i2c: rcar: ensure Gen3+ reset does not disturb local targets

R-Car Gen3+ needs a reset before every controller transfer. That erases
configuration of a potentially in parallel running local target
instance. To avoid this disruption, avoid controller transfers if a
local target is running. Also, disable SMBusHostNotify because it
requires being a controller and local target at the same time.

Fixes: 3b770017b0 ("i2c: rcar: handle RXDMA HW behaviour on Gen3")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
This commit is contained in:
Wolfram Sang 2024-07-11 10:30:44 +02:00 committed by Andi Shyti
parent fea6b5ebb7
commit ea5ea84c9d

View File

@ -883,6 +883,10 @@ static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv)
{
int ret;
/* Don't reset if a slave instance is currently running */
if (priv->slave)
return -EISCONN;
ret = reset_control_reset(priv->rstc);
if (ret)
return ret;
@ -1175,6 +1179,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
if (of_property_read_bool(dev->of_node, "smbus"))
priv->flags |= ID_P_HOST_NOTIFY;
/* R-Car Gen3+ needs a reset before every transfer */
if (priv->devtype >= I2C_RCAR_GEN3) {
priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
if (IS_ERR(priv->rstc)) {
@ -1185,6 +1190,9 @@ static int rcar_i2c_probe(struct platform_device *pdev)
ret = reset_control_status(priv->rstc);
if (ret < 0)
goto out_pm_put;
/* hard reset disturbs HostNotify local target, so disable it */
priv->flags &= ~ID_P_HOST_NOTIFY;
}
ret = platform_get_irq(pdev, 0);