// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include <linux/of.h>
#include <linux/input/matrix_keypad.h>
#define PM8XXX_MAX_ROWS 18
#define PM8XXX_MAX_COLS 8
#define PM8XXX_ROW_SHIFT 3
#define PM8XXX_MATRIX_MAX_SIZE (PM8XXX_MAX_ROWS * PM8XXX_MAX_COLS)
#define PM8XXX_MIN_ROWS 5
#define PM8XXX_MIN_COLS 5
#define MAX_SCAN_DELAY 128
#define MIN_SCAN_DELAY 1
/* in nanoseconds */
#define MAX_ROW_HOLD_DELAY 122000
#define MIN_ROW_HOLD_DELAY 30500
#define MAX_DEBOUNCE_TIME 20
#define MIN_DEBOUNCE_TIME 5
#define KEYP_CTRL 0x148
#define KEYP_CTRL_EVNTS BIT(0)
#define KEYP_CTRL_EVNTS_MASK 0x3
#define KEYP_CTRL_SCAN_COLS_SHIFT 5
#define KEYP_CTRL_SCAN_COLS_MIN 5
#define KEYP_CTRL_SCAN_COLS_BITS 0x3
#define KEYP_CTRL_SCAN_ROWS_SHIFT 2
#define KEYP_CTRL_SCAN_ROWS_MIN 5
#define KEYP_CTRL_SCAN_ROWS_BITS 0x7
#define KEYP_CTRL_KEYP_EN BIT(7)
#define KEYP_SCAN 0x149
#define KEYP_SCAN_READ_STATE BIT(0)
#define KEYP_SCAN_DBOUNCE_SHIFT 1
#define KEYP_SCAN_PAUSE_SHIFT 3
#define KEYP_SCAN_ROW_HOLD_SHIFT 6
#define KEYP_TEST 0x14A
#define KEYP_TEST_CLEAR_RECENT_SCAN BIT(6)
#define KEYP_TEST_CLEAR_OLD_SCAN BIT(5)
#define KEYP_TEST_READ_RESET BIT(4)
#define KEYP_TEST_DTEST_EN BIT(3)
#define KEYP_TEST_ABORT_READ BIT(0)
#define KEYP_TEST_DBG_SELECT_SHIFT 1
/* bits of these registers represent
* '0' for key press
* '1' for key release
*/
#define KEYP_RECENT_DATA 0x14B
#define KEYP_OLD_DATA 0x14C
#define KEYP_CLOCK_FREQ 32768
/**
* struct pmic8xxx_kp - internal keypad data structure
* @num_cols: number of columns of keypad
* @num_rows: number of row of keypad
* @input: input device pointer for keypad
* @regmap: regmap handle
* @key_sense_irq: key press/release irq number
* @key_stuck_irq: key stuck notification irq number
* @keycodes: array to hold the key codes
* @dev: parent device pointer
* @keystate: present key press/release state
* @stuckstate: present state when key stuck irq
* @ctrl_reg: control register value
*/
struct pmic8xxx_kp {
unsigned int num_rows;
unsigned int num_cols;
struct input_dev *input;
struct regmap *regmap;
int key_sense_irq;
int key_stuck_irq;
unsigned short keycodes[PM8XXX_MATRIX_MAX_SIZE];
struct device *dev;
u16 keystate[PM8XXX_MAX_ROWS];
u16 stuckstate[PM8XXX_MAX_ROWS];
u8 ctrl_reg;
};
static u8 pmic8xxx_col_state(struct pmic8xxx_kp *kp, u8 col)
{
/* all keys pressed on that particular row? */
if (col == 0x00)
return 1 << kp->num_cols;
else
return col & ((1 << kp->num_cols) - 1);
}
/*
* Synchronous read protocol for RevB0 onwards:
*
* 1. Write '1' to ReadState bit in KEYP_SCAN register
* 2. Wait 2*32KHz clocks, so that HW can successfully enter read mode
* synchronously
* 3. Read rows in old array first if events are more than one
* 4. Read rows in recent array
* 5. Wait 4*32KHz clocks
* 6. Write '0' to ReadState bit of KEYP_SCAN register so that hw can
* synchronously exit read mode.
