diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c index 938170b8998b8c835edec9113c217dae8c13f9a6..38319a69bd0a9de978fc688bded38fa3dea90def 100644 --- a/drivers/i2c/algos/i2c-algo-bit.c +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -604,9 +604,10 @@ static int __i2c_bit_add_bus(struct i2c_adapter *adap, int (*add_adapter)(struct i2c_adapter *)) { struct i2c_algo_bit_data *bit_adap = adap->algo_data; + int ret; if (bit_test) { - int ret = test_bus(bit_adap, adap->name); + ret = test_bus(bit_adap, adap->name); if (ret < 0) return -ENODEV; } @@ -615,7 +616,16 @@ static int __i2c_bit_add_bus(struct i2c_adapter *adap, adap->algo = &i2c_bit_algo; adap->retries = 3; - return add_adapter(adap); + ret = add_adapter(adap); + if (ret < 0) + return ret; + + /* Complain if SCL can't be read */ + if (bit_adap->getscl == NULL) { + dev_warn(&adap->dev, "Not I2C compliant: can't read SCL\n"); + dev_warn(&adap->dev, "Bus may be unreliable\n"); + } + return 0; } int i2c_bit_add_bus(struct i2c_adapter *adap)