@@ -257,6 +257,14 @@ static void rcar_i2c_init(struct rcar_i2c_priv *priv)
}
}
+static void rcar_i2c_reset_slave(struct rcar_i2c_priv *priv)
+{
+ rcar_i2c_write(priv, ICSIER, 0);
+ rcar_i2c_write(priv, ICSSR, 0);
+ rcar_i2c_write(priv, ICSCR, SDBS);
+ rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */
+}
+
static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
{
int ret;
@@ -1033,11 +1041,8 @@ static int rcar_unreg_slave(struct i2c_client *slave)
/* ensure no irq is running before clearing ptr */
disable_irq(priv->irq);
- rcar_i2c_write(priv, ICSIER, 0);
- rcar_i2c_write(priv, ICSSR, 0);
+ rcar_i2c_reset_slave(priv);
enable_irq(priv->irq);
- rcar_i2c_write(priv, ICSCR, SDBS);
- rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */
priv->slave = NULL;
@@ -1152,7 +1157,9 @@ static int rcar_i2c_probe(struct platform_device *pdev)
goto out_pm_disable;
}
- rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */
+ /* Bring hardware to known state */
+ rcar_i2c_init(priv);
+ rcar_i2c_reset_slave(priv);
if (priv->devtype < I2C_RCAR_GEN3) {
irqflags |= IRQF_NO_THREAD;
When probing, the hardware is not brought into a known state. This may be a problem when a hypervisor restarts Linux without resetting the hardware, leaving an old state running. Make sure the hardware gets initialized, especially interrupts should be cleared and disabled. Reported-by: Dirk Behme <dirk.behme@de.bosch.com> Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Closes: https://lore.kernel.org/r/20240702045535.2000393-1-dirk.behme@de.bosch.com Fixes: 6ccbe607132b ("i2c: add Renesas R-Car I2C driver") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- Should go to for-current. Changes since v1: * renamed new function to *_reset_slave() instead of *_init_slave() which is more appropriate * do not mention refactorization in commit message * added Fixes tag drivers/i2c/busses/i2c-rcar.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)