Release 4.11 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 int	n_rows;
	
unsigned int	n_cols;
	
unsigned int	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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
58
98.31%
1
50.00%
Balaji T K
1
1.69%
1
50.00%
Total
59
100.00%
2
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
52
98.11%
1
50.00%
Balaji T K
1
1.89%
1
50.00%
Total
53
100.00%
2
100.00%



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

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
44
97.78%
1
50.00%
Rui Teng
1
2.22%
1
50.00%
Total
45
100.00%
2
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
79
100.00%
1
100.00%
Total
79
100.00%
1
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
70
95.89%
1
50.00%
Dmitry Torokhov
3
4.11%
1
50.00%
Total
73
100.00%
2
100.00%



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);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
247
98.02%
1
33.33%
Dmitry Torokhov
3
1.19%
1
33.33%
Rui Teng
2
0.79%
1
33.33%
Total
252
100.00%
3
100.00%

/*
 * 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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
71
98.61%
1
50.00%
Rui Teng
1
1.39%
1
50.00%
Total
72
100.00%
2
100.00%



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;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
217
98.64%
1
33.33%
Rui Teng
2
0.91%
1
33.33%
Felipe Contreras
1
0.45%
1
33.33%
Total
220
100.00%
3
100.00%

/*
 * 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_properties(&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;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
259
49.43%
1
14.29%
Sebastian Reichel
164
31.30%
1
14.29%
Dmitry Torokhov
95
18.13%
3
42.86%
Jingoo Han
4
0.76%
1
14.29%
Felipe Balbi
2
0.38%
1
14.29%
Total
524
100.00%
7
100.00%

#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");
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
David Brownell
1423
80.99%
1
7.14%
Sebastian Reichel
206
11.72%
1
7.14%
Dmitry Torokhov
104
5.92%
4
28.57%
Rui Teng
10
0.57%
1
7.14%
Jingoo Han
4
0.23%
1
7.14%
Tejun Heo
3
0.17%
1
7.14%
Balaji T K
2
0.11%
1
7.14%
Felipe Balbi
2
0.11%
1
7.14%
Santosh Shilimkar
1
0.06%
1
7.14%
Felipe Contreras
1
0.06%
1
7.14%
JJ Ding
1
0.06%
1
7.14%
Total
1757
100.00%
14
100.00%
Directory: drivers/input/keyboard

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.