From 28c0a8433dd56146627d00907ad99084654741e8 Mon Sep 17 00:00:00 2001 From: Eddie Huang Date: Thu, 6 Aug 2015 15:22:11 +0800 Subject: [PATCH] i2c: mediatek: Fixup i2c ack error interrupt handling When occur i2c ack error, i2c controller generate two interrupts, first is the ack error interrupt, then the complete interrupt. i2c interrupt handler should keep the two interrupt value, and only call complete() for the complete interrupt. Signed-off-by: Liguo Zhang Signed-off-by: Eddie Huang Reviewed-by: Daniel Kurtz Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-mt65xx.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index e28ad4c17d3d..c02e6c018c39 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -557,15 +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; } -- 2.39.5