*/
static int pmic8xxx_chk_sync_read(struct pmic8xxx_kp *kp)
{
int rc;
unsigned int scan_val;
rc = regmap_read(kp->regmap, KEYP_SCAN, &scan_val);
if (rc < 0) {
dev_err(kp->dev, "Error reading KEYP_SCAN reg, rc=%d\n", rc);
return rc;
}
scan_val |= 0x1;
rc = regmap_write(kp->regmap, KEYP_SCAN, scan_val);
if (rc < 0) {
dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);
return rc;
}
/* 2 * 32KHz clocks */
udelay((2 * DIV_ROUND_UP(USEC_PER_SEC, KEYP_CLOCK_FREQ)) + 1);
return rc;
}
static int pmic8xxx_kp_read_data(struct pmic8xxx_kp *kp, u16 *state,
u16 data_reg, int read_rows)
{
int rc, row;
unsigned int val;
for (row = 0; row < read_rows; row++) {
rc = regmap_read(kp->regmap, data_reg, &val);
if (rc)
return rc;
dev_dbg(kp->dev, "%d = %d\n", row, val);
state[row] = pmic8xxx_col_state(kp, val);
}
return 0;
}
static int pmic8xxx_kp_read_matrix(struct pmic8xxx_kp *kp, u16 *new_state,
u16 *old_state)
{
int rc, read_rows;
unsigned int scan_val;
if (kp->num_rows < PM8XXX_MIN_ROWS)
read_rows = PM8XXX_MIN_ROWS;
else
read_rows = kp->num_rows;
pmic8xxx_chk_sync_read(kp);
if (old_state) {
rc = pmic8xxx_kp_read_data(kp, old_state, KEYP_OLD_DATA,
read_rows);
if (rc < 0) {
dev_err(kp->dev,
"Error reading KEYP_OLD_DATA, rc=%d\n", rc);
return rc;
}
}
rc = pmic8xxx_kp_read_data(kp, new_state, KEYP_RECENT_DATA,
read_rows);
if (rc < 0) {
dev_err(kp->dev,
"Error reading KEYP_RECENT_DATA, rc=%d\n", rc);
return rc;
}
/* 4 * 32KHz clocks */
udelay((4 * DIV_ROUND_UP(USEC_PER_SEC, KEYP_CLOCK_FREQ)) + 1);
rc = regmap_read(kp->regmap, KEYP_SCAN, &scan_val);
if (rc < 0) {
dev_err(kp->dev, "Error reading KEYP_SCAN reg, rc=%d\n", rc);
return rc;
}
scan_val &= 0xFE;
rc = regmap_write(kp->regmap, KEYP_SCAN, scan_val);
if (rc < 0)
dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);
return rc;
}
static void __pmic8xxx_kp_scan_matrix(struct pmic8xxx_kp *kp, u16 *new_state,
u16 *old_state)
{
int row, col, code;
for (row = 0; row < kp->num_rows; row++) {
int bits_changed = new_state[row] ^ old_state[row];
if (!bits_changed)
continue;
for (col = 0; col < kp->num_cols; col++) {
if (!(bits_changed & (1 << col)))
continue;
dev_dbg(kp->dev, "key [%d:%d] %s\n", row, col,
!(new_state[row] & (1 << col)) ?
"pressed" : "released");
code = MATRIX_SCAN_CODE(row, col, PM8XXX_ROW_SHIFT);
input_event(kp->input, EV_MSC, MSC_SCAN, code);
input_report_key(kp->input,
kp->keycodes[code],
!(new_state[row] & (1 << col)));
input_sync(kp->input);
}
}
}
static bool pmic8xxx_detect_ghost_keys(struct pmic8xxx_kp *kp, u16 *new_state)
{
int row, found_first = -1;
u16 check, row_state;
check = 0;
for (row = 0; row < kp->num_rows; row++) {
row_state = (~new_state[row]) &
((1 << kp->num_cols) - 1);
if (hweight16(row_state) > 1) {
if (found_first == -1)
found_first = row;
if (check & row_state) {
dev_dbg(kp->dev, "detected ghost key on row[%d]"
" and row[%d]\n", found_first, row);
return true;
}
}
check |= row_state;
}
return false;
}
static int pmic8xxx_kp_scan_matrix(struct pmic8xxx_kp *kp, unsigned int events)
{
u16 new_state[PM8XXX_MAX_ROWS];
u16 old_state[PM8XXX_MAX_ROWS];
int rc;
switch (events) {
case 0x1:
rc = pmic8xxx_kp_read_matrix(kp, new_state, NULL);
if (rc < 0)
return rc;
/* detecting ghost key is not an error */
if (pmic8xxx_detect_ghost_keys(kp, new_state))
return 0;
__pmic8xxx_kp_scan_matrix(kp, new_state, kp->keystate);
memcpy(kp->keystate, new_state, sizeof(new_state));
break;
case 0x3: /* two events - eventcounter is gray-coded */
rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
if (rc < 0)
return rc;
__pmic8xxx_kp_scan_matrix(kp, old_state, kp->keystate);
__pmic8xxx_kp_scan_matrix(kp, new_state, old_state);
memcpy(kp->keystate, new_state, sizeof(new_state));
break;
case 0x2:
dev_dbg(kp->dev, "Some key events were lost\n");
rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
if (rc < 0)
return rc;
__pmic8xxx_kp_scan_matrix(kp, old_state, kp->keystate);
__pmic8xxx_kp_scan_matrix(kp, new_state, old_state);
memcpy(kp->keystate, new_state, sizeof(new_state));
break;
default:
rc = -EINVAL;
}
return rc;
}
/*
* NOTE: We are reading recent and old data registers blindly
* whenever key-stuck interrupt happens, because events counter doesn't
* get updated when this interrupt happens due to key stuck doesn't get
* considered as key state change.
