i2c: rcar_i2c: Fix order of restart and clear status

In case of repeated START condition, the restart has to be kicked
before clear status (MSR register). If it is kicked after clear status,
R-Car I2C may transfer data (TXD register) or receive data (RXD register)
instead of transferring slave address (MAR register).

Signed-off-by: Ryo Kataoka <ryo.kataoka.wt@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
This commit is contained in:
Nobuhiro Iwamatsu 2014-11-04 13:28:50 +09:00 committed by Heiko Schocher
parent 6dd38cc352
commit cd818a381d

View File

@ -119,10 +119,10 @@ rcar_i2c_raw_read(struct rcar_i2c *dev, u8 chip, uint addr)
/* set slave address, receive */
writel((chip << 1) | 1, &dev->icmar);
/* clear status */
writel(0, &dev->icmsr);
/* start master receive */
writel(MCR_MDBS | MCR_MIE | MCR_ESG, &dev->icmcr);
/* clear status */
writel(0, &dev->icmsr);
while ((readl(&dev->icmsr) & (MSR_MAT | MSR_MDR))
!= (MSR_MAT | MSR_MDR))