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>");