[deliverable/linux.git] / drivers / input / keyboard / twl4030_keypad.c

/*
 * twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
 *
 * Copyright (C) 2007 Texas Instruments, Inc.
 * Copyright (C) 2008 Nokia Corporation
 *
 * Code re-written for 2430SDP by:
 * Syed Mohammed Khasim <x0khasim@ti.com>
 *
 * Initial Code:
 * Manjunatha G K <manjugk@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/platform_device.h>
#include <linux/i2c/twl.h>
#include <linux/slab.h>
#include <linux/of.h>

/*
 * The TWL4030 family chips include a keypad controller that supports
 * up to an 8x8 switch matrix.  The controller can issue system wakeup
 * events, since it uses only the always-on 32KiHz oscillator, and has
 * an internal state machine that decodes pressed keys, including
 * multi-key combinations.
 *
 * This driver lets boards define what keycodes they wish to report for
 * which scancodes, as part of the "struct twl4030_keypad_data" used in
 * the probe() routine.
 *
 * See the TPS65950 documentation; that's the general availability
 * version of the TWL5030 second generation part.
 */
#define TWL4030_MAX_ROWS	8	/* TWL4030 hard limit */
#define TWL4030_MAX_COLS	8
/*
 * Note that we add space for an extra column so that we can handle
 * row lines connected to the gnd (see twl4030_col_xlate()).
 */
#define TWL4030_ROW_SHIFT	4
#define TWL4030_KEYMAP_SIZE	(TWL4030_MAX_ROWS << TWL4030_ROW_SHIFT)

struct twl4030_keypad {
	unsigned short	keymap[TWL4030_KEYMAP_SIZE];
	u16		kp_state[TWL4030_MAX_ROWS];
	bool		autorepeat;
	unsigned	n_rows;
	unsigned	n_cols;
	unsigned	irq;

	struct device *dbg_dev;
	struct input_dev *input;
};

/*----------------------------------------------------------------------*/

/* arbitrary prescaler value 0..7 */
#define PTV_PRESCALER			4

/* Register Offsets */
#define KEYP_CTRL			0x00
#define KEYP_DEB			0x01
#define KEYP_LONG_KEY			0x02
#define KEYP_LK_PTV			0x03
#define KEYP_TIMEOUT_L			0x04
#define KEYP_TIMEOUT_H			0x05
#define KEYP_KBC			0x06
#define KEYP_KBR			0x07
#define KEYP_SMS			0x08
#define KEYP_FULL_CODE_7_0		0x09	/* row 0 column status */
#define KEYP_FULL_CODE_15_8		0x0a	/* ... row 1 ... */
#define KEYP_FULL_CODE_23_16		0x0b
#define KEYP_FULL_CODE_31_24		0x0c
#define KEYP_FULL_CODE_39_32		0x0d
#define KEYP_FULL_CODE_47_40		0x0e
#define KEYP_FULL_CODE_55_48		0x0f
#define KEYP_FULL_CODE_63_56		0x10
#define KEYP_ISR1			0x11
#define KEYP_IMR1			0x12
#define KEYP_ISR2			0x13
#define KEYP_IMR2			0x14
#define KEYP_SIR			0x15
#define KEYP_EDR			0x16	/* edge triggers */
#define KEYP_SIH_CTRL			0x17

/* KEYP_CTRL_REG Fields */
#define KEYP_CTRL_SOFT_NRST		BIT(0)
#define KEYP_CTRL_SOFTMODEN		BIT(1)
#define KEYP_CTRL_LK_EN			BIT(2)
#define KEYP_CTRL_TOE_EN		BIT(3)
#define KEYP_CTRL_TOLE_EN		BIT(4)
#define KEYP_CTRL_RP_EN			BIT(5)
#define KEYP_CTRL_KBD_ON		BIT(6)

/* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
#define KEYP_PERIOD_US(t, prescale)	((t) / (31 << (prescale + 1)) - 1)

/* KEYP_LK_PTV_REG Fields */
#define KEYP_LK_PTV_PTV_SHIFT		5

/* KEYP_{IMR,ISR,SIR} Fields */
#define KEYP_IMR1_MIS			BIT(3)
#define KEYP_IMR1_TO			BIT(2)
#define KEYP_IMR1_LK			BIT(1)
#define KEYP_IMR1_KP			BIT(0)

