cregit-Linux how code gets into the kernel

Release 4.7 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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell5898.31%150.00%
balaji t kbalaji t k11.69%150.00%
Total59100.00%2100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell5298.11%150.00%
balaji t kbalaji t k11.89%150.00%
Total53100.00%2100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell4497.78%150.00%
rui tengrui teng12.22%150.00%
Total45100.00%2100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell79100.00%1100.00%
Total79100.00%1100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell7095.89%150.00%
dmitry torokhovdmitry torokhov34.11%150.00%
Total73100.00%2100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell24798.02%133.33%
dmitry torokhovdmitry torokhov31.19%133.33%
rui tengrui teng20.79%133.33%
Total252100.00%3100.00%

/* * 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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell7198.61%150.00%
rui tengrui teng11.39%150.00%
Total72100.00%2100.00%


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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell21798.64%133.33%
rui tengrui teng20.91%133.33%
felipe contrerasfelipe contreras10.45%133.33%
Total220100.00%3100.00%

/* * 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_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; }

Contributors

PersonTokensPropCommitsCommitProp
david brownelldavid brownell26549.91%116.67%
sebastian reichelsebastian reichel16531.07%116.67%
dmitry torokhovdmitry torokhov9517.89%233.33%
jingoo hanjingoo han40.75%116.67%
felipe balbifelipe balbi20.38%116.67%
Total531100.00%6100.00%

#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

PersonTokensPropCommitsCommitProp
david brownelldavid brownell142981.01%17.69%
sebastian reichelsebastian reichel20711.73%17.69%
dmitry torokhovdmitry torokhov1045.90%323.08%
rui tengrui teng100.57%17.69%
jingoo hanjingoo han40.23%17.69%
tejun heotejun heo30.17%17.69%
balaji t kbalaji t k20.11%17.69%
felipe balbifelipe balbi20.11%17.69%
jj dingjj ding10.06%17.69%
santosh shilimkarsantosh shilimkar10.06%17.69%
felipe contrerasfelipe contreras10.06%17.69%
Total1764100.00%13100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}