From 553515e5c54dbf3340cd6773aaf0acb53291d6ad Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 13 Oct 2007 23:56:31 +0200 Subject: i2c/pcf8574: No arbitrary initialization Do not initialize the PCF8574 with an arbitrary value. Users will have to write the initial value to sysfs themselves. Signed-off-by: Jean Delvare Acked-by: Aurelien Jarno --- Documentation/i2c/chips/pcf8574 | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'Documentation/i2c/chips/pcf8574') diff --git a/Documentation/i2c/chips/pcf8574 b/Documentation/i2c/chips/pcf8574 index 2752c8ce3167..5c1ad1376b62 100644 --- a/Documentation/i2c/chips/pcf8574 +++ b/Documentation/i2c/chips/pcf8574 @@ -62,8 +62,6 @@ if the corresponding output is set as 1, otherwise the current output value, that is to say 0. The write file is read/write. Writing a value outputs it on the I/O -port. Reading returns the last written value. - -On module initialization the chip is configured as eight inputs (all -outputs to 1), so you can connect any circuit to the PCF8574(A) without -being afraid of short-circuit. +port. Reading returns the last written value. As it is not possible +to read this value from the chip, you need to write at least once to +this file before you can read back from it. -- cgit v1.2.3