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| author | Wolfram Sang <wsa+renesas@sang-engineering.com> | 2020-07-04 16:38:29 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-07-29 11:16:50 +0300 |
| commit | 6c3f2d342b90c24d8fc5dd9cb66f51fba058c566 (patch) | |
| tree | fbc35720080199e5482d8a13df73a91ddde61b89 /drivers/i2c | |
| parent | 535f366f079650db7f2de9e526fa9d82e3c618ac (diff) | |
| download | linux-6c3f2d342b90c24d8fc5dd9cb66f51fba058c566.tar.xz | |
i2c: rcar: always clear ICSAR to avoid side effects
[ Upstream commit eb01597158ffb1853a7a7fc2c57d4c844640f75e ]
On R-Car Gen2, we get a timeout when reading from the address set in
ICSAR, even though the slave interface is disabled. Clearing it fixes
this situation. Note that Gen3 is not affected.
To reproduce: bind and undbind an I2C slave on some bus, run
'i2cdetect' on that bus.
Fixes: de20d1857dd6 ("i2c: rcar: add slave support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-rcar.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 2c29f901d309..6e49e438ef5a 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -863,6 +863,7 @@ static int rcar_unreg_slave(struct i2c_client *slave) /* disable irqs and ensure none is running before clearing ptr */ rcar_i2c_write(priv, ICSIER, 0); rcar_i2c_write(priv, ICSCR, 0); + rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ synchronize_irq(priv->irq); priv->slave = NULL; @@ -966,6 +967,8 @@ static int rcar_i2c_probe(struct platform_device *pdev) if (ret < 0) goto out_pm_put; + rcar_i2c_write(priv, ICSAR, 0); /* Gen2: must be 0 if not using slave */ + if (priv->devtype == I2C_RCAR_GEN3) { priv->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL); if (!IS_ERR(priv->rstc)) { |