Add ALS driver for light sensors connected to EC

This adds the driver and a console command to read an Intersil ISL29305
light sensor connected to the EC.

BUG=chrome-os-partner:23380
BRANCH=samus
TEST=manual

Run the "als" command from the EC console, while pointing the sensor in
various directions. It should give higher numbers when facing a light
source.  If you get "Error 1", it means the ALS isn't powered.

Change-Id: I855ed64dab7fc60e29126ab3e97669be24dc6a64
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/176056

1 files changed, 32 insertions, 0 deletions

diff --git a/include/als.h b/include/als.h
new file mode 100644
index 0000000000..e229a3791f
--- /dev/null
+++ b/include/als.h
@@ -0,0 +1,32 @@
+/* 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.
+ */
+
+#ifndef __CROS_EC_ALS_H
+#define __CROS_EC_ALS_H
+
+#include "common.h"
+
+/* Defined in board.h */
+enum als_id;
+
+/* Initialized in board.c */
+struct als_t {
+	const char const *name;
+	int (*read)(int *lux);
+};
+
+extern struct als_t als[];
+
+/**
+ * Read an ALS
+ *
+ * @param id		Which one?
+ * @param lux	        Put value here
+ *
+ * @return EC_SUCCESS, or non-zero if error.
+ */
+int als_read(enum als_id id, int *lux);
+
+#endif  /* __CROS_EC_ALS_H */