misc: apds990x_als: added apds990x proximity test

apds990x is a combined proximity/als sensor. The test provides a
basic test for the als part.

The following are the testing steps:

- power on the sensor
- read 10 times the lux value on 1 second interval

Signed-off-by: Andi Shyti <andi@etezian.org>

1 files changed, 153 insertions, 0 deletions

diff --git a/drivers/misc/apds990x_als.c b/drivers/misc/apds990x_als.c
new file mode 100644
index 0000000..abad5e8
--- /dev/null
+++ b/drivers/misc/apds990x_als.c
@@ -0,0 +1,153 @@
+/*
+ * apds990x ambient light sensor testing module
+ * Copyright (C) 2013  Andi Shyti <andi@etezian.org>
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#define MAX_N	100
+#define ENABLE	"1"
+#define DISABLE	"0"
+
+struct device {
+	unsigned int n;
+
+	char *power;
+	char *als_raw;
+};
+
+struct device apds990x_dev = {
+	.n = 10,
+	.power = "/sys/class/i2c-adapter/i2c-0012/12-0039/power_state",
+	.als_raw = "/sys/class/i2c-adapter/i2c-0012/12-0039/lux0_raw",
+};
+
+int write_file(char *fname, const char *val)
+{
+	int fd;
+	ssize_t ret;
+
+	fd = open(fname, O_WRONLY);
+	if (fd < 0) {
+		fprintf(stderr, "%s: %s\n", fname, strerror(errno));
+		return errno;
+	}
+
+	ret = write(fd, val, 1);
+	if (ret != 1) {
+		fprintf(stderr, "%s: %s\n", fname, strerror(errno));
+		close(fd);
+		return errno;
+	}
+
+	fd = close(fd);
+	if (fd < 0)
+		fprintf(stderr, "%s: %s\n", fname, strerror(errno));
+
+	return errno;
+}
+
+int read_als(void)
+{
+	int i, fd;
+	ssize_t ret;
+	char val[6];
+
+	fd = open(apds990x_dev.als_raw, O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "%s: %s\n", apds990x_dev.als_raw,
+							strerror(errno));
+		return errno;
+	}
+
+	for (i = 0; i < apds990x_dev.n; i++) {
+		ret = read(fd, val, 5);
+		if (!ret) {
+			fprintf(stderr, "%s: %s\n",
+				apds990x_dev.als_raw, strerror(errno));
+			break;
+		}
+
+		val[ret] = '\0';
+		printf("%s\n", val);
+		sleep(1);
+	}
+
+	return errno;
+}
+
+void print_usage(char *name)
+{
+	printf("Usage: %s [-n <number>]\n", name);
+	printf("\n");
+	printf("	-n <number>	- number of readings on the device\n");
+	printf("	-h, --help	- print help menu\n");
+}
+
+int parse_cmdline(int argc, char *argv[])
+{
+	int i;
+	unsigned long int n;
+
+	for (i = 1; i < argc; i++) {
+		if (!strcmp(argv[i], "-n")) {
+			n = strtoul(argv[++i], NULL, 10);
+			/* check for overflow */
+			if (errno)
+				return errno;
+
+			apds990x_dev.n = ((n > MAX_N) || (n <= 0)) ?
+						MAX_N : (unsigned int) n;
+		} else if (!strcmp(argv[i], "-h") ||
+						!strcmp(argv[i], "--help")) {
+			print_usage(argv[0]);
+			exit(EXIT_SUCCESS);
+		} else {
+			fprintf(stderr, "%s: %s\n\n",
+						argv[i], strerror(EINVAL));
+			print_usage(argv[0]);
+			return EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int err;
+
+	if (argc > 1) {
+		err = parse_cmdline(argc, argv);
+		if (err)
+			return err;
+	}
+
+	err = write_file(apds990x_dev.power, ENABLE);
+	if (err)
+		return err;
+
+	read_als();
+	err = write_file(apds990x_dev.power, DISABLE);
+
+	return err;
+}