[PATCH v2 2/2] i2c: rcar: add R-Car Gen5 support

To support the next generation of R-Car SoCs, we need to skip polling
the reset status. SCMI doesn't support it and the firmware must take
care of this anyhow. Other than that, the driver works fine as-is.

Signed-off-by: Wolfram Sang <[email protected]>
---
Change since v1: * none

 drivers/i2c/busses/i2c-rcar.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index 5ce8f8e4856f..46508176712c 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -137,6 +137,7 @@ enum rcar_i2c_type {
 	I2C_RCAR_GEN2,
 	I2C_RCAR_GEN3,
 	I2C_RCAR_GEN4,
+	I2C_RCAR_GEN5,
 };
 
 struct rcar_i2c_priv {
@@ -900,8 +901,12 @@ static int rcar_i2c_do_reset(struct rcar_i2c_priv *priv)
 	if (ret)
 		return ret;
 
-	return read_poll_timeout_atomic(reset_control_status, ret, ret == 0, 1,
-					100, false, priv->rstc);
+	/* SCMI based resets don't need to poll for success */
+	if (priv->devtype < I2C_RCAR_GEN5)
+		return read_poll_timeout_atomic(reset_control_status, ret, ret == 0,
+						1, 100, false, priv->rstc);
+
+	return 0;
 }
 
 static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
@@ -1111,6 +1116,7 @@ static const struct of_device_id rcar_i2c_dt_ids[] = {
 	{ .compatible = "renesas,rcar-gen2-i2c", .data = (void *)I2C_RCAR_GEN2 },
 	{ .compatible = "renesas,rcar-gen3-i2c", .data = (void *)I2C_RCAR_GEN3 },
 	{ .compatible = "renesas,rcar-gen4-i2c", .data = (void *)I2C_RCAR_GEN4 },
+	{ .compatible = "renesas,rcar-gen5-i2c", .data = (void *)I2C_RCAR_GEN5 },
 	{},
 };
 MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
@@ -1194,9 +1200,15 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 			goto out_pm_put;
 		}
 
-		ret = reset_control_status(priv->rstc);
-		if (ret < 0)
-			goto out_pm_put;
+		/*
+		 * Gen5+ uses SCMI based reset which cannot report status.
+		 * Firmware has to ensure proper reset
+		 */
+		if (priv->devtype < I2C_RCAR_GEN5) {
+			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;
-- 
2.47.3