5.15-stable review patch. If anyone has any objections, please let me know.
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From: Wolfram Sang wsa+renesas@sang-engineering.com
[ Upstream commit ea5ea84c9d3570dc06e8fc5ee2273eaa584aa3ac ]
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: 3b770017b03a ("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 Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/busses/i2c-rcar.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 1efc0230c2cba..e24ced623c9ad 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -803,6 +803,10 @@ 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; @@ -1098,6 +1102,7 @@ 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)) @@ -1106,6 +1111,9 @@ 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);