Input: add matrix keypad driver for Cirrus EP93xx

This is a keyboard driver for the Cirrus Logic EP93xx keypad matrix
peripheral. This driver is based on the pxa27x_keypad driver.

[dtor@mail.ru: Plug in input_dev->keycode so keymap can be changed
		from userspace.]
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

4 files changed, 523 insertions, 0 deletions

diff --git a/arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h b/arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h
new file mode 100644
index 000000000000..83f31cd0a274
--- /dev/null
+++ b/arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h
@@ -0,0 +1,42 @@
+/*
+ * arch/arm/mach-ep93xx/include/mach/ep93xx_keypad.h
+ */
+
+#ifndef __ASM_ARCH_EP93XX_KEYPAD_H
+#define __ASM_ARCH_EP93XX_KEYPAD_H
+
+#define MAX_MATRIX_KEY_ROWS             (8)
+#define MAX_MATRIX_KEY_COLS             (8)
+
+/* flags for the ep93xx_keypad driver */
+#define EP93XX_KEYPAD_DISABLE_3_KEY     (1<<0)  /* disable 3-key reset */
+#define EP93XX_KEYPAD_DIAG_MODE         (1<<1)  /* diagnostic mode */
+#define EP93XX_KEYPAD_BACK_DRIVE        (1<<2)  /* back driving mode */
+#define EP93XX_KEYPAD_TEST_MODE         (1<<3)  /* scan only column 0 */
+#define EP93XX_KEYPAD_KDIV              (1<<4)  /* 1/4 clock or 1/16 clock */
+#define EP93XX_KEYPAD_AUTOREPEAT        (1<<5)  /* enable key autorepeat */
+
+/**
+ * struct ep93xx_keypad_platform_data - platform specific device structure
+ * @matrix_key_rows:            number of rows in the keypad matrix
+ * @matrix_key_cols:            number of columns in the keypad matrix
+ * @matrix_key_map:             array of keycodes defining the keypad matrix
+ * @matrix_key_map_size:        ARRAY_SIZE(matrix_key_map)
+ * @debounce:                   debounce start count; terminal count is 0xff
+ * @prescale:                   row/column counter pre-scaler load value
+ * @flags:                      see above
+ */
+struct ep93xx_keypad_platform_data {
+        unsigned int    matrix_key_rows;
+        unsigned int    matrix_key_cols;
+        unsigned int    *matrix_key_map;
+        int             matrix_key_map_size;
+        unsigned int    debounce;
+        unsigned int    prescale;
+        unsigned int    flags;
+};
+
+/* macro for creating the matrix_key_map table */
+#define KEY(row, col, val)      (((row) << 28) | ((col) << 24) | (val))
+
+#endif  /* __ASM_ARCH_EP93XX_KEYPAD_H */
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 35561689ff38..76407df17cd7 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -332,4 +332,14 @@ config KEYBOARD_SH_KEYSC
 
           To compile this driver as a module, choose M here: the
           module will be called sh_keysc.
++
+config KEYBOARD_EP93XX
+        tristate "EP93xx Matrix Keypad support"
+        depends on ARCH_EP93XX
+        help
+          Say Y here to enable the matrix keypad on the Cirrus EP93XX.
+
+          To compile this driver as a module, choose M here: the
+          module will be called ep93xx_keypad.
+
 endif
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 36351e1190f9..13ba9c954938 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -28,3 +28,4 @@ obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
 obj-$(CONFIG_KEYBOARD_MAPLE)            += maple_keyb.o
 obj-$(CONFIG_KEYBOARD_BFIN)             += bf54x-keys.o
 obj-$(CONFIG_KEYBOARD_SH_KEYSC)         += sh_keysc.o
+obj-$(CONFIG_KEYBOARD_EP93XX)           += ep93xx_keypad.o
diff --git a/drivers/input/keyboard/ep93xx_keypad.c b/drivers/input/keyboard/ep93xx_keypad.c
new file mode 100644
index 000000000000..181d30e3018e
--- /dev/null
+++ b/drivers/input/keyboard/ep93xx_keypad.c
@@ -0,0 +1,470 @@
+/*
+ * Driver for the Cirrus EP93xx matrix keypad controller.
