[PATCH] i2c/mpc: Fix ISR return value

[Danielle Costantino]

I have been using the driver with this modification for the past 6 months
and it has been stable in an industrial environment.I had made a few other
changes that also improve reliability (using ppc in_8 and out_8 and eieio
barriers to ensure in-order execution. This lets you remove the unneeded
double read of the status register. I also added a more robust recovery
function to handle force of bus master-ship, and clearing the arb lost
interrupt that is generated. currently this can cause the isr to trigger
and cause superfluous interrupts. I have not posted this patch because of
the extensive changes,

I will ack this patch.

On Fri, Jan 30, 2015 at 2:24 AM, Amit Tomar <Amit.Tomar at freescale.com>
wrote:

> ISR should not return IRQ_HANDLED for not handling anything.
> This patch fixes the return value of ISR for the same case.
>
>
> Signed-off-by: Amit Singh Tomar <amit.tomar at freescale.com>
> ---
> drivers/i2c/busses/i2c-mpc.c |    3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
> index 0edf630..7a3136f 100644
> --- a/drivers/i2c/busses/i2c-mpc.c
> +++ b/drivers/i2c/busses/i2c-mpc.c
> @@ -95,8 +95,9 @@ static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
>         i2c->interrupt = readb(i2c->base + MPC_I2C_SR);
>         writeb(0, i2c->base + MPC_I2C_SR);
>         wake_up(&i2c->queue);
> +       return IRQ_HANDLED;
>     }
> -  return IRQ_HANDLED;
> +  return IRQ_NONE;
> }
>
> /* Sometimes 9th clock pulse isn't generated, and slave doesn't release
> --
> 1.7.9.5
>
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-- 
- Danielle Costantino
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