input: Add STMPE keypad driver

Add an input driver for the keypad on STMPE I/O expanders.  This driver
uses the common support provided by the STMPE MFD driver.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 397 insertions, 0 deletions

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index b171f63fe4d7..9cc488d21490 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -395,6 +395,16 @@ config KEYBOARD_SH_KEYSC
           To compile this driver as a module, choose M here: the
           module will be called sh_keysc.
 
+config KEYBOARD_STMPE
+        tristate "STMPE keypad support"
+        depends on MFD_STMPE
+        help
+          Say Y here if you want to use the keypad controller on STMPE I/O
+          expanders.
+
+          To compile this driver as a module, choose M here: the module will be
+          called stmpe-keypad.
+
 config KEYBOARD_DAVINCI
         tristate "TI DaVinci Key Scan"
         depends on ARCH_DAVINCI_DM365
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 1a66d5f1ca8b..504b591be0cd 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_KEYBOARD_PXA930_ROTARY)	+= pxa930_rotary.o
 obj-$(CONFIG_KEYBOARD_QT2160)           += qt2160.o
 obj-$(CONFIG_KEYBOARD_SAMSUNG)          += samsung-keypad.o
 obj-$(CONFIG_KEYBOARD_SH_KEYSC)         += sh_keysc.o
+obj-$(CONFIG_KEYBOARD_STMPE)            += stmpe-keypad.o
 obj-$(CONFIG_KEYBOARD_STOWAWAY)         += stowaway.o
 obj-$(CONFIG_KEYBOARD_SUNKBD)           += sunkbd.o
 obj-$(CONFIG_KEYBOARD_TWL4030)          += twl4030_keypad.o
diff --git a/drivers/input/keyboard/stmpe-keypad.c b/drivers/input/keyboard/stmpe-keypad.c
new file mode 100644
index 000000000000..ab7610ca10eb
--- /dev/null
+++ b/drivers/input/keyboard/stmpe-keypad.c
@@ -0,0 +1,386 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010
+ *
+ * License Terms: GNU General Public License, version 2
+ * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/input/matrix_keypad.h>
+#include <linux/mfd/stmpe.h>
+
+/* These are at the same addresses in all STMPE variants */
+#define STMPE_KPC_COL                   0x60
+#define STMPE_KPC_ROW_MSB               0x61
+#define STMPE_KPC_ROW_LSB               0x62
+#define STMPE_KPC_CTRL_MSB              0x63
+#define STMPE_KPC_CTRL_LSB              0x64
+#define STMPE_KPC_COMBI_KEY_0           0x65
+#define STMPE_KPC_COMBI_KEY_1           0x66
+#define STMPE_KPC_COMBI_KEY_2           0x67
+#define STMPE_KPC_DATA_BYTE0            0x68
+#define STMPE_KPC_DATA_BYTE1            0x69
+#define STMPE_KPC_DATA_BYTE2            0x6a
+#define STMPE_KPC_DATA_BYTE3            0x6b
+#define STMPE_KPC_DATA_BYTE4            0x6c
+
+#define STMPE_KPC_CTRL_LSB_SCAN         (0x1 << 0)
+#define STMPE_KPC_CTRL_LSB_DEBOUNCE     (0x7f << 1)
+#define STMPE_KPC_CTRL_MSB_SCAN_COUNT   (0xf << 4)
+
+#define STMPE_KPC_ROW_MSB_ROWS          0xff
+
+#define STMPE_KPC_DATA_UP               (0x1 << 7)
+#define STMPE_KPC_DATA_ROW              (0xf << 3)
+#define STMPE_KPC_DATA_COL              (0x7 << 0)
+#define STMPE_KPC_DATA_NOKEY_MASK       0x78
+
+#define STMPE_KEYPAD_MAX_DEBOUNCE       127
+#define STMPE_KEYPAD_MAX_SCAN_COUNT     15
+
+#define STMPE_KEYPAD_MAX_ROWS           8
+#define STMPE_KEYPAD_MAX_COLS           8
+#define STMPE_KEYPAD_ROW_SHIFT          3
+#define STMPE_KEYPAD_KEYMAP_SIZE        \
+        (STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
+
+/**
+ * struct stmpe_keypad_variant - model-specific attributes
+ * @auto_increment: whether the KPC_DATA_BYTE register address
+ *                  auto-increments on multiple read
+ * @num_data: number of data bytes
+ * @num_normal_data: number of normal keys' data bytes
+ * @max_cols: maximum number of columns supported
+ * @max_rows: maximum number of rows supported
+ * @col_gpios: bitmask of gpios which can be used for columns
+ * @row_gpios: bitmask of gpios which can be used for rows
+ */
+struct stmpe_keypad_variant {
+        bool            auto_increment;
+        int             num_data;
+        int             num_normal_data;
+        int             max_cols;
+        int             max_rows;
+        unsigned int    col_gpios;
+        unsigned int    row_gpios;
+};
+
+static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
+        [STMPE1601] = {
+                .auto_increment         = true,
+                .num_data               = 5,
+                .num_normal_data        = 3,
+                .max_cols               = 8,
+                .max_rows               = 8,
+                .col_gpios              = 0x000ff,      /* GPIO 0 - 7 */
+                .row_gpios              = 0x0ff00,      /* GPIO 8 - 15 */
+        },
+        [STMPE2401] = {
+                .auto_increment         = false,
+                .num_data               = 3,
+                .num_normal_data        = 2,
+                .max_cols               = 8,
+                .max_rows               = 12,
+                .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
+                .row_gpios              = 0x1fef00,     /* GPIO 8-14, 16-20 */
+        },
+        [STMPE2403] = {
+                .auto_increment         = true,
+                .num_data               = 5,
+                .num_normal_data        = 3,
+                .max_cols               = 8,
+                .max_rows               = 12,
+                .col_gpios              = 0x0000ff,     /* GPIO 0 - 7*/
+                .row_gpios              = 0x1fef00,     /* GPIO 8-14, 16-20 */
+        },
+};
+
+struct stmpe_keypad {
+        struct stmpe *stmpe;
+        struct input_dev *input;
+        const struct stmpe_keypad_variant *variant;
+        const struct stmpe_keypad_platform_data *plat;
+
+        unsigned int rows;
+        unsigned int cols;
+
+        unsigned short keymap[STMPE_KEYPAD_KEYMAP_SIZE];
+};
+
+static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
+{
+        const struct stmpe_keypad_variant *variant = keypad->variant;
+        struct stmpe *stmpe = keypad->stmpe;
+        int ret;
+        int i;
+
+        if (variant->auto_increment)
+                return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
+                                        variant->num_data, data);
+
+        for (i = 0; i < variant->num_data; i++) {
+                ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
+                if (ret < 0)
+                        return ret;
+
+                data[i] = ret;
+        }
+
+        return 0;
+}
+
+static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
+{
+        struct stmpe_keypad *keypad = dev;
+        struct input_dev *input = keypad->input;
+        const struct stmpe_keypad_variant *variant = keypad->variant;
+        u8 fifo[variant->num_data];
+        int ret;
+        int i;
+
+        ret = stmpe_keypad_read_data(keypad, fifo);
+        if (ret < 0)
+                return IRQ_NONE;
+
+        for (i = 0; i < variant->num_normal_data; i++) {
+                u8 data = fifo[i];
+                int row = (data & STMPE_KPC_DATA_ROW) >> 3;
+                int col = data & STMPE_KPC_DATA_COL;
+                int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
+                bool up = data & STMPE_KPC_DATA_UP;
+
+                if ((data & STMPE_KPC_DATA_NOKEY_MASK)
+                        == STMPE_KPC_DATA_NOKEY_MASK)
+                        continue;
+
+                input_event(input, EV_MSC, MSC_SCAN, code);
+                input_report_key(input, keypad->keymap[code], !up);
+                input_sync(input);
+        }
+
+        return IRQ_HANDLED;
+}
+
+static int __devinit stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
+{
+        const struct stmpe_keypad_variant *variant = keypad->variant;
+        unsigned int col_gpios = variant->col_gpios;
+        unsigned int row_gpios = variant->row_gpios;
+        struct stmpe *stmpe = keypad->stmpe;
+        unsigned int pins = 0;
+        int i;
+
+        /*
+         * Figure out which pins need to be set to the keypad alternate
+         * function.
+         *
+         * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
+         * for the keypad.
+         *
+         * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
+         * for the keypad) are used on the board.
+         */
+
+        for (i = 0; i < variant->max_cols; i++) {
+                int num = __ffs(col_gpios);
+
+                if (keypad->cols & (1 << i))
+                        pins |= 1 << num;
+
+                col_gpios &= ~(1 << num);
+        }
+
+        for (i = 0; i < variant->max_rows; i++) {
+                int num = __ffs(row_gpios);
+
+                if (keypad->rows & (1 << i))
+                        pins |= 1 << num;
+
+                row_gpios &= ~(1 << num);
+        }
+
+        return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
+}
+
+static int __devinit stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
+{
+        const struct stmpe_keypad_platform_data *plat = keypad->plat;
+        const struct stmpe_keypad_variant *variant = keypad->variant;
+        struct stmpe *stmpe = keypad->stmpe;
+        int ret;
+
+        if (plat->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
+                return -EINVAL;
+
+        if (plat->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
+                return -EINVAL;
+
+        ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
+        if (ret < 0)
+                return ret;
+
+        ret = stmpe_keypad_altfunc_init(keypad);
+        if (ret < 0)
+                return ret;
+
+        ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
+        if (ret < 0)
+                return ret;
+
+        ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
+        if (ret < 0)
+                return ret;
+
+        if (variant->max_rows > 8) {
+                ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
+                                     STMPE_KPC_ROW_MSB_ROWS,
+                                     keypad->rows >> 8);
+                if (ret < 0)
+                        return ret;
+        }
+
+        ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
+                             STMPE_KPC_CTRL_MSB_SCAN_COUNT,
+                             plat->scan_count << 4);
+        if (ret < 0)
+                return ret;
+
+        return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
+                              STMPE_KPC_CTRL_LSB_SCAN |
+                              STMPE_KPC_CTRL_LSB_DEBOUNCE,
+                              STMPE_KPC_CTRL_LSB_SCAN |
+                              (plat->debounce_ms << 1));
+}
+
+static int __devinit stmpe_keypad_probe(struct platform_device *pdev)
+{
+        struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
+        struct stmpe_keypad_platform_data *plat;
+        struct stmpe_keypad *keypad;
+        struct input_dev *input;
+        int ret;
+        int irq;
+        int i;
+
+        plat = stmpe->pdata->keypad;
+        if (!plat)
+                return -ENODEV;
+
+        irq = platform_get_irq(pdev, 0);
+        if (irq < 0)
+                return irq;
+
+        keypad = kzalloc(sizeof(struct stmpe_keypad), GFP_KERNEL);
+        if (!keypad)
+                return -ENOMEM;
+
+        input = input_allocate_device();
+        if (!input) {
+                ret = -ENOMEM;
+                goto out_freekeypad;
+        }
+
+        input->name = "STMPE keypad";
+        input->id.bustype = BUS_I2C;
+        input->dev.parent = &pdev->dev;
+
+        input_set_capability(input, EV_MSC, MSC_SCAN);
+
+        __set_bit(EV_KEY, input->evbit);
+        if (!plat->no_autorepeat)
+                __set_bit(EV_REP, input->evbit);
+
+        input->keycode = keypad->keymap;
+        input->keycodesize = sizeof(keypad->keymap[0]);
+        input->keycodemax = ARRAY_SIZE(keypad->keymap);
+
+        matrix_keypad_build_keymap(plat->keymap_data, STMPE_KEYPAD_ROW_SHIFT,
+                                   input->keycode, input->keybit);
+
+        for (i = 0; i < plat->keymap_data->keymap_size; i++) {
+                unsigned int key = plat->keymap_data->keymap[i];
+
+                keypad->cols |= 1 << KEY_COL(key);
+                keypad->rows |= 1 << KEY_ROW(key);
+        }
+
+        keypad->stmpe = stmpe;
+        keypad->plat = plat;
+        keypad->input = input;
+        keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
+
+        ret = stmpe_keypad_chip_init(keypad);
+        if (ret < 0)
+                goto out_freeinput;
+
+        ret = input_register_device(input);
+        if (ret) {
+                dev_err(&pdev->dev,
+                        "unable to register input device: %d\n", ret);
+                goto out_freeinput;
+        }
+
+        ret = request_threaded_irq(irq, NULL, stmpe_keypad_irq, IRQF_ONESHOT,
+                                   "stmpe-keypad", keypad);
+        if (ret) {
+                dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
+                goto out_unregisterinput;
+        }
+
+        platform_set_drvdata(pdev, keypad);
+
+        return 0;
+
+out_unregisterinput:
+        input_unregister_device(input);
+        input = NULL;
+out_freeinput:
+        input_free_device(input);
+out_freekeypad:
+        kfree(keypad);
+        return ret;
+}
+
+static int __devexit stmpe_keypad_remove(struct platform_device *pdev)
+{
+        struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
+        struct stmpe *stmpe = keypad->stmpe;
+        int irq = platform_get_irq(pdev, 0);
+
+        stmpe_disable(stmpe, STMPE_BLOCK_KEYPAD);
+
+        free_irq(irq, keypad);
+        input_unregister_device(keypad->input);
+        platform_set_drvdata(pdev, NULL);
+        kfree(keypad);
+
+        return 0;
+}
+
+static struct platform_driver stmpe_keypad_driver = {
+        .driver.name    = "stmpe-keypad",
+        .driver.owner   = THIS_MODULE,
+        .probe          = stmpe_keypad_probe,
+        .remove         = __devexit_p(stmpe_keypad_remove),
+};
+
+static int __init stmpe_keypad_init(void)
+{
+        return platform_driver_register(&stmpe_keypad_driver);
+}
+module_init(stmpe_keypad_init);
+
+static void __exit stmpe_keypad_exit(void)
+{
+        platform_driver_unregister(&stmpe_keypad_driver);
+}
+module_exit(stmpe_keypad_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("STMPExxxx keypad driver");
+MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");