/* KEYP_EDR Fields */
#define KEYP_EDR_KP_FALLING		0x01
#define KEYP_EDR_KP_RISING		0x02
#define KEYP_EDR_KP_BOTH		0x03
#define KEYP_EDR_LK_FALLING		0x04
#define KEYP_EDR_LK_RISING		0x08
#define KEYP_EDR_TO_FALLING		0x10
#define KEYP_EDR_TO_RISING		0x20
#define KEYP_EDR_MIS_FALLING		0x40
#define KEYP_EDR_MIS_RISING		0x80


/*----------------------------------------------------------------------*/

static int twl4030_kpread(struct twl4030_keypad *kp,
		u8 *data, u32 reg, u8 num_bytes)
{
	int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);

	if (ret < 0)
		dev_warn(kp->dbg_dev,
			"Couldn't read TWL4030: %X - ret %d[%x]\n",
			 reg, ret, ret);

	return ret;
}

static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
{
	int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);

	if (ret < 0)
		dev_warn(kp->dbg_dev,
			"Could not write TWL4030: %X - ret %d[%x]\n",
			 reg, ret, ret);

	return ret;
}

static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
{
	/* If all bits in a row are active for all coloumns then
	 * we have that row line connected to gnd. Mark this
	 * key on as if it was on matrix position n_cols (ie
	 * one higher than the size of the matrix).
	 */
	if (col == 0xFF)
		return 1 << kp->n_cols;
	else
		return col & ((1 << kp->n_cols) - 1);
}

static int twl4030_read_kp_matrix_state(struct twl4030_keypad *kp, u16 *state)
{
	u8 new_state[TWL4030_MAX_ROWS];
	int row;
	int ret = twl4030_kpread(kp, new_state,
				 KEYP_FULL_CODE_7_0, kp->n_rows);
	if (ret >= 0)
		for (row = 0; row < kp->n_rows; row++)
			state[row] = twl4030_col_xlate(kp, new_state[row]);

	return ret;
}

static bool twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state)
{
	int i;
	u16 check = 0;

	for (i = 0; i < kp->n_rows; i++) {
		u16 col = key_state[i];

		if ((col & check) && hweight16(col) > 1)
			return true;

		check |= col;
	}

	return false;
}

static void twl4030_kp_scan(struct twl4030_keypad *kp, bool release_all)
{
	struct input_dev *input = kp->input;
	u16 new_state[TWL4030_MAX_ROWS];
	int col, row;

	if (release_all)
		memset(new_state, 0, sizeof(new_state));
	else {
		/* check for any changes */
		int ret = twl4030_read_kp_matrix_state(kp, new_state);

		if (ret < 0)	/* panic ... */
			return;

		if (twl4030_is_in_ghost_state(kp, new_state))
			return;
	}

	/* check for changes and print those */
	for (row = 0; row < kp->n_rows; row++) {
		int changed = new_state[row] ^ kp->kp_state[row];

		if (!changed)
			continue;

		/* Extra column handles "all gnd" rows */
		for (col = 0; col < kp->n_cols + 1; col++) {
			int code;

			if (!(changed & (1 << col)))
				continue;

			dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
				(new_state[row] & (1 << col)) ?
				"press" : "release");

			code = MATRIX_SCAN_CODE(row, col, TWL4030_ROW_SHIFT);
			input_event(input, EV_MSC, MSC_SCAN, code);
			input_report_key(input, kp->keymap[code],
					 new_state[row] & (1 << col));
		}
		kp->kp_state[row] = new_state[row];
	}
	input_sync(input);
}

/*
 * Keypad interrupt handler
 */
static irqreturn_t do_kp_irq(int irq, void *_kp)
{
	struct twl4030_keypad *kp = _kp;
	u8 reg;
	int ret;

	/* Read & Clear TWL4030 pending interrupt */
	ret = twl4030_kpread(kp, &reg, KEYP_ISR1, 1);

	/* Release all keys if I2C has gone bad or
	 * the KEYP has gone to idle state */
	if (ret >= 0 && (reg & KEYP_IMR1_KP))
		twl4030_kp_scan(kp, false);
	else
		twl4030_kp_scan(kp, true);

	return IRQ_HANDLED;
}

static int twl4030_kp_program(struct twl4030_keypad *kp)
{
	u8 reg;
	int i;

