_STAT_KDIE;
+        reg_val &= ~KBD_STAT_KRIE;
+        writew(reg_val, keypad->mmio_base + KPSR);
+}
+
+static void imx_keypad_inhibit(struct imx_keypad *keypad)
+{
+        unsigned short reg_val;
+
+        /* Inhibit KDI and KRI interrupts. */
+        reg_val = readw(keypad->mmio_base + KPSR);
+        reg_val &= ~(KBD_STAT_KRIE | KBD_STAT_KDIE);
+        writew(reg_val, keypad->mmio_base + KPSR);
+
+        /* Colums as open drain and disable all rows */
+        writew(0xff00, keypad->mmio_base + KPCR);
+}
+
+static void imx_keypad_close(struct input_dev *dev)
+{
+        struct imx_keypad *keypad = input_get_drvdata(dev);
+
+        dev_dbg(&dev->dev, ">%s\n", __func__);
+
+        /* Mark keypad as being inactive */
+        keypad->enabled = false;
+        synchronize_irq(keypad->irq);
+        del_timer_sync(&keypad->check_matrix_timer);
+
+        imx_keypad_inhibit(keypad);
+
+        /* Disable clock unit */
+        clk_disable(keypad->clk);
+}
+
+static int imx_keypad_open(struct input_dev *dev)
+{
+        struct imx_keypad *keypad = input_get_drvdata(dev);
+
+        dev_dbg(&dev->dev, ">%s\n", __func__);
+
+        /* We became active from now */
+        keypad->enabled = true;
+
+        /* Enable the kpp clock */
+        clk_enable(keypad->clk);
+        imx_keypad_config(keypad);
+
+        /* Sanity control, not all the rows must be actived now. */
+        if ((readw(keypad->mmio_base + KPDR) & keypad->rows_en_mask) == 0) {
+                dev_err(&dev->dev,
+                        "too many keys pressed, control pins initialisation\n");
+                goto open_err;
+        }
+
+        return 0;
+
+open_err:
+        imx_keypad_close(dev);
+        return -EIO;
+}
+
+static int __devinit imx_keypad_probe(struct platform_device *pdev)
+{
+        const struct matrix_keymap_data *keymap_data = pdev->dev.platform_data;
+        struct imx_keypad *keypad;
+        struct input_dev *input_dev;
+        struct resource *res;
+        int irq, error, i;
+
+        if (keymap_data == NULL) {
+                dev_err(&pdev->dev, "no keymap defined\n");
+                return -EINVAL;
+        }
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0) {
+                dev_err(&pdev->dev, "no irq defined in platform data\n");
+                return -EINVAL;
+        }
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (res == NULL) {
+                dev_err(&pdev->dev, "no I/O memory defined in platform data\n");
+                return -EINVAL;
+        }
+
+        res = request_mem_region(res->start, resource_size(res), pdev->name);
+        if (res == NULL) {
+                dev_err(&pdev->dev, "failed to request I/O memory\n");
+                return -EBUSY;
+        }
+
+        input_dev = input_allocate_device();
+        if (!input_dev) {
+                dev_err(&pdev->dev, "failed to allocate the input device\n");
+                error = -ENOMEM;
+                goto failed_rel_mem;
+        }
+
+        keypad = kzalloc(sizeof(struct imx_keypad), GFP_KERNEL);
+        if (!keypad) {
+                dev_err(&pdev->dev, "not enough memory for driver data\n");
+                error = -ENOMEM;
+                goto failed_free_input;
+        }
+
+        keypad->input_dev = input_dev;
+        keypad->irq = irq;
+        keypad->stable_count = 0;
+
+        setup_timer(&keypad->check_matrix_timer,
+                    imx_keypad_check_for_events, (unsigned long) keypad);
+
+        keypad->mmio_base = ioremap(res->start, resource_size(res));
+        if (keypad->mmio_base == NULL) {
+                dev_err(&pdev->dev, "failed to remap I/O memory\n");
+                error = -ENOMEM;
+                goto failed_free_priv;
+        }
+
+        keypad->clk = clk_get(&pdev->dev, "kpp");
+        if (IS_ERR(keypad->clk)) {
+                dev_err(&pdev->dev, "failed to get keypad clock\n");
+                error = PTR_ERR(keypad->clk);
