Files
OpenCellular/common/backlight_lid.c
Randall Spangler 84ba188120 Support backlight control via lid only
The old backlight_x86 code did

  (backlight enable) = (lid is open) && (GPIO request from AP)

Newer systems will AND those signals in hardware.  Support those
systems by separating CONFIG_BACKLIGHT_LID and
CONFIG_BACKLIGHT_REQ_GPIO, and add tests for the case where the enable
signal is dependent only on the lid position.

BUG=chrome-os-partner:22960
BRANCH=none
TEST=pass unit tests

Change-Id: I1909426e49f00a8acd5047fd88c801cba1dacd76
Reviewed-on: https://chromium-review.googlesource.com/170925
Tested-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Commit-Queue: Randall Spangler <rspangler@chromium.org>
2013-09-27 23:07:21 +00:00

72 lines
1.7 KiB
C

/* Copyright (c) 2013 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.
*/
/* Backlight control based on lid and optional request signal from AP */
#include "common.h"
#include "gpio.h"
#include "hooks.h"
#include "host_command.h"
#include "lid_switch.h"
/**
* Update backlight state.
*/
static void update_backlight(void)
{
#ifdef CONFIG_BACKLIGHT_REQ_GPIO
/* Enable the backlight if lid is open AND requested by AP */
gpio_set_level(GPIO_ENABLE_BACKLIGHT, lid_is_open() &&
gpio_get_level(CONFIG_BACKLIGHT_REQ_GPIO));
#else
/*
* Enable backlight if lid is open; this is AND'd with the request from
* the AP in hardware.
*/
gpio_set_level(GPIO_ENABLE_BACKLIGHT, lid_is_open());
#endif
}
DECLARE_HOOK(HOOK_LID_CHANGE, update_backlight, HOOK_PRIO_DEFAULT);
/**
* Initialize backlight module.
*/
static void backlight_init(void)
{
update_backlight();
#ifdef CONFIG_BACKLIGHT_REQ_GPIO
gpio_enable_interrupt(CONFIG_BACKLIGHT_REQ_GPIO);
#endif
}
DECLARE_HOOK(HOOK_INIT, backlight_init, HOOK_PRIO_DEFAULT);
#ifdef CONFIG_BACKLIGHT_REQ_GPIO
void backlight_interrupt(enum gpio_signal signal)
{
update_backlight();
}
#endif
/**
* Host command to toggle backlight.
*
* The requested state will persist until the next lid-switch or request-gpio
* transition.
*/
static int switch_command_enable_backlight(struct host_cmd_handler_args *args)
{
const struct ec_params_switch_enable_backlight *p = args->params;
gpio_set_level(GPIO_ENABLE_BACKLIGHT, p->enabled);
return EC_RES_SUCCESS;
}
DECLARE_HOST_COMMAND(EC_CMD_SWITCH_ENABLE_BKLIGHT,
switch_command_enable_backlight,
EC_VER_MASK(0));