Files
OpenCellular/common/als.c
Bill Richardson 43806f07e3 samus: Add scale factor to account for ALS attenuation
This adds a sensor-specific attentuation factor, which will be
applied to the ALS raw sensor readings on the EC. This is to
account for the attenutation due to glass, tinting, etc.

BUG=chrome-os-partner:34590
BRANCH=ToT,Samus
TEST=manual

In a root shell, run this:

  cd /sys/bus/acpi/drivers/acpi_als/ACPI0008:00/iio:device1
  while true; do cat in_illuminance_raw; sleep 1 ;done

Shine a flashlight on the ALS. Note that the readings are 5X
higher than they were before this CL.

Change-Id: I2a53872ecb5fab62e5f443d43588a26d3d7e697f
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/241191
Reviewed-by: Bryan Freed <bfreed@chromium.org>
2015-01-21 05:05:47 +00:00

62 lines
1.3 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);
while (1) {
for (i = 0; i < EC_ALS_ENTRIES && i < ALS_COUNT; i++)
mapped[i] = als_read(i, &val) == EC_SUCCESS ? val : 0;
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);