+ *
+ * Copyright (c) 2008 H Hartley Sweeten <hsweeten@visionengravers.com>
+ *
+ * Based on the pxa27x matrix keypad controller by Rodolfo Giometti.
+ *
+ * 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.
+ *
+ * NOTE:
+ *
+ * The 3-key reset is triggered by pressing the 3 keys in
+ * Row 0, Columns 2, 4, and 7 at the same time.  This action can
+ * be disabled by setting the EP93XX_KEYPAD_DISABLE_3_KEY flag.
+ *
+ * Normal operation for the matrix does not autorepeat the key press.
+ * This action can be enabled by setting the EP93XX_KEYPAD_AUTOREPEAT
+ * flag.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/clk.h>
+
+#include <mach/hardware.h>
+#include <mach/gpio.h>
+#include <mach/ep93xx_keypad.h>
+
+/*
+ * Keypad Interface Register offsets
+ */
+#define KEY_INIT                0x00    /* Key Scan Initialization register */
+#define KEY_DIAG                0x04    /* Key Scan Diagnostic register */
+#define KEY_REG                 0x08    /* Key Value Capture register */
+
+/* Key Scan Initialization Register bit defines */
+#define KEY_INIT_DBNC_MASK      (0x00ff0000)
+#define KEY_INIT_DBNC_SHIFT     (16)
+#define KEY_INIT_DIS3KY         (1<<15)
+#define KEY_INIT_DIAG           (1<<14)
+#define KEY_INIT_BACK           (1<<13)
+#define KEY_INIT_T2             (1<<12)
+#define KEY_INIT_PRSCL_MASK     (0x000003ff)
+#define KEY_INIT_PRSCL_SHIFT    (0)
+
+/* Key Scan Diagnostic Register bit defines */
+#define KEY_DIAG_MASK           (0x0000003f)
+#define KEY_DIAG_SHIFT          (0)
+
+/* Key Value Capture Register bit defines */
+#define KEY_REG_K               (1<<15)
+#define KEY_REG_INT             (1<<14)
+#define KEY_REG_2KEYS           (1<<13)
+#define KEY_REG_1KEY            (1<<12)
+#define KEY_REG_KEY2_MASK       (0x00000fc0)
+#define KEY_REG_KEY2_SHIFT      (6)
+#define KEY_REG_KEY1_MASK       (0x0000003f)
+#define KEY_REG_KEY1_SHIFT      (0)
+
+#define keypad_readl(off)       __raw_readl(keypad->mmio_base + (off))
+#define keypad_writel(v, off)   __raw_writel((v), keypad->mmio_base + (off))
+
+#define MAX_MATRIX_KEY_NUM      (MAX_MATRIX_KEY_ROWS * MAX_MATRIX_KEY_COLS)
+
+struct ep93xx_keypad {
+        struct ep93xx_keypad_platform_data *pdata;
+
+        struct clk *clk;
+        struct input_dev *input_dev;
+        void __iomem *mmio_base;
+
+        int irq;
+        int enabled;
+
+        int key1;
+        int key2;
+
+        unsigned int matrix_keycodes[MAX_MATRIX_KEY_NUM];
+};
+
+static void ep93xx_keypad_build_keycode(struct ep93xx_keypad *keypad)
+{
+        struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
+        struct input_dev *input_dev = keypad->input_dev;
+        int i;
+
+        for (i = 0; i < pdata->matrix_key_map_size; i++) {
+                unsigned int key = pdata->matrix_key_map[i];
+                int row = (key >> 28) & 0xf;
+                int col = (key >> 24) & 0xf;
+                int code = key & 0xffffff;
+
+                keypad->matrix_keycodes[(row << 3) + col] = code;
+                __set_bit(code, input_dev->keybit);
+        }
+}
+
+static irqreturn_t ep93xx_keypad_irq_handler(int irq, void *dev_id)
+{
+        struct ep93xx_keypad *keypad = dev_id;
+        struct input_dev *input_dev = keypad->input_dev;
