Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

[cascardo/linux.git] / drivers / i2c / busses / i2c-mt65xx.c

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 9920eef..c02e6c0 100644 (file)
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -59,6 +59,7 @@
 #define I2C_DMA_START_EN               0x0001
 #define I2C_DMA_INT_FLAG_NONE          0x0000
 #define I2C_DMA_CLR_FLAG               0x0000
+#define I2C_DMA_HARD_RST               0x0002
 
 #define I2C_DEFAULT_SPEED              100000  /* hz */
 #define MAX_FS_MODE_SPEED              400000
@@ -81,6 +82,7 @@ enum DMA_REGS_OFFSET {
        OFFSET_INT_FLAG = 0x0,
        OFFSET_INT_EN = 0x04,
        OFFSET_EN = 0x08,
+       OFFSET_RST = 0x0c,
        OFFSET_CON = 0x18,
        OFFSET_TX_MEM_ADDR = 0x1c,
        OFFSET_RX_MEM_ADDR = 0x20,
@@ -262,6 +264,10 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
                      I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
        writew(control_reg, i2c->base + OFFSET_CONTROL);
        writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN);
+
+       writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
+       udelay(50);
+       writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
 }
 
 /*
@@ -551,15 +557,22 @@ static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
 {
        struct mtk_i2c *i2c = dev_id;
        u16 restart_flag = 0;
+       u16 intr_stat;
 
        if (i2c->dev_comp->auto_restart)
                restart_flag = I2C_RS_TRANSFER;
 
-       i2c->irq_stat = readw(i2c->base + OFFSET_INTR_STAT);
-       writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR
-               | I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_STAT);
+       intr_stat = readw(i2c->base + OFFSET_INTR_STAT);
+       writew(intr_stat, i2c->base + OFFSET_INTR_STAT);
 
-       complete(&i2c->msg_complete);
+       /*
+        * when occurs ack error, i2c controller generate two interrupts
+        * first is the ack error interrupt, then the complete interrupt
+        * i2c->irq_stat need keep the two interrupt value.
+        */
+       i2c->irq_stat |= intr_stat;
+       if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag))
+               complete(&i2c->msg_complete);
 
        return IRQ_HANDLED;
 }