587 lines
14 KiB
C
587 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* GPIO driven matrix keyboard driver
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*
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* Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
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*
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* Based on corgikbd.c
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*/
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#include <linux/types.h>
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#include <linux/delay.h>
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#include <linux/gpio/consumer.h>
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#include <linux/platform_device.h>
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#include <linux/input.h>
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#include <linux/irq.h>
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#include <linux/interrupt.h>
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#include <linux/jiffies.h>
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#include <linux/module.h>
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#include <linux/gpio.h>
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#include <linux/input/matrix_keypad.h>
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#include <linux/slab.h>
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#include <linux/of.h>
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#include <linux/of_gpio.h>
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#include <linux/of_platform.h>
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struct matrix_keypad {
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const struct matrix_keypad_platform_data *pdata;
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struct input_dev *input_dev;
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unsigned int row_shift;
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DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
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uint32_t last_key_state[MATRIX_MAX_COLS];
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struct delayed_work work;
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spinlock_t lock;
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bool scan_pending;
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bool stopped;
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bool gpio_all_disabled;
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};
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/*
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* NOTE: If drive_inactive_cols is false, then the GPIO has to be put into
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* HiZ when de-activated to cause minmal side effect when scanning other
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* columns. In that case it is configured here to be input, otherwise it is
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* driven with the inactive value.
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*/
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static void __activate_col(const struct matrix_keypad_platform_data *pdata,
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int col, bool on)
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{
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bool level_on = !pdata->active_low;
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if (on) {
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gpio_direction_output(pdata->col_gpios[col], level_on);
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} else {
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gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
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if (!pdata->drive_inactive_cols)
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gpio_direction_input(pdata->col_gpios[col]);
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}
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}
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static void activate_col(const struct matrix_keypad_platform_data *pdata,
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int col, bool on)
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{
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__activate_col(pdata, col, on);
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if (on && pdata->col_scan_delay_us)
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udelay(pdata->col_scan_delay_us);
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}
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static void activate_all_cols(const struct matrix_keypad_platform_data *pdata,
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bool on)
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{
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int col;
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for (col = 0; col < pdata->num_col_gpios; col++)
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__activate_col(pdata, col, on);
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}
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static bool row_asserted(const struct matrix_keypad_platform_data *pdata,
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int row)
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{
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return gpio_get_value_cansleep(pdata->row_gpios[row]) ?
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!pdata->active_low : pdata->active_low;
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}
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static void enable_row_irqs(struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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int i;
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if (pdata->clustered_irq > 0)
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enable_irq(pdata->clustered_irq);
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else {
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for (i = 0; i < pdata->num_row_gpios; i++)
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enable_irq(gpio_to_irq(pdata->row_gpios[i]));
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}
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}
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static void disable_row_irqs(struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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int i;
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if (pdata->clustered_irq > 0)
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disable_irq_nosync(pdata->clustered_irq);
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else {
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for (i = 0; i < pdata->num_row_gpios; i++)
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disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
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}
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}
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/*
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* This gets the keys from keyboard and reports it to input subsystem
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*/
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static void matrix_keypad_scan(struct work_struct *work)
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{
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struct matrix_keypad *keypad =
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container_of(work, struct matrix_keypad, work.work);
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struct input_dev *input_dev = keypad->input_dev;
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const unsigned short *keycodes = input_dev->keycode;
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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uint32_t new_state[MATRIX_MAX_COLS];
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int row, col, code;
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/* de-activate all columns for scanning */
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activate_all_cols(pdata, false);
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memset(new_state, 0, sizeof(new_state));
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/* assert each column and read the row status out */
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for (col = 0; col < pdata->num_col_gpios; col++) {
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activate_col(pdata, col, true);
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for (row = 0; row < pdata->num_row_gpios; row++)
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new_state[col] |=
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row_asserted(pdata, row) ? (1 << row) : 0;
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activate_col(pdata, col, false);
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}
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for (col = 0; col < pdata->num_col_gpios; col++) {
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uint32_t bits_changed;
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bits_changed = keypad->last_key_state[col] ^ new_state[col];
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if (bits_changed == 0)
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continue;
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for (row = 0; row < pdata->num_row_gpios; row++) {
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if ((bits_changed & (1 << row)) == 0)
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continue;
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code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
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input_event(input_dev, EV_MSC, MSC_SCAN, code);
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input_report_key(input_dev,
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keycodes[code],
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new_state[col] & (1 << row));
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}
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}
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input_sync(input_dev);
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memcpy(keypad->last_key_state, new_state, sizeof(new_state));
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activate_all_cols(pdata, true);
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/* Enable IRQs again */
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spin_lock_irq(&keypad->lock);
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keypad->scan_pending = false;
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enable_row_irqs(keypad);
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spin_unlock_irq(&keypad->lock);
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}
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static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
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{
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struct matrix_keypad *keypad = id;
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unsigned long flags;
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spin_lock_irqsave(&keypad->lock, flags);
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/*
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* See if another IRQ beaten us to it and scheduled the
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* scan already. In that case we should not try to
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* disable IRQs again.
