If the Interrupt Flag (IF) is not set, we should not handle the IRQ:
- the line can be shared with other devices
- it can be a spurious interrupt
To avoid reading twice the status register, the ocores_process() function
expects it to be read by the caller.
Signed-off-by: Federico Vaga <federico.vaga@xxxxxxx>
---
drivers/i2c/busses/i2c-ocores.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 98c0ef74882b..274d6eb22a2c 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -139,10 +139,9 @@ static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg)
return i2c->getreg(i2c, reg);
}
-static void ocores_process(struct ocores_i2c *i2c)
+static void ocores_process(struct ocores_i2c *i2c, u8 stat)
{
struct i2c_msg *msg = i2c->msg;
- u8 stat = oc_getreg(i2c, OCI2C_STATUS);
if ((i2c->state == STATE_DONE) || (i2c->state == STATE_ERROR)) {
/* stop has been sent */
@@ -209,9 +208,13 @@ static void ocores_process(struct ocores_i2c *i2c)
static irqreturn_t ocores_isr(int irq, void *dev_id)
{
struct ocores_i2c *i2c = dev_id;
+ u8 stat = oc_getreg(i2c, OCI2C_STATUS);
unsigned long flags;
int ret;
+ if (!(stat & OCI2C_STAT_IF))
+ return IRQ_NONE;
+
/*
* We need to protect i2c against a timeout event (see ocores_xfer())
* If we cannot take this lock, it means that we are already in
@@ -222,7 +225,7 @@ static irqreturn_t ocores_isr(int irq, void *dev_id)
if (!ret)
return IRQ_HANDLED;
- ocores_process(i2c);
+ ocores_process(i2c, stat);
spin_unlock_irqrestore(&i2c->xfer_lock, flags);
--
2.15.0
