From 62fd7817223c06d692b03f9f0ce49ec3c67fb048 Mon Sep 17 00:00:00 2001
From: Jean Delvare <khali@linux-fr.org>
Date: Tue, 2 Nov 2010 12:57:11 +0000
Subject: [PATCH] Reorganize the temporary sparse subfeature table. It's a
 little larger now, but this make it possible to add more feature types
 without increasing the code complexity beyond reason. Define constants and
 use them to make the code even easier to understand.

If anyone is really worried about the relatively large memory
allocation, one way to improve the situation would be a two-pass
approach. But remember the memory is only needed for a short time...


git-svn-id: http://lm-sensors.org/svn/lm-sensors/trunk@5874 7894878c-1315-0410-8ee3-d5d059ff63e0
---
 lib/sysfs.c | 44 +++++++++++++++++++++++---------------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/lib/sysfs.c b/lib/sysfs.c
index f8f0bf77..79cf559f 100644
--- a/lib/sysfs.c
+++ b/lib/sysfs.c
@@ -136,15 +136,19 @@ static int sysfs_foreach_busdev(const char *bus_type,
 
 char sensors_sysfs_mount[NAME_MAX];
 
+#define MAX_MAIN_SENSOR_TYPES	6
+#define MAX_OTHER_SENSOR_TYPES	1
 #define MAX_SENSORS_PER_TYPE	24
 #define MAX_SUBFEATURES		8
-#define MAX_SENSOR_TYPES	6
-/* Room for all 6 types (in, fan, temp, power, energy, current) with all
-   their subfeatures + VID + misc features */
-#define ALL_POSSIBLE_SUBFEATURES \
-				(MAX_SENSORS_PER_TYPE * MAX_SUBFEATURES * \
-				 MAX_SENSOR_TYPES * 2 + \
-				 MAX_SENSORS_PER_TYPE + 1)
+#define FEATURE_SIZE		(MAX_SUBFEATURES * 2)
+#define FEATURE_TYPE_SIZE	(MAX_SENSORS_PER_TYPE * FEATURE_SIZE)
+
+/* Room for all 6 main types (in, fan, temp, power, energy, current) and 1
+   other type (VID) with all their subfeatures + misc features */
+#define SUB_OFFSET_OTHER	(MAX_MAIN_SENSOR_TYPES * FEATURE_TYPE_SIZE)
+#define SUB_OFFSET_MISC		(SUB_OFFSET_OTHER + \
+				 MAX_OTHER_SENSOR_TYPES * FEATURE_TYPE_SIZE)
+#define ALL_POSSIBLE_SUBFEATURES	(SUB_OFFSET_MISC + 1)
 
 static
 int get_type_scaling(sensors_subfeature_type type)
@@ -404,16 +408,18 @@ static int sensors_read_dynamic_chip(sensors_chip_features *chip,
 		   sorted table */
 		switch (sftype) {
 		case SENSORS_SUBFEATURE_VID:
-			i = nr + MAX_SENSORS_PER_TYPE * MAX_SUBFEATURES *
-			    MAX_SENSOR_TYPES * 2;
+			i = SUB_OFFSET_OTHER +
+			    ((sftype >> 8) - SENSORS_FEATURE_VID) *
+			    FEATURE_TYPE_SIZE +
+			    nr * FEATURE_SIZE + (sftype & 0xFF);
 			break;
 		case SENSORS_SUBFEATURE_BEEP_ENABLE:
-			i = MAX_SENSORS_PER_TYPE * MAX_SUBFEATURES *
-			    MAX_SENSOR_TYPES * 2 + MAX_SENSORS_PER_TYPE;
+			i = SUB_OFFSET_MISC +
+			    ((sftype >> 8) - SENSORS_FEATURE_BEEP_ENABLE);
 			break;
 		default:
-			i = (sftype >> 8) * MAX_SENSORS_PER_TYPE *
-			    MAX_SUBFEATURES * 2 + nr * MAX_SUBFEATURES * 2 +
+			i = (sftype >> 8) * FEATURE_TYPE_SIZE +
+			    nr * FEATURE_SIZE +
 			    ((sftype & 0x80) >> 7) * MAX_SUBFEATURES +
 			    (sftype & 0x7F);
 		}
@@ -450,11 +456,9 @@ static int sensors_read_dynamic_chip(sensors_chip_features *chip,
 		if (!all_subfeatures[i].name)
 			continue;
 
-		if (i >= MAX_SENSORS_PER_TYPE * MAX_SUBFEATURES *
-		    MAX_SENSOR_TYPES * 2 ||
-		    i / (MAX_SUBFEATURES * 2) != prev_slot) {
+		if (i >= SUB_OFFSET_MISC || i / FEATURE_SIZE != prev_slot) {
 			fnum++;
-			prev_slot = i / (MAX_SUBFEATURES * 2);
+			prev_slot = i / FEATURE_SIZE;
 		}
 	}
 
@@ -472,12 +476,10 @@ static int sensors_read_dynamic_chip(sensors_chip_features *chip,
 			continue;
 
 		/* New main feature? */
-		if (i >= MAX_SENSORS_PER_TYPE * MAX_SUBFEATURES *
-		    MAX_SENSOR_TYPES * 2 ||
-		    i / (MAX_SUBFEATURES * 2) != prev_slot) {
+		if (i >= SUB_OFFSET_MISC || i / FEATURE_SIZE != prev_slot) {
 			ftype = all_subfeatures[i].type >> 8;
 			fnum++;
-			prev_slot = i / (MAX_SUBFEATURES * 2);
+			prev_slot = i / FEATURE_SIZE;
 
 			dyn_features[fnum].name = get_feature_name(ftype,
 						all_subfeatures[i].name);