+        unsigned int status = keypad_readl(KEY_REG);
+        int keycode, key1, key2;
+
+        keycode = (status & KEY_REG_KEY1_MASK) >> KEY_REG_KEY1_SHIFT;
+        key1 = keypad->matrix_keycodes[keycode];
+
+        keycode = (status & KEY_REG_KEY2_MASK) >> KEY_REG_KEY2_SHIFT;
+        key2 = keypad->matrix_keycodes[keycode];
+
+        if (status & KEY_REG_2KEYS) {
+                if (keypad->key1 && key1 != keypad->key1 && key2 != keypad->key1)
+                        input_report_key(input_dev, keypad->key1, 0);
+
+                if (keypad->key2 && key1 != keypad->key2 && key2 != keypad->key2)
+                        input_report_key(input_dev, keypad->key2, 0);
+
+                input_report_key(input_dev, key1, 1);
+                input_report_key(input_dev, key2, 1);
+
+                keypad->key1 = key1;
+                keypad->key2 = key2;
+
+        } else if (status & KEY_REG_1KEY) {
+                if (keypad->key1 && key1 != keypad->key1)
+                        input_report_key(input_dev, keypad->key1, 0);
+
+                if (keypad->key2 && key1 != keypad->key2)
+                        input_report_key(input_dev, keypad->key2, 0);
+
+                input_report_key(input_dev, key1, 1);
+
+                keypad->key1 = key1;
+                keypad->key2 = 0;
+
+        } else {
+                input_report_key(input_dev, keypad->key1, 0);
+                input_report_key(input_dev, keypad->key2, 0);
+
+                keypad->key1 = keypad->key2 = 0;
+        }
+        input_sync(input_dev);
+
+        return IRQ_HANDLED;
+}
+
+static void ep93xx_keypad_config(struct ep93xx_keypad *keypad)
+{
+        struct ep93xx_keypad_platform_data *pdata = keypad->pdata;
+        unsigned int val = 0;
+
+        clk_set_rate(keypad->clk, pdata->flags & EP93XX_KEYPAD_KDIV);
+
+        if (pdata->flags & EP93XX_KEYPAD_DISABLE_3_KEY)
+                val |= KEY_INIT_DIS3KY;
+        if (pdata->flags & EP93XX_KEYPAD_DIAG_MODE)
+                val |= KEY_INIT_DIAG;
+        if (pdata->flags & EP93XX_KEYPAD_BACK_DRIVE)
+                val |= KEY_INIT_BACK;
+        if (pdata->flags & EP93XX_KEYPAD_TEST_MODE)
+                val |= KEY_INIT_T2;
+
+        val |= ((pdata->debounce << KEY_INIT_DBNC_SHIFT) & KEY_INIT_DBNC_MASK);
+
+        val |= ((pdata->prescale << KEY_INIT_PRSCL_SHIFT) & KEY_INIT_PRSCL_MASK);
+
+        keypad_writel(val, KEY_INIT);
+}
+
+static int ep93xx_keypad_open(struct input_dev *pdev)
+{
+        struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
+
+        if (!keypad->enabled) {
+                ep93xx_keypad_config(keypad);
+                clk_enable(keypad->clk);
+                keypad->enabled = 1;
+        }
+
+        return 0;
+}
+
+static void ep93xx_keypad_close(struct input_dev *pdev)
+{
+        struct ep93xx_keypad *keypad = input_get_drvdata(pdev);
+
+        if (keypad->enabled) {
+                clk_disable(keypad->clk);
+                keypad->enabled = 0;
+        }
+}
+
+
+#ifdef CONFIG_PM
+/*
+ * NOTE: I don't know if this is correct, or will work on the ep93xx.
+ *
+ * None of the existing ep93xx drivers have power management support.
+ * But, this is basically what the pxa27x_keypad driver does.
