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authorFederico Vaga <federico.vaga@cern.ch>2019-02-14 09:51:31 +0100
committerWolfram Sang <wsa@the-dreams.de>2019-02-14 17:55:30 +0100
commit2dc9834688ae3ba057d46e60525a11ec146ae3df (patch)
tree71578e34cb22aa59ce1da25fb91d01fd9b9814af /drivers/i2c
parenti2c: ocores: stop transfer on timeout (diff)
downloadlinux-2dc9834688ae3ba057d46e60525a11ec146ae3df.tar.xz
linux-2dc9834688ae3ba057d46e60525a11ec146ae3df.zip
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 <federico.vaga@cern.ch> Acked-by: Peter Korsgaard <peter@korsgaard.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-ocores.c9
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index aa852028d8c1..fcc25582c648 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 @@ out:
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;
}