From eb54682e91a0a3f9ca8629d67c5195ae54cfb1e9 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Thu, 7 Mar 2019 03:41:08 +0100 Subject: [PATCH] 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 Cc: Heiko Schocher Cc: Nobuhiro Iwamatsu Reviewed-by: Heiko Schocher --- drivers/i2c/rcar_iic.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/rcar_iic.c b/drivers/i2c/rcar_iic.c index e91fc86..9d45f54 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); } -- 2.7.4