Make reading back the written value optional.

git-svn-id: http://lm-sensors.org/svn/i2c-tools/trunk@5393 7894878c-1315-0410-8ee3-d5d059ff63e0

CHANGES

@@ -23,6 +23,7 @@ SVN
           Add support for short writes (SMBus send byte)
           Better error message on missing adapter functionality
           Set the data value mask with -m
+          Make reading back the written value optional
   i2c-stub-from-dump: Add support for partial dumps
                       Report if only garbage is found in dump file
                       Behave properly when i2c-stub is already loaded

tools/i2cset.8

@@ -7,6 +7,7 @@ i2cset \- set I2C registers
 .RB [ -f ]
 .RB [ -y ]
 .RB [ "-m mask" ]
+.RB [ -r ]
 .I i2cbus
 .I chip-address
 .I data-address
@@ -46,6 +47,11 @@ are taken from \fIvalue\fR, while bits set to 0 will be read from
 this parameter assumes that the read and write operations for the specified
 mode are symmetrical for the device you are accessing. This may or may not
 be the case, as neither I2C nor SMBus guarantees this.
+.TP
+.B -r
+Read back the value right after writing it, and compare the result with the
+value written. This used to be the default behavior. The same limitations
+apply as those of option \fB-m\fR.
 .PP
 There are three required options to i2cset. \fIi2cbus\fR indicates the number
 or name of the I2C bus to be scanned.  This number should correspond to one of

tools/i2cset.c

@@ -134,7 +134,7 @@ int main(int argc, char *argv[])
 	char filename[20];
 	int pec = 0;
 	int flags = 0;
-	int force = 0, yes = 0, version = 0;
+	int force = 0, yes = 0, version = 0, readback = 0;
 
 	/* handle (optional) flags first */
 	while (1+flags < argc && argv[1+flags][0] == '-') {
@@ -147,6 +147,7 @@ int main(int argc, char *argv[])
 				maskp = argv[2+flags];
 			flags++;
 			break;
+		case 'r': readback = 1; break;
 		default:
 			fprintf(stderr, "Error: Unsupported option "
 				"\"%s\"!\n", argv[1+flags]);
@@ -308,6 +309,11 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	if (!readback) { /* We're done */
+		close(file);
+		exit(0);
+	}
+
 	switch (size) {
 	case I2C_SMBUS_BYTE:
 		/* No readback */