/* * 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/init.h> #include <linux/interrupt.h> #include <linux/input.h> #include <linux/platform_device.h> #include <linux/i2c/twl.h> #include <linux/slab.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]; 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, ®, 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 __devinit 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 100 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 __devinit twl4030_kp_probe(struct platform_device *pdev) { struct twl4030_keypad_data *pdata = pdev->dev.platform_data; const struct matrix_keymap_data *keymap_data = pdata->keymap_data; struct twl4030_keypad *kp; struct input_dev *input; u8 reg; int error; if (!pdata || !pdata->rows || !pdata->cols || pdata->rows > TWL4030_MAX_ROWS || pdata->cols > TWL4030_MAX_COLS) { dev_err(&pdev->dev, "Invalid platform_data\n"); return -EINVAL; } kp = kzalloc(sizeof(*kp), GFP_KERNEL); input = input_allocate_device(); if (!kp || !input) { error = -ENOMEM; goto err1; } /* Get the debug Device */ kp->dbg_dev = &pdev->dev; kp->input = input; kp->n_rows = pdata->rows; kp->n_cols = pdata->cols; kp->irq = platform_get_irq(pdev, 0); /* setup input device */ __set_bit(EV_KEY, input->evbit); /* Enable auto repeat feature of Linux input subsystem */ if (pdata->rep) __set_bit(EV_REP, input->evbit); input_set_capability(input, EV_MSC, MSC_SCAN); input->name = "TWL4030 Keypad"; input->phys = "twl4030_keypad/input0"; input->dev.parent = &pdev->dev; input->id.bustype = BUS_HOST; input->id.vendor = 0x0001; input->id.product = 0x0001; input->id.version = 0x0003; input->keycode = kp->keymap; input->keycodesize = sizeof(kp->keymap[0]); input->keycodemax = ARRAY_SIZE(kp->keymap); matrix_keypad_build_keymap(keymap_data, TWL4030_ROW_SHIFT, input->keycode, input->keybit); error = input_register_device(input); if (error) { dev_err(kp->dbg_dev, "Unable to register twl4030 keypad device\n"); goto err1; } error = twl4030_kp_program(kp); if (error) goto err2; /* * 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 = request_threaded_irq(kp->irq, NULL, do_kp_irq, 0, pdev->name, kp); if (error) { dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n", kp->irq); goto err3; } /* Enable KP and TO interrupts now. */ reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO); if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) { error = -EIO; goto err4; } platform_set_drvdata(pdev, kp); return 0; err4: /* mask all events - we don't care about the result */ (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1); err3: free_irq(kp->irq, NULL); err2: input_unregister_device(input); input = NULL; err1: input_free_device(input); kfree(kp); return error; } static int __devexit twl4030_kp_remove(struct platform_device *pdev) { struct twl4030_keypad *kp = platform_get_drvdata(pdev); free_irq(kp->irq, kp); input_unregister_device(kp->input); platform_set_drvdata(pdev, NULL); kfree(kp); return 0; } /* * 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, .remove = __devexit_p(twl4030_kp_remove), .driver = { .name = "twl4030_keypad", .owner = THIS_MODULE, }, }; static int __init twl4030_kp_init(void) { return platform_driver_register(&twl4030_kp_driver); } module_init(twl4030_kp_init); static void __exit twl4030_kp_exit(void) { platform_driver_unregister(&twl4030_kp_driver); } module_exit(twl4030_kp_exit); MODULE_AUTHOR("Texas Instruments"); MODULE_DESCRIPTION("TWL4030 Keypad Driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:twl4030_keypad");