Commit 8859942e authored Aug 13, 2006 by Domen Puncer Committed by Greg Kroah-Hartman Sep 26, 2006

i2c-au1550: Fix timeout problem

i2c-au1550: Fix timeout problem

Fix from Jordan Crouse:
If the transmit and recieve FIFOS are not empty, forceably flush them
rather then waiting for them to drain on their own.

This solves at least a problem reported by Clem Taylor:
http://www.linux-mips.org/archives/linux-mips/2006-05/msg00240.html


(1% of I2C transactions would timeout)

Signed-off-by: Domen Puncer <domen.puncer@ultra.si>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 643bd3fb

drivers/i2c/busses/i2c-au1550.c

+10 −4

Original line number	Diff line number	Diff line
		@@ -118,13 +118,19 @@ do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd)

		/* Reset the FIFOs, clear events.
		*/
		sp->psc_smbpcr = PSC_SMBPCR_DC;
		stat = sp->psc_smbstat;
		sp->psc_smbevnt = PSC_SMBEVNT_ALLCLR;
		au_sync();

		if (!(stat & PSC_SMBSTAT_TE) \|\| !(stat & PSC_SMBSTAT_RE)) {
		sp->psc_smbpcr = PSC_SMBPCR_DC;
		au_sync();
		do {
		stat = sp->psc_smbpcr;
		au_sync();
		} while ((stat & PSC_SMBPCR_DC) != 0);
		udelay(50);
		}

		/* Write out the i2c chip address and specify operation
		*/