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*/
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if (unlikely(keypad->scan_pending || keypad->stopped))
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goto out;
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disable_row_irqs(keypad);
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keypad->scan_pending = true;
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schedule_delayed_work(&keypad->work,
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msecs_to_jiffies(keypad->pdata->debounce_ms));
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out:
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spin_unlock_irqrestore(&keypad->lock, flags);
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return IRQ_HANDLED;
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}
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static int matrix_keypad_start(struct input_dev *dev)
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{
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struct matrix_keypad *keypad = input_get_drvdata(dev);
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keypad->stopped = false;
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mb();
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/*
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* Schedule an immediate key scan to capture current key state;
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* columns will be activated and IRQs be enabled after the scan.
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*/
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schedule_delayed_work(&keypad->work, 0);
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return 0;
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}
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static void matrix_keypad_stop(struct input_dev *dev)
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{
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struct matrix_keypad *keypad = input_get_drvdata(dev);
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spin_lock_irq(&keypad->lock);
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keypad->stopped = true;
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spin_unlock_irq(&keypad->lock);
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flush_delayed_work(&keypad->work);
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/*
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* matrix_keypad_scan() will leave IRQs enabled;
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* we should disable them now.
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*/
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disable_row_irqs(keypad);
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}
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#ifdef CONFIG_PM_SLEEP
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static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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unsigned int gpio;
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int i;
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if (pdata->clustered_irq > 0) {
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if (enable_irq_wake(pdata->clustered_irq) == 0)
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keypad->gpio_all_disabled = true;
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} else {
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for (i = 0; i < pdata->num_row_gpios; i++) {
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if (!test_bit(i, keypad->disabled_gpios)) {
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gpio = pdata->row_gpios[i];
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if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
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__set_bit(i, keypad->disabled_gpios);
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}
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}
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}
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}
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static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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unsigned int gpio;
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int i;
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if (pdata->clustered_irq > 0) {
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if (keypad->gpio_all_disabled) {
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disable_irq_wake(pdata->clustered_irq);
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keypad->gpio_all_disabled = false;
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}
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} else {
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for (i = 0; i < pdata->num_row_gpios; i++) {
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if (test_and_clear_bit(i, keypad->disabled_gpios)) {
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gpio = pdata->row_gpios[i];
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disable_irq_wake(gpio_to_irq(gpio));
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}
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}
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}
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}
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static int matrix_keypad_suspend(struct device *dev)
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{
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struct platform_device *pdev = to_platform_device(dev);
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struct matrix_keypad *keypad = platform_get_drvdata(pdev);
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matrix_keypad_stop(keypad->input_dev);
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if (device_may_wakeup(&pdev->dev))
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matrix_keypad_enable_wakeup(keypad);
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return 0;
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}
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static int matrix_keypad_resume(struct device *dev)
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{
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struct platform_device *pdev = to_platform_device(dev);
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struct matrix_keypad *keypad = platform_get_drvdata(pdev);
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if (device_may_wakeup(&pdev->dev))
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matrix_keypad_disable_wakeup(keypad);
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matrix_keypad_start(keypad->input_dev);
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return 0;
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}
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#endif
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static SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
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matrix_keypad_suspend, matrix_keypad_resume);
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static int matrix_keypad_init_gpio(struct platform_device *pdev,
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struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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int i, err;
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/* initialized strobe lines as outputs, activated */
