5.4-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 91811a31b68d3765b3065f4bb6d7d6d84a7cfc9f ]
Baruch reported an OOPS when using the designware controller as target only. Target-only modes break the assumption of one transfer function always being available. Fix this by always checking the pointer in __i2c_transfer.
Reported-by: Baruch Siach baruch@tkos.co.il Closes: https://lore.kernel.org/r/4269631780e5ba789cf1ae391eec1b959def7d99.171276197... Fixes: 4b1acc43331d ("i2c: core changes for slave support") [wsa: dropped the simplification in core-smbus to avoid theoretical regressions] Signed-off-by: Wolfram Sang wsa+renesas@sang-engineering.com Tested-by: Baruch Siach baruch@tkos.co.il Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/i2c-core-base.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 964e8a29b27b4..cf9ad03bb34de 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1965,13 +1965,18 @@ static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, * Returns negative errno, else the number of messages executed. * * Adapter lock must be held when calling this function. No debug logging - * takes place. adap->algo->master_xfer existence isn't checked. + * takes place. */ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { unsigned long orig_jiffies; int ret, try;
+ if (!adap->algo->master_xfer) { + dev_dbg(&adap->dev, "I2C level transfers not supported\n"); + return -EOPNOTSUPP; + } + if (WARN_ON(!msgs || num < 1)) return -EINVAL;
@@ -2038,11 +2043,6 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { int ret;
- if (!adap->algo->master_xfer) { - dev_dbg(&adap->dev, "I2C level transfers not supported\n"); - return -EOPNOTSUPP; - } - /* REVISIT the fault reporting model here is weak: * * - When we get an error after receiving N bytes from a slave,