*
* We are not using old data register contents after they are being read
* because it might report the key which was pressed before the key being stuck
* as stuck key because it's pressed status is stored in the old data
* register.
*/
static irqreturn_t pmic8xxx_kp_stuck_irq(int irq, void *data)
{
u16 new_state[PM8XXX_MAX_ROWS];
u16 old_state[PM8XXX_MAX_ROWS];
int rc;
struct pmic8xxx_kp *kp = data;
rc = pmic8xxx_kp_read_matrix(kp, new_state, old_state);
if (rc < 0) {
dev_err(kp->dev, "failed to read keypad matrix\n");
return IRQ_HANDLED;
}
__pmic8xxx_kp_scan_matrix(kp, new_state, kp->stuckstate);
return IRQ_HANDLED;
}
static irqreturn_t pmic8xxx_kp_irq(int irq, void *data)
{
struct pmic8xxx_kp *kp = data;
unsigned int ctrl_val, events;
int rc;
rc = regmap_read(kp->regmap, KEYP_CTRL, &ctrl_val);
if (rc < 0) {
dev_err(kp->dev, "failed to read keyp_ctrl register\n");
return IRQ_HANDLED;
}
events = ctrl_val & KEYP_CTRL_EVNTS_MASK;
rc = pmic8xxx_kp_scan_matrix(kp, events);
if (rc < 0)
dev_err(kp->dev, "failed to scan matrix\n");
return IRQ_HANDLED;
}
static int pmic8xxx_kpd_init(struct pmic8xxx_kp *kp,
struct platform_device *pdev)
{
const struct device_node *of_node = pdev->dev.of_node;
unsigned int scan_delay_ms;
unsigned int row_hold_ns;
unsigned int debounce_ms;
int bits, rc, cycles;
u8 scan_val = 0, ctrl_val = 0;
static const u8 row_bits[] = {
0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 7, 7, 7,
};
/* Find column bits */
if (kp->num_cols < KEYP_CTRL_SCAN_COLS_MIN)
bits = 0;
else
bits = kp->num_cols - KEYP_CTRL_SCAN_COLS_MIN;
ctrl_val = (bits & KEYP_CTRL_SCAN_COLS_BITS) <<
KEYP_CTRL_SCAN_COLS_SHIFT;
/* Find row bits */
if (kp->num_rows < KEYP_CTRL_SCAN_ROWS_MIN)
bits = 0;
else
bits = row_bits[kp->num_rows - KEYP_CTRL_SCAN_ROWS_MIN];
ctrl_val |= (bits << KEYP_CTRL_SCAN_ROWS_SHIFT);
rc = regmap_write(kp->regmap, KEYP_CTRL, ctrl_val);
if (rc < 0) {
dev_err(kp->dev, "Error writing KEYP_CTRL reg, rc=%d\n", rc);
return rc;
}
if (of_property_read_u32(of_node, "scan-delay", &scan_delay_ms))
scan_delay_ms = MIN_SCAN_DELAY;
if (scan_delay_ms > MAX_SCAN_DELAY || scan_delay_ms < MIN_SCAN_DELAY ||
!is_power_of_2(scan_delay_ms)) {
dev_err(&pdev->dev, "invalid keypad scan time supplied\n");
return -EINVAL;
}
if (of_property_read_u32(of_node, "row-hold", &row_hold_ns))
row_hold_ns = MIN_ROW_HOLD_DELAY;
if (row_hold_ns > MAX_ROW_HOLD_DELAY ||
row_hold_ns < MIN_ROW_HOLD_DELAY ||
((row_hold_ns % MIN_ROW_HOLD_DELAY) != 0)) {
dev_err(&pdev->dev, "invalid keypad row hold time supplied\n");
return -EINVAL;
}
if (of_property_read_u32(of_node, "debounce", &debounce_ms))
debounce_ms = MIN_DEBOUNCE_TIME;
if (((debounce_ms % 5) != 0) ||
debounce_ms > MAX_DEBOUNCE_TIME ||
debounce_ms < MIN_DEBOUNCE_TIME) {
dev_err(&pdev->dev, "invalid debounce time supplied\n");
return -EINVAL;
}
bits = (debounce_ms / 5) - 1;
scan_val |= (bits << KEYP_SCAN_DBOUNCE_SHIFT);