	/* Enable controller, with hardware decoding but not autorepeat */
	reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
		| KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
	if (twl4030_kpwrite_u8(kp, reg, KEYP_CTRL) < 0)
		return -EIO;

	/* NOTE:  we could use sih_setup() here to package keypad
	 * event sources as four different IRQs ... but we don't.
	 */

	/* Enable TO rising and KP rising and falling edge detection */
	reg = KEYP_EDR_KP_BOTH | KEYP_EDR_TO_RISING;
	if (twl4030_kpwrite_u8(kp, reg, KEYP_EDR) < 0)
		return -EIO;

	/* Set PTV prescaler Field */
	reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
	if (twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV) < 0)
		return -EIO;

	/* Set key debounce time to 20 ms */
	i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
	if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
		return -EIO;

	/* Set timeout period to 200 ms */
	i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
	if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
		return -EIO;

	if (twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H) < 0)
		return -EIO;

	/*
	 * Enable Clear-on-Read; disable remembering events that fire
	 * after the IRQ but before our handler acks (reads) them,
	 */
	reg = TWL4030_SIH_CTRL_COR_MASK | TWL4030_SIH_CTRL_PENDDIS_MASK;
	if (twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL) < 0)
		return -EIO;

	/* initialize key state; irqs update it from here on */
	if (twl4030_read_kp_matrix_state(kp, kp->kp_state) < 0)
		return -EIO;

	return 0;
}

/*
 * Registers keypad device with input subsystem
 * and configures TWL4030 keypad registers
 */
static int twl4030_kp_probe(struct platform_device *pdev)
{
	struct twl4030_keypad_data *pdata = dev_get_platdata(&pdev->dev);
	const struct matrix_keymap_data *keymap_data = NULL;
	struct twl4030_keypad *kp;
	struct input_dev *input;
	u8 reg;
	int error;

	kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL);
	if (!kp)
		return -ENOMEM;

	input = devm_input_allocate_device(&pdev->dev);
	if (!input)
		return -ENOMEM;

	/* get the debug device */
	kp->dbg_dev		= &pdev->dev;
	kp->input		= input;

	/* setup input device */
	input->name		= "TWL4030 Keypad";
	input->phys		= "twl4030_keypad/input0";

	input->id.bustype	= BUS_HOST;
	input->id.vendor	= 0x0001;
	input->id.product	= 0x0001;
	input->id.version	= 0x0003;

	if (pdata) {
		if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
			dev_err(&pdev->dev, "Missing platform_data\n");
			return -EINVAL;
		}

		kp->n_rows = pdata->rows;
		kp->n_cols = pdata->cols;
		kp->autorepeat = pdata->rep;
		keymap_data = pdata->keymap_data;
	} else {
		error = matrix_keypad_parse_of_params(&pdev->dev, &kp->n_rows,
						      &kp->n_cols);
		if (error)
			return error;

		kp->autorepeat = true;
	}

	if (kp->n_rows > TWL4030_MAX_ROWS || kp->n_cols > TWL4030_MAX_COLS) {
		dev_err(&pdev->dev,
			"Invalid rows/cols amount specified in platform/devicetree data\n");
		return -EINVAL;
	}

	kp->irq = platform_get_irq(pdev, 0);
	if (!kp->irq) {
		dev_err(&pdev->dev, "no keyboard irq assigned\n");
		return -EINVAL;
	}

	error = matrix_keypad_build_keymap(keymap_data, NULL,
					   TWL4030_MAX_ROWS,
					   1 << TWL4030_ROW_SHIFT,
					   kp->keymap, input);
	if (error) {
		dev_err(kp->dbg_dev, "Failed to build keymap\n");
		return error;
	}

	input_set_capability(input, EV_MSC, MSC_SCAN);
	/* Enable auto repeat feature of Linux input subsystem */
	if (kp->autorepeat)
		__set_bit(EV_REP, input->evbit);

	error = input_register_device(input);
	if (error) {
		dev_err(kp->dbg_dev,
			"Unable to register twl4030 keypad device\n");
		return error;
	}

	error = twl4030_kp_program(kp);
	if (error)
		return error;

