diff options
Diffstat (limited to 'drivers/input/keyboard/twl4030_keypad.c')
| -rw-r--r-- | drivers/input/keyboard/twl4030_keypad.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/drivers/input/keyboard/twl4030_keypad.c b/drivers/input/keyboard/twl4030_keypad.c new file mode 100644 index 000000000..8677dbe0f --- /dev/null +++ b/drivers/input/keyboard/twl4030_keypad.c @@ -0,0 +1,471 @@ +/* + * 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/mfd/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; + 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; +} + +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 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); +} + +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 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_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 < 0) + return kp->irq; + + 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; +} + +#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"); |