bits = fls(scan_delay_ms) - 1;
scan_val |= (bits << KEYP_SCAN_PAUSE_SHIFT);
/* Row hold time is a multiple of 32KHz cycles. */
cycles = (row_hold_ns * KEYP_CLOCK_FREQ) / NSEC_PER_SEC;
scan_val |= (cycles << KEYP_SCAN_ROW_HOLD_SHIFT);
rc = regmap_write(kp->regmap, KEYP_SCAN, scan_val);
if (rc)
dev_err(kp->dev, "Error writing KEYP_SCAN reg, rc=%d\n", rc);
return rc;
}
static int pmic8xxx_kp_enable(struct pmic8xxx_kp *kp)
{
int rc;
kp->ctrl_reg |= KEYP_CTRL_KEYP_EN;
rc = regmap_write(kp->regmap, KEYP_CTRL, kp->ctrl_reg);
if (rc < 0)
dev_err(kp->dev, "Error writing KEYP_CTRL reg, rc=%d\n", rc);
return rc;
}
static int pmic8xxx_kp_disable(struct pmic8xxx_kp *kp)
{
int rc;
kp->ctrl_reg &= ~KEYP_CTRL_KEYP_EN;
rc = regmap_write(kp->regmap, KEYP_CTRL, kp->ctrl_reg);
if (rc < 0)
return rc;
return rc;
}
static int pmic8xxx_kp_open(struct input_dev *dev)
{
struct pmic8xxx_kp *kp = input_get_drvdata(dev);
return pmic8xxx_kp_enable(kp);
}
static void pmic8xxx_kp_close(struct input_dev *dev)
{
struct pmic8xxx_kp *kp = input_get_drvdata(dev);
pmic8xxx_kp_disable(kp);
}
/*
* keypad controller should be initialized in the following sequence
* only, otherwise it might get into FSM stuck state.
*
* - Initialize keypad control parameters, like no. of rows, columns,
* timing values etc.,
* - configure rows and column gpios pull up/down.
* - set irq edge type.
* - enable the keypad controller.
*/
static int pmic8xxx_kp_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
unsigned int rows, cols;
bool repeat;
bool wakeup;
struct pmic8xxx_kp *kp;
int rc;
unsigned int ctrl_val;
rc = matrix_keypad_parse_properties(&pdev->dev, &rows, &cols);
if (rc)
return rc;
if (cols > PM8XXX_MAX_COLS || rows > PM8XXX_MAX_ROWS ||
cols < PM8XXX_MIN_COLS) {
dev_err(&pdev->dev, "invalid platform data\n");
return -EINVAL;
}
repeat = !of_property_read_bool(np, "linux,input-no-autorepeat");
wakeup = of_property_read_bool(np, "wakeup-source") ||
/* legacy name */
of_property_read_bool(np, "linux,keypad-wakeup");
kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL);
if (!kp)
return -ENOMEM;
kp->regmap = dev_get_regmap(pdev->dev.parent, NULL);
if (!kp->regmap)
return -ENODEV;
platform_set_drvdata(pdev, kp);
kp->num_rows = rows;
kp->num_cols = cols;
kp->dev = &pdev->dev;
kp->input = devm_input_allocate_device(&pdev->dev);
if (!kp->input) {
dev_err(&pdev->dev, "unable to allocate input device\n");
return -ENOMEM;
}
kp->key_sense_irq = platform_get_irq(pdev, 0);
if (kp->key_sense_irq < 0)
return kp->key_sense_irq;
kp->key_stuck_irq = platform_get_irq(pdev, 1);
if (kp->key_stuck_irq < 0)
return kp->key_stuck_irq;
kp->input->name = "PMIC8XXX keypad";
kp->input->phys = "pmic8xxx_keypad/input0";
kp->input->id.bustype = BUS_I2C;
kp->input->id.version = 0x0001;
kp->input->id.product = 0x0001;
kp->input->id.vendor = 0x0001;
kp->input->open = pmic8xxx_kp_open;
kp->input->close = pmic8xxx_kp_close;
