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Diffstat (limited to 'libsensors/gp2a_light.c')
-rw-r--r--libsensors/gp2a_light.c113
1 files changed, 55 insertions, 58 deletions
diff --git a/libsensors/gp2a_light.c b/libsensors/gp2a_light.c
index 9f2d37e..3a41187 100644
--- a/libsensors/gp2a_light.c
+++ b/libsensors/gp2a_light.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2013 Paul Kocialkowski
+ * Copyright (C) 2013 Paul Kocialkowski <contact@paulk.fr>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -21,6 +21,7 @@
#include <fcntl.h>
#include <errno.h>
#include <math.h>
+#include <sys/types.h>
#include <linux/ioctl.h>
#include <linux/input.h>
@@ -37,7 +38,8 @@ struct gp2a_light_data {
char path_delay[PATH_MAX];
};
-int gp2a_light_init(struct piranha_sensors_handlers *handlers, struct piranha_sensors_device *device)
+int gp2a_light_init(struct piranha_sensors_handlers *handlers,
+ struct piranha_sensors_device *device)
{
struct gp2a_light_data *data = NULL;
char path[PATH_MAX] = { 0 };
@@ -49,6 +51,8 @@ int gp2a_light_init(struct piranha_sensors_handlers *handlers, struct piranha_se
if (handlers == NULL)
return -EINVAL;
+ data = (struct gp2a_light_data *) calloc(1, sizeof(struct gp2a_light_data));
+
input_fd = input_open("light_sensor");
if (input_fd < 0) {
ALOGE("%s: Unable to open input", __func__);
@@ -61,8 +65,6 @@ int gp2a_light_init(struct piranha_sensors_handlers *handlers, struct piranha_se
goto error;
}
- data = (struct gp2a_light_data *) calloc(1, sizeof(struct gp2a_light_data));
-
snprintf(data->path_enable, PATH_MAX, "%s/enable", path);
snprintf(data->path_delay, PATH_MAX, "%s/poll_delay", path);
@@ -72,12 +74,12 @@ int gp2a_light_init(struct piranha_sensors_handlers *handlers, struct piranha_se
return 0;
error:
- if (input_fd >= 0)
- close(input_fd);
-
if (data != NULL)
free(data);
+ if (input_fd >= 0)
+ close(input_fd);
+
handlers->poll_fd = -1;
handlers->data = NULL;
@@ -86,22 +88,17 @@ error:
int gp2a_light_deinit(struct piranha_sensors_handlers *handlers)
{
- int input_fd;
-
ALOGD("%s(%p)", __func__, handlers);
if (handlers == NULL)
return -EINVAL;
- input_fd = handlers->poll_fd;
- if (input_fd >= 0)
- close(input_fd);
-
+ if (handlers->poll_fd >= 0)
+ close(handlers->poll_fd);
handlers->poll_fd = -1;
if (handlers->data != NULL)
free(handlers->data);
-
handlers->data = NULL;
return 0;
@@ -110,8 +107,7 @@ int gp2a_light_deinit(struct piranha_sensors_handlers *handlers)
int gp2a_light_activate(struct piranha_sensors_handlers *handlers)
{
struct gp2a_light_data *data;
- char enable[] = "1\n";
- int fd;
+ int rc;
ALOGD("%s(%p)", __func__, handlers);
@@ -120,15 +116,12 @@ int gp2a_light_activate(struct piranha_sensors_handlers *handlers)
data = (struct gp2a_light_data *) handlers->data;
- fd = open(data->path_enable, O_WRONLY);
- if (fd < 0) {
- ALOGE("%s: Unable to open enable path", __func__);
+ rc = sysfs_value_write(data->path_enable, 1);
+ if (rc < 0) {
+ ALOGE("%s: Unable to write sysfs value", __func__);
return -1;
}
- write(fd, &enable, sizeof(enable));
- close(fd);
-
handlers->activated = 1;
return 0;
@@ -137,8 +130,7 @@ int gp2a_light_activate(struct piranha_sensors_handlers *handlers)
int gp2a_light_deactivate(struct piranha_sensors_handlers *handlers)
{
struct gp2a_light_data *data;
- char enable[] = "0\n";
- int fd;
+ int rc;
ALOGD("%s(%p)", __func__, handlers);
@@ -147,54 +139,50 @@ int gp2a_light_deactivate(struct piranha_sensors_handlers *handlers)
