Hi Sifan,
On 27/07/15 12:47, Sifan Naeem wrote:
> Clear line status and all interrupts when transaction is complete,
> as not doing so might leave unserviced interrupts that might be
Do you have a specific example of when this might happen, and whether it
could occur after img_i2c_complete_transaction()?
I'm just wondering if it would be better to do this before starting
every new message instead of after handling the last irq that is of
interest (maybe somewhere in img_i2c_xfer).
> handled in the context of a new transfer. Soft reset if the the
> transfer failed to bring back the i2c block to a reset state.
>
> Fixes: 27bce4 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver")
> Signed-off-by: Sifan Naeem <sifan.naeem@xxxxxxxxxx>
> Cc: Stable kernel (v3.19+) <stable@xxxxxxxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-img-scb.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c
> index 341130e..bbfee33 100644
> --- a/drivers/i2c/busses/i2c-img-scb.c
> +++ b/drivers/i2c/busses/i2c-img-scb.c
> @@ -626,7 +626,10 @@ static void img_i2c_complete_transaction(struct img_i2c *i2c, int status)
> img_i2c_switch_mode(i2c, MODE_INACTIVE);
> if (status) {
> i2c->msg_status = status;
> - img_i2c_transaction_halt(i2c, false);
> + img_i2c_soft_reset(i2c);
This seems like overkill. This will only happen in a couple of cases:
(1) an automatic mode ack error, which is completely recoverable.
(2) a fatal error (clock low timeout), which switches mode to MODE_FATAL
anyway, preventing further transactions.
Cheers
James
> + } else {
> + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0);
> + img_i2c_writel(i2c, SCB_CLEAR_REG, ~0);
> }
> complete(&i2c->msg_complete);
> }
>
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