	/*
	 * This ISR will always execute in kernel thread context because of
	 * the need to access the TWL4030 over the I2C bus.
	 *
	 * NOTE:  we assume this host is wired to TWL4040 INT1, not INT2 ...
	 */
	error = devm_request_threaded_irq(&pdev->dev, kp->irq, NULL, do_kp_irq,
					  0, pdev->name, kp);
	if (error) {
		dev_info(kp->dbg_dev, "request_irq failed for irq no=%d: %d\n",
			kp->irq, error);
		return error;
	}

	/* Enable KP and TO interrupts now. */
	reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
	if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) {
		/* mask all events - we don't care about the result */
		(void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
		return -EIO;
	}

	platform_set_drvdata(pdev, kp);
	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id twl4030_keypad_dt_match_table[] = {
	{ .compatible = "ti,twl4030-keypad" },
	{},
};
MODULE_DEVICE_TABLE(of, twl4030_keypad_dt_match_table);
#endif

/*
 * NOTE: twl4030 are multi-function devices connected via I2C.
 * So this device is a child of an I2C parent, thus it needs to
 * support unplug/replug (which most platform devices don't).
 */

static struct platform_driver twl4030_kp_driver = {
	.probe		= twl4030_kp_probe,
	.driver		= {
		.name	= "twl4030_keypad",
		.of_match_table = of_match_ptr(twl4030_keypad_dt_match_table),
	},
};
module_platform_driver(twl4030_kp_driver);