+                goto failed_unmap;
+        }
+
+        /* Search for rows and cols enabled */
+        for (i = 0; i < keymap_data->keymap_size; i++) {
+                keypad->rows_en_mask |= 1 << KEY_ROW(keymap_data->keymap[i]);
+                keypad->cols_en_mask |= 1 << KEY_COL(keymap_data->keymap[i]);
+        }
+
+        if (keypad->rows_en_mask > ((1 << MAX_MATRIX_KEY_ROWS) - 1) ||
+           keypad->cols_en_mask > ((1 << MAX_MATRIX_KEY_COLS) - 1)) {
+                dev_err(&pdev->dev,
+                        "invalid key data (too many rows or colums)\n");
+                error = -EINVAL;
+                goto failed_clock_put;
+        }
+        dev_dbg(&pdev->dev, "enabled rows mask: %x\n", keypad->rows_en_mask);
+        dev_dbg(&pdev->dev, "enabled cols mask: %x\n", keypad->cols_en_mask);
+
+        /* Init the Input device */
+        input_dev->name = pdev->name;
+        input_dev->id.bustype = BUS_HOST;
+        input_dev->dev.parent = &pdev->dev;
+        input_dev->open = imx_keypad_open;
+        input_dev->close = imx_keypad_close;
+        input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+        input_dev->keycode = keypad->keycodes;
+        input_dev->keycodesize = sizeof(keypad->keycodes[0]);
+        input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
+
+        matrix_keypad_build_keymap(keymap_data, MATRIX_ROW_SHIFT,
+                                keypad->keycodes, input_dev->keybit);
+
+        input_set_capability(input_dev, EV_MSC, MSC_SCAN);
+        input_set_drvdata(input_dev, keypad);
+
+        /* Ensure that the keypad will stay dormant until opened */
+        imx_keypad_inhibit(keypad);
+
+        error = request_irq(irq, imx_keypad_irq_handler, IRQF_DISABLED,
+                            pdev->name, keypad);
+        if (error) {
+                dev_err(&pdev->dev, "failed to request IRQ\n");
+                goto failed_clock_put;
+        }
+
+        /* Register the input device */
+        error = input_register_device(input_dev);
+        if (error) {
+                dev_err(&pdev->dev, "failed to register input device\n");
+                goto failed_free_irq;
+        }
+
+        platform_set_drvdata(pdev, keypad);
+        device_init_wakeup(&pdev->dev, 1);
+
+        return 0;
+
+failed_free_irq:
+        free_irq(irq, pdev);
+failed_clock_put:
+        clk_put(keypad->clk);
+failed_unmap:
+        iounmap(keypad->mmio_base);
+failed_free_priv:
+        kfree(keypad);
+failed_free_input:
+        input_free_device(input_dev);
+failed_rel_mem:
+        release_mem_region(res->start, resource_size(res));
+        return error;
+}
+
+static int __devexit imx_keypad_remove(struct platform_device *pdev)
+{
+        struct imx_keypad *keypad = platform_get_drvdata(pdev);
+        struct resource *res;
+
+        dev_dbg(&pdev->dev, ">%s\n", __func__);
+
+        platform_set_drvdata(pdev, NULL);
+
+        input_unregister_device(keypad->input_dev);
+
+        free_irq(keypad->irq, keypad);
+        clk_put(keypad->clk);
+
+        iounmap(keypad->mmio_base);
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        release_mem_region(res->start, resource_size(res));
+
+        kfree(keypad);
+
+        return 0;
+}
+
+static struct platform_driver imx_keypad_driver = {
+        .driver         = {
+                .name   = "imx-keypad",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = imx_keypad_probe,
+        .remove         = __devexit_p(imx_keypad_remove),
+};
+
+static int __init imx_keypad_init(void)
+{
+        return platform_driver_register(&imx_keypad_driver);
+}
+
+static void __exit imx_keypad_exit(void)
+{
+        platform_driver_unregister(&imx_keypad_driver);
+}
+
+module_init(imx_keypad_init);
+module_exit(imx_keypad_exit);
+
+MODULE_AUTHOR("Alberto Panizzo <maramaopercheseimorto@gmail.com>");
+MODULE_DESCRIPTION("IMX Keypad Port Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:imx-keypad");