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for (i = 0; i < pdata->num_col_gpios; i++) {
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err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
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if (err) {
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dev_err(&pdev->dev,
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"failed to request GPIO%d for COL%d\n",
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pdata->col_gpios[i], i);
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goto err_free_cols;
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}
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gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
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}
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for (i = 0; i < pdata->num_row_gpios; i++) {
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err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
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if (err) {
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dev_err(&pdev->dev,
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"failed to request GPIO%d for ROW%d\n",
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pdata->row_gpios[i], i);
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goto err_free_rows;
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}
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gpio_direction_input(pdata->row_gpios[i]);
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}
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if (pdata->clustered_irq > 0) {
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err = request_any_context_irq(pdata->clustered_irq,
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matrix_keypad_interrupt,
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pdata->clustered_irq_flags,
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"matrix-keypad", keypad);
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if (err < 0) {
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dev_err(&pdev->dev,
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"Unable to acquire clustered interrupt\n");
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goto err_free_rows;
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}
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} else {
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for (i = 0; i < pdata->num_row_gpios; i++) {
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err = request_any_context_irq(
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gpio_to_irq(pdata->row_gpios[i]),
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matrix_keypad_interrupt,
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IRQF_TRIGGER_RISING |
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IRQF_TRIGGER_FALLING,
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"matrix-keypad", keypad);
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if (err < 0) {
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dev_err(&pdev->dev,
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"Unable to acquire interrupt for GPIO line %i\n",
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pdata->row_gpios[i]);
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goto err_free_irqs;
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}
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}
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}
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/* initialized as disabled - enabled by input->open */
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disable_row_irqs(keypad);
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return 0;
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err_free_irqs:
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while (--i >= 0)
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free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
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i = pdata->num_row_gpios;
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err_free_rows:
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while (--i >= 0)
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gpio_free(pdata->row_gpios[i]);
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i = pdata->num_col_gpios;
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err_free_cols:
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while (--i >= 0)
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gpio_free(pdata->col_gpios[i]);
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return err;
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}
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static void matrix_keypad_free_gpio(struct matrix_keypad *keypad)
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{
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const struct matrix_keypad_platform_data *pdata = keypad->pdata;
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int i;
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if (pdata->clustered_irq > 0) {
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free_irq(pdata->clustered_irq, keypad);
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} else {
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for (i = 0; i < pdata->num_row_gpios; i++)
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free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
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}
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for (i = 0; i < pdata->num_row_gpios; i++)
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gpio_free(pdata->row_gpios[i]);
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for (i = 0; i < pdata->num_col_gpios; i++)
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gpio_free(pdata->col_gpios[i]);
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}
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#ifdef CONFIG_OF
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static struct matrix_keypad_platform_data *
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matrix_keypad_parse_dt(struct device *dev)
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{
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struct matrix_keypad_platform_data *pdata;
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struct device_node *np = dev->of_node;
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unsigned int *gpios;
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int ret, i, nrow, ncol;
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if (!np) {
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dev_err(dev, "device lacks DT data\n");
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return ERR_PTR(-ENODEV);
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}
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pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
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if (!pdata) {
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dev_err(dev, "could not allocate memory for platform data\n");
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return ERR_PTR(-ENOMEM);
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}
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pdata->num_row_gpios = nrow = gpiod_count(dev, "row");
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pdata->num_col_gpios = ncol = gpiod_count(dev, "col");
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if (nrow < 0 || ncol < 0) {
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dev_err(dev, "number of keypad rows/columns not specified\n");