MODULE_AUTHOR("Texas Instruments");
MODULE_DESCRIPTION("TWL4030 Keypad Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:twl4030_keypad");
Commit	Line	Data
9d834068 DB	1	/*
	2	* twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
	3	*
	4	* Copyright (C) 2007 Texas Instruments, Inc.
	5	* Copyright (C) 2008 Nokia Corporation
	6	*
	7	* Code re-written for 2430SDP by:
	8	* Syed Mohammed Khasim <x0khasim@ti.com>
	9	*
	10	* Initial Code:
	11	* Manjunatha G K <manjugk@ti.com>
	12	*
	13	* This program is free software; you can redistribute it and/or modify
	14	* it under the terms of the GNU General Public License as published by
	15	* the Free Software Foundation; either version 2 of the License, or
	16	* (at your option) any later version.
	17	*
	18	* This program is distributed in the hope that it will be useful,
	19	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	20	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	21	* GNU General Public License for more details.
	22	*
	23	* You should have received a copy of the GNU General Public License
	24	* along with this program; if not, write to the Free Software
	25	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	26	*/
	27
	28	#include <linux/kernel.h>
	29	#include <linux/module.h>
9d834068 DB	30	#include <linux/interrupt.h>
	31	#include <linux/input.h>
	32	#include <linux/platform_device.h>
b07682b6	33	#include <linux/i2c/twl.h>
5a0e3ad6	34	#include <linux/slab.h>
7abf38d6	35	#include <linux/of.h>
9d834068	36
9d834068 DB	37	/*
	38	* The TWL4030 family chips include a keypad controller that supports
	39	* up to an 8x8 switch matrix. The controller can issue system wakeup
	40	* events, since it uses only the always-on 32KiHz oscillator, and has
	41	* an internal state machine that decodes pressed keys, including
	42	* multi-key combinations.
	43	*
	44	* This driver lets boards define what keycodes they wish to report for
	45	* which scancodes, as part of the "struct twl4030_keypad_data" used in
	46	* the probe() routine.
	47	*
	48	* See the TPS65950 documentation; that's the general availability
	49	* version of the TWL5030 second generation part.
	50	*/
	51	#define TWL4030_MAX_ROWS 8 /* TWL4030 hard limit */
	52	#define TWL4030_MAX_COLS 8
3fea6026 DT	53	/*
	54	* Note that we add space for an extra column so that we can handle
	55	* row lines connected to the gnd (see twl4030_col_xlate()).
	56	*/
	57	#define TWL4030_ROW_SHIFT 4
	58	#define TWL4030_KEYMAP_SIZE (TWL4030_MAX_ROWS << TWL4030_ROW_SHIFT)
9d834068 DB	59
	60	struct twl4030_keypad {
	61	unsigned short keymap[TWL4030_KEYMAP_SIZE];
	62	u16 kp_state[TWL4030_MAX_ROWS];
7abf38d6	63	bool autorepeat;
9d834068 DB	64	unsigned n_rows;
	65	unsigned n_cols;
	66	unsigned irq;
	67
	68	struct device *dbg_dev;
	69	struct input_dev *input;
	70	};
	71
	72	/----------------------------------------------------------------------/
	73
	74	/* arbitrary prescaler value 0..7 */
	75	#define PTV_PRESCALER 4
	76
	77	/* Register Offsets */
	78	#define KEYP_CTRL 0x00
	79	#define KEYP_DEB 0x01
	80	#define KEYP_LONG_KEY 0x02
	81	#define KEYP_LK_PTV 0x03
	82	#define KEYP_TIMEOUT_L 0x04
	83	#define KEYP_TIMEOUT_H 0x05
	84	#define KEYP_KBC 0x06
	85	#define KEYP_KBR 0x07
	86	#define KEYP_SMS 0x08
	87	#define KEYP_FULL_CODE_7_0 0x09 /* row 0 column status */
	88	#define KEYP_FULL_CODE_15_8 0x0a /* ... row 1 ... */
	89	#define KEYP_FULL_CODE_23_16 0x0b
	90	#define KEYP_FULL_CODE_31_24 0x0c
	91	#define KEYP_FULL_CODE_39_32 0x0d
	92	#define KEYP_FULL_CODE_47_40 0x0e
	93	#define KEYP_FULL_CODE_55_48 0x0f
	94	#define KEYP_FULL_CODE_63_56 0x10
	95	#define KEYP_ISR1 0x11
	96	#define KEYP_IMR1 0x12
	97	#define KEYP_ISR2 0x13
	98	#define KEYP_IMR2 0x14
	99	#define KEYP_SIR 0x15
	100	#define KEYP_EDR 0x16 /* edge triggers */
	101	#define KEYP_SIH_CTRL 0x17
	102
