coreboot-libre-fam15h-rdimm/3rdparty/chromeec/common/capsense.c

86 lines
2.0 KiB
C

/* Copyright 2014 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "common.h"
#include "console.h"
#include "gpio.h"
#include "hooks.h"
#include "i2c.h"
#include "keyboard_protocol.h"
#include "timer.h"
/* Console output macro */
#define CPRINTF(format, args...) cprintf(CC_KEYBOARD, format, ## args)
#define CPRINTS(format, args...) cprints(CC_KEYBOARD, format, ## args)
#define CAPSENSE_I2C_ADDR 0x08
#define CAPSENSE_MASK_BITS 8
#define CAPSENSE_POLL_INTERVAL (20 * MSEC)
static int capsense_read_bitmask(void)
{
int rv;
uint8_t val = 0;
rv = i2c_xfer(I2C_PORT_CAPSENSE, CAPSENSE_I2C_ADDR,
0, 0, &val, 1);
if (rv)
CPRINTS("%s failed: error %d", __func__, rv);
return val;
}
static void capsense_init(void)
{
gpio_enable_interrupt(GPIO_CAPSENSE_INT_L);
}
DECLARE_HOOK(HOOK_INIT, capsense_init, HOOK_PRIO_DEFAULT);
/*
* Keep checking polling the capsense until all the buttons are released.
* We're not worrying about debouncing, since the capsense module should do
* that for us.
*/
static void capsense_change_deferred(void)
{
static uint8_t cur_val;
uint8_t new_val;
int i, n, c;
new_val = capsense_read_bitmask();
if (new_val != cur_val) {
CPRINTF("[%T capsense 0x%02x: ", new_val);
for (i = 0; i < CAPSENSE_MASK_BITS; i++) {
/* See what changed */
n = (new_val >> i) & 0x01;
c = (cur_val >> i) & 0x01;
CPRINTF("%s", n ? " X " : " _ ");
if (n == c)
continue;
#ifdef HAS_TASK_KEYPROTO
/* Treat it as a keyboard event. */
keyboard_update_button(i + KEYBOARD_BUTTON_CAPSENSE_1,
n);
#endif
}
CPRINTF("]\n");
cur_val = new_val;
}
if (cur_val)
hook_call_deferred(&capsense_change_deferred_data,
CAPSENSE_POLL_INTERVAL);
}
DECLARE_DEFERRED(capsense_change_deferred);
/*
* Somebody's poking at us.
*/
void capsense_interrupt(enum gpio_signal signal)
{
hook_call_deferred(&capsense_change_deferred_data, 0);
}