From 3a0964387beec2f12695fbdd0217e46c85eb3264 Mon Sep 17 00:00:00 2001
From: David Wu <david.wu@rock-chips.com>
Date: Thu, 18 Oct 2018 20:26:05 +0800
Subject: [PATCH] i2c: rk3x: Disable irq after i2c transfer finished
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In some case，log like this:

[   12.393926] rk3x-i2c ff150000.i2c: irq in STATE_IDLE, ipd = 0x51
[   12.416592] rk3x-i2c ff150000.i2c: irq in STATE_IDLE, ipd = 0x51

The i2c clock is disabled, so the pending irq clean is not
worked. Disable the interrupt after the i2c jobs were done,
the error log would not happen.

Change-Id: If04a2e2214d675410c67db0f131ee7ef635ddcb4
Signed-off-by: David Wu <david.wu@rock-chips.com>
---
 drivers/i2c/busses/i2c-rk3x.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index 653e471ca9cb..f9e5bb038713 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -79,6 +79,9 @@ enum {
 #define REG_INT_NAKRCV    BIT(6) /* NACK received */
 #define REG_INT_ALL       0xff
 
+/* Disable i2c all irqs */
+#define IEN_ALL_DISABLE   0
+
 /* Constants */
 #define WAIT_TIMEOUT      1000 /* ms */
 #define DEFAULT_SCL_RATE  (100 * 1000) /* Hz */
@@ -246,6 +249,11 @@ static inline void rk3x_i2c_clean_ipd(struct rk3x_i2c *i2c)
 	i2c_writel(i2c, REG_INT_ALL, REG_IPD);
 }
 
+static inline void rk3x_i2c_disable_irq(struct rk3x_i2c *i2c)
+{
+	i2c_writel(i2c, IEN_ALL_DISABLE, REG_IEN);
+}
+
 static inline void rk3x_i2c_disable(struct rk3x_i2c *i2c)
 {
 	u32 val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK;
@@ -1108,7 +1116,7 @@ static int rk3x_i2c_xfer(struct i2c_adapter *adap,
 				i2c_readl(i2c, REG_IPD), i2c->state);
 
 			/* Force a STOP condition without interrupt */
-			i2c_writel(i2c, 0, REG_IEN);
+			rk3x_i2c_disable_irq(i2c);
 			val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK;
 			val |= REG_CON_EN | REG_CON_STOP;
 			i2c_writel(i2c, val, REG_CON);
@@ -1125,6 +1133,10 @@ static int rk3x_i2c_xfer(struct i2c_adapter *adap,
 		}
 	}
 
+	/* Interrupt is disabled when i2c transfer is timeout */
+	if (timeout != 0)
+		rk3x_i2c_disable_irq(i2c);
+
 	rk3x_i2c_disable(i2c);
 
 	clk_disable(i2c->pclk);