	103	/* KEYP_CTRL_REG Fields */
	104	#define KEYP_CTRL_SOFT_NRST BIT(0)
	105	#define KEYP_CTRL_SOFTMODEN BIT(1)
	106	#define KEYP_CTRL_LK_EN BIT(2)
	107	#define KEYP_CTRL_TOE_EN BIT(3)
	108	#define KEYP_CTRL_TOLE_EN BIT(4)
	109	#define KEYP_CTRL_RP_EN BIT(5)
	110	#define KEYP_CTRL_KBD_ON BIT(6)
	111
	112	/* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
	113	#define KEYP_PERIOD_US(t, prescale) ((t) / (31 << (prescale + 1)) - 1)
	114
	115	/* KEYP_LK_PTV_REG Fields */
	116	#define KEYP_LK_PTV_PTV_SHIFT 5
	117
	118	/* KEYP_{IMR,ISR,SIR} Fields */
	119	#define KEYP_IMR1_MIS BIT(3)
	120	#define KEYP_IMR1_TO BIT(2)
	121	#define KEYP_IMR1_LK BIT(1)
	122	#define KEYP_IMR1_KP BIT(0)
	123
	124	/* KEYP_EDR Fields */
	125	#define KEYP_EDR_KP_FALLING 0x01
	126	#define KEYP_EDR_KP_RISING 0x02
	127	#define KEYP_EDR_KP_BOTH 0x03
128	#define KEYP_EDR_LK_FALLING 0x04
129	#define KEYP_EDR_LK_RISING 0x08
130	#define KEYP_EDR_TO_FALLING 0x10
131	#define KEYP_EDR_TO_RISING 0x20
132	#define KEYP_EDR_MIS_FALLING 0x40
133	#define KEYP_EDR_MIS_RISING 0x80
134
135
136	/----------------------------------------------------------------------/
137
138	static int twl4030_kpread(struct twl4030_keypad *kp,
139	u8 *data, u32 reg, u8 num_bytes)
140	{
fc7b92fc	141	int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);
9d834068 DB	142
	143	if (ret < 0)
	144	dev_warn(kp->dbg_dev,
	145	"Couldn't read TWL4030: %X - ret %d[%x]\n",
	146	reg, ret, ret);
	147
	148	return ret;
	149	}
	150
	151	static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
	152	{
fc7b92fc	153	int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);
9d834068 DB	154
	155	if (ret < 0)
	156	dev_warn(kp->dbg_dev,
	157	"Could not write TWL4030: %X - ret %d[%x]\n",
	158	reg, ret, ret);
	159
	160	return ret;
	161	}
	162
	163	static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
	164	{
	165	/* If all bits in a row are active for all coloumns then
	166	* we have that row line connected to gnd. Mark this
	167	* key on as if it was on matrix position n_cols (ie
	168	* one higher than the size of the matrix).
	169	*/
	170	if (col == 0xFF)
	171	return 1 << kp->n_cols;
	172	else
	173	return col & ((1 << kp->n_cols) - 1);
	174	}
	175
	176	static int twl4030_read_kp_matrix_state(struct twl4030_keypad kp, u16 state)
	177	{
	178	u8 new_state[TWL4030_MAX_ROWS];
	179	int row;
	180	int ret = twl4030_kpread(kp, new_state,
	181	KEYP_FULL_CODE_7_0, kp->n_rows);
	182	if (ret >= 0)
	183	for (row = 0; row < kp->n_rows; row++)
	184	state[row] = twl4030_col_xlate(kp, new_state[row]);
	185
	186	return ret;
	187	}
	188
3fea6026	189	static bool twl4030_is_in_ghost_state(struct twl4030_keypad kp, u16 key_state)
9d834068 DB	190	{
	191	int i;
	192	u16 check = 0;
	193
	194	for (i = 0; i < kp->n_rows; i++) {
	195	u16 col = key_state[i];
	196
	197	if ((col & check) && hweight16(col) > 1)
3fea6026	198	return true;
9d834068 DB	199
	200	check \|= col;
	201	}
	202
3fea6026	203	return false;
9d834068 DB	204	}
	205
	206	static void twl4030_kp_scan(struct twl4030_keypad *kp, bool release_all)
	207	{
	208	struct input_dev *input = kp->input;
	209	u16 new_state[TWL4030_MAX_ROWS];
	210	int col, row;
	211
	212	if (release_all)
	213	memset(new_state, 0, sizeof(new_state));
	214	else {
	215	/* check for any changes */
	216	int ret = twl4030_read_kp_matrix_state(kp, new_state);
	217
	218	if (ret < 0) /* panic ... */
	219	return;
	220
	221	if (twl4030_is_in_ghost_state(kp, new_state))
	222	return;
	223	}
	224
	225	/* check for changes and print those */
	226	for (row = 0; row < kp->n_rows; row++) {
	227	int changed = new_state[row] ^ kp->kp_state[row];
	228
	229	if (!changed)
	230	continue;
	231
3fea6026 DT	232	/* Extra column handles "all gnd" rows */
3fea6026 DT	233	for (col = 0; col < kp->n_cols + 1; col++) {
9d834068 DB	234	int code;
	235
