mfd: max8925: Fix possible NULL pointer dereference on i2c_new_dummy error

During probe the driver allocates dummy I2C devices for RTC and ADC
with i2c_new_dummy() but it does not check the return value of this
calls.

In case of error (i2c_new_device(): memory allocation failure or I2C
address cannot be used) this function returns NULL which is later used
by i2c_unregister_device().

If i2c_new_dummy() fails for RTC or ADC devices, fail also the probe
for main MFD driver.

Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
This commit is contained in:
Krzysztof Kozlowski 2014-02-11 11:03:33 +01:00 committed by Lee Jones
parent ed26f87b9f
commit 96cf3dedc4

View File

@ -181,9 +181,18 @@ static int max8925_probe(struct i2c_client *client,
mutex_init(&chip->io_lock);
chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
if (!chip->rtc) {
dev_err(chip->dev, "Failed to allocate I2C device for RTC\n");
return -ENODEV;
}
i2c_set_clientdata(chip->rtc, chip);
chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
if (!chip->adc) {
dev_err(chip->dev, "Failed to allocate I2C device for ADC\n");
i2c_unregister_device(chip->rtc);
return -ENODEV;
}
i2c_set_clientdata(chip->adc, chip);
device_init_wakeup(&client->dev, 1);