+ */
+static int ep93xx_keypad_suspend(struct platform_device *pdev,
+                                 pm_message_t state)
+{
+        struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+        struct input_dev *input_dev = keypad->input_dev;
+
+        mutex_lock(&input_dev->mutex);
+
+        if (keypad->enabled) {
+                clk_disable(keypad->clk);
+                keypad->enabled = 0;
+        }
+
+        mutex_unlock(&input_dev->mutex);
+
+        if (device_may_wakeup(&pdev->dev))
+                enable_irq_wake(keypad->irq);
+
+        return 0;
+}
+
+static int ep93xx_keypad_resume(struct platform_device *pdev)
+{
+        struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+        struct input_dev *input_dev = keypad->input_dev;
+
+        if (device_may_wakeup(&pdev->dev))
+                disable_irq_wake(keypad->irq);
+
+        mutex_lock(&input_dev->mutex);
+
+        if (input_dev->users) {
+                if (!keypad->enabled) {
+                        ep93xx_keypad_config(keypad);
+                        clk_enable(keypad->clk);
+                        keypad->enabled = 1;
+                }
+        }
+
+        mutex_unlock(&input_dev->mutex);
+
+        return 0;
+}
+#else   /* !CONFIG_PM */
+#define ep93xx_keypad_suspend   NULL
+#define ep93xx_keypad_resume    NULL
+#endif  /* !CONFIG_PM */
+
+static int __devinit ep93xx_keypad_probe(struct platform_device *pdev)
+{
+        struct ep93xx_keypad *keypad;
+        struct ep93xx_keypad_platform_data *pdata = pdev->dev.platform_data;
+        struct input_dev *input_dev;
+        struct resource *res;
+        int irq, err, i, gpio;
+
+        if (!pdata ||
+            !pdata->matrix_key_rows ||
+            pdata->matrix_key_rows > MAX_MATRIX_KEY_ROWS ||
+            !pdata->matrix_key_cols ||
+            pdata->matrix_key_cols > MAX_MATRIX_KEY_COLS) {
+                dev_err(&pdev->dev, "invalid or missing platform data\n");
+                return -EINVAL;
+        }
+
+        keypad = kzalloc(sizeof(struct ep93xx_keypad), GFP_KERNEL);
+        if (!keypad) {
+                dev_err(&pdev->dev, "failed to allocate driver data\n");
+                return -ENOMEM;
+        }
+
+        keypad->pdata = pdata;
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0) {
+                dev_err(&pdev->dev, "failed to get keypad irq\n");
+                err = -ENXIO;
+                goto failed_free;
+        }
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res) {
+                dev_err(&pdev->dev, "failed to get I/O memory\n");
+                err = -ENXIO;
+                goto failed_free;
+        }
+
+        res = request_mem_region(res->start, resource_size(res), pdev->name);
+        if (!res) {
+                dev_err(&pdev->dev, "failed to request I/O memory\n");
+                err = -EBUSY;
+                goto failed_free;
+        }
+
+        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");
+                err = -ENXIO;
+                goto failed_free_mem;
+        }
+
+        /* Request the needed GPIO's */
+        gpio = EP93XX_GPIO_LINE_ROW0;
+        for (i = 0; i < keypad->pdata->matrix_key_rows; i++, gpio++) {
+                err = gpio_request(gpio, pdev->name);
+                if (err) {
+                        dev_err(&pdev->dev, "failed to request gpio-%d\n",
+                                gpio);
+                        goto failed_free_rows;
+                }
+        }
+
+        gpio = EP93XX_GPIO_LINE_COL0;
+        for (i = 0; i < keypad->pdata->matrix_key_cols; i++, gpio++) {
+                err = gpio_request(gpio, pdev->name);
+                if (err) {
+                        dev_err(&pdev->dev, "failed to request gpio-%d\n",
+                                gpio);
+                        goto failed_free_cols;
+                }
+        }
+
+        keypad->clk = clk_get(&pdev->dev, "key_clk");
+        if (IS_ERR(keypad->clk)) {
+                dev_err(&pdev->dev, "failed to get keypad clock\n");
+                err = PTR_ERR(keypad->clk);