	236	if (!(changed & (1 << col)))
	237	continue;
	238
	239	dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
	240	(new_state[row] & (1 << col)) ?
	241	"press" : "release");
	242
	243	code = MATRIX_SCAN_CODE(row, col, TWL4030_ROW_SHIFT);
	244	input_event(input, EV_MSC, MSC_SCAN, code);
	245	input_report_key(input, kp->keymap[code],
	246	new_state[row] & (1 << col));
	247	}
	248	kp->kp_state[row] = new_state[row];
	249	}
	250	input_sync(input);
	251	}
	252
	253	/*
	254	* Keypad interrupt handler
	255	*/
	256	static irqreturn_t do_kp_irq(int irq, void *_kp)
	257	{
	258	struct twl4030_keypad *kp = _kp;
	259	u8 reg;
	260	int ret;
	261
9d834068 DB	262	/* Read & Clear TWL4030 pending interrupt */
	263	ret = twl4030_kpread(kp, &reg, KEYP_ISR1, 1);
	264
	265	/* Release all keys if I2C has gone bad or
	266	* the KEYP has gone to idle state */
	267	if (ret >= 0 && (reg & KEYP_IMR1_KP))
	268	twl4030_kp_scan(kp, false);
	269	else
	270	twl4030_kp_scan(kp, true);
	271
	272	return IRQ_HANDLED;
	273	}
	274
5298cc4c	275	static int twl4030_kp_program(struct twl4030_keypad *kp)
9d834068 DB	276	{
	277	u8 reg;
	278	int i;
	279
	280	/* Enable controller, with hardware decoding but not autorepeat */
	281	reg = KEYP_CTRL_SOFT_NRST \| KEYP_CTRL_SOFTMODEN
	282	\| KEYP_CTRL_TOE_EN \| KEYP_CTRL_KBD_ON;
	283	if (twl4030_kpwrite_u8(kp, reg, KEYP_CTRL) < 0)
	284	return -EIO;
	285
	286	/* NOTE: we could use sih_setup() here to package keypad
	287	* event sources as four different IRQs ... but we don't.
	288	*/
	289
	290	/* Enable TO rising and KP rising and falling edge detection */
	291	reg = KEYP_EDR_KP_BOTH \| KEYP_EDR_TO_RISING;
	292	if (twl4030_kpwrite_u8(kp, reg, KEYP_EDR) < 0)
	293	return -EIO;
	294
	295	/* Set PTV prescaler Field */
	296	reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
	297	if (twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV) < 0)
	298	return -EIO;
	299
	300	/* Set key debounce time to 20 ms */
	301	i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
	302	if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
	303	return -EIO;
	304
4936f97c	305	/* Set timeout period to 200 ms */
9d834068 DB	306	i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
	307	if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
	308	return -EIO;
	309
	310	if (twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H) < 0)
	311	return -EIO;
	312
	313	/*
	314	* Enable Clear-on-Read; disable remembering events that fire
	315	* after the IRQ but before our handler acks (reads) them,
	316	*/
	317	reg = TWL4030_SIH_CTRL_COR_MASK \| TWL4030_SIH_CTRL_PENDDIS_MASK;
	318	if (twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL) < 0)
	319	return -EIO;
	320
	321	/* initialize key state; irqs update it from here on */
	322	if (twl4030_read_kp_matrix_state(kp, kp->kp_state) < 0)
	323	return -EIO;
	324
	325	return 0;
	326	}
	327
	328	/*
	329	* Registers keypad device with input subsystem
	330	* and configures TWL4030 keypad registers
	331	*/
5298cc4c	332	static int twl4030_kp_probe(struct platform_device *pdev)
9d834068	333	{
c838cb3d	334	struct twl4030_keypad_data *pdata = dev_get_platdata(&pdev->dev);
7abf38d6	335	const struct matrix_keymap_data *keymap_data = NULL;
9d834068 DB	336	struct twl4030_keypad *kp;
	337	struct input_dev *input;
	338	u8 reg;
	339	int error;
	340
049f1cb2 DT	341	kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL);
	342	if (!kp)
	343	return -ENOMEM;
	344
	345	input = devm_input_allocate_device(&pdev->dev);
	346	if (!input)
	347	return -ENOMEM;
9d834068	348
7abf38d6 SR	349	/* get the debug device */
	350	kp->dbg_dev = &pdev->dev;
	351	kp->input = input;
9d834068 DB	352
9d834068 DB	353	/* setup input device */
9d834068 DB	354	input->name = "TWL4030 Keypad";
9d834068 DB	355	input->phys = "twl4030_keypad/input0";
9d834068 DB	356
