From 2dc9834688ae3ba057d46e60525a11ec146ae3df Mon Sep 17 00:00:00 2001 From: Federico Vaga Date: Thu, 14 Feb 2019 09:51:31 +0100 Subject: [PATCH] i2c: ocores: do not handle IRQ if IF is not set 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 Acked-by: Peter Korsgaard Reviewed-by: Andrew Lunn Signed-off-by: Wolfram Sang --- 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 aa852028d8c15..fcc25582c6488 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/drivers/i2c/busses/i2c-ocores.c @@ -143,10 +143,9 @@ 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); unsigned long flags; /* @@ -223,8 +222,12 @@ 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); + + if (!(stat & OCI2C_STAT_IF)) + return IRQ_NONE; - ocores_process(i2c); + ocores_process(i2c, stat); return IRQ_HANDLED; }