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return ERR_PTR(-EINVAL);
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}
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if (of_get_property(np, "linux,no-autorepeat", NULL))
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pdata->no_autorepeat = true;
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pdata->wakeup = of_property_read_bool(np, "wakeup-source") ||
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of_property_read_bool(np, "linux,wakeup"); /* legacy */
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if (of_get_property(np, "gpio-activelow", NULL))
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pdata->active_low = true;
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pdata->drive_inactive_cols =
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of_property_read_bool(np, "drive-inactive-cols");
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of_property_read_u32(np, "debounce-delay-ms", &pdata->debounce_ms);
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of_property_read_u32(np, "col-scan-delay-us",
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&pdata->col_scan_delay_us);
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gpios = devm_kcalloc(dev,
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pdata->num_row_gpios + pdata->num_col_gpios,
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sizeof(unsigned int),
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GFP_KERNEL);
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if (!gpios) {
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dev_err(dev, "could not allocate memory for gpios\n");
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return ERR_PTR(-ENOMEM);
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}
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for (i = 0; i < nrow; i++) {
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ret = of_get_named_gpio(np, "row-gpios", i);
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if (ret < 0)
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return ERR_PTR(ret);
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gpios[i] = ret;
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}
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for (i = 0; i < ncol; i++) {
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ret = of_get_named_gpio(np, "col-gpios", i);
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if (ret < 0)
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return ERR_PTR(ret);
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gpios[nrow + i] = ret;
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}
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pdata->row_gpios = gpios;
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pdata->col_gpios = &gpios[pdata->num_row_gpios];
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return pdata;
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}
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#else
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static inline struct matrix_keypad_platform_data *
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matrix_keypad_parse_dt(struct device *dev)
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{
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dev_err(dev, "no platform data defined\n");
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return ERR_PTR(-EINVAL);
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}
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#endif
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static int matrix_keypad_probe(struct platform_device *pdev)
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{
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const struct matrix_keypad_platform_data *pdata;
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struct matrix_keypad *keypad;
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struct input_dev *input_dev;
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int err;
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pdata = dev_get_platdata(&pdev->dev);
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if (!pdata) {
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pdata = matrix_keypad_parse_dt(&pdev->dev);
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if (IS_ERR(pdata))
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return PTR_ERR(pdata);
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} else if (!pdata->keymap_data) {
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dev_err(&pdev->dev, "no keymap data defined\n");
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return -EINVAL;
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}
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keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
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input_dev = input_allocate_device();
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if (!keypad || !input_dev) {
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err = -ENOMEM;
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goto err_free_mem;
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}
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keypad->input_dev = input_dev;
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keypad->pdata = pdata;
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keypad->row_shift = get_count_order(pdata->num_col_gpios);
|
|
keypad->stopped = true;
|
|
INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
|
|
spin_lock_init(&keypad->lock);
|
|
|
|
input_dev->name = pdev->name;
|
|
input_dev->id.bustype = BUS_HOST;
|
|
input_dev->dev.parent = &pdev->dev;
|
|
input_dev->open = matrix_keypad_start;
|
|
input_dev->close = matrix_keypad_stop;
|
|
|
|
err = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
|
|
pdata->num_row_gpios,
|
|
pdata->num_col_gpios,
|
|
NULL, input_dev);
|
|
if (err) {
|
|
dev_err(&pdev->dev, "failed to build keymap\n");
|
|
goto err_free_mem;
|
|
}
|
|
|
|
if (!pdata->no_autorepeat)
|
|
__set_bit(EV_REP, input_dev->evbit);
|
|
input_set_capability(input_dev, EV_MSC, MSC_SCAN);
|
|
input_set_drvdata(input_dev, keypad);
|
|
|
|
err = matrix_keypad_init_gpio(pdev, keypad);
|
|
if (err)
|
|
goto err_free_mem;
|
|
|
|
err = input_register_device(keypad->input_dev);
|
|
if (err)
|
|
goto err_free_gpio;
|
|
|
|
device_init_wakeup(&pdev->dev, pdata->wakeup);
|
|
platform_set_drvdata(pdev, keypad);
|
|
|
|
return 0;
|
|
|
|
err_free_gpio:
|
|
matrix_keypad_free_gpio(keypad);
|
|
err_free_mem:
|
|
input_free_device(input_dev);
|
|
kfree(keypad);
|
|
return err;
|
|
}
|
|
|
|
static int matrix_keypad_remove(struct platform_device *pdev)
|
|
{
|
|
struct matrix_keypad *keypad = platform_get_drvdata(pdev);
|
|
|
|
matrix_keypad_free_gpio(keypad);
|
|
input_unregister_device(keypad->input_dev);
|
|
kfree(keypad);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id matrix_keypad_dt_match[] = {
|
|
{ .compatible = "gpio-matrix-keypad" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, matrix_keypad_dt_match);
|
|
#endif
|
|
|
|
static struct platform_driver matrix_keypad_driver = {
|
|
.probe = matrix_keypad_probe,
|
|
.remove = matrix_keypad_remove,
|
|
.driver = {
|
|
.name = "matrix-keypad",
|
|
.pm = &matrix_keypad_pm_ops,
|
|
.of_match_table = of_match_ptr(matrix_keypad_dt_match),
|
|
},
|
|
};
|
|
module_platform_driver(matrix_keypad_driver);
|
|
|
|
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
|
|
MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_ALIAS("platform:matrix-keypad");
|