	357	input->id.bustype = BUS_HOST;
	358	input->id.vendor = 0x0001;
	359	input->id.product = 0x0001;
	360	input->id.version = 0x0003;
	361
7abf38d6 SR	362	if (pdata) {
	363	if (!pdata->rows \|\| !pdata->cols \|\| !pdata->keymap_data) {
	364	dev_err(&pdev->dev, "Missing platform_data\n");
049f1cb2	365	return -EINVAL;
7abf38d6 SR	366	}
	367
	368	kp->n_rows = pdata->rows;
	369	kp->n_cols = pdata->cols;
	370	kp->autorepeat = pdata->rep;
	371	keymap_data = pdata->keymap_data;
	372	} else {
	373	error = matrix_keypad_parse_of_params(&pdev->dev, &kp->n_rows,
	374	&kp->n_cols);
	375	if (error)
049f1cb2	376	return error;
7abf38d6 SR	377
	378	kp->autorepeat = true;
	379	}
	380
	381	if (kp->n_rows > TWL4030_MAX_ROWS \|\| kp->n_cols > TWL4030_MAX_COLS) {
	382	dev_err(&pdev->dev,
	383	"Invalid rows/cols amount specified in platform/devicetree data\n");
049f1cb2	384	return -EINVAL;
7abf38d6 SR	385	}
	386
	387	kp->irq = platform_get_irq(pdev, 0);
	388	if (!kp->irq) {
	389	dev_err(&pdev->dev, "no keyboard irq assigned\n");
049f1cb2	390	return -EINVAL;
7abf38d6 SR	391	}
7abf38d6 SR	392
1932811f DT	393	error = matrix_keypad_build_keymap(keymap_data, NULL,
	394	TWL4030_MAX_ROWS,
	395	1 << TWL4030_ROW_SHIFT,
	396	kp->keymap, input);
	397	if (error) {
	398	dev_err(kp->dbg_dev, "Failed to build keymap\n");
049f1cb2	399	return error;
1932811f	400	}
9d834068	401
1932811f DT	402	input_set_capability(input, EV_MSC, MSC_SCAN);
1932811f DT	403	/* Enable auto repeat feature of Linux input subsystem */
7abf38d6	404	if (kp->autorepeat)
1932811f	405	__set_bit(EV_REP, input->evbit);
9d834068 DB	406
	407	error = input_register_device(input);
	408	if (error) {
	409	dev_err(kp->dbg_dev,
	410	"Unable to register twl4030 keypad device\n");
049f1cb2	411	return error;
9d834068 DB	412	}
	413
	414	error = twl4030_kp_program(kp);
	415	if (error)
049f1cb2	416	return error;
9d834068 DB	417
	418	/*
	419	* This ISR will always execute in kernel thread context because of
	420	* the need to access the TWL4030 over the I2C bus.
	421	*
	422	* NOTE: we assume this host is wired to TWL4040 INT1, not INT2 ...
	423	*/
049f1cb2 DT	424	error = devm_request_threaded_irq(&pdev->dev, kp->irq, NULL, do_kp_irq,
049f1cb2 DT	425	0, pdev->name, kp);
9d834068	426	if (error) {
049f1cb2 DT	427	dev_info(kp->dbg_dev, "request_irq failed for irq no=%d: %d\n",
	428	kp->irq, error);
	429	return error;
9d834068 DB	430	}
	431
	432	/* Enable KP and TO interrupts now. */
	433	reg = (u8) ~(KEYP_IMR1_KP \| KEYP_IMR1_TO);
	434	if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) {
049f1cb2 DT	435	/* mask all events - we don't care about the result */
	436	(void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
	437	return -EIO;
9d834068 DB	438	}
	439
	440	platform_set_drvdata(pdev, kp);
	441	return 0;
9d834068 DB	442	}
9d834068 DB	443
7abf38d6 SR	444	#ifdef CONFIG_OF
	445	static const struct of_device_id twl4030_keypad_dt_match_table[] = {
	446	{ .compatible = "ti,twl4030-keypad" },
	447	{},
	448	};
	449	MODULE_DEVICE_TABLE(of, twl4030_keypad_dt_match_table);
	450	#endif
	451
9d834068 DB	452	/*
	453	* NOTE: twl4030 are multi-function devices connected via I2C.
	454	* So this device is a child of an I2C parent, thus it needs to
	455	* support unplug/replug (which most platform devices don't).
	456	*/
	457
	458	static struct platform_driver twl4030_kp_driver = {
	459	.probe = twl4030_kp_probe,
9d834068 DB	460	.driver = {
9d834068 DB	461	.name = "twl4030_keypad",
7abf38d6	462	.of_match_table = of_match_ptr(twl4030_keypad_dt_match_table),
9d834068 DB	463	},
9d834068 DB	464	};
5146c84f	465	module_platform_driver(twl4030_kp_driver);
9d834068 DB	466
	467	MODULE_AUTHOR("Texas Instruments");
	468	MODULE_DESCRIPTION("TWL4030 Keypad Driver");
	469	MODULE_LICENSE("GPL");
	470	MODULE_ALIAS("platform:twl4030_keypad");