Commit e1c86d22 authored Oct 15, 2008 by David Fries Committed by Linus Torvalds Oct 16, 2008

W1: ds2490.c ds_write_bit, grouping error, disable readback

ds_write_bit doesn't read the input buffer, so add COMM_ICP and a comment
that it will no longer generate a read back data byte. If there is an
extra data byte later on then it will cause an error and discard what data
was there. Corrected operator ordering for ds_send_control.

Signed-off-by: David Fries <david@fries.net>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1f4ec2d7

drivers/w1/masters/ds2490.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -525,7 +525,12 @@ static int ds_write_bit(struct ds_device *dev, u8 bit)
		int err;
		struct ds_status st;

		err = ds_send_control(dev, COMM_BIT_IO \| COMM_IM \| (bit) ? COMM_D : 0, 0);
		/* Set COMM_ICP to write without a readback. Note, this will
		* produce one time slot, a down followed by an up with COMM_D
		* only determing the timing.
		*/
		err = ds_send_control(dev, COMM_BIT_IO \| COMM_IM \| COMM_ICP \|
		(bit ? COMM_D : 0), 0);
		if (err)
		return err;