From: Marek Vasut <marek.vasut@gmail.com>
Date: Thu, 7 Mar 2019 02:41:08 +0000 (+0100)
Subject: i2c: rcar_iic: Read ICSR only once
X-Git-Tag: v2019.04-rc4~13^2~9
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=eb54682e91a0a3f9ca8629d67c5195ae54cfb1e9;p=oweals%2Fu-boot.git

i2c: rcar_iic: Read ICSR only once

Read ICSR only once to avoid missing interrupts. This happens on R8A7791
Porter during reset, when reading the PMIC register 0x13, which may fail
sometimes because of the missed DTE interrupt.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Heiko Schocher <hs@denx.de>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
---

diff --git a/drivers/i2c/rcar_iic.c b/drivers/i2c/rcar_iic.c
index e91fc86c1a..9d45f547d1 100644
--- a/drivers/i2c/rcar_iic.c
+++ b/drivers/i2c/rcar_iic.c
@@ -58,12 +58,14 @@ static void sh_irq_dte(struct udevice *dev)
 static int sh_irq_dte_with_tack(struct udevice *dev)
 {
 	struct rcar_iic_priv *priv = dev_get_priv(dev);
+	u8 icsr;
 	int i;
 
 	for (i = 0; i < IRQ_WAIT; i++) {
-		if (RCAR_IC_DTE & readb(priv->base + RCAR_IIC_ICSR))
+		icsr = readb(priv->base + RCAR_IIC_ICSR);
+		if (RCAR_IC_DTE & icsr)
 			break;
-		if (RCAR_IC_TACK & readb(priv->base + RCAR_IIC_ICSR))
+		if (RCAR_IC_TACK & icsr)
 			return -ETIMEDOUT;
 		udelay(10);
 	}