rc = matrix_keypad_build_keymap(NULL, NULL,
PM8XXX_MAX_ROWS, PM8XXX_MAX_COLS,
kp->keycodes, kp->input);
if (rc) {
dev_err(&pdev->dev, "failed to build keymap\n");
return rc;
}
if (repeat)
__set_bit(EV_REP, kp->input->evbit);
input_set_capability(kp->input, EV_MSC, MSC_SCAN);
input_set_drvdata(kp->input, kp);
/* initialize keypad state */
memset(kp->keystate, 0xff, sizeof(kp->keystate));
memset(kp->stuckstate, 0xff, sizeof(kp->stuckstate));
rc = pmic8xxx_kpd_init(kp, pdev);
if (rc < 0) {
dev_err(&pdev->dev, "unable to initialize keypad controller\n");
return rc;
}
rc = devm_request_any_context_irq(&pdev->dev, kp->key_sense_irq,
pmic8xxx_kp_irq, IRQF_TRIGGER_RISING, "pmic-keypad",
kp);
if (rc < 0) {
dev_err(&pdev->dev, "failed to request keypad sense irq\n");
return rc;
}
rc = devm_request_any_context_irq(&pdev->dev, kp->key_stuck_irq,
pmic8xxx_kp_stuck_irq, IRQF_TRIGGER_RISING,
"pmic-keypad-stuck", kp);
if (rc < 0) {
dev_err(&pdev->dev, "failed to request keypad stuck irq\n");
return rc;
}
rc = regmap_read(kp->regmap, KEYP_CTRL, &ctrl_val);
if (rc < 0) {
dev_err(&pdev->dev, "failed to read KEYP_CTRL register\n");
return rc;
}
kp->ctrl_reg = ctrl_val;
rc = input_register_device(kp->input);
if (rc < 0) {
dev_err(&pdev->dev, "unable to register keypad input device\n");
return rc;
}
device_init_wakeup(&pdev->dev, wakeup);
return 0;
}
static int pmic8xxx_kp_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct pmic8xxx_kp *kp = platform_get_drvdata(pdev);
struct input_dev *input_dev = kp->input;
if (device_may_wakeup(dev)) {
enable_irq_wake(kp->key_sense_irq);
} else {
mutex_lock(&input_dev->mutex);
if (input_device_enabled(input_dev))
pmic8xxx_kp_disable(kp);
mutex_unlock(&input_dev->mutex);
}
return 0;
}
static int pmic8xxx_kp_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct pmic8xxx_kp *kp = platform_get_drvdata(pdev);
struct input_dev *input_dev = kp->input;
if (device_may_wakeup(dev)) {
disable_irq_wake(kp->key_sense_irq);
} else {
mutex_lock(&input_dev->mutex);
if (input_device_enabled(input_dev))
pmic8xxx_kp_enable(kp);
mutex_unlock(&input_dev->mutex);
}
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(pm8xxx_kp_pm_ops,
pmic8xxx_kp_suspend, pmic8xxx_kp_resume);
static const struct of_device_id pm8xxx_match_table[] = {
{ .compatible = "qcom,pm8058-keypad" },
{ .compatible = "qcom,pm8921-keypad" },
{ }
};
MODULE_DEVICE_TABLE(of, pm8xxx_match_table);
static struct platform_driver pmic8xxx_kp_driver = {
.probe = pmic8xxx_kp_probe,
.driver = {
.name = "pm8xxx-keypad",
.pm = pm_sleep_ptr(&pm8xxx_kp_pm_ops),
.of_match_table = pm8xxx_match_table,
},
};
module_platform_driver(pmic8xxx_kp_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("PMIC8XXX keypad driver");
MODULE_ALIAS("platform:pmic8xxx_keypad");
MODULE_AUTHOR("Trilok Soni <[email protected]>");
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