data = (struct gp2a_light_data *) handlers->data;
- fd = open(data->path_enable, O_WRONLY);
- if (fd < 0) {
- ALOGE("%s: Unable to open enable path", __func__);
+ rc = sysfs_value_write(data->path_enable, 0);
+ if (rc < 0) {
+ ALOGE("%s: Unable to write sysfs value", __func__);
return -1;
}
- write(fd, &enable, sizeof(enable));
- close(fd);
-
- handlers->activated = 0;
+ handlers->activated = 1;
return 0;
}
-int gp2a_light_set_delay(struct piranha_sensors_handlers *handlers, int64_t delay)
+int gp2a_light_set_delay(struct piranha_sensors_handlers *handlers, long int delay)
{
struct gp2a_light_data *data;
- char *value = NULL;
- int c;
- int fd;
+ int rc;
-// ALOGD("%s(%p, %ld)", __func__, handlers, (long int) delay);
+ ALOGD("%s(%p, %ld)", __func__, handlers, delay);
if (handlers == NULL || handlers->data == NULL)
return -EINVAL;
data = (struct gp2a_light_data *) handlers->data;
- c = asprintf(&value, "%ld\n", (long int) delay);
-
- fd = open(data->path_delay, O_WRONLY);
- if (fd < 0) {
- ALOGE("%s: Unable to open delay path", __func__);
+ rc = sysfs_value_write(data->path_delay, (int) delay);
+ if (rc < 0) {
+ ALOGE("%s: Unable to write sysfs value", __func__);
return -1;
}
- write(fd, value, c);
- close(fd);
-
- if (value != NULL)
- free(value);
-
return 0;
}
-float gp2a_light_light(int value)
+float gp2a_light_convert(int value)
{
- return (float) powf(10, value * (125.0f / 1023.0f / 24.0f)) * 4;
+ // Converting the raw value to lux units is done with:
+ // I = 10 * log(light) uA
+ // U = raw * 3300 / 4095 (max ADC value is 3.3V for 4095 LSB)
+ // R = 47kOhm
+ // => light = 10 ^ (I / 10) = 10 ^ (U / R / 10)
+ // => light = 10 ^ (raw * 330 / 4095 / 47)
+ // Only 1/4 of light reaches the sensor:
+ // => light = 4 * (10 ^ (raw * 330 / 4095 / 47))
+
+ return powf(10, value * (330.0f / 4095.0f / 47.0f)) * 4;
}
int gp2a_light_get_data(struct piranha_sensors_handlers *handlers,
@@ -204,6 +192,8 @@ int gp2a_light_get_data(struct piranha_sensors_handlers *handlers,
int input_fd;
int rc;
+// ALOGD("%s(%p, %p)", __func__, handlers, event);
+
if (handlers == NULL || event == NULL)
return -EINVAL;
@@ -211,18 +201,24 @@ int gp2a_light_get_data(struct piranha_sensors_handlers *handlers,
if (input_fd < 0)
return -EINVAL;
- rc = read(input_fd, &input_event, sizeof(input_event));
- if (rc < (int) sizeof(input_event))
- return -EINVAL;
-
- if (input_event.type != EV_ABS || input_event.code != ABS_MISC)
- return -1;
-
+ memset(event, 0, sizeof(struct sensors_event_t));
event->version = sizeof(struct sensors_event_t);
event->sensor = handlers->handle;
event->type = handlers->handle;
- event->timestamp = input_timestamp(&input_event);
- event->light = gp2a_light_light(input_event.value);
+
+ do {
+ rc = read(input_fd, &input_event, sizeof(input_event));
+ if (rc < (int) sizeof(input_event))
+ break;
+
+ if (input_event.type == EV_REL) {
+ if (input_event.code == REL_MISC)
+ event->light = gp2a_light_convert(input_event.value);
+ } else if (input_event.type == EV_SYN) {
+ if (input_event.code == SYN_REPORT)
+ event->timestamp = input_timestamp(&input_event);
+ }
+ } while (input_event.type != EV_SYN);
return 0;
}
@@ -237,6 +233,7 @@ struct piranha_sensors_handlers gp2a_light = {
.set_delay = gp2a_light_set_delay,
.get_data = gp2a_light_get_data,
.activated = 0,
+ .needed = 0,
.poll_fd = -1,
.data = NULL,
};
generated by cgit v1.1 at 2024-05-19 15:17:39 +0000