Hi Tommy,
On Fri, 2024-10-18 at 11:49 +0800, Tommy Huang wrote:
> In the original code, the device reset would not be triggered
> when the driver is set to multi-master and bus is free.
That's not how I read the existing code. As it stands, if it's multi-
master and busy we do the recovery, however, if it's multi-master and
free, or busy but not multi-master, or free and not multi-master, then
we do the reset.
> It needs to be considered with multi-master condition.
Is there a specific circumstance you've found that's problematic? Can
you provide some more details about that scenario?
>
> Fixes: <f327c686d3ba> ("i2c: aspeed: Reset the i2c controller when timeout occurs")
>
> Signed-off-by: Tommy Huang <tommy_huang@xxxxxxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-aspeed.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
> index cc5a26637fd5..7639ae3ace67 100644
> --- a/drivers/i2c/busses/i2c-aspeed.c
> +++ b/drivers/i2c/busses/i2c-aspeed.c
> @@ -716,14 +716,15 @@ static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
> if (time_left == 0) {
> /*
> * In a multi-master setup, if a timeout occurs, attempt
> - * recovery. But if the bus is idle, we still need to reset the
> - * i2c controller to clear the remaining interrupts.
> + * recovery device. But if the bus is idle,
> + * we still need to reset the i2c controller to clear
> + * the remaining interrupts or reset device abnormal condition.
> */
> - if (bus->multi_master &&
> - (readl(bus->base + ASPEED_I2C_CMD_REG) &
> - ASPEED_I2CD_BUS_BUSY_STS))
> - aspeed_i2c_recover_bus(bus);
> - else
> + if ((readl(bus->base + ASPEED_I2C_CMD_REG) &
> + ASPEED_I2CD_BUS_BUSY_STS)){
> + if (bus->multi_master)
> + aspeed_i2c_recover_bus(bus);
The change doesn't seem match the commit message. In this case you've
punched a hole - if the bus is busy but _not_ multi-master, we neither
do the reset _nor_ the recovery.
Which is what you intended? The implementation? Or the prose
description?
Now, back to the implementation, punching this hole seems reasonable on
the surface, but I guess we need to keep in mind that time_left has
also expired...
> + } else
> aspeed_i2c_reset(bus);
>
> /*
Andrew