+                goto failed_free_io;
+        }
+
+        /* Create and register the input driver */
+        input_dev = input_allocate_device();
+        if (!input_dev) {
+                dev_err(&pdev->dev, "failed to allocate input device\n");
+                err = -ENOMEM;
+                goto failed_put_clk;
+        }
+
+        keypad->input_dev = input_dev;
+
+        input_dev->name = pdev->name;
+        input_dev->id.bustype = BUS_HOST;
+        input_dev->open = ep93xx_keypad_open;
+        input_dev->close = ep93xx_keypad_close;
+        input_dev->dev.parent = &pdev->dev;
+        input_dev->keycode = keypad->matrix_keycodes;
+        input_dev->keycodesize = sizeof(keypad->matrix_keycodes[0]);
+        input_dev->keycodemax = ARRAY_SIZE(keypad->matrix_keycodes);
+
+        input_set_drvdata(input_dev, keypad);
+
+        input_dev->evbit[0] = BIT_MASK(EV_KEY);
+        if (keypad->pdata->flags & EP93XX_KEYPAD_AUTOREPEAT)
+                input_dev->evbit[0] |= BIT_MASK(EV_REP);
+
+        ep93xx_keypad_build_keycode(keypad);
+        platform_set_drvdata(pdev, keypad);
+
+        err = request_irq(irq, ep93xx_keypad_irq_handler, IRQF_DISABLED,
+                                pdev->name, keypad);
+        if (err) {
+                dev_err(&pdev->dev, "failed to request IRQ\n");
+                goto failed_free_dev;
+        }
+
+        keypad->irq = irq;
+
+        /* Register the input device */
+        err = input_register_device(input_dev);
+        if (err) {
+                dev_err(&pdev->dev, "failed to register input device\n");
+                goto failed_free_irq;
+        }
+
+        device_init_wakeup(&pdev->dev, 1);
+
+        return 0;
+
+failed_free_irq:
+        free_irq(irq, pdev);
+        platform_set_drvdata(pdev, NULL);
+failed_free_dev:
+        input_free_device(input_dev);
+failed_put_clk:
+        clk_put(keypad->clk);
+failed_free_io:
+        i = keypad->pdata->matrix_key_cols - 1;
+        gpio = EP93XX_GPIO_LINE_COL0 + i;
+failed_free_cols:
+        for ( ; i >= 0; i--, gpio--)
+                gpio_free(gpio);
+        i = keypad->pdata->matrix_key_rows - 1;
+        gpio = EP93XX_GPIO_LINE_ROW0 + i;
+failed_free_rows:
+        for ( ; i >= 0; i--, gpio--)
+                gpio_free(gpio);
+        iounmap(keypad->mmio_base);
+failed_free_mem:
+        release_mem_region(res->start, resource_size(res));
+failed_free:
+        kfree(keypad);
+        return err;
+}
+
+static int __devexit ep93xx_keypad_remove(struct platform_device *pdev)
+{
+        struct ep93xx_keypad *keypad = platform_get_drvdata(pdev);
+        struct resource *res;
+        int i, gpio;
+
+        free_irq(keypad->irq, pdev);
+
+        platform_set_drvdata(pdev, NULL);
+
+        if (keypad->enabled)
+                clk_disable(keypad->clk);
+        clk_put(keypad->clk);
+
+        input_unregister_device(keypad->input_dev);
+
+        i = keypad->pdata->matrix_key_cols - 1;
+        gpio = EP93XX_GPIO_LINE_COL0 + i;
+        for ( ; i >= 0; i--, gpio--)
+                gpio_free(gpio);
+
+        i = keypad->pdata->matrix_key_rows - 1;
+        gpio = EP93XX_GPIO_LINE_ROW0 + i;
+        for ( ; i >= 0; i--, gpio--)
+                gpio_free(gpio);
+
+        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 ep93xx_keypad_driver = {
+        .driver         = {
+                .name   = "ep93xx-keypad",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = ep93xx_keypad_probe,
+        .remove         = __devexit_p(ep93xx_keypad_remove),
+        .suspend        = ep93xx_keypad_suspend,
+        .resume         = ep93xx_keypad_resume,
+};
+
+static int __init ep93xx_keypad_init(void)
+{
+        return platform_driver_register(&ep93xx_keypad_driver);
+}
+
+static void __exit ep93xx_keypad_exit(void)
+{
+        platform_driver_unregister(&ep93xx_keypad_driver);
+}
+
+module_init(ep93xx_keypad_init);
+module_exit(ep93xx_keypad_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
+MODULE_DESCRIPTION("EP93xx Matrix Keypad Controller");
+MODULE_ALIAS("platform:ep93xx-keypad");