Files
OpenCellular/common/als.c
Shawn Nematbakhsh 6ee7b1e34e ACPI: Support accessing memmap data over ACPI CMD / DATA ports
Some platforms are unable to access the 900h-9ffh region over LPC and
must instead access memmap data through the ACPI CMD / DATA ports. To
avoid racing with data updates, disallow changes to multi-byte memmap
data while in burst mode.

Linux currently enables burst mode when accessing multi-byte data and
disables it immediately afterward, though the ACPI spec defines burst mode
in a more general way.

BUG=chrome-os-partner:38224
TEST=Manual on Samus. Undefine LPC_MEMMAP and modify asl to move memmap
data to ERAM at offset 0x20. Verify system boots cleanly and battery
status is updated immediately on plug / unplug.
BRANCH=None

Change-Id: Ib848bdb491fdfece96ad0cee7a44ba85b4a1a50b
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/262072
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
2015-03-25 20:09:52 +00:00

67 lines
1.4 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.
*/
/* This provides the interface for any Ambient Light Sensors that are connected
* to the EC instead of the AP.
*/
#include "als.h"
#include "common.h"
#include "console.h"
#include "host_command.h"
#include "task.h"
#include "timer.h"
#include "util.h"
int als_read(enum als_id id, int *lux)
{
int af = als[id].attenuation_factor;
return als[id].read(lux, af);
}
void als_task(void)
{
int i, val;
uint16_t *mapped = (uint16_t *)host_get_memmap(EC_MEMMAP_ALS);
uint16_t als_data;
while (1) {
for (i = 0; i < EC_ALS_ENTRIES && i < ALS_COUNT; i++) {
als_data = als_read(i, &val) == EC_SUCCESS ? val : 0;
host_lock_memmap();
mapped[i] = als_data;
host_unlock_memmap();
}
task_wait_event(SECOND);
}
}
/*****************************************************************************/
/* Console commands */
static int command_als(int argc, char **argv)
{
int i, rv, val;
for (i = 0; i < ALS_COUNT; i++) {
ccprintf("%s: ", als[i].name);
rv = als_read(i, &val);
switch (rv) {
case EC_SUCCESS:
ccprintf("%d lux\n", val);
break;
default:
ccprintf("Error %d\n", rv);
}
}
return EC_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(als, command_als,
NULL